Seasonal variation of blood pressure in normotensive females aged 18 to 40 years in an urban slum of Delhi, India.

Season is one of the factors affecting blood pressure. The objectives of this study are to quantify the magnitude of seasonal changes in blood pressure among normotensive women aged 18 to 40 years and to find out the association of blood pressure variation between winter and summer with body mass index, temperature, humidity, day length, and salt intake. The study was carried out on 132 women, included 4 home visits during the seasons of spring, summer, autumn, and winter. Mean increase in systolic blood pressure (SBP)/diastolic blood pressure (DBP) in winter was 11.07/6.79 mm Hg during summer (P < .001). No significant relationship in blood pressure variation with change in environmental variables was observed. Mean increase in SBP/DBP in winter was more among underweight than individuals who were normal/overweight/obese (P < .05). There was significant increase in SBP/DBP during