Do space weather conditions affect headache occurrence? A longitudinal analysis of daily headache reports from Serbia

The potential influence of solar activity and space weather on human health has been investigated for more than a century; however, research regarding headache occurrence and solar activity are underrepresented in the literature. The present study investigated whether daily solar and geomagnetic conditions were associated with headache occurrence using prospectively collected headache diary data. Daily headache records were obtained from 26 participants over a 120-day period (1 January- 30 April 2025). Solar activity was characterized using the daily sunspot number, daily number of C-class and M-class solar flares, the total number of solar flares of at least C class, and the Kp index. Generalized linear mixed models were applied to evaluate associations between headache occurrence and solar and space weather parameters. Continuous and threshold-based analyses (85th percentile), together with one-day lagged variables, were performed. No statistically significant associations were identified between headache occurrence and any of the analyzed solar activity or space weather parameters, irrespective of whether continuous, lagged, or threshold-based models were considered. Female participants exhibited significantly higher odds of reporting headaches than males, whereas age was not significantly associated with headache occurrence. These findings did not provide evidence of a short-term association between the analyzed solar activity or geomagnetic parameters and daily headache occurrence in the studied population. Future studies involving larger and more diverse populations, longer observation periods spanning multiple phases of the solar cycle, and additional space weather parameters are warranted to further evaluate potential relationships between solar activity, space weather, and human health.