Nutrition and health

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:
Previous studies did not draw a consistent conclusion about the effects of vitamin K combined with vitamin D on human skeletal quality. Therefore, this review article has been conducted.

Does vitamin K combined with vitamin D supplementation increase bone mineral density (BMD)?

Study design:
This review article included 8 RCTs with a total of 971 participants.

Results and conclusions:
The investigators found vitamin K combined with vitamin D supplementation significantly increased total bone mineral density (BMD) [pooled effect size = 0.316, 95% CI = 0.031 to 0.601].

The investigators found vitamin K combined with vitamin D supplementation significantly decreased levels of undercarboxylated osteocalcin [effect size = -0.945, 95% CI = -1.113 to -0.778].

The investigators found simultaneously, subgroup analysis showed that K2 or vitamin K (not specified) supplement less than 500 μg/d, when combined with vitamin D significantly increased total bone mineral density compared with the control group fed a normal diet or the group with no treatment [effect size = 0.479, 95% CI = 0.101 to 0.858 and effect size = 0.570, 95% CI = 0.196 to 0.945, respectively).

The investigators concluded the combination of vitamin K and D supplement increases the total bone mineral density (BMD) and decreases levels of undercarboxylated osteocalcin and a more favorable effect is expected when less than 500 μg/d vitamin K2 is used.

Original title:
The combination effect of vitamin K and vitamin D on human bone quality: a meta-analysis of randomized controlled trials by Kuang X, Liu C, […], Li D.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32219282

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

Undercarboxylated osteocalcin represents inadequately carboxylated osteocalcin and this fraction increases with vitamin K insufficiency.

Objectives:
Is there a causal relationship between dietary intake of dairy products and a positive effect on bone mineral density (BMD) in healthy postmenopausal women?

Study design:
This review article included 6 RCTs with a total of 618 participants. Milk was the main dairy product used in the trials.

Results and conclusions:
The investigators found there was a significant association between dairy product consumption and bone mineral density of the lumbar spine [SMD = 0.21, 95% CI = 0.05 to 0.37, p = 0.009], femoral neck [SMD = 0.36, 95% CI = 0.19 to 0.53, p  0.001], total hip [SMD = 0.37, 95% CI = 0.20 to 0.55, p  0.001] and total body [SMD = 0.58, 95% CI = 0.39 to 0.77, p  0.001].

The investigators found subgroup analysis showed a positive effect of dairy product consumption on the bone mineral density of the total hip starting from 12 months and the femoral neck starting from 18 months. There was also a positive association with the bone mineral density in the 4 sites in people living in low-calcium intake countries.

The investigators concluded that there is a causal relationship between dietary intake of dairy products, particularly milk during at least 12 months and a positive effect on bone mineral density (BMD) in healthy postmenopausal women. Therefore, dairy product consumption should be considered an effective public health measure to prevent osteoporosis in postmenopausal women.

Original title:
Effects of dairy products on bone mineral density in healthy postmenopausal women: a systematic review and meta-analysis of randomized controlled trials by Shi Y, Zhan Y, [...], Jiang Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32185512

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Find more information/studies on dairy products and elderly right here.

Menopause is the point when a woman no longer has menstrual periods for at least 12 months. Postmenopause is the stage after menopause.

Objectives:
Does a high LDL cholesterol level (bad cholesterol) increase risk of Alzheimer's disease (AD)?

Study design:
This review article included 26 case-control studies involving 7,033 participants (2,266 Alzheimer's disease patients and 4,767 non-dementia controls).

There was no significant evidence of publication bias according to the results of Egger's test [p = 0.084].

Results and conclusions:
The investigators found results from the meta-analysis of 26 studies revealed higher levels of LDL cholesterol (>121 mg/dL) in Alzheimer's disease than that of non-dementia controls [SMD = 0.35, 95% CI = 0.12 to 0.58, p 0.01], which was consistent with the results of the fixed-effect model [SMD = 0.16, 95% CI = 0.10 to 0.22, p 0.01].
Sensitivity analyses showed that no single study exerted substantial influence on the pooled effect size after sequentially omitting a study.

