Premium
Risk factors for mortality in patients with diabetic foot infections: a prospective cohort study
Author(s) -
Lynar Sarah A.,
Robinson Claire H.,
Boutlis Craig S.,
Commons Robert J.
Publication year - 2019
Publication title -
internal medicine journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.596
H-Index - 70
eISSN - 1445-5994
pISSN - 1444-0903
DOI - 10.1111/imj.14184
Subject(s) - medicine , hazard ratio , prospective cohort study , proportional hazards model , diabetes mellitus , context (archaeology) , confidence interval , diabetic foot , risk of mortality , paleontology , biology , endocrinology
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.