Nutrition and health

Objectives:
Soy products contain several compounds with anti-inflammatory properties like genistein and daidzein which reported to act through different pathways. However, there are inconsistent results and lack of any comprehensive review regarding randomized controlled trials which assess the effect of soy products on inflammatory markers. Therefore, this review article has been conducted.

Does soy product supplementation reduce levels of inflammatory markers, like CRP, IL-6?

Study design:
This review article included 51 RCTs.

Results and conclusions:
The investigators found soy product supplementation significantly reduced CRP levels [MD = -0.27 mg/L, 95% CI = -0.51 to -0.02, p = 0.028] but it did not affect IL-6 [MD = 0.0 pg/mL, 95% CI = -0.06 to 0.06, p = 0.970] and TNF-α [MD = -0.04 pg/mL, 95% CI = -0.11 to 0.03, p = 0.252].

The investigators found subgroup analysis showed that soy supplementation had a significant impact on decreasing IL-6 and TNF-α levels when studies had a long-term intervention (≥12 weeks) and used low dose isoflavone (100 mg/day).

The investigators concluded there is a significant reduction in CRP levels after soy product supplementation.

Original title:
The effects of soy supplementation on inflammatory biomarkers: A systematic review and meta-analysis of randomized controlled trials by Asbaghi O, Yaghubi E, […], Ghaedi E.

Link:
https://pubmed.ncbi.nlm.nih.gov/32979840/

Additional information of El Mondo:
Find here more information/studies about soy consumption and chronic disease.

Objectives:
There is some inconclusive evidence for the role of fish consumption in susceptibility to multiple sclerosis (MS). Therefore, this review article has been conducted.

Does fish consumption reduce multiple sclerosis (MS)?

Study design:
This review article included 6 observational studies.

Results and conclusions:
The investigators found that the consumption of fish (at least 0.5 servings of fish per week) significantly decreased the risk of multiple sclerosis with 23% [OR = 0.77, 95% CI = 0.64 to 0.92, p-value = 0.004, I2 = 54.7%] compared with controls.

The investigators concluded that dietary intake of at least 0.5 servings of fish per week during adolescence and after reduce the risk of multiple sclerosis; however, further studies are required to prove this preventive effect.

Original title:
Dietary fish intake and the risk of multiple sclerosis: a systematic review and meta-analysis of observational studies by Rezaeizadeh H, Mohammadpour Z, […], Homayon IA.

Link:
https://pubmed.ncbi.nlm.nih.gov/32787642/

Additional information of El Mondo:
Find here more information/studies about fish consumption.

Objectives:
Probiotics are being used increasingly in pregnant women, whereas the efficiency on pregnancy outcomes is yet lacking. Therefore, this review article has been conducted.

Have probiotic supplements during pregnancy positive effects on pregnancy outcomes, such as eczema, gestational age?

Study design:
This review article included 18 RCTs with a total of 4,356 pregnant women.

Results and conclusions:
The investigators found probiotic supplementation during pregnancy significantly decreased risk of atopic eczema with 32% [RR = 0.68, 95% CI = 0.58 to 0.81, p 0.001, without significant heterogeneity].

The investigators found probiotic supplementation during pregnancy significantly decreased risk of eczema with 21% [RR = 0.79, 95% CI = 0.68 to 0.91, p = 0.002, without significant heterogeneity].

The investigators found probiotic supplementation during pregnancy was associated with a prolonged gestational age [WMD = 0.09, 95 % CI = 0.04 to 0.15, p = 0.001 with insignificant heterogeneity].
However, probiotic supplementation during pregnancy had no significant effect on birth weight [p = 0.851].

The investigators found probiotic supplementation during pregnancy significantly decreased risk of death with 66% [RR = 0.34, 95% CI = 0.13 to 0.91, p = 0.031, without evidence of heterogeneity].

The investigators found probiotic supplementation during pregnancy significantly decreased risk of necrotising enterocolitis (NEC) with 62% [RR = 0.38, 95% CI = 0.18 to 0.11, p = 0.012, without evidence of heterogeneity].

The investigators concluded probiotic supplementation in pregnant women is beneficial for atopic eczema, eczema, gestational age, death and necrotising enterocolitis.

Original title:
Effect of probiotic supplementation in pregnant women: a meta-analysis of randomised controlled trials by Kuang L and Jiang Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31856928

Additional information of El Mondo:
Find more information/studies on probiotic and pregnancy right here.

Necrotizing enterocolitis (NEC) is a devastating disease that affects mostly the intestine of premature infants. The wall of the intestine is invaded by bacteria, which cause local infection and inflammation that can ultimately destroy the wall of the bowel (intestine). Such bowel wall destruction can lead to perforation of the intestine and spillage of stool into the infant’s abdomen, which can result in an overwhelming infection and death.
 

Objectives:
The relationship between dietary pattern and the risk of chronic obstructive pulmonary disease (COPD) has been described; however, the exclusive role of dietary factors remains controversial. Therefore, this review article has been conducted.

Does a dietary intake of fruits and vegetables, dietary fiber, fish, n-3 or n-6 fatty acids and antioxidant vitamins reduce risk of COPD in adults?

Study design:
This review article included 10 cohort, 6 case-control and 20 cross-sectional studies.

To assess usual dietary intake, 28 studies had used food frequency questionnaires (FFQ), of which 2 studies had used FFQ and a 24-hour recall, 3 studies had used the crosscheck dietary method, 1 study had assessed with only 24-hour recall and 1 study had used weighted household food records.

