Leg blood flow and long-term cardiovascular prognosis in men with typical and atypical intermittent claudication

Abstract

Objectives: To compare leg blood flow and the long-term cardiovascular prognosis in men with typical and atypical intermittent claudication (IC) according to Rose's questionnaire. Methods: Leg blood flow during reactive hyperaemia was assessed at 55 years of age by calf plethysmography. Measurement of the systolic ankle-arm pressure index was used to assess the prevalence of peripheral arterial disease (PAD) at 68 years of age. Mortality and incidence of cardiac events is based on record linkage with regional and national registers. Results: Twenty-one (3%) out of 700 men had typical IC at 55 years of age. Sixteen (76%) of these had normal plethysmography, with a mean peak flow (95% CI) of 24.6 (19.3-30.0) ml/min/100 ml. Peak flows were similar and normal in men with atypical IC (mean 22.5; 95% CI 21.3-23.6) and men having no pain (mean 23.8; 95% CI 23.1-24.4). Mortality rates were increased in men with typical IC but who had normal leg blood flow (49.5 deaths/1000 person years; p = 0.008), and men having atypical IC (35.3 deaths/1000 person years; p =0.007) in comparison with men having no leg pain (27.4 deaths/1000 person years). This could not be accounted for by an increased cardiac event rate. The prevalence of PAD at 68 years of age was not increased in either of these two groups. Conclusions: Only 12% of subjects with exertional pain fulfilled all criteria for typical IC. Typical and atypical claudication in absence of objective evidence of PAD was associated with a reduced life expectancy, but not with an increased cardiovascular risk. To properly assess the prognosis, non-invasive assessment of PAD should be used in addition to questionnaires.