The investigators found subgroup analysis of age showed LDL cholesterol levels in Alzheimer's disease patients aged 60-70 were higher than that of non-dementia [60 ≤ age 70: SMD = 0.80, 95% CI = 0.23 to 1.37, p 0.01].  

The investigators concluded that elevated concentration of LDL cholesterol (>121 mg/dL) is a risk factor for Alzheimer's disease. This strong association is significant in patients with Alzheimer's disease aged 60-70 years, but vanishes with increasing age. This review article provides a promising strategy for reducing the risk of Alzheimer's disease in patients with hyperlipidemia, which may be achieved by regulating LDL cholesterol concentration between 103.9 and 121 mg/dL with statins. Prospective studies that exclude potential confounders, more scientific design and adequate long-term follow-up are needed to validate this hypothesis.

Original title:
Low-Density Lipoprotein Cholesterol and Alzheimer's Disease: A Systematic Review and Meta-Analysis by Zhou Z, Liang Y, […], Zhao M.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002548/

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Find more information/studies on cholesterol and Alzheimer's disease right here.
 

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:
Several epidemiological studies have been performed to evaluate the association of dietary intake of vitamin C-oriented foods (DIVCF) with risk of fracture and bone mineral density (BMD) loss, but the results remain controversial. Therefore, this review article has been conducted.

Does dietary intake of vitamin C-oriented foods decrease risk of fracture and bone mineral density loss?

Study design:
This review article included 4 cohort studies, 11 case-control studies and 2 cross-sectional studies with a total of 19,484 subjects.

The studies received a quality score of ≥5, indicating that the methodological quality of the studies was generally good.

No evidence of publication bias was found in the evaluation of dietary intake of vitamin C-oriented foods and the risk of hip fracture.

Results and conclusions:
The investigators found that the people with a higher dietary intake of vitamin C-oriented foods had a significantly 34% [RR = 0.66, 95% CI = 0.47 to 0.94, I2 = 79.5%, p = 0.000] lower risk of hip fracture.

The investigators found that the people with a higher dietary intake of vitamin C-oriented foods had a significantly 42% [RR = 0.58, 95% CI = 0.38 to 0.89] lower risk of hip fracture in case-control studies.
However, this reduced risk was not significant in cohort studies [RR = 0.92, 95% CI = 0.59 to 1.44]. 

The investigators found that the people with a higher dietary intake of vitamin C-oriented foods had a significantly 34% [RR = 0.66, 95% CI = 0.48 to 0.92] lower risk of osteoporosis.

The investigators found higher dietary intake of vitamin C-oriented foods was negatively associated with the risk of bone mineral density loss at the lumbar spine [pooled r = 0.15, 95% CI = 0.09 to 0.23] and at the femoral neck [pooled r = 0.20, 95% CI = 0.11 to 0.34].

The investigators concluded that higher dietary intake of vitamin C-oriented foods reduces the risk of hip fracture, osteoporosis and bone mineral density loss, suggesting that people should consume more vitamin C to decrease the risk of hip fracture, osteoporosis and bone mineral density loss, particularly lumbar spine and femoral neck.

Original title:
Can Dietary Intake of Vitamin C-Oriented Foods Reduce the Risk of Osteoporosis, Fracture, and BMD Loss? Systematic Review With Meta-Analyses of Recent Studies by Zeng LF, Luo MH, […], Liu J.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7008177/

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

Objectives:
Current evidence on associations between intakes of linoleic acid (LA), the predominant n-6 (ω-6) fatty acid and mortality is inconsistent and has not been summarized by a systematic review and meta-analysis. Therefore, this review article has been conducted.

Does higher linoleic acid intake, assessed by dietary surveys or biomarkers decrease mortality from all causes, cardiovascular disease (CVD) and cancer?

Study design:
This review article included 44 prospective cohort studies with 811,069 participants with dietary intake assessment (170,076 all-cause, 50,786 cardiovascular disease and 59,684 cancer deaths) and 65,411 participants with biomarker measurements (9,758 all-cause, 6,492 cardiovascular disease and 1,719 cancer deaths).

