Prin Vathesatogkit*, Sukit Yamwong*, Nongnuj Unkurapinun§, Piyamitr Sritara*, Supachai Tanomsup*

*Cardiology division, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Thailand
§Medical and Health Office, Electricity Generating Authority of Thailand, Thailand.

Background:
Lower socioeconomic status associates with all-cause mortality and cardiovascular outcome. Among traditional cardiovascular risk factors, hypertension seems to be the readily modifiable factor. We perform an analysis on effects of each socioeconomic parameter on prevalence of hypertension in a large 22-year cohort study from Thailand.

Objective:
To evaluate the association between socioeconomic status and prevalence of hypertension.

Method:
Participants from the EGAT study who completed the questionnaire, physical examination and blood tests in 1985 were enrolled (n=3,499). Baseline income, education, and occupation were considered as indicators of SES. Prevalence of hypertension in 1985, 1997, 2002 and 2007 surveys were analyzed separately. Statistical analyses were carried out using multiple logistic regression and Chi-square.

Result:
A cross-sectional model at 1985 survey showed lower prevalence of hypertension in university graduates 16.1% or those not progressing beyond primary school 27.7% (p=0.001). After adjusting for age, sex, diabetes, HDL- and LDL-cholesterol, BMI, smoking status, alcohol consumption and physical activity in 1985, education was an independent risk factor for prevalence of hypertension in 1997 (hazard ratio, HR 0.76 (95% confidence interval, CI: 0.57-0.99) and 2002 (HR 0.7 (95% CI: 0.54-0.92), comparing university graduates to those not. Income and occupational status is not an independent risk factor for hypertension outcome. In 2007, no socioeconomic parameter independently affects the prevalence of hypertension.

Conclusion:
Educational level is an independent predictor for prevalence of hypertension after adjusting for those metabolic risk factors. Income and occupation are not predictive for hypertension in the future.