The prognostic impact of the functional status of patients with intermittent claudication is still obscure. From the lists of seven general practitioners, we identified all subjects aged 40-80 years (n = 4352). Of those reporting leg symptoms while walking on the Rose questionnaire (n = 760), 60 had a qualifying diagnosis of peripheral arterial disease (PAD). All of them received the Walking Impairment Questionnaire (WIQ). For each patient affected by PAD, three sex- and age-matched controls were selected randomly. After a 24-month follow-up, survival curves showed that PAD patients with WIQ scores > median had a higher cardiovascular risk than controls, and patients with WIQ scores < median had an even poorer prognosis (p < 0.001 for all WIQ domains). In PAD, after adjustment for age, sex, ankle-brachial index and comorbidity, two WIQ domains (ie walking speed and stair-climbing) were associated with cardiovascular events. The cardiovascular risk of claudicants who had a score > median for at least three WIQ domains was intermediate versus the risk of controls and PAD patients with a WIQ score < median, also when adjusted for the covariates indicated above (RR = 3.26, p = 0.019). In intermittent claudication, a worse functional status entails a greater risk of ischemic events versus low functional impairment.