Results and conclusions:
The investigators found a significantly reduced risk of 26% [relative risk = 0.74, 95% CI = 0.65 to 0.85] for COPD for the highest fruit intake group compared with the lowest intake group.
This significantly reduced risk was 29% in cohort studies [RR = 0.71, 95% CI = 0.63 to 0.79, I2 = 0.0%].

The investigators found a significantly reduced risk of 47% [relative risk = 0.53, 95% CI = 0.39 to 0.74, I2 = 0.0%, p = 0.65] for COPD mortality for the highest fruit intake group compared with the lowest intake group.

The investigators found a significantly reduced risk of 35% [relative risk = 0.65, 95% CI = 0.55 to 0.78] for COPD for the highest dietary fiber intake group compared with the lowest intake group.
This significantly reduced risk was 39% in cohort studies [RR = 0.61, 95% CI = 0.54 to 0.68, I2 = 0.0%, p = 0.9].

The investigators found a significantly reduced risk of 29% [relative risk = 0.71, 95% CI = 0.58 to 0.85] for COPD for the highest fish intake group compared with the lowest intake group.

The investigators found a significantly reduced risk of 11% [relative risk = 0.89, 95% CI = 0.76 to 0.99] for COPD for the highest vitamin C dietary intake group compared with the lowest intake group.

The investigators found no association between the risk of COPD and the intake of vegetables, n-3 fatty acids, vitamin E and β-carotene.

The investigators concluded that a higher dietary intake of fruit, dietary fiber, fish and vitamine C reduce the risk of COPD in adults.

Original title:
Dietary Factors and Risk of Chronic Obstructive Pulmonary Disease: A Systemic Review and Meta-Analysis by Seyedrezazadeh E, Moghaddam MP, […], Kolahdooz F.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7309892/

Additional information of El Mondo:
Find here more information/studies about fruit, dietary fiber, fish and vitamine C.

Objectives:
Vitamin D deficiency has been related to the risk of sepsis. However, previous studies showed inconsistent results regarding the association between serum 25-hydroxyvitamin D (25 (OH)D) and mortality risk in septic patients. Therefore, this review article has been conducted.

Does a low serum 25-hydroxyvitamin D (vitamin D level in blood) increase mortality risk in septic patients?

Study design:
This review article included 8 follow-up studies (4 were prospective and the other 4 were retrospective) with 1,736 septic patients.

The sample sizes of the included studies varied from 57 to 610.
The mean ages of the patients included in each study ranged from 57 to 75 years and the proportions of male patients varied from 43% to 71%.

Optimal vitamin D level, vitamin D insufficiency, vitamin D deficiency and severe vitamin D deficiency are defined as serum 25 (OH)D > 30 ng/mL, 21-29 ng/mL and  20 ng/mL, 10 ng/mL, respectively.

There was no publication bias.

Results and conclusions:
The investigators found meta-analysis with a random-effect model showed that septic patients with lower serum 25 (OH)D ( 30 ng/ml) at admission was associated with a significantly increased mortality risk of 93% [adjusted RR = 1.93, 95% CI = 1.41 to 2.63, p  0.001, I2 = 63%, p = 0.003].
Sensitivity analysis by excluding one study at a time did not significantly change the results.

The investigators found subgroup analyses according to the severity of vitamin D deficiency showed that patients with severe vitamin D deficiency ( 10 ng/mL) was significantly associated with a 92% higher mortality risk [adjusted RR = 1.92, 95% CI = 1.09 to 2.55, p  0.001].
But the associations were not significant for vitamin D insufficiency (25 (OH)D = 20-30 ng/mL) or deficiency (25 (OH)D = 10-20 ng/mL).

The investigators found further analyses showed that the association between lower serum 25(OH) D and higher mortality risk were consistent in studies applied different diagnostic criteria for sepsis (SIRS, Sepsis-2.0 or Sepsis-3.0), short-term (within 1 month) and long-term studies (3-12 months) and in prospective and retrospective studies.

The investigators concluded that severe vitamin D deficiency ( 10 ng/mL) is independently associated with increased mortality in patients with sepsis. Large-scale prospective studies are needed to validate these findings.

Original title:
Serum 25-Hydroxyvitamin D and the risk of mortality in adult patients with Sepsis: a meta-analysis by Li Y and Ding S.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7057612/

Additional information of El Mondo:
Find here more information/studies about vitamin D.

Objectives:
Do higher gestational vitamin D levels (vitamin D levels of the mother during pregnancy) decrease risk of multiple sclerosis (MS) in offspring?

Study design:
This review article included 4 case-control studies of moderate to low risk of bias.

Factors identified as determinants of heterogeneity were the definitions of vitamin D deficiency, the characteristics of study participants and the quality of the study.

Results and conclusions:
The investigators found that higher levels of gestational vitamin D significantly reduced risk of multiple sclerosis in offspring with 37% [OR = 0.63, 95% CI = 0.47 to 0.84] in random effects models and in a stratified analysis based on study quality.

The investigators concluded higher levels of gestational vitamin D reduce risk of multiple sclerosis in offspring.

Original title:
Gestational vitamin D and offspring risk of multiple sclerosis: a systematic review and meta-analysis by Jasper EA, Nidey NL, […], Ryckman KK.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32014337

Additional information of El Mondo:
Find more information/studies on vitamin D and pregnancy right here.

 

Objectives:
Micronutrients’ deficiency is a common phenomenon among a majority of the population residing in the low- and middle-income countries (LMICs) especially among women and children. Given the widespread prevalence of micronutrients’ deficiency in LMICs, iron-fortified foods could be of potential benefits for both the mother and the development of fetus. Therefore, this review article has been conducted.

Does iron fortification increase hemoglobin (Hb) concentration during pregnancy and have iron fortification positive effects on specific maternal and pregnancy outcomes?

