Impact of psychological factors on objective ambulatory measures in patients with intermittent claudication

Objective The purpose of this study was to evaluate the difference in objective measures of ambulation and psychosocial factors in patients with intermittent claudication (IC) stratified by type D personality, which incorporates elements of social inhibition and negative affectivity. Methods During a 1-year period, routine history and physical examination, ankle-brachial index, and pulse volume recording were performed on IC patients. Questionnaires assessing type D personality and psychosocial factors were also collected. The 6-minute walk test (6MWT) was performed, assessing symptoms and distance walked. Univariate and multivariate methods were used to assess the association between ambulation and type D personality. Results Seventy-one patients were enrolled (mean age, 62.5 ± 1.1 years; mean ankle-brachial index, 0.55 ± 0.03). Mean distance to symptoms and total distance walked were 83.7 ± 80.1 m and 206.5 ± 126.3 m, respectively. Type D personality was present in 29.6% of the population (n = 21). On 6MWT, 83.1% of all patients developed symptoms, and 57.4% quit because of symptoms. Univariate analysis of objective measures of ambulation demonstrated lower distance to symptoms in the type D group and trends toward lower total distance walked and quitting the 6MWT. Multivariate models showed increased odds of quitting the 6MWT (odds ratio, 7.71; P  = .01) and less total distance walked by an average of 33.2 ± 13.3 m ( P  = .02) for the type D group. Conclusions Despite equivalent demographic, medical, and psychosocial factors, the type D group was limited in ambulation, suggesting that type D personality is a strong predictor of disease impact in patients with IC.