Meta-regressions suggested baseline age and dietary assessment methods as potential sources of heterogeneity for the association between linoleic acid and total mortality.

Results and conclusions:
The investigators found when compared with the lowest categories of dietary linoleic acid intake, that the highest categories of dietary linoleic acid intake significantly reduced total mortality risk with 13% [pooled RR = 0.87, 95% CI = 0.81 to 0.94, I2 = 67.9%].

The investigators found when compared with the lowest categories of dietary linoleic acid intake, that the highest categories of dietary linoleic acid intake significantly reduced cardiovascular disease mortality risk with 13% [pooled RR = 0.87, 95% CI = 0.82 to 0.92, I2 = 3.7%].

The investigators found when compared with the lowest categories of dietary linoleic acid intake, that the highest categories of dietary linoleic acid intake significantly reduced cancer mortality risk with 11% [pooled RR = 0.89, 95% CI = 0.85 to 0.93, I2 = 0%].

The investigators found for each standard deviation increment in linoleic acid concentrations in adipose tissue/blood compartments a significantly reduced total mortality risk of 9% [pooled RR = 0.91, 95% CI = 0.87 to 0.95, I2 = 64.1%].

The investigators found for each standard deviation increment in linoleic acid concentrations in adipose tissue/blood compartments a significantly reduced cardiovascular disease mortality risk of 11% [pooled RR = 0.89, 95% CI = 0.85 to 0.94, I2 = 28.9%].

The investigators found for each standard deviation increment in linoleic acid concentrations in adipose tissue/blood compartments a significantly reduced cancer mortality risk of 9% [pooled RR = 0.91, 95% CI = 0.84 to 0.98, I2 = 26.3%].

The investigators concluded higher linoleic acid intake, assessed by dietary surveys or biomarkers, reduces risk of mortality from all causes, cardiovascular disease and cancer. These data support the potential long-term benefits of PUFA intake in lowering the risk of cardiovascular disease and premature death.

Original title:
Dietary intake and biomarkers of linoleic acid and mortality: systematic review and meta-analysis of prospective cohort studies by Li J, Guasch-Ferré M, […], Hu FB.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/32020162

Additional information of El Mondo:
Find more information/studies on linoleic acid intake and mortality right here.
Linoleic acid is a PUFA.
 

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 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:
Alzheimer's disease (AD) is a common type of dementia, which has caused heavy global economic and health burden and the using of statins to treat Alzheimer disease has caused widely debated. Therefore, this review article has been conducted.

Does statin use decrease Alzheimer disease?

Study design:
This review article included a total of 9 RCTs containing 1,489 patients. Of them, 742 patients in the statins group, 747 patients in the control group (group without statins).

There were 9 studies used the MMSE scale, 5 studies used the ADAS-Cog scale, 4 studies used the NPI scale and 6 studies used the ADL scale.

Sensitivity analysis and publication bias test were both negative and the results were relatively reliable and stable.

Results and conclusions:
The investigators found meta-analysis of the 9 studies that reported the MMSE scale scores indicated that there was no significant effect of statins as compared with control group [pooled WMD = 1.09, 95% CI = -0.00 to 2.18, p = 0.05, I2 = 87.9%].

The investigators found meta-analysis of the 5 studies that reported the ADAS-Cog scale scores also indicated that there was no significant effect of statins as compared with control group [pooled WMD = -0.16, 95% CI = -2.67 to 2.36, p = 0.90, I2 = 80.1%].

The investigators found meta-analysis of the 4 studies that reported the NPI scale scores indicated that treatment with statins significantly slowed the rise in the NPI scale scores as compared with control group [pooled WMD = -1.16, 95% CI = -1.88 to -0.44, p = 0.002, I2 = 45.4%].

The investigators found meta-analysis of the 6 studies that reported the ADL scale scores indicated that treatment with statins significantly improve patients' daily living ability [pooled WMD = -4.06, 95% CI = -6.88 to -1.24, p = 0.005, I2 = 86.7%].

