The role of socioeconomic status in hypertension

Socioeconomic status (SES) influences the epidemiology of hypertension from the molecular to the community level. Population studies of the Hypertension Detection and Follow-up Program (HDFP) in the 1970s demonstrated an inverse association between SES and the prevalence, severity, and prognosis of hypertension under conditions of (then) usual care in both blacks and whites. More recent studies have also demonstrated an inverse association of hypertension with SES, particularly in women with a major role for obesity. The hypertension-low SES relationship is accompanied by pre-clinical atherosclerosis as detected by carotid ultrasonography, left ventricular hypertrophy and by the aggregation of additional CVD risk factors among low SES hypertensives. The HDFP not only significantly reduced stroke incidence and all-cause mortality by step care, it also eliminated the inverse association between SES and mortality in both black and white hypertensives. Population levels of detection, treatment and control of hypertension have increased and national stroke mortality rates (CVA0MR), have declined markedly in the past 25 years. CVA mortality rates in 1962 increased stepwise and regularly with decreasing level of SES measures of the social environment of place of residence: for men ages 35-64, CVA-MR increased from 49 to in whites and from 137 to 297 in blacks; thus there was a six-fold higher CVA-MR for black men residing in low SES areas than white men in high SES places. CVA mortality rates declined 50-60% in the next 25 years among all groups, but the same step-wise six-fold mortality gradient by the SES of the social environment and ethnicity persisted at lower absolute levels of CVA-MR. Both individual and environmental social factors have been identified which affect the prognosis of hypertension, with potential for reduction in population levels of mortality and elimination of SES differences in prognosis by intervention and medical therapy. The challenge remains to develop the knowledge base and intervention strategies for the primary prevention of hypertension.