Community screening for high blood pressure among adults in urban and rural Papua New Guinea

Abstract

This is a cross-sectional study conducted intermittently in Port Moresby, the National Capital District of Papua New Guinea, from 1996 to 1997; Mt Obree in Central Province in October 2000; Upper Strickland River in April 2001; and the Balopa Islands in Manus Province in December 2002. The aim of the study was to determine the prevalence of high blood pressure and identify possible risk factors for hypertension in the 'healthy' population in Port Moresby and the three rural communities. There were 1491 subjects surveyed, 704 males and 787 females. Their ages ranged from 20 to 84 years. Just over 6% of subjects were aged 65 years and above. There were 205 (14%) smokers and 340 (23%) betelnut chewers. The Central (rural) subjects were generally younger with the lowest mean systolic and diastolic blood pressures and lowest body mass index (BMI) in both males and females (no overweight or obesity). In Central and Strickland the mean systolic (SBP) and diastolic (DBP) blood pressures were lower and remained the same in all age groups, then in females decreased with age after 55 years. The Manus (rural) subjects were older with higher mean systolic and diastolic blood pressures and higher mean BMI, surprisingly similar to the urban population of Port Moresby. The mean systolic blood pressures in Port Moresby and Manus increased with age in both sexes, while the mean diastolic pressure remained the same in all age groups in females and decreased after the age of 50 years. The prevalence of systolic hypertension among men and women was higher in Manus than in urban Port Moresby and, among the female subjects, Manus had the highest at 31%, while Central recorded the lowest for both males and females. The mean systolic blood pressures of betelnut chewers in Port Moresby, Manus and Central were lower (by 1-9 mmHg) but higher--in males only--in Strickland. The mean diastolic blood pressures of betelnut chewers were lower in all study sites. Both high BMI (overweight and obesity) and older age were significantly associated with high systolic blood pressure but betelnut chewing was significantly associated with lower mean SBP (p < 0.001), a protective effect against systolic hypertension.