A dietary intervention for chronic diabetic neuropathy pain: a randomized controlled pilot study

Abstract

Background:Diabetic neuropathy is a common and often debilitating condition for which available treatments are limited. Because a low-fat plant-based diet has been shown to improve glycemic control in individuals with type 2 diabetes, we hypothesized that such a diet would reduce painful symptoms of diabetic neuropathy.Methods:In this 20-week pilot study, individuals with type 2 diabetes and painful diabetic neuropathy were randomly assigned to two groups. The intervention group was asked to follow a low-fat, plant-based diet, with weekly classes for support in following the prescribed diet, and to take a vitamin B12 supplement. The control group was asked to take the same vitamin B12 supplement, but received no other intervention. At baseline, midpoint and 20 weeks, clinical, laboratory and questionnaire data were collected. Questionnaires included an analog ‘worst pain' scale, Michigan Neuropathy Screening Instrument, global impression scale, Short Form McGill Pain Questionnaire, Neuropathy Total Symptom Score, a weekly pain diary and Norfolk Quality of Life Questionnaire.Results:After 20 weeks, body weight change with the intervention was −6.4 kg (95% confidence interval (CI) −9.4 to −3.4, P<0.001) in an effect size analysis. Electrochemical skin conductance in the foot improved by an average of 12.4 microseimens (95% CI 1.2–23.6, P=0.03) with the intervention in an effect size analysis. The between-group difference in change in pain, as measured by the McGill pain questionnaire, was −8.2 points (95% CI −16.1 to −0.3, P=0.04). Michigan Neuropathy Screening Instrument questionnaire score change was −1.6 points (95% CI −3.0 to −0.2, P=0.03).Conclusions:Improvements were seen in some clinical and pain measures. This pilot study suggests the potential value of a plant-based diet intervention, including weekly support classes, for treating painful diabetic neuropathy.

A systematic review and meta‐analysis of nutrition interventions for chronic noncancer pain

“…After the removal of duplicates, a total of 7080 studies was identified in the search. Following full‐text screening, 71 studies were identified for inclusion, with 23 eligible for meta‐analysis. The abstracts for the majority of the papers were not sufficiently detailed to determine whether the full text should be retrieved.…”

“…Approximately 30% ( n = 21) of the studies were conducted in the USA , with five undertaken in Australia , four conducted in each of Germany , Japan and Spain , and three conducted in each of Denmark , Finland , Sweden , Iran and the Netherlands . Of the included studies, 47 were randomised controlled trials (RCT) , eight were nonrandomised trials , nine were pre–post studies , six were randomised cross‐over trials and one a longitudinal study .…”

“…Assessment of study quality rated 31 studies as of positive quality , 36 as neutral and four studies were classified as being of negative study quality . Of the 33 studies classified as neutral, information regarding the randomisation process ( n = 29) or the intervention description ( n = 13) was lacking.…”

“…The most common pain‐related condition experienced by study participants was rheumatoid arthritis ( n = 19 studies) , followed by osteoarthritis ( n = 16) and fibromyalgia ( n = 13) , migraine and chronic pain ( n = 4), joint pain , back pain , diabetic neuropathy ( n = 3), chronic pancreatitis , irritable bowel syndrome (IBS) , neuropathy and headache ( n = 1). Two studies had participants with two pain‐related conditions: rheumatoid arthritis and osteoarthritis and fibromyalgia and IBS .…”

“…Pain severity was explicitly stated as the primary outcome by 12 of the included studies . In addition to pain, 53 studies had several primary outcomes listed, including other disease‐related symptoms such as stiffness, tender and swollen joints, function, fatigue and blood biomarkers such as erythrocyte sedimentation rate and C‐reactive protein.…”