Study design:
This review article included 12 RCTs (n = 3,872).

The weighted mean difference (WMD) and relative risk (RR) were calculated using random-effects models. Sources of heterogeneity were explored through meta-regression.

The funnel plot was symmetrical, indicating that there was absence of any publication bias which was confirmed using Egger's weighted regression method [Egger test, ρ = 0.69].

Results and conclusions:
The investigators found the mean change in hemoglobin concentration was significantly higher in the group of mothers with iron fortification when compared with the control group [WMD = 4.45 g/L, 95% CI = 2.73 to 6.17 g/L, I2 = 83%, ρ 0.00001].

The investigators found in meta-regression analysis that the duration of feeding was positively associated with the effect size.

The investigators concluded iron fortification increases hemoglobin (Hb) concentration during pregnancy. Further research is required to explore the benefits of iron fortification on maternal and neonatal health outcomes during pregnancy.

Original title:
Meta-analysis Approach on Iron Fortification and Its Effect on Pregnancy and Its Outcome Through Randomized, Controlled Trials by Athe R, Dwivedi R, […], Banset U.  

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7114015/

Additional information of El Mondo:
Find more information/studies food fortification and iron right here.

Objectives:
Multiple sclerosis (MS) is a demyelinating and disabling inflammatory disease of the central nervous system. Multiple sclerosis is triggered by complex environmental factors which mostly affect genetically the susceptible young people. Emerging data has suggested that changes of homocysteine (Hcy), vitamin B12 and folate serum levels may be associated with multiple sclerosis. However, previous findings are not always consistent. Therefore, this review aricle has been conducted.

Does a low serum homocysteine, vitamin B12 or folate level increase risk of multiple sclerosis?

Study design:
This review article included 21 original studies with 1,738 multiple sclerosis patients and 1,424 controls (patients without multiple sclerosis). There were 17 studies for measuring homocysteine, 16 studies for measuring vitamin B12 and 13 studies for measuring folate in patients with multiple sclerosis, respectively.

Results and conclusions:
The investigators found patients with multiple sclerosis (MS) had higher serum levels of homocysteine [SMD = 0.64, 95% CI = 0.33 to 0.95, p 0.0001] compared with control groups.

The investigators found no significant differences of SMD for vitamin B12 [SMD = -0.08, 95% CI = -0.35 to 0.20, p = 0.58] or folate [SMD = 0.07, 95% CI = -0.14 to 0.28, p = 0.52] between MS and controls.

The investigators found subgroup analysis demonstrated that there was statistically significant difference for homocysteine between relapsing-remitting MS (RRMS) patients and controls with a SMD of 0.67 [95% CI = 0.21 to 1.13, p = 0.004].

However, no significant difference of homocysteine serum levels between secondary progressive MS patients or primary progressive MS patients and controls.

The investigators found no significant difference of homocysteine levels in females [SMD = 0.22, 95% CI = -0.16 to 0.60, p = 0.25] or males [SMD = 0.56, 95% CI = -0.13 to 1.26, p = 0.11] between MS patients and controls.

The investigators concluded higher serum levels of homocysteine increase risk of multiple sclerosis (MS), especially for relapsing-remitting MS (RRMS) patients. Functional studies are required to assess the effects of homocysteine on patients with MS at the molecular level.

Original title:
Serum levels of Homocysteine, Vitamin B12 and Folate in Patients with Multiple Sclerosis: an Updated Meta-Analysis by Li X, Yuan J, [...], Hu W.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7085269/

Additional information of El Mondo:
Find here more information/studies about lowering serum levels of homocysteine.

Objectives:
Physical exercise may offer multiple benefits to patients with chronic kidney disease (CKD). However, it was not traditionally recommended because of the possibility of impairing renal function and increasing proteinuria. Therefore, this review aricle has been conducted.

Does low-intensity physical exercise offer benefits to patients with chronic kidney disease?

Study design:
This review article included 21 RCTs with a intervention of at least 12 weeks and 927 patients.

The frequency of low-intensity physical exercise in 14 studies was 3 times per week during 30 minutes.

Results and conclusions:
The investigators found no differences in glomerular filtration rate or proteinuria between the intervention group (group with low-intensity physical exercise) and the control group (group without low-intensity physical exercise) [SMD = -0.3, p = 0.81 and SMD = 26.6, p = 0.82].

The investigators found positive effects on peak oxygen consumption [SMD = 2.5, p 0.001], functional capacity [SMD = 56.6, p 0.001], upper limb strength [SMD = 6.8, p 0.001] and haemoglobin [SMD = 0.3, p = 0.003] for the intervention group.

The investigators found an improvement on the quality of life, using the KDQOL-36 survey [SMD = 3.56, p = 0.02] and the SF-36 survey [SMD = 6.66, p = 0.02] for the intervention group.

The investigators concluded low-intensity physical exercise routinely has no negative impact on renal function. On the contrary, it improves aerobic and functional capacity, impacting positively on the quality of life.

Original title:
Impact of physical exercise in patients with chronic kidney disease: Sistematic review and meta-analysis by Villanego F, Naranjo J, […], Mazuecos A.

Link:
https://reader.elsevier.com/reader/sd/pii/S0211699520300266?token=62CEB2BCF50CE23B396565B5DC989F795AEEB75C666C74AA410FD2172DB39F90DBBB5D72BF3B4347C0C8AD2FEF8B0110

Additional information of El Mondo:
Find here more information/studies about kidney disease and sport nutrition.

Low-intensity physical exercises are a casual walk, a stretch session, a beginners' yoga class or tai chi.

