title: Blood-pressure and its correlates in urban and tribal Africa.
abstract: Blood-pressure and associated factors were compared in tribal and urban Xhosa people of Southern Africa. In the urban group blood-pressures were high and rose significantly with age whereas in the tribal group they were low and rose little with age. Indices of obesity including weight, skin-fold thickness, and ponderal index were significantly greater in urban dwellers and correlated strongly with arterial pressure. Dietary sodium and urine-sodium/creatinine ratio were significantly higher in the urban people, but there was no within-population relationship between either dietary sodium or urine-sodium/creatinine ratio and blood-pressure. Plasma-noradrenaline, an index of sympathetic activity, was similar in both populations, as was plasma-renin activity. Low plasma-renin was common and may be genetically determined. Diet and obesity may contribute to the rise in arterial pressure that is a consequence of urbanisation.
mesh_terms: D000293:Adolescent; D000328:Adult; D000353:Africa, Southern; D000367:Age Factors; D000368:Aged; D044383:Black People; D001794:Blood Pressure; D002648:Child; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000453:epidemiology* / Q000652:urine; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology; D012083:Renin / Q000097:blood; D012306:Risk; D012424:Rural Population; D012964:Sodium / Q000652:urine; D014505:Urban Population; D044465:White People
chemical_list: D012964:Sodium; D012083:Renin