Ambulatory blood pressure in 570 Danes aged 19-21 years: the Odense Schoolchild Study

Ambulatory blood pressure (ABP) measurements were performed in a Danish population of 295 males and 275 females aged 19-21 years. Individualised day and night periods were defined from the subjects own recording of bedtime and rising on the day of their ABP measurements. During these individualised periods the ABP values for daytime, night-time and for the whole 24-h period were measured. The mean +/- s.d. values for systolic/diastolic ABP for the whole population were (124+/-11)/(70+/-7) mm Hg in the daytime, (106+/-12)/(60+/-9) mm Hg in the night-time, and (120+/-11)/(68+/-7) mm Hg in the whole 24-h period. Males had a mean systolic ABP of 9 mm Hg and mean diastolic ABP of 5 mm Hg higher than females. In males mean +/- s.d. systolic/diastolic ABP values in the daytime were (129+/-10)/(73+/-7) mm Hg, in the night-time (111+/-12)/(63+/-8) mm Hg, and in the whole 24-h period (125+/-10)/(71+/-7) mm Hg. The corresponding values in females were (119+/-10)/(68+/-6) mm Hg, (103+/-11)/(57+/-8) mmHg, and (115+/-10)/(66+/-6) mm Hg, respectively. In conclusion this study provides sex-specific normal values for ABP in a 19 to 21-year-old age group based on individualised daytime and night-time periods.