Objectives:
Is there a causal relationship between dietary anthocyanins and reduced levels of systemic and vascular inflammation?

Study design:
This review article included 32 RCTs.

Results and conclusions:
The investigators found that dietary anthocyanins significantly decreased levels of C-reactive protein (CRP) [-0.33 mg/L, 95% CI = -0.55 to -0.11, p = 0.00], interleukin-6 (IL-6) [-0.41 ρg/mL, 95% CI = -0.70 to -0.13, p = 0.004], tumor necrosis factor-alpha (TNF-α) [-0.64 ρg/mL, 95% CI = -1.18 to -0.09, p = 0.023], intercellular adhesion molecule-1 [-52.4 ng/mL, 95% CI = -85.7 to -19.1, p = 0.002] and vascular adhesion molecule-1 (VCAM-1)  [-49.6 ng/mL, 95% CI = -72.7 to -26.5, p  0.001]. 

The investigators found that dietary anthocyanins significantly increased adiponectin level [0.75 μg/mL, 95% CI = 0.23 to 1.26, p = 0.004].

The investigators found subgroup analyses showed that administration of higher doses of anthocyanins (>300 mg/day) significantly decreased levels of CRP, IL-6, TNF-α and VCAM-1.

The investigators concluded that >300 mg/day dietary anthocyanins reduce the levels of systemic and vascular inflammation in the subjects.

Original title:
Impact of dietary anthocyanins on systemic and vascular inflammation: Systematic review and meta-analysis on randomised clinical trials by Fallah AA, Sarmast E, […], Jafari T.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31669599

Additional information of El Mondo:
Find here more information/studies about inflammation and anthocyanins.

Inflammation in the body can be measured by the following biomarker; the pro-inflammatory cytokines. The pro-inflammatory cytokines are the C-reactive protein (CRP), IL-1, interleukin-6 (IL-6), IL-8, MCP-1, the vascular adhesion molecule-1 (VCAM-1) and tumor necrosis factor alpha (TNF-α).

Objectives:
Omega-3 fatty acid and vitamin E or D co-supplementation may be an important approach to improve metabolic status in gestational diabetes, but the results are conflicting. Therefore, this review article has been conducted.

Do omega-3 fatty acid and vitamin E or D co-supplementation improve metabolic status in gestational diabetes?

Study design:
This review article included 4 RCTs.

Results and conclusions:
The investigators found omega-3 fatty acid and vitamin E or D co-supplementation was associated with a significantly reduced fasting plasma glucose level [MD = -10.47, 95% CI = -15.33 to -5.61, p  0.0001], homeostasis model of assessment-insulin resistance level [MD = -1.6, 95% CI= -2.44 to -0.77, p = 0.0002], malondialdehyde level [MD = -1.00, 95% CI = -1.05 to -0.95, p  0.00001] and triglycerides level [MD = 26.22, 95% CI = -38.94 to -13.51, p  0.0001].

The investigators found omega-3 fatty acid and vitamin E or D co-supplementation was associated with a significantly increased antioxidant capacity level [MD = 173.51, 95% CI = 164.72-182.30, p  0.00001].

The investigators found omega-3 fatty acid and vitamin E or D co-supplementation showed no effect on nitric oxide level [MD = 5.95, 95% CI = -7.48 to 19.37, p = 0.39] or total cholesterol level [MD = 1.63, 95% CI = -13.46 to 16.72, p = 0.83].

The investigators concluded omega-3 fatty acid and vitamin E or D co-supplementation have a favourable effect on metabolic status in gestational diabetes.

Original title:
Influence of omega-3 fatty acid and vitamin co-supplementation on metabolic status in gestational diabetes: A meta-analysis of randomized controlled studies by Li F, Pei L, […], Ye H.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32145487

Additional information of El Mondo:
Find more information/studies on diabetes, pregnancy, omega-3 fatty acid, vitamin D and E right here.

Objectives:
Is there a causal relationship between intake of pomegranate and decreased risk of getting inflammation in adults?

Study design:
This review article included 16 randomized controlled trials (RCTs) involving 572 subjects.

Results and conclusions:
The investigators found when compared to placebo, that pomegranate supplementation significantly reduced hs-CRP levels [WMD = -6.57 mg/L, 95% CI = -10.04 to -3.10, p = 0.000].

The investigators found when compared to placebo, that pomegranate supplementation significantly reduced IL-6 levels [WMD = -1.68 pg/mL, 95% CI = -3.52 to -0.157, p = 0.000].

The investigators found when compared to placebo, that pomegranate supplementation significantly reduced TNF-α levels [WMD = -2.37 pg/mL, 95% CI = -3.67 to -1.07, p = 0.00].

The investigators found no association between pomegranate supplementation and CRP levels [WMD = 2.19 mg/dL, 95% CI = -3.28 to 7.67, p = 0.61], E-selectin levels [WMD = 8.42 ng/mL, 95% CI = -22.9 to 39.8, p = 0.599], ICAM levels [WMD = -17.38 ng/mL, 95% CI = -53.43 to 18.66, p = 0.107], VCAM levels [WMD = -69.32 ng/mL, 95% CI = -229.26 to 90.61, p = 0.396] or MDA levels [WMD = 0.031 μmol/L, 95% CI = -1.56 to 0.218, p = 0.746].

The investigators concluded pomegranate supplementation reduces hs-CRP levels, IL-6 levels and TNF-α levels in adults.

Original title:
The effects of pomegranate supplementation on biomarkers of inflammation and endothelial dysfunction: A meta-analysis and systematic review by Wang P, Zhang Q, [...], Yao G.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32147056

Additional information of El Mondo:
Find here more information/studies about fruit and chronic diseases.

