Blood pressure in four remote populations in the INTERSALT Study.

Abstract

Four remote population samples (Yanomamo and Xingu Indians of Brazil and rural populations in Kenya and Papua New Guinea) had the lowest average blood pressures among all 52 populations studied in INTERSALT, an international cooperative investigation of electrolytes and blood pressure. Average systolic blood pressure was 103 versus 120 mm Hg in the remaining INTERSALT centers; diastolic blood pressure in these four population samples averaged 63 versus 74 mm Hg in the 48 other centers. There was little or no upward slope of blood pressure with age; hypertension was present in only 5% of the rural Kenyan sample and virtually absent in the other three centers. Also in marked contrast with the rest of the centers was level of daily salt intake, as estimated by 24-hour urinary sodium excretion. Median salt intake ranged from under 1 g to 3 g daily versus more than 9 g in the rest of INTERSALT populations. Average body weight was also low in these four centers, with no or low average alcohol intake, again unli...