[Assessment of the prevalence of atherosclerotic lower limb arteriopathy in France as a systolic index in a vascular risk population]

Abstract

Objective: Obliterative arteriopathy of the lower limbs is a severe disease. History taking often underestimates prevalence. In studies using the Rose questionnaire and examining the prevalence of symptomatic arteriopathy defined by the presence of intermittent claudication, prevalence has been rather constant, around 2% in the general population in industrialized countries. A more clinical approach searching for physical anomalies (absence of distal pulse) generally gives higher rates. The most recent data led us to conduct a study focusing on screening for arterial disease using the systolic index (the systolic index is the ratio between the ankle and humeral systolic pressure). A systolic index below 0.90 would be a sign of defective perfusion, increasing in severity with poorly compensated arterial lesions.

Method: A survey was performed in a random sample of 150 practitioners using an allocation procedure to the nearest colleague in case of refusal. A data sheet containing demographic data and the main risk factors was established for each consulting patient aged from 40 to 80 years. The systolic index was measured in each patient with at least one vascular risk or who consulted for pain in the lower limbs. A simple sequential non-randomized patient recruitment scheme was used.

Results: The survey population included nearly 9,000 patients (8,987), 46% men and 54% women, mean age 64 years (table I). Patient risk factors including smoking, diabetes, hypertension, and physical exercise were adjusted for sex and age (table II-VI, IX). The systolic index was recorded in 41% of the population who had a vascular risk factor. Among these patients, nearly one-fourth had a systolic index under 0.90, giving a prevalence in the sample population of 11% (table VII). This rate was also assessed by age and sex (table VIII). Logistic regression evidenced a prognostic value (fig. 1) for smoking, hypertension and sedentary activity, and to a lesser extent, for age and sex. There was a significant difference by latitude, patients living in northern France having a higher risk than those living in southern France (table X). In addition, there was a relationship between the systolic index and spontaneous complaint, showing that this complaint is poorly specific for arterial disease (table XI, XII).

Conclusion: This epidemiological approach to arteriopathy implemented by general practitioners searching for patients with a vascular profile and measuring systolic index is a novel method. It gave an estimation of prevalence at 11% in the French population, a rate compatible with that reported by other international teams. The method also allowed an analysis of factors affecting the rate.