Inflammation in humans can be measured by biomarkers, such as highly sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6) and the tumor necrosis factor alpha (TNF-α).

Inflammation in humans can lower the resistance. A low resistance makes the body susceptible to diseases.
 

Objectives:
The efficacy of n-3 fatty acids supplementation on the prevention of pregnancy-induced hypertension or preeclampsia remains unclear. Therefore, this meta-analysis (systematic review) has been conducted.

Does n-3 fatty acids supplementation (EPA and/or DHA and/or ALA) decrease risk of pregnancy-induced hypertension and preeclampsia during pregnancy?

Study design:
This review article included 14 RCTs.

Results and conclusions:
The investigators found that n-3 fatty acids supplementation significantly reduced risk of preeclampsia with 18% [RR = 0.82, 95% CI = 0.70 to 0.97, p = 0.024. I2 = 19.0%].
However, n-3 fatty acids supplementation did not associated with a reduced risk of pregnancy-induced hypertension [RR = 0.98, 95% CI = 0.90 to 1.07, p = 0.652, I2 = 0%].

The investigators concluded n-3 fatty acids supplementation (EPA and/or DHA and/or ALA)  reduces risk of preeclampsia during pregnancy.

Original title:
Efficacy of n-3 fatty acids supplementation on the prevention of pregnancy induced-hypertension or preeclampsia: A systematic review and meta-analysis by Bakouei F, Delavar MA, […], Taheri Z.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32039806

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Find more information/studies on n-3 fatty acids, hypertension and pregnancy right here.

 

Objectives:
The activity of hepatitis B virus (HBV) as a risk factor for the incidence and progression of chronic kidney disease (CKD) has not been clarified. Therefore, this review article has been conducted.

Does hepatitis B virus infection increase risk of chronic kidney disease?

Study design:
This review article included 33 studies with a total of 7,849,849 patients.

Results and conclusions:
The investigators found in 11 cohort studies with 1,056,645 patients, that a positive HBV serologic status (hepatitis B virus infection) significantly increased risk of incidence of chronic kidney disease with 40% [adjusted HR = 1.40, 95% CI = 1.16 to 1.69, p 0.001, I2 = 49.5%, p 0.0001].

The investigators found in 10 cross-sectional studies with 3,222,545 patients, no relationship between hepatitis B virus infection and prevalence of chronic kidney disease [adjusted OR = 1.04, 95% CI = 0.90 to 1.218, p = 0.5].

The investigators found meta-regression analysis reported a relationship between positive HBsAg status and incidence of chronic kidney disease in the general population [p 0.015].

The investigators concluded hepatitis B virus infection increases risk of developing of chronic kidney disease in the adult general population. Studies aimed to understand the mechanisms responsible of such association are underway.

Original title:
HBV infection is a risk factor for chronic kidney disease: Systematic review and meta-analysis by Fabrizi F, Cerutti R, […], Messa P.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32037008

Additional information of El Mondo:
Find here more information/studies about kidney disease.
 

Objectives:
Lead is a known risk factor for amyotrophic lateral sclerosis (ALS). However, the results of studies exploring the relationship between lead exposure and the occurrence of ALS are inconsistent. Therefore, this review article has been conducted.

Does a high lead exposure increase risk of ALS?

Study design:
This review article included 11 case-control studies.

Results and conclusions:
The investigators found a high lead exposure significantly increased risk of ALS with 28% [OR = 1.28, 95% CI = 1.02 to 1.63].
Subgroup and sensitivity analyses showed stable results.

The investigators concluded a high lead exposure increases risk of ALS.

Original title:
Population-based study of environmental/occupational lead exposure and amyotrophic lateral sclerosis: a systematic review and meta-analysis by Meng E, Mao Y, […], Jin W.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31578652

Additional information of El Mondo:
Find here more information/studies about chronic diseases.
 

Objectives:
Many studies have been reported that dietary meat intake may be associated with the risk of asthma in children, but the results are inconsistent. Therefore, this review article has been conducted.

Does dietary meat intake increase asthma in children?

Study design:
This review article included a total of 9 articles.

No publication bias was detected.

Results and conclusions:
The investigators found dietary meat intake 3 or more times per week compared with never/occasionally intake had no significant association with asthma risk among children [OR = 1.27, 95% CI  =  0.80-2.01, p =  0.308].
Not significant because OR of 1 was found in the 95% CI of 0.80 to 2.01. OR of 1 means no risk/association.

The investigators found, similarly, daily dietary intake of meat did not affect the risk of asthma in children when compared with never/occasionally intake [OR  =  1.13, 95% CI  =  0.93-1.37, p  =  0.234].

The investigators concluded dietary meat intake is not a risk factor for asthma in children. Due to some limitations that exist in this review article, more studies are needed to further assess the association between dietary meat intake and asthma risk in children.

Original title:
Dietary meat intake and risk of asthma in children: evidence from a meta-analysis by Zhang D, Cao L, [...], Wang Z.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31895767

Additional information of El Mondo:
Find here more information/studies about meat consumption and chronic diseases.
 

Objectives:
Does dehydroepiandrosterone (DHEA) supplementation improve the outcomes of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) in women with diminished ovarian reserve (DOR) and/or poor ovarian response (POR)?

Study design:
This review article included 9 RCTs, published between 2010 and 2017.
The sample sizes ranged from 24 to 208, with a total of 862 patients.
All of included patients had been diagnosed with diminished ovarian reserve (DOR) and/or poor ovarian response (POR).

The treatment intervention was 75 mg daily DHEA versus placebo.

