Identifying risk factors associated with infection in patients with chronic leg ulcers

Abstract

Leg ulcers are hard to heal. Infection causes delayed healing, negatively impacting patients' quality of life, the healthcare system, and society. Early recognition of patients at high risk of infection is essential to prevent complications and reduce negative impacts. However, at present, factors associated with infection in this population are not yet clearly understood. The study aimed to identify factors that were significantly associated with infection in chronic leg ulcers. A sample of 561 patients with chronic leg ulcers, who were previously recruited at outpatient clinics and community settings within Australia between 2008 and 2015, were selected for the current analysis. The prevalence of infection in the sample at study recruitment was 7.8%. A multivariate logistic regression model was used to identify factors associated with infection. The study identified 7 factors that were significantly independently associated with infection, including depression, chronic pulmonary disease, anti-coagulant use, calf ankle circumference ratio < 1.3, ulcer area ≥ 10 cm , slough in the wound bed tissue, and ulcers with heavy exudate. These findings could assist clinicians in the early recognition of patients at risk of infection and individualise treatment for these patients, thereby promoting wound healing.

Validation of predictive factors for infection in adults with chronic leg ulcers: A prospective longitudinal study

“…Depression was significantly associated with infection with the risk of infection increasing five times in those who were diagnosed with depression in a previous study of 561 patients with chronic leg ulcers (Bui, Edwards, et al, 2018a), and patients with CLUs who were also diagnosed with depression were three times more likely to have infection compared to those without depression in another study of 636 patients with chronic leg ulcers (Bui, Finlayson, et al, 2018b). In the current study, we found 15.6% of patients reported being diagnosed with depression.…”

“…While there could be a bidirectional relationship between depression and infection as patients with infection had a higher rate of depressive symptoms (Cancienne, Mahon, Dempsey, Miller, & Werner, ), depression has been identified as a risk factor for infection in general skin infections (Andersson et al, ) and in acute wounds (Cancienne et al, ; Olsen et al, ). Depression was significantly associated with infection with the risk of infection increasing five times in those who were diagnosed with depression in a previous study of 561 patients with chronic leg ulcers (Bui, Edwards, et al, ), and patients with CLUs who were also diagnosed with depression were three times more likely to have infection compared to those without depression in another study of 636 patients with chronic leg ulcers (Bui, Finlayson, et al, ). In the current study, we found 15.6% of patients reported being diagnosed with depression.…”

“…There was no significant correlation between these three factors. However, in previous studies, there were six other factors (depression, CPD, CAC <1.3, ulcer with slough tissue, ulcer area ≥10cm 2 and ulcer with heavy exudate level) found to be significantly associated with infected leg ulcers in multivariate tests (Bui, Edwards, et al, ; Bui, Finlayson, et al, ); thus, these factors were also included in a Cox regression model for the current study. However, as all patients with depression or CAC <1.3 in the current study were censored (as they did not have infection within 12 weeks), these variables were excluded from the Cox regression model.…”

“…Although these two studies were limited in design to a secondary data analysis, findings identified several risk factors for infection, which required further investigation (Bui, Edwards, et al, ; Bui, Finlayson, et al, ). These factors included physical and psychological factors (chronic pulmonary disease, depression, diabetes and use of walking aids) and lower‐limb factors (calf–ankle circumference ratio <1.3, ulcer with slough tissue, ulcer with an area ≥10 cm 2 and ulcer with heavy exudate; Bui, Edwards, et al, ; Bui, Finlayson, et al, ). There was a conflict of evidence with regard to wound duration, as it was found to be associated with colonisation of S. aureus (Tosh et al, ); however, three other studies did not confirm this relationship (Bui, Edwards, et al, ; Bui, Finlayson, et al, ; McInnes et al, ).…”

Adjuvant therapies in venous leg ulcer management: A scoping review

“…The natural history of VLU disease is a cycle of prolonged healing and recurrence . Factors that commonly contribute to poor healing include local causes, such as wound infection, tissue hypoxia, trauma, necrotic tissue as well as systemic diseases such as diabetes …”