Tracking of Blood Pressure Among Adolescents and Young Adults in an Urban Slum of Puducherry

BACKGROUND: Early diagnosis of hypertension (HT) is an important strategy in its control. Tracking of blood pressure (BP) has been found useful in identifying persons with potential HT, particularly in youngsters. A cohort of 756 subjects (with baseline information as a cross-sectional study in 2002) was followed up in 2006 to comment on the distribution of BP and its attributes. OBJECTIVES: To track BP distribution in a cohort of adolescents and young adults, and assess the persistence of high/low normotensives; to measure the incidence of HT and study the relationship of BP with age, sex, socioeconomic status, BMI, physical exercise, salt intake, smoking and alcohol consumption. MATERIALS AND METHODS: The baseline study cohort (2002) of 756 subjects (19-24 years) in urban field area of Department of Preventive and Social Medicine, JIPMER, was followed up between May and November 2006 by house visits for measurement of sociodemographic variables, anthropometry, salt intake, physical activity and BP. RESULTS: A total of 555 subjects from the 2002 cohort were contacted (73.4%), in that 54.5% subjects who were below 5(th) percentile, 93.6% subjects between 5(th) and 95(th) percentiles and 72% of those above 95(th) percentile previously persisted in the same cut-offs for systolic blood pressure (SBP). The corresponding figures for diastolic blood pressure (DBP) were 46.2, 92.2 and 74.1%, respectively. Shift from one cut-off to another was not significant for both SBP and DBP, proving the tracking phenomenon. Annual incidence of HT was 9.8/1000. Baseline BP was the significant predictor of current BP for the entire cohort; BMI and salt intake were significant predictors only in certain sections of the study cohort. CONCLUSIONS: Early diagnosis of hypertension even among adolescents/young adults is an important preventive measure, as tracking exists in the population.