The lack of significant asymmetry of funnel plot indicated the lack of potential publication bias in the included studies.

Results and conclusions:
The investigators found in a pooled analysis using the random effects model revealed a statistically significant increase in retrieved oocytes in the DHEA group, compared to the control group [MD = 0.91, 95% CI = 0.23 -1.59, p = 0.009, I2  = 53%, p = 0.06].

The investigators found in 8 studies (405 in the DHEA group and 415 in the control group) a statistically significant increase in the clinical pregnancy rate in the DHEA group compared to the control group [RR = 1.27, 95% CI = 1.01 -1.61, p = 0.04, I2 = 0%, p = 0.57].

The investigators found in 5 studies (189 in the DHEA group and 190 in the control group) a statistically significant increase in the live birth rate in the DHEA group, compared to the control group [RR = 1.76, 95% CI = 1.17 -2.63, p = 0.006, I2  = 0%, p = 0.43].

The investigators found in 3 studies (96 in the DHEA group and 99 in the control group) no significant difference in the miscarriage rates between the DHEA and control groups [RR = 0.37, 95% CI = 0.12-1.13, p = 0.08, I2 = 25%, p = 0.26].

The investigators concluded 75 mg daily DHEA supplementation increases the retrieved oocytes, clinical pregnancy rate and live birth rate in women with diminished ovarian reserve and/or poor ovarian response, who are undergoing in vitro fertilization or intracytoplasmic sperm injection.

Original title:
The Effect of Dehydroepiandrosterone (DHEA) Supplementation on IVF or ICSI: A Meta-Analysis of Randomized Controlled Trials by Xu L, Hu C, […], Li Y.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6620181/

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Your body naturally produces the hormone dehydroepiandrosterone (DHEA) in the adrenal gland. In turn, DHEA helps produce other hormones, like testosterone and estrogen. Natural dehydroepiandrosterone levels peak in early adulthood and then slowly fall as you age.

 

Objectives:
The morbidity of eczema has increased in the recent years and the methods to prevent or ameliorate its effects are becoming more important. Therefore, this review article has been conducted.

Do vitamin supplements reduce risk of eczema?

Study design:
This review article included 10 RCTs with a total of 456 patients.
The sample sizes ranged from 5 to 57. The studies were published from 2008 to 2018.
5 studies were conducted on atopic dermatitis, 3 studies were conducted on pediatric atopic dermatitis and 2 studies were conducted on winter-related atopic dermatitis.

Results and conclusions:
The investigators found that the SCORAD index or EASI scores significantly decreased in patients given vitamin D3 (cholecalciferol) supplements [mean difference = -5.96, 95% CI = -7.69 to -4.23, I2 = 33%].

The investigators found that the SCORAD index significantly decreased after the topical application of vitamin B12-containing cream [mean difference = -3.19, 95% CI = -4.27 to -2.10, I2 = 0%]. 

The investigators found that the SCORAD index significantly improved after vitamin E supplementation [mean difference = -5.72, 95% CI = -11.41 to -0.03, I2 = 0%]. 

The investigators concluded vitamin D3, B12 and E supplements could be important therapeutics to help manage eczema patients.

Original title:
Assessment of the Effectiveness of Vitamin Supplement in Treating Eczema: A Systematic Review and Meta-Analysis by Zhu Z, Yang Z, [...], Liu H.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6875217/

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Find here more information/studies about vitamin B12, D and E and chronic disease.

Objectives:
Free fatty acids, also known as nonesterified fatty acids, are proinflammatory molecules that induce insulin resistance in nonpregnant individuals. Nevertheless, the concentration of these molecules has not been systematically addressed in pregnant women. Therefore, this review article has been conducted.

Do higher plasma levels of free fatty acids increase risk of gestational diabetes mellitus?

Study design:
This review article included 12 case-control studies with a total of 2,426 women, from these, 21% (507/2,426) had a diagnosis of having gestational diabetes.

The mean gestational age at inclusion was 30.3 weeks of gestation.
The mean maternal age was 29 years.
No significant publication bias was found nor a trend towards greater results in small studies.

Results and conclusions:
The investigators found in random-effects model, when compared to controls, women with gestational diabetes had higher levels of free fatty acids [SMD = 0.86, 95% CI = 0.54-1.18, p 0.001, I2 = 91%].
Pooled results showed higher plasma levels of free fatty acid among women with gestational diabetes mellitus during the second trimester of pregnancy [SMD = 1.05 vs. 0.75].

The investigators found meta-regression analysis showed that the gestational age at inclusion was the only cofactor influencing the mean levels of free fatty acids, indicating a trend towards lower plasma levels of free fatty acids later in gestation [estimate = -0.074, 95% CI = -0.143 to -0.004, p = 0.036].

The investigators concluded that plasma levels of free fatty acids are higher in women diagnosed with gestational diabetes mellitus and that this difference is higher during the second trimester of pregnancy. However, more investigation is needed to assess the potential role of free fatty acids in the prediction of gestational diabetes earlier in pregnancy.

Original title:
Plasma Levels of Free Fatty Acids in Women with Gestational Diabetes and Its Intrinsic and Extrinsic Determinants: Systematic Review and Meta-Analysis by Villafan-Bernal JR, Acevedo-Alba M, […], Martinez-Portilla RJ.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6721400/

Additional information of El Mondo:
Find more information/studies on fatty acids and pregnancy right here.
 

Objectives:
Low-potassium diets are recommended to reduce serum potassium (Sk) and prevent complications of chronic kidney disease (CKD), but evidence underpinning this recommendation has not been systematically reviewed and synthesized. Therefore, this review article has been conducted.

