Determinants of invasive treatment in lower extremity peripheral arterial disease

Abstract

Since it is unknown what factors are weighed in a clinician's decision to refer patients with symptomatic lower extremity peripheral arterial disease (PAD) for invasive treatment, we examined the relationship between health status, lesion location, and site variations and invasive treatment referral ≤1 year following diagnosis in patients with PAD. This was a prospective observational cohort study on ambulatory patients that presented themselves at two vascular surgery outpatient clinics. A total of 970 patients with new symptoms of PAD or with an exacerbation of existing PAD symptoms that required clinical evaluation and treatment (Rutherford Grade I) were eligible, 884 consented and were included between March 2006 and November 2010. We report on 505 patients in the current study. Prior to patients' initial PAD evaluation, the Short Form-12, Physical Component Scale (PCS) was administered to measure health status. Anatomical lesion location (proximal vs distal) was derived from duplex ultrasounds. PCS scores, lesion location, and site were evaluated as determinants of receiving invasive (endovascular, surgery) vs noninvasive treatment ≤1 year following diagnosis in Poisson regression analyses, adjusting for demographics, ankle-brachial index, and risk factors. Invasive treatment as a first-choice was offered to 167 (33%) patients. While an association between poorer health status and invasive therapy was found in unadjusted analyses (relative risk [RR], 0.98; 95% confidence interval [CI], 0.97-1.00; P = .011), proximal lesion location (RR, 3.66; 95% CI, 2.70-4.96; P < .0001) and site (RR, 1.69; 95% CI, 1.11-2.58; P = .014) were independent predictors of invasive treatment referral in the final model. One-third of patients were treated invasively following PAD diagnosis. Patients' health status was considered in providers' decision to refer patients for invasive treatment, but having a proximal lesion was the strongest predictor. This study also found some important first indications of site variations in offering invasive treatment among patients with PAD. Future work is needed to further document these variations in care.