Solar, geomagnetic activity may affect blood pressure in older men

Increased solar activity and related geomagnetic disturbances are associated with blood pressure (BP) elevations among elderly men, a study has found.

The study included 675 elderly men (mean age 72.8 years, body mass index 28.1 kg/m²) from the Normative Aging Study, with a total of 1,949 BP measurements taken over a period of 17 years. Nearly everyone (98.1 percent) in the cohort was White. Mean systolic and diastolic BP at baseline were 131.0 and 75.9 mm Hg, respectively.

Researchers evaluated the average 1‐day (ie, day of BP measurement) to 28‐day interplanetary magnetic field intensity, sunspot number, and a dichotomized measure of global geomagnetic activity (Kp index) in 4‐day increments.

BP showed a positive association with interplanetary magnetic field, sunspot number, and Kp index averaged over 16 through 28 days before BP measurement. An interquartile-range increase of 16 days in the interplanetary magnetic field and sunspot number and a higher Kp index correlated with a rise in systolic BP of 2.1 (95 percent confidence interval [CI], 0.7‒3.6), 2.7 (95 percent CI, 1.5‒4.0), and 0.4 (95 percent CI, −1.2 to 2.1) mm Hg, respectively, as well as an increase in diastolic BP of 2.5 (95 percent CI, 1.7‒3.2), 2.8 (95 percent CI, 2.1‒3.4), and 1.7 (95 percent CI, 0.8‒2.5) mm Hg, respectively.

The associations persisted despite adjustment for ambient air pollutants and ambient particle radioactivity.