Do patients with chronic kidney disease benefit from low-potassium diets?

Study design:
This review article included 7 studies  with 3,489 participants.

Results and conclusions:
The investigators found in very-low-quality studies that restricted (1,295 mg/d) versus unrestricted (1,570 mg/d) dietary potassium lowered serum potassium by 0.22 mEq/L [95% CI = -0.33 to -0.10, I2 = 0%].

The investigators found in very-low-quality studies that lower (1,725 mg/d) versus higher (4,558 mg/d) dietary potassium was not significantly associated with disease progression [HR = 1.14, 95% CI = 0.77 to 1.70, I2 = 57%].

The investigators found in very-low-quality studies that lower (1,670 mg/d), compared with higher (4,414 mg/d) dietary potassium intake was associated with a 40% reduction in mortality hazard [HR = 0.60, 95% CI = 0.40 to 0.89, I2 = 56%].

The investigators concluded very-low-quality evidence supports consensus that dietary potassium restriction reduces serum potassium in normokalemia and is associated with a reduced risk of death in those with chronic kidney disease. However, high-quality randomized controlled trials are needed to confirm these findings.

Original title:
Effect of Dietary Potassium Restriction on Serum Potassium, Disease Progression, and Mortality in Chronic Kidney Disease: A Systematic Review and Meta-Analysis by Morris A, Krishnan N, […], Lycett D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31734057

Additional information of El Mondo:
Find here more information/studies about potassium and kidney disease.

Objectives:
Parkinson's disease (PD) is the most common neurodegenerative disease after Alzheimer's dementia. Whereas the exact etiology of Parkinson's disease remains unknown, risk of developing Parkinson's disease seems to be related to a combination of genetic and environmental factors. This also includes abnormal exposure to trace elements of nutritional and toxicological interest. Therefore, this review article has been conducted.

Is there a relationship between exposure to trace elements and Parkinson’s disease risk?

Study design:
This review article included 56 case-control studies reporting data for selenium (cases/controls: 588/721), copper (2,190/2,522), iron (2,956/3,469) and zinc (1,798/1,913) contents in cerebrospinal fluid (CSF) and blood.

Results and conclusions:
The investigators found patients with Parkinson's disease had significantly higher levels of selenium in cerebrospinal fluid compared with controls [+51.6%, WMD = 5.49, 95% CI = 2.82 to 8.15], while levels in serum were similar [-0.2%, WMD = -0.22, 95% CI = -8.05 to 7.62].

The investigators found patients with Parkinson's disease had non-significantly higher levels of copper in cerebrospinal fluid compared with controls [+4.5%, WMD = 1.87, 95% CI = -3.59 to 7.33] and non-significantly lower levels of copper in serum [WMD = -42.79, 95% CI = -134.35 to 48.76].

The investigators found patients with Parkinson's disease had significantly higher levels of iron in cerebrospinal fluid compared with controls [+9.5%, WMD = 9.92, 1.23 to 18.61] and significantly lower levels of iron both in serum/plasma [-5.7%, WMD = -58.19, 95% CI = -106.49 to -9.89] and whole blood [-10.8%, WMD = -95.69, 95% CI = -157.73 to -33.65].

The investigators found patients with Parkinson's disease had significantly lower levels of zinc in cerebrospinal fluid compared with controls [-10.8%, WMD = -7.34, 95% CI = -14.82 to -0.14] and significantly lower levels of zinc in serum/plasma [-7.5%, WMD = -79.93, 95% CI = -143.80 to -16.06].

The investigators found a longer duration of the disease tends to be associated with overall lower trace element levels in either cerebrospinal fluid or blood.

The investigators concluded higher levels of both selenium and iron in cerebrospinal fluid increase Parkinson's disease, while higher levels of zinc in cerebrospinal fluid decrease Parkinson's disease.

Original title:
Selenium and Other Trace Elements in the Etiology of Parkinson's Disease: A Systematic Review and Meta-Analysis of Case-Control Studies by Adani G, Filippini T, […], Vinceti M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31454800

Additional information of El Mondo:
Find here more information/studies about iron, zinc, selenium and chronic disease
 

Objectives:
Does omega-3 fatty acids supplementation improve serum levels of inflammatory biomarkers (C-reactive protein [CRP], high-sensitivity CRP [hs-CRP], tumor necrosis factor-alpha, interleukin-6) and albumin in patients on hemodialysis?

Study design:
This review article included 8 RCTs comprising 371 patients on hemodialysis.

Results and conclusions:
The investigators found omega-3 supplementation significantly decreased serum levels of CRP in patients on hemodialysis [SMD = -1.95 mg/dL, 95% CI = -3.09 to -0.80] and hs-CRP [SMD = -2.09, 95% CI = -3.62 to -0.56].

The investigators found, however, omega-3 supplementation did not significantly improved albumin [SMD = 0.91, 95% CI = -0.78 to 2.59], tumor necrosis factor-alpha [SMD = -1.51, 95% CI = -3.24 to 0.22] and interleukin-6 levels [SMD = 0.72, 95% CI = -0.56 to 1.99] in patients on hemodialysis.

The investigators concluded omega-3 supplementation leads to a significant decrease in serum levels of CRP and hs-CRP in patients on hemodialysis.

Original title:
The Effect of Omega-3 Supplementation on Serum Levels of Inflammatory Biomarkers and Albumin in Hemodialysis Patients: A Systematic Review and Meta-analysis by Dezfouli M, Moeinzadeh F, [...], Feizi A.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31420233

Additional information of El Mondo:
Find here more information/studies about omega-3 fatty acids and kidney disease.  
 

