Evaluating the effects of sedentary behaviour on plantar skin health in people with diabetes

BACKGROUND

Diabetes-Related Foot Ulcers (DRFUs) are a common and devastating consequence of Diabetes Mellitus and are associated with high morbidity, mortality, social and economic costs. Whilst peak plantar pressures during gait are implicated cited as a major contributory factor, DRFU occurrence has also been associated with increased periods of sedentary behaviour. The present study was designed aimed to assess the effects of sitting postures on plantar tissue health.

METHODS

After a period of acclimatisation, transcutaneous oxygen tensions (T_CPO₂) and inflammatory cytokines (IL-1α and IL-1RA) were measured at the dorsal and plantar aspects of the forefoot before, during and after a 20-min period of seated-weight-bearing in participants with diabetes (n = 11) and no diabetes (n = 10). Corresponding interface pressures at the plantar site were also measured.

RESULTS

During weight-bearing, participants with diabetes showed increases in tissue ischaemia which were linearly correlated proportional to plantar pressures (Pearson's r = 0.81; p < 0.05). Within the healthy group, no such correlation was evident (p > 0.05). There were also significant increases in post seated weight-bearing values for ratio for IL-1α and IL-1RA, normalised to total protein, post seated weight-bearing in participants with diabetes compared to healthy controls.

CONCLUSION

This study shows that prolonged sitting may be detrimental to plantar skin health. It highlights the need to further examine the effects of prolonged sitting in individuals, who may have a reduced tolerance to loading in the plantar skin and soft tissues.

Congestive heart failure presence predicts delayed healing of foot ulcers in diabetes: An audit from a multidisciplinary high-risk foot clinic

AIMS

This retrospective study aimed to investigate both established and less well-explored factors as potential predictive variables for failed and delayed ulcer healing.

METHODS

Patients with type 1 or 2 diabetes with foot ulceration presenting consecutively to, and then subsequently managed at, a multidisciplinary, high-risk foot clinic were followed until ulcer healing, amputation or death. Data comprised prospective standardised documentation at each visit and retrospective collection from hospital records, and included patient demographics, comorbidities, laboratory variables, and ulcer infection, depth and area at each presentation. Multiple regression analysis was used to determine independent predictors of failure to heal and delayed healing.

RESULTS

Of the 107 consecutive patients studied, 95 (89%) healed overall, 50 (47%) had healed in 12 weeks and the mean healing rate was a 10% decrease in ulcer area per week. Amongst all variables examined, comorbid congestive heart failure (CHF) was the only factor independently predictive of all measured outcomes of failure to heal overall, delayed healing at 12 weeks, and reduced healing rate. Ulcer infection at presentation, longer duration of antibiotic use, and liver enzyme abnormalities of raised ALT and AST:ALT<1 (each suggestive of non-alcoholic fatty liver disease), were also predictive of poor ulcer outcomes.

CONCLUSIONS

Comorbid congestive cardiac failure is predictive of delayed foot ulcer healing rate as well as a lower probability of healing overall. Liver enzyme abnormalities also predicted delayed ulcer healing outcomes. The mechanisms underlying these associations with foot ulcer outcomes in diabetes are unclear. Further studies are needed to determine the role of systematic routine documentation of heart failure and its severity, and then targeting of heart failure to potentially aid the management of foot ulcers in diabetes.

Topically applied connective tissue growth factor/CCN2 improves diabetic preclinical cutaneous wound healing: potential role for CTGF in human diabetic foot ulcer healing

AIMS/HYPOTHESIS

Topical application of CTGF/CCN2 to rodent diabetic and control wounds was examined. In parallel research, correlation of CTGF wound fluid levels with healing rate in human diabetic foot ulcers was undertaken.

METHODS

Full thickness cutaneous wounds in diabetic and nondiabetic control rats were treated topically with 1 μg rhCTGF or vehicle alone, on 2 consecutive days. Wound healing rate was observed on day 14 and wound sites were examined for breaking strength and granulation tissue. In the human study across 32 subjects, serial CTGF regulation was analyzed longitudinally in postdebridement diabetic wound fluid.

RESULTS

CTGF treated diabetic wounds had an accelerated closure rate compared with vehicle treated diabetic wounds. Healed skin withstood more strain before breaking in CTGF treated rat wounds. Granulation tissue from CTGF treatment in diabetic wounds showed collagen IV accumulation compared with nondiabetic animals. Wound α-smooth muscle actin was increased in CTGF treated diabetic wounds compared with untreated diabetic wounds, as was macrophage infiltration. Endogenous wound fluid CTGF protein rate of increase in human diabetic foot ulcers correlated positively with foot ulcer healing rate (r = 0.406; P < 0.001).

CONCLUSIONS/INTERPRETATION

These data collectively increasingly substantiate a functional role for CTGF in human diabetic foot ulcers.