Clinical Trial: Vitamin D Treatment for Painful Diabetic Neuropathy

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Vitamin D for the Treatment of Painful Diabetic Neuropathy

Brief Summary:

The main objective of the study is to assess the effect of vitamin D treatment on painful diabetic neuropathy in Pakistan.

This is a prospective study of diabetic patients with a DN score ≥ 4, administered a single dose of 600,000 IU of Vitamin D.

All diabetic patients (type 1 and type 2) at the screening visit were considered eligible to participate in the study. The change in painful diabetic neuropathy scores was assessed using DN4 Neuropathic Pain Diagnostic Questionnaire and SF - MPQ for all participants at each visit.


Detailed Summary:

Background Painful diabetic neuropathy (DPN) is common in patients with long-standing diabetes mellitus. The prevalence of neuropathy approaches 50% in those with diabetes for 25 years. Among patients with neuropathy, 11.6% with type 1 diabetes and 32.1% with type 2 diabetes have neuropathic pain. In our recent observational study of a large cohort of diabetic patients from primary care in northwest England (n = 15,692), painful diabetic neuropathy (PDN), assessed using the neuropathy symptom score (NSS) and neuropathy disability score (NDS) (NSS >/=5 and NDS >/=3) was 21%, and the prevalence of painful symptoms (NSS >/=5) was 34%. Despite less neuropathy in South Asians (14%) compared to Europeans (22%) (P < 0.0001), painful symptoms were greater in South Asians (38 vs. 32%, P < 0.0001) and they maintained a 50% increased risk of painful neuropathy symptoms (P < 0.0001).

The potential for an association between vitamin D and a beneficial effect on neuropathy is based on experimental data which has shown that vitamin D3 can upregulate NGF and the products of its neuronal target genes resulting in an improvement in experimental diabetic neuropathy. Vitamin D insufficiency has recently been associated with retinopathy and self-reported peripheral neuropathy symptoms even after adjusting for demographic factors, obesity, comorbidities, use of medications for neuropathy and diabetes duration and glycemic control. Of course, there may be some overlap between the symptoms associated with vitamin D deficiency and diabetic neuropathy, which may partly explain the excess painful symptoms we have observed in Asians, particularly as the latter have excess vitamin D deficiency.

The preliminary data suggests there is an urgent need to undertake a blinded placebo-controlled randomised trial of vitamin D3 in the treatme
Sponsor: Baqai Institute of Diabetology and Endocrinology

Current Primary Outcome: Improvement in painful diabetic neuropathy by the use of vitamin D Injections (600,000 IU) assessed with the DN4 Neuropathic Pain Diagnostic Questionnaire [ Time Frame: 5 months ]

DN4 Neuropathic Pain Diagnostic Questionnaire contains six questions which reflect positive symptoms for pain i.e. question 1, 2, 3, 4, 5 and 10 (sensations of burning, painful cold, electric shocks, tingling, pins & needles and brushing).


Original Primary Outcome: Same as current

Current Secondary Outcome: Improvement in painful diabetic neuropathy by the use of vitamin D Injections (600,000 IU) assessed with the SF-Mac Gill Pain Questionnaire. [ Time Frame: 5 months ]

SF-Mac Gill pain questionnaire was evaluated to establish the sensory dimensions of pain which included pain sensations like throbbing, shooting, stabbing, sharp, cramping, gnawing, hot burning, aching, heavy, tender and splitting and effective dimensions of the pain experience which included sensations like tiring-exhausting, sickening, fearful and punishing-cruel.


Original Secondary Outcome: Same as current

Information By: Baqai Institute of Diabetology and Endocrinology

Dates:
Date Received: February 1, 2016
Date Started: June 2012
Date Completion:
Last Updated: April 8, 2016
Last Verified: April 2016