Blood pressure and lifestyle change among the Manus of Papua New Guinea: A migrant study

Abstract

The health consequences of migration and rapid modernization are examined in the Manus people living in Pere village in Manus Province and in migrants living in both the local provincial towns and larger cities of Papua New Guinea. For the Manus, like so many other Pacific Island peoples and other modernizing populations around the world, lifestyle change has resulted in increased blood pressure and rates of hypertension in both adults and youth, placing them at greater risk for cardiovascular pathology. Higher blood pressure is accompanied by greater body weight, mass and fatness and also by differences in body fat distribution among the predominantly young adult migrants compared to their village relatives. Higher blood pressure among town youth is attributed to their greater body size and growth status. Changes in diet, educational and occupational status, marriage patterns, physical activity levels, health care, and fertility and mortality patterns have also occurred with modernization and directly or indirectly affect blood pressure variation among migrants. In addition to greater fat levels, migrants also show differences from villagers in the relative distribution of subcutaneous fat on the body. A greater centripetal distribution of fat, particularly greater subscapular or upper back fat, is significantly associated with both blood pressure level and the response of blood pressure to postural change among both village and town adults. Manus migrant men have a high incidence of borderline hypertension compared to young adult men living in the United States. Adiposity and occupational status significantly and independently predict blood pressure levels among these men suggesting that, in addition to physical factors, psychosocial stress plays a role in the etiology of blood pressure elevation in this population. Because the Manus of Pere village have been studied extensively over the past six decades by both cultural and biological anthropologists, it has been possible to carefully assess the impact of social and cultural change upon human biology and health in this population