The investigators found results of subgroup analysis indicated that the use of statins in the short term (≤ 12 months) associated with the change of the MMSE scale scores [pooled WMD = 1.78, 95% CI = 0.53 to 3.04, p = 0.005, I2 = 79.6%].

The investigators concluded statins used in Alzheimer disease patients have beneficial effects on the scores of MMSE scale in the short term (≤ 12 months) and statins slow the deterioration of neuropsychiatric status and improve activities of daily living ability in Alzheimer disease patients.

Original title:
The efficacy of statins in the treatment of Alzheimer's disease: a meta-analysis of randomized controlled trial by Xuan K, Zhao T, […], Sun Y.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31930449

Additional information of El Mondo:
Find more information/studies on dementia right here.
 

Objectives:
Despite growing evidence for the association between other dietary macronutrients and bone health, limited and inconsistent knowledge is available regarding carbohydrate intake. Therefore, this review article has been conducted.

Does a high carbohydrate intake increase risk of fracture?

Study design:
This review article included observational studies.

Results and conclusions:
The investigators found no association between carbohydrate intake and the risk of fracture in high versus low intake meta-analysis [overall relative risk = 1.24, 95% CI = 0.84 to 1.84, p = 0.27, I2 = 57.7%, p = 0.05].

The investigators found, moreover, there was no relationship between carbohydrate intake and the risk of fracture in both linear [overall RR = 1.00, 95% CI = 0.94 to 1.05, p = 0.88, I2 = 68.1%, p = 0.48] and nonlinear [p non-linearity = 0.14] models.

The investigators concluded high carbohydrate intake does not increase risk of fracture.

Original title:
Dietary carbohydrate intake and risk of bone fracture: a systematic review and meta-analysis of observational studies by Mozaffari H, Daneshzad E and Azadbakht L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31982636

Additional information of El Mondo:
Find more information/studies on carbohydrates and elderly right here.
 

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

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Find here more information/studies about chronic diseases.
 

Objectives:
Which factors increase risk of dementia?

Study design:
This review article included 34 prospective cohort studies, among which 24 were eligible for meta-analysis. A total of 159,594 non-demented adults were enrolled at baseline before 65 years and 13,540 people were diagnosed with dementia after follow-up.

Results and conclusions:
The investigators found obesity significantly increased risk of dementia with 78% [RR = 1.78, 95% CI = 1.31-2.41].

The investigators found diabetes mellitus significantly increased risk of dementia with 69% [RR = 1.69, 95% CI = 1.38-2.07].

The investigators found current smoking significantly increased risk of dementia with 61% [RR = 1.61, 95% CI = 1.32-1.95].

The investigators found hypercholesterolemia significantly increased risk of dementia with 57% [RR = 1.57, 95% CI = 1.19-2.07].
However, the sensitivity analyses showed that the result of hypercholesterolemia was not reliable, which need to be confirmed by more high-quality studies.

The investigators found hypertension significantly increased risk of dementia with 41% [RR = 1.41, 95% CI = 1.23-1.62] for borderline blood pressure.

The investigators found hypertension significantly increased risk of dementia with 72% [RR = 1.72, 95% CI = 1.25-2.37] for high systolic blood pressure.
However, the sensitivity analyses showed that the result of high systolic blood pressure was not reliable, which need to be confirmed by more high-quality studies.

The investigators found hyperhomocysteinemia, psychological stress and heavy drinking were also associated with elevated dementia risk.

The investigators found, in addition, physical exercise, a healthy diet and hormone therapy in middle age were associated with the reduction of dementia risk.

The investigators concluded middle-aged people with obesity or diabetes and current smokers in midlife are at higher risk of developing dementia later in life.

Original title:
Midlife Modifiable Risk Factors for Dementia: A Systematic Review and Meta-analysis of 34 Prospective Cohort Studies by Li XY, Zhang M, [...], Tan L.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31902364

Additional information of El Mondo:
Find more information/studies on obesity, diabetes, hypertension and dementia right here.
 

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:
Can the biomarker miRNAs predict Alzheimer's disease?

Study design:
This review article included 10 studies containing 770 Alzheimer's disease and 664 normal controls (persons without Alzheimer's disease).

