Socioeconomic status, John Henryism, and blood pressure in black adults. The Pitt County Study

The joint influence of socioeconomic status and John Henryism on blood pressure was examined in a probability sample of 1,784 black adults aged 25-50 years in Pitt County, North Carolina, in 1988. John Henryism was measured by means of the John Henryism Active Coping Scale. Socioeconomic status (low, medium, and high) was based on respondents' education and occupation. Prior research indicated that, for blacks, the inverse association between socioeconomic status and hypertension may be stronger for individuals who score high in John Henryism. In this more urban sample of blacks, the hypothesized interaction achieved modest statistical support (p less than 0.08) only for hypertension prevalence. For individuals with high levels of John Henryism, adjusted prevalences declined with increasing socioeconomic status (29.4%, 26.2%, and 20.5% for low, medium, and high socioeconomic status, respectively); for individuals with low levels of John Henryism, hypertension prevalence was similar in the low (22.6%) and medium (22.8%) socioeconomic categories but higher in the high socioeconomic category (25.9%). Elevated psychological stress in white-collar workers was probably responsible for the nonsignificant inverse gradients between socioeconomic status and mean blood pressures and for the weak interaction between socioeconomic status and John Henryism with regard to hypertension prevalence.