A retrospective cohort study on diabetic foot disease: ascertainment of ulcer locations by age group

A retrospective cohort study on diabetic foot disease: ascertainment of ulcer locations by age group

REVIEWED BY Donna Oomens, AFASA | ASA SIG: Vascular

REFERENCE | Authors: Patrícia Rosinha, Miguel Saraiva, Lia Ferreira, Susana Garrido, André Carvalho, Cláudia Freitas, Cláudia Amaral, Luís Costa, Luís Loureiro, Rui Carvalho

WHY THIS STUDY WAS PERFORMED

There has been a worldwide increase in both average life expectancy and diabetes mellitus (DM). Therefore, there is an associated increase of diabetic foot ulcers, a major complication of DM. Diabetic foot ulcers carry both an increased risk of mortality and decreased quality of life. Advanced age has been previously shown to be associated with increased severity of diabetic foot ulcers, potentially due to the limited mobility and functional disability resulting from loss of muscle mass and function. The site of a diabetic foot ulcer has also been shown to be an independent predictor of healing.

This study aimed at evaluating the role that location and age play in the healing of diabetic foot ulcers to better understand the prognosis within different age groups.

HOW THE STUDY WAS UNDERTAKEN

This was a retrospective, observational study at a single centre. Initially, 583 patients were recruited; however, after exclusion criteria (no active ulcer or incomplete clinical data) was applied, there were 435 patients remaining.

The cohort was divided by age into two groups: younger adults 18–64 years (YA) and older adults > 64 years (OA). The location of the ulcer was assessed using anatomical descriptors (forefoot, mid foot or above, plantar, non-plantar, right and left) and three different published ulcer classifications (PEDIS/Infectious Diseases Society of America, University of Texas system and Wagner’s classification). Clinical factors such as history of smoking, presence of elevated HbA1c, insulin requirement, dyslipidaemia or hypertension were also included in the statistical analysis.

“Plantar and distal regions of the foot are more prone to trauma and therefore enable an easier ‘gateway’ for infectious agents.”

WHAT THE STUDY FOUND

The younger group had a higher percentage of men and smokers, while Type 2 diabetes was more common in the older group, most of which is expected. The older group also had increased comorbidities such as dyslipidaemia and hypertension. There was no significant difference (p < 0.05) in terms of evolution time, antibiotic therapy or laterisation. Also, there was no significant difference between groups for number (p = 0.301) or type (p = 0.055) of amputation. The older group were prone to proximal/non-plantar locations, which have lower healing rates, and the authors suggest the need for individualised treatment plans to ensure the best outcomes.

THE RELEVANCE TO CLINICAL PRACTICE

Atherosclerosis is a potentially treatable contributing factor in diabetic foot ulcers leading to frequent referrals for arterial assessment in the elderly. Understanding that the location of ulcers can impact the risk of healing helps sonographers understand the importance of our role in correctly performing the ultrasound to provide the best healing outcome.

A troubling aside in the results is having a greater number of smokers in the younger adult group means that the anti-smoking message is not working in this age group. As this study was undertaken in Portugal, it may not be generalisable to the Australian context; however, serves as a reminder to us that we need to be vigilant in promoting an anti-smoking message to our patients.