Results and conclusions:
The investigators found miRNAs presented excellent diagnostic performance and the overall sensitivity was 0.80 [95% CI = 0.75-0.83], specificity was 0.83 [95% CI = 0.78-0.87] and diagnostic odds ratio was 14 [95% CI = 11-19].

The investigators found subgroup analysis suggested that the Caucasian group and blood group showed a better performance in Alzheimer's disease diagnosis and the diagnostic odds ratio was 42 and 34, respectively.

The investigators concluded that miRNAs may be a promising biomarker for Alzheimer's disease.

Original title:
Blood circulating miRNAs as biomarkers of Alzheimer's disease: a systematic review and meta-analysis by Zhang YH, Bai SF and Yan JQ.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31385521

Additional information of El Mondo:
Find more information/studies on dementia and elderly.

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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Objectives:
Does alcohol consumption increase of risk of osteoporosis?

Study design:
This review article included  3 case control studies, 2 cohort studies and 1 cross-sectional study.

Results and conclusions:
The investigators found no association between consuming 0.5-1 drinks per day and the risk of developing osteoporosis [adjusted RR = 1.38, 95% CI = 0.90-2.12].
No association because RR of 1 was found in the 95% CI of 0.90 to 2.12. RR of 1 means no risk/association.

The investigators found compared with abstainers of alcohol, persons consuming 1-2 drinks per day had 1.34 times the risk of developing osteoporosis [adjusted RR = 1.34, 95% CI = 1.11-1.62].

The investigators found compared with abstainers of alcohol, persons consuming 2 drinks or more per day had 1.63 times the risk of developing osteoporosis [adjusted RR = 1.63, 95% CI = 1.01-2.65].

The investigators found a positive association between alcohol consumption and osteoporosis in the case-control studies [adjusted OR = 2.95, 95% CI = 1.78-4.90].

The investigators concluded there is a positive relationship between alcohol consumption, particularly 1 drink or more per day and osteoporosis.

Original title:
The effect of alcohol on osteoporosis: A systematic review and meta-analysis by Cheraghi Z, Doosti-Irani A, Almasi-Hashiani A, […], Mansournia MA.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/30844616

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Objectives:
Do older adults benefit from high protein intake (>0.8 g/kg body weight/day)?

Study design:
This review article included 12 cohort studies and 1 RCT.
Studies had an intervention duration of at least 6 months.

Results and conclusions:
The investigators found meta-analysis of the cohort studies showed that high vs low protein intake resulted in a statistically significant decrease of 11% for hip fractures [pooled HR = 0.89, 95% CI = 0.84 to 0.94, p 0.001, I2 = 0.0%, p = 0.614].
Sensitivity analyses showed that there was no single study affecting the overall estimate considerably.

The investigators concluded there is an association between a dietary protein intake above the current RDA of 0.8 g/kg body weight/day and a reduced hip fracture risk in older adults. In comparison with younger adults, the body of evidence from the included studies is not strong enough to increase the protein recommendation for older adults with respect to bone health.

Original title:
High Versus low Dietary Protein Intake and Bone Health in Older Adults: a Systematic Review and Meta-Analysis by Groenendijk I, den Boeft L , [...], de Groot LCPGM.

Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6704341/

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A protein intake higher than 0.8 g/kg body weight/day corresponds to a diet with a minimum of 11 En% protein. The easiest way to follow a diet with at least 11 En% protein is to choose only products that contain at least 11 En% protein. These products from the supermarket contain at least 11% En% protein.
 

Objectives:
Do low folate levels and vitamin B12 levels increase risk of depression among the aged people?

Study design:
This review article included both gender data of 11 folate-related (7,949 individuals) and 9 B12-related studies (6,308 individuals) and gender-specific data of 4 folate-related (3,409 individuals) and 3 B12-related studies (1,934 individuals).

Results and conclusions:
The investigators found low folate levels significantly increased risk of depression among the aged people with 23% [OR =1.23, 95% CI =1.07-1.43]. 

