Differentials in resting heart rates and blood pressures between a high and low altitude sample of southern Peruvian Quechua

The Andean Quechua demonstrate bradycardia and lowered systemic pres sures compared to the physiological norms of many low altitude populations. In order to investigate the effect of altitude on heart rate and blood pressure of the Quechua a survey was carried out on young males in two genetically related Quechua populations living at high and low altitudes in southern Peru. Comparisons were made between these two groups and with existing data on selected non-Quechua populations. Signifi cant differences were found to exist between the high and low altitude Quechua, the latter showing greater bradycardia and higher pulse pressures. However, both Quechua groups were more similar to each other than to the non-Quechua populations. The implications of this are discussed in the context of the effects of genetics and environ ment on the development of these parameters in the Quechua.