Digest: Providing support for screening and strategic planning

I have commented on a couple of papers in the past regarding the Cinderella topic of peripheral painful neuropathy (PPN) and its treatment, which sadly is still a huge problem and often underreported or overlooked. A potentially exciting piece of research is about to be published in Diabetes Medicine looking at the relationship between vitamin D deficiency and PPN. Several studies have shown an association between vitamin D levels and diabetic peripheral neuropathy (DPP), however, none of these had differentiated between DPP and PPN, or accounted for seasonal sunlight exposure, daily activity and nerve fibre density. This study was designed to address these among other factors. Forty-five subjects were recruited with type 2 diabetes: 17 with PPN, 14 with DPP and 14 without peripheral neuropathy (HC). All subjects had seasonal sunlight exposure and daily activity measured, underwent a lower-limb skin biopsy and 25-hydroxyvitamin D levels measured between July and September. After adjusting for age, BMI, activity score and sunlight exposure, 25-hydroxyvitamin D levels were significantly lower in people with PPN compared with DPN and HC. Additionally, this also correlated with both lower cold detection thresholds (r=0.39, P=0.02) and subepidermal nerve density in PPN subjects. This paper, therefore, suggests there may be a causal link between Vitamin D deficiency and the pathogenesis of PPN. Although further studies are necessary, this could be very useful in preventative screening going forward. 
The second paper that I want to draw your attention to is from the Scottish Diabetes Research Network group. Its aim was to investigate amputation-free survival in those categorised as being high-risk for diabetic foot ulceration. Additionally, to compare three different groups within this cohort of patients, namely those with no previous ulcer, those with an active ulcer or those with a healed previous ulcer, anyone with previous minor or major amputation were excluded from the cohort. 
In all, 17,353 subjects were identified and included from the Scotland-wide diabetes register — SCi Di (n=247,278) between 2008 and 2011 with a 2-year follow up for each subject. The 2-year amputation-free survival rate in all high-risk foot subjects was 84.5% with 10% undergoing amputation (n=270), however, the paper does not distinguish between major and minor amputations in this figure. 
Unsurprisingly, active and healed ulcers subjects had significantly lower 2-year amputation-free survival compared with ulcer-free subjects (P<0.0001). A shorter amputation-free time was also shown for subjects who were older, male, had longer duration of diabetes, higher HbA_1c level, a history of cardiovascular disease and an eGFR lower than 30 ml/min/1.73m². One-in-four healed ulcer subjects died within 2 years, compared with one in eight for ulcer-free subjects. Mortality in those who underwent amputation was 90% within the 2-year period and was 22.8%, 16% and 12.1%, those with healed, active or no ulcers, respectively. This paper shows the value of population-based data collection and is useful for strategic planning and service reviews.