Objectives:
Maternal folic acid supplementation is considered mandatory in almost every country in the world to prevent congenital malformations. However, little is known about the association of maternal folic acid intake with the occurrence of childhood cancer. Therefore, this review article has been conducted.

Does maternal folic acid supplementation during pregnancy reduce risk of childhood cancer?

Study design:
This review article included 17 case-control studies.

Results and conclusions:
The investigators found in random-effects model, maternal folic acid supplementation during pregnancy significantly reduced risk of childhood acute lymphoblastic leukaemia with 25% [OR = 0.75, 95% CI = 0.66 to 0.86].
Significantly because OR of 1 was not found in the 95% CI of 0.66 to 0.86. OR of 1 means no risk/association.

The investigators found in random-effects model, there was no significant association between maternal folic acid supplementation during pregnancy and acute myeloid leukaemia [OR = 0.70, 95% CI = 0.46 to 1.06] or childhood brain tumours [OR = 1.02, 95% CI = 0.88 to 1.19].
No significant because OR of 1 was found in the 95% CI of 0.88 to 1.19. OR of 1 means no risk/association.

The investigators concluded maternal folic acid supplementation during pregnancy reduces risk of childhood acute lymphoblastic leukaemia. Thus, healthcare professionals are recommended to provide regular health education and health promotion to the community on the benefits of folic acid supplementation during pregnancy.

Original title:
The Protective Effect of Maternal Folic Acid Supplementation on Childhood Cancer: A Systematic Review and Meta-analysis of Case-control Studies by Wan Ismail WR, Abdul Rahman R, […],Nawi AM.

Link:
https://www.jpmph.org/journal/view.php?doi=10.3961/jpmph.19.020

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Find more information/studies on folic acid and pregnancy right here.
 

Objectives:
Environmental risk factors regrading rheumatoid arthritis (RA) have not been explored extensively. Selenium (Se), zinc (Zn) and copper (Cu) nutrients were reported to associate with rheumatoid arthritis, but the results were inconsistent. Therefore, this review article has been conducted.

Is there a relationship between serum selenium, zinc and copper levels and rheumatoid arthritis risk?

Study design:
This review article included 41 studies.

Results and conclusions:
The investigators found meta-analysis of 16 studies involving 806 rheumatoid arthritis patients and 959 health controls showed that serum selenium levels [SMD = -1.04, 95% CI = -1.58 to -0.50] were significantly decreased in rheumatoid arthritis patients.

The investigators found meta-analysis of 23 studies involving 1,398 rheumatoid arthritis patients and 1,299 health controls showed that serum zinc levels [SMD = -1.20, 95% CI = -1.74 to -0.67] were significantly decreased in rheumatoid arthritis patients.

The investigators found meta-analysis of 26 studies involving 1,723 rheumatoid arthritis patients and 1,451 health controls showed that serum copper levels [SMD = 1.26, 95% CI = 0.63 to 1.89] were significantly increased in rheumatoid arthritis patients.

The investigators found meta-regression reported that steroid use was positively related to serum level of selenium in rheumatoid arthritis [β = 0.041, 95% CI = 0.002 to 0.079].

The investigators found differences in serum selenium, zinc and copper between rheumatoid arthritis patients and controls were all related with the geographical distribution.

The investigators concluded patients with rheumatoid arthritis have significant decreased serum selenium and zinc levels and increased serum copper levels than health controls, suggesting potential roles of selenium, zinc and copper in the pathogenesis of rheumatoid arthritis. Patients and rheumatologist should give enough attention to the monitor of these elements during follow up.

Original title:
Common trace metals in rheumatoid arthritis: A systematic review and meta-analysis by Ma Y, Zhang X, […], Pan F.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31442958

Additional information of El Mondo:
Find here more information/studies about selenium, zinc and copper and chronic disease.


 

Objectives:
Systematic inflammation plays a major role in all stages of chronic diseases. Recent evidence suggests that coenzyme Q10 (CoQ10), as an anti-inflammatory agent, has shown beneficial effects on the inflammatory process of various human diseases. However, several trials have examined the effects of coenzyme Q10 on pro-inflammatory cytokines with contrasting results. Therefore, this review article has been conducted.

Does coenzyme Q10 supplementation reduce inflammation in humans?

Study design:
This review article included 9 RCTs with a total of 509 patients (269 in the coenzyme Q10 arm and 240 in the control arm).

Results and conclusions:
The investigators found that oral coenzyme Q10 supplementation (60-500 mg/day for 8-12 weeks) resulted in significant reduction of TNF-α [SMD = -0.44, 95% CI = -0.81 to -0.07 mg/dL, I2 = 66.1%, p  = 0.00] and IL-6 levels [SMD = -0.37, 95% CI = -0.65 to -0.09, I2 = 57.2%, p  = 0.01], respectively.

The investigators found subgroup analyses represented a significant reduction of TNF-α and IL-6 levels in patients with BMI  26.
Due to the small number of studies and patients included in each subgroup, these subgroup analyses need to be interpreted cautiously.

The investigators concluded there is a significant effect of 60-500 mg/day coenzyme Q10 supplements for 8-12 weeks on some of the inflammatory markers among patients with chronic diseases which could attenuate the inflammatory state. However, well-designed studies with a larger sample size are required. Note that the results should be interpreted with caution because of the evidence of heterogeneity and limited number of studies.

Original title:
Can coenzyme Q10 supplementation effectively reduce human tumor necrosis factor-α and interleukin-6 levels in chronic inflammatory diseases? A systematic review and meta-analysis of randomized controlled trials by Vafa M.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31185284

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Find here more information/studies about chronic disease and coenzyme Q10.