About half-weekly (circasemiseptan) pattern of blood pressure and heart rate in men and women of India

For a reliable diagnosis of hypertension, around-the-clock monitoring for 7 days or longer has been advocated. As part of a larger study in India, 32 subjects had their blood pressure and heart rate measured manually every 3 h for 7 days. As expected, spectral peaks corresponded to circadian variation. The about half-weekly component was statistically significant. Separate analyses of the data collected during consecutive days indicated that large day-to-day changes may, in part, have been accounted for by adaptation to the measurements. The results corroborate the view that, if reliable values are to be obtained, serial measurements for at least 7 days are needed.