114-117Results of an investigation on the correlation of daily hospital admissions of heart cases and the daily K- sums of geomagnetic activity in Hyderabad for the period 1967-72, are presented and discussed. The correlation coefficient works out to be + 0·761 ± 0·015, which is statistically significant at 95% confidence level. It is found that coronary thrombosis (heart attack) cases generally occur in rapid fluctuations and pulsations during geomagnetic disturbances caused by enhanced solar activity. The pulse rate and blood pressure for coronary cases appear to be directly related to the corresponding 3-hr range geomagnetic activity index K. It is concluded that all individuals are not equally influenced by geomagnetic disturbances. People with imperfect nervous and cardio-vascular systems (which are now recognized to be electrical in character) appear to react adversely to such disturbances under a trigger action, while those in excellent health remain unaffected
