Type-D personality and ankle brachial index as predictors of impaired quality of life and depressive symptoms in peripheral arterial disease

Abstract

Background: Patient-based outcomes, such as impaired quality of life (QOL) and depression, may adversely affect the clinical course of patients with peripheral arterial disease (PAD). Disease severity indices, including the ankle brachial index, are only partially associated with these outcomes.

Objective: To examine whether individual differences in personality would predict impaired QOL and depression above and beyond PAD severity.

Design: A prospective follow-up study.

Setting: Vascular outpatient clinic of a teaching hospital.

Patients: Consecutive patients with newly diagnosed PAD (n = 150). Diagnosis and severity of PAD were based on history, physical examination, treadmill walking distance, and ankle brachial index. At their first visit, all patients completed the 14-Item Type-D Personality Scale, the World Health Organization Quality of Life Assessment Instrument-100, and the Center for Epidemiological Studies Depression Scale to assess distressed (type-D) personality, QOL, and depressive symptoms, respectively. The QOL and depression scales were repeated after 6 months' follow-up.

Main outcome measures: Impaired QOL and depressive symptoms at follow-up.

Results: Indices of PAD severity (ankle brachial index and walking distance) did not predict impaired QOL or depressive symptoms at follow-up. In contrast, type-D personality predicted poor physical health (odds ratio, 3.94; 95% confidence interval, 1.60-9.67; P = .003), decreased level of independence (odds ratio, 4.26; 95% confidence interval, 1.69-10.73; P = .002), and poor overall QOL (odds ratio, 4.72; 95% confidence interval, 1.73-12.88; P<.01) after controlling for age, sex, PAD severity, and cardiovascular risk factors. Type-D personality also independently predicted increased risk of depressive symptoms (odds ratio, 8.55; 95% confidence interval, 3.01-24.25; P<.001).

Conclusions: Type-D personality independently predicted individual differences in impaired QOL and depressive symptoms in patients with PAD above and beyond ankle brachial index. It is important to account for personality when evaluating patient-based outcomes in the context of PAD.