The investigators found low vitamin B12 levels significantly increased risk of depression among the aged people with 20% [OR =1.20, 95% CI =1.02-1.42]. 

The investigators found in subgroup analysis low vitamin B12 levels significantly increased risk of depression among the aged women with 33% [OR =1.33, 95% CI =1.02-1.74]. 

The investigators concluded both low folate levels and low vitamin B12 levels increase risk of depression among the aged people.

Original title:
Folate and B12 serum levels in association with depression in the aged: a systematic review and meta-analysis by Petridou ET, Kousoulis AA, [...], Stefanadis C.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/26055921

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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

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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

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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

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Find here more information/studies about omega-3 fatty acids and kidney disease.  
 

Objectives:
Findings from observational studies and clinical trials on the associations between vitamin E and dementia remain controversial. Therefore, this review article has been conducted.

Do low vitamin E levels increase risk of Alzheimer's disease (AD) or age-related cognitive deficits and mild cognitive impairment (MCI)?

Study design:
This review article included 31 studies.

Results and conclusions:
The investigators found individuals with Alzheimer's disease had lower circulatory concentrations of α-tocopherol (vitamin E) compared with healthy controls [SMD = -0.97, 95% CI = -1.27 to -0.68, p  0.00001].

The investigators found individuals with age-related cognitive deficits had lower circulatory concentrations of α-tocopherol (vitamin E) compared with healthy controls [SMD = -0.72, 95% CI = -1.12 to -0.32, p  0.0005].

The investigators found individuals with mild cognitive impairment had lower circulatory concentrations of α-tocopherol (vitamin E) compared with healthy controls [SMD = -0.72, 95% CI = -1.12 to -0.32, p  0.0005].

The investigators found levels of β-, γ- and δ-tocopherols did not significantly differ between groups of Alzheimer's disease and age-related cognitive deficits compared to controls.

The investigators concluded that lower α-tocopherol (vitamin E) levels have a strong association with Alzheimer's disease and mild cognitive impairment supporting evidence for the role of diet and vitamin E in Alzheimer's disease risk and age-related cognitive decline.

Original title:
A meta-analysis of peripheral tocopherol levels in age-related cognitive decline and Alzheimer's disease by Ashley S, Bradburn S and Murgatroyd C.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/31661399

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Objectives:
Serum uric acid (SUA) accounts for about 50% of extracellular antioxidant activity, suggesting that hyperuricemia (an abnormally high level of uric acid in the blood) may have a protective role in diseases characterized by high levels of oxidative stress, such as osteoporosis. Therefore, this review article has been conducted.

Does a high serum uric acid level (also called hyperuricemia) increase bone mineral density (BMD)?

Study design:
This review article included 19 cross-sectional studies with a total of 55,859 participants.

Results and conclusions:
The investigators found in 6 studies that subjects with higher serum uric acid levels had significantly higher bone mineral density values for the spine [SMD = 0.29, 95% CI = 0.22-0.35, I2 = 47%].
Simple correlation analyses substantially confirmed this finding.

The investigators found in 7 studies that subjects with higher serum uric acid levels had significantly higher bone mineral density values for total hip [SMD = 0.29, 95% CI = 0.24-0.34, I2 = 33%].
Simple correlation analyses substantially confirmed this finding.

The investigators found in 6 studies that subjects with higher serum uric acid levels had significantly higher bone mineral density values for femoral neck [SMD = 0.25, 95% CI = 0.16-0.34, I2 = 71%].
Simple correlation analyses substantially confirmed this finding.

The investigators found in 3 studies that an increase of one standard deviation in serum uric acid levels significantly reduced risk of new fractures with 17% [HR = 0.83, 95% CI = 0.74-0.92, I2 = 0%].

The investigators found no significant differences between men and women, although data about women were limited.

The investigators concluded a high serum uric acid level is independently associated with higher bone mineral density values and a lower risk of fractures, supporting a protective role for uric acid in bone metabolism disorders.

Original title:
Hyperuricemia protects against low bone mineral density, osteoporosis and fractures: a systematic review and meta-analysis by Veronese N, Carraro S, […], Cereda E.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/27636234

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