Reduced serum levels of folate and vitamin B12 increase peripheral neuropathy risk among patients with type 2 diabetes

Objectives:
The association between serum folate and vitamin B12 levels and the risk of diabetic peripheral neuropathy (DPN) remains unclear. Therefore, this review article (meta-analysis) has been conducted.

Do reduced serum levels of folate and vitamin B12 increase peripheral neuropathy risk among patients with type 2 diabetes?

Study design:
This review article included 16 studies of serum folate levels (1190 patients with diabetic peripheral neuropathy and 1501 patients without diabetic peripheral neuropathy) and 18 studies of serum vitamin B12 levels (1239 patients with diabetic peripheral neuropathy and 1562 patients without diabetic peripheral neuropathy) in patients with type 2 diabetes mellitus (T2DM).

Results and conclusions:
The investigators found reduced serum levels of folate in patients with type 2 diabetes and diabetic peripheral neuropathy compared with patients with type 2 diabetes but without diabetic peripheral neuropathy [WMD = -1.64, 95% CI = -2.46 to -0.81].
A subgroup analysis confirmed this association in the Chinese population, but not in the Caucasian and mixed populations.

The investigators found reduced serum levels of vitamin B12 in patients with type 2 diabetes and diabetic peripheral neuropathy compared with patients with type 2 diabetes but without diabetic peripheral neuropathy [WMD = -70.86, 95% CI = -101.55 to -40.17].
A subgroup analysis confirmed this association in the Chinese population, but not in the Caucasian and mixed populations.

The investigators concluded reduced serum levels of folate and vitamin B12 increase peripheral neuropathy risk among patients with type 2 diabetes. These findings support the need for further controlled studies in defined patient populations and the importance of monitoring serum folate and vitamin B12 levels in patients with type 2 diabetes.

Original title:
Serum folate, vitamin B12 levels and diabetic peripheral neuropathy in type 2 diabetes: A meta-analysis by Wang D, Zhai JX and Liu DW.

Link:
https://www.ncbi.nlm.nih.gov/pubmed/28081987

Additional information of El Mondo:
Find more information/studies on diabetes, folate and vitamin B12 right here.

Diabetic peripheral neuropathy is a long-term complication of diabetes. Exposure to high blood glucose levels over an extended period of time causes damage to the peripheral nerves; the nerves that go to the arms, hands, legs and feet. It is one of many complications associated with diabetes, with nearly 60 percent of diabetics having some form of nerve damage.