Tags

Type your tag names separated by a space and hit enter

Association of metformin, elevated homocysteine, and methylmalonic acid levels and clinically worsened diabetic peripheral neuropathy.
Diabetes Care. 2010 Jan; 33(1):156-61.DC

Abstract

OBJECTIVE

The severity of peripheral neuropathy in diabetic patients varies for unclear reasons. Long-term use of metformin is associated with malabsorption of vitamin B(12) (cobalamin [Cbl]) and elevated homocysteine (Hcy) and methylmalonic acid (MMA) levels, which may have deleterious effects on peripheral nerves. The intent of this study was to clarify the relationship among metformin exposure, levels of Cbl, Hcy, and MMA, and severity of peripheral neuropathy in diabetic patients. We hypothesized that metformin exposure would be associated with lower Cbl levels, elevated Hcy and MMA levels, and more severe peripheral neuropathy.

RESEARCH DESIGN AND METHODS

This was a prospective case-control study of patients with type 2 diabetes and concurrent symptomatic peripheral neuropathy, comparing those who had received >6 months of metformin therapy (n = 59) with those without metformin exposure (n = 63). Comparisons were made using clinical (Toronto Clinical Scoring System and Neuropathy Impairment Score), laboratory (serum Cbl, fasting Hcy, and fasting MMA), and electrophysiological measures (nerve conduction studies).

RESULTS

Metformin-treated patients had depressed Cbl levels and elevated fasting MMA and Hcy levels. Clinical and electrophysiological measures identified more severe peripheral neuropathy in these patients; the cumulative metformin dose correlated strongly with these clinical and paraclinical group differences.

CONCLUSIONS

Metformin exposure may be an iatrogenic cause for exacerbation of peripheral neuropathy in patients with type 2 diabetes. Interval screening for Cbl deficiency and systemic Cbl therapy should be considered upon initiation of, as well as during, metformin therapy to detect potential secondary causes of worsening peripheral neuropathy.

Authors+Show Affiliations

Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada. daryl.wile@albertahealthservices.caNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

19846797

Citation

Wile, Daryl J., and Cory Toth. "Association of Metformin, Elevated Homocysteine, and Methylmalonic Acid Levels and Clinically Worsened Diabetic Peripheral Neuropathy." Diabetes Care, vol. 33, no. 1, 2010, pp. 156-61.
Wile DJ, Toth C. Association of metformin, elevated homocysteine, and methylmalonic acid levels and clinically worsened diabetic peripheral neuropathy. Diabetes Care. 2010;33(1):156-61.
Wile, D. J., & Toth, C. (2010). Association of metformin, elevated homocysteine, and methylmalonic acid levels and clinically worsened diabetic peripheral neuropathy. Diabetes Care, 33(1), 156-61. https://doi.org/10.2337/dc09-0606
Wile DJ, Toth C. Association of Metformin, Elevated Homocysteine, and Methylmalonic Acid Levels and Clinically Worsened Diabetic Peripheral Neuropathy. Diabetes Care. 2010;33(1):156-61. PubMed PMID: 19846797.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Association of metformin, elevated homocysteine, and methylmalonic acid levels and clinically worsened diabetic peripheral neuropathy. AU - Wile,Daryl J, AU - Toth,Cory, Y1 - 2009/10/21/ PY - 2009/10/23/entrez PY - 2009/10/23/pubmed PY - 2010/3/20/medline SP - 156 EP - 61 JF - Diabetes care JO - Diabetes Care VL - 33 IS - 1 N2 - OBJECTIVE: The severity of peripheral neuropathy in diabetic patients varies for unclear reasons. Long-term use of metformin is associated with malabsorption of vitamin B(12) (cobalamin [Cbl]) and elevated homocysteine (Hcy) and methylmalonic acid (MMA) levels, which may have deleterious effects on peripheral nerves. The intent of this study was to clarify the relationship among metformin exposure, levels of Cbl, Hcy, and MMA, and severity of peripheral neuropathy in diabetic patients. We hypothesized that metformin exposure would be associated with lower Cbl levels, elevated Hcy and MMA levels, and more severe peripheral neuropathy. RESEARCH DESIGN AND METHODS: This was a prospective case-control study of patients with type 2 diabetes and concurrent symptomatic peripheral neuropathy, comparing those who had received >6 months of metformin therapy (n = 59) with those without metformin exposure (n = 63). Comparisons were made using clinical (Toronto Clinical Scoring System and Neuropathy Impairment Score), laboratory (serum Cbl, fasting Hcy, and fasting MMA), and electrophysiological measures (nerve conduction studies). RESULTS: Metformin-treated patients had depressed Cbl levels and elevated fasting MMA and Hcy levels. Clinical and electrophysiological measures identified more severe peripheral neuropathy in these patients; the cumulative metformin dose correlated strongly with these clinical and paraclinical group differences. CONCLUSIONS: Metformin exposure may be an iatrogenic cause for exacerbation of peripheral neuropathy in patients with type 2 diabetes. Interval screening for Cbl deficiency and systemic Cbl therapy should be considered upon initiation of, as well as during, metformin therapy to detect potential secondary causes of worsening peripheral neuropathy. SN - 1935-5548 UR - https://www.unboundmedicine.com/medline/citation/19846797/Association_of_metformin_elevated_homocysteine_and_methylmalonic_acid_levels_and_clinically_worsened_diabetic_peripheral_neuropathy_ L2 - http://care.diabetesjournals.org/cgi/pmidlookup?view=long&pmid=19846797 DB - PRIME DP - Unbound Medicine ER -