A Single Shot of Vitamin D May Help Improve Diabetic Nerve Pain

Vitamin D for the treatment of painful diabetic neuropathy BMJ Open Diab Res Care 2016;4:e000148

What is the problem and what is known about it so far?

About half of all people with diabetes have some form of nerve damage. Nerve damage can cause shooting and burning pain in the feet or hands. It is more common in those who have had the disease for a number of years. New studies show that vitamin D may play an important role in treating painful diabetic nerve damage.

Why did the researchers do this particular study?

Researchers wanted to examine the link between vitamin D and diabetic neuropathy. Recently, a multinational study showed that 50% of the study subjects with type 2 diabetes were deficient for vitamin D.

Who was studied?

A total of 143 people with diabetes, mostly type 2 diabetes, were enrolled. Participants were ages 18 to 80 years old. The study took place at the Baqai Institute of Diabetology and Endocrinology in Karachi, Pakistan.

How was the study done?

Participants visited the institute five times over a 20-week period. A single injection of vitamin D (600,000 IU) was administered (under the skin into a muscle) at the first visit. At each visit patients were asked to rate their pain using pain score questionnaires, and their blood glucose, cholesterol, and other measurements were taken.

What did the researchers find?

By visit 3 (10 weeks after visit 1), there was a significant improvement in participants' diabetic nerve pain levels. When comparing data from visit 1 and visit 5, A1C (a measurement of blood glucose levels over time) was also reduced, and HDL (good) cholesterol levels were increased.

What were the limitations of the study?

The current study did not include a second group with similar characteristics who did not receive the treatment, called a placebo group, for comparison. Therefore, a longer placebo-controlled study with more frequent assessment of vitamin D levels is needed.

What are the implications of the study?

A single dose of 600,000 IU of vitamin D (injected under the skin into a muscle) appears to be a safe treatment for improving diabetic nerve pain, according to the findings from this study. The benefits of vitamin D appear to be best at 10 weeks after the dose is given and can last up to 20 weeks.