CHANGES IN HUMAN BLOOD-PRESSURE WITH SEASON, AGE AND SOLAR-CYCLES - A26-YEAR RECORD

The record was studied of a 71-year-old, diurnally active (0700-2200 h ours) male psychiatrist (G.N.) who self-measured systolic and diastoli c blood pressure (BPS, and BPD) mostly but not exclusively on Sunday m ornings, from 1969 to 1994. A large about-yearly change was revealed w hich increased with age and was accompanied by a decreasing trend in t he yearly rhythm-adjusted mean (MESOR; P<0.01). According to conventio nal criteria that specify only upper limits of acceptability, G.N. was hypertensive in summer and normotensive in other seasons. Since chang es in both MESOR and circannual amplitude occurred, a systematic surve illance of BP is the chronobiological recommendation.