In a population-based, cross-sectional study of 310 treated hypertensives (HT) and 288 matched normotensive controls (NT), social and biological variables were investigated.

HT comprised a higher proportion of individuals in lower socioeconomic strata (P<0.001) and lower social class distribution (defined by occupation and educational level) than NT.

However, lower estimated risks (odds ratios, OR) for hypertension were found in lower social strata than in higher ones for most biological variables.

This does not support the hypothesis of an increased general susceptibility in lower social classes to standard risk factors as a main factor behind the higher prevalence of hypertension, in as much as the ORs for most variables were not higher in the lower classes than in the higher ones.