Risk factors for mortality in patients with diabetic foot infections: a prospective cohort study

Abstract

Background An increasing prevalence of diabetes mellitus has led to a high risk of diabetic foot infections (DFI) and associated morbidity. However, little is known about the relationship between DFI and mortality. Aim To investigate the risk of mortality and associated factors in patients with DFI in an Australian context. Methods A prospective cohort study of inpatients with DFI between May 2012 and October 2016 was done at Royal Darwin Hospital, a tertiary referral hospital for the Top End of the Northern Territory. Primary outcome was 1‐year mortality with Cox regression analysis undertaken to assess risk factors for mortality. Results Four hundred and thirteen consecutive adult diabetic patients with 737 admissions were referred to the High‐Risk Foot Service for DFI. Cumulative risk of mortality at 1 year was 8.9% (95% confidence interval (CI) 6.4–12.2). On univariable analysis, mortality was associated with older age (hazard ratio (HR) per year increase 1.08, 95% CI 1.06–1.11, P = 0.001), haemodialysis (HR 3.64, 1.74–7.62, P < 0.001), isolation of Pseudomonas aeruginosa (HR 2.32, 1.05–5.12, P = 0.04) and ischaemic heart disease (HR 2.05, 1.04–4.07, P = 0.04), while indigenous status (HR 0.48, 0.25–0.95, P = 0.04) and HbA1c > 7% (HR 0.45, 0.20–0.99, P < 0.05) were protective. After adjusting for confounders, independent risk factors for mortality were haemodialysis (adjusted HR 5.76, 95% CI 2.28–14.59, P < 0.001) and older age (adjusted HR 1.09, 1.06–1.13, P < 0.001). Patients on haemodialysis had a cumulative risk of mortality of 24.5% (95% CI 14.0–40.8) at 1 year. Conclusion There is a high risk of mortality associated with DFI, substantially increased in patients undergoing haemodialysis, highlighting the importance of early and dedicated interventions targeted at this high‐risk group.

Surgical wound dehiscence complicated by methicillin-resistant Staphylococcus aureus infection in a diabetic patient with femorotibial vascular bypass occlusion

“…7,8 The risk of mortality following admission of patients with diabetic foot infection is 8.9% in 1 year. 9 Probably in our patient, MRSA infection was also due to his previous hospitalisations that allowed selection and acquisition of antibiotic-resistant bacteria. 10 The presence of peripheral neuropathy allows the appearance of minor injuries, such as ingrown toenails, calluses, cuts, blisters and burns, to provide a strong incentive for the development of diabetic foot infections.…”

“…In particular, in accordance with the guidelines for diabetic foot infection, debridement of the wound was performed in a timely manner. 9 Daptomycin and rifampicin demonstrated to be the appropriate antibiotics to treat the MRSA wound infection within 2 weeks. Then, at home, daptomycin was switched to teicoplanin, another first-line anti-MRSA agent, to ensure the therapeutic continuity and avoid relapses.…”

Predictors of intra-hospital mortality in patients with diabetic foot ulcers in Nigeria: data from the MEDFUN Study.

“…Foryoung et al in Cameroon, Boyco et al in the US, Katz et al in Israel and Lynar et al in Australia reported similar ndings. 5,11,26,27 This nding may be explained by the fact that the prevalence of medical comorbidities that may lead to organ dysfunctions and death tend to increase with advancing age. Furthermore, micro and macrovascular diabetes complications are usually more life-threatening when they present in older than younger persons.…”

Predictors of intra-hospital mortality in patients with diabetic foot ulcers in Nigeria: data from the MEDFUN Study.

“…Foryoung et al from Cameroon, Boyco et al from the US, Katze from Israel and Lynar from Australia reported similar findings. 5,11,24,25 This finding may be explained by the fact that the prevalence of medical comorbidities that may lead to organ dysfunctions and death tend to increase with advancing age. Furthermore, micro and macrovascular diabetes complications are usually more life-threatening when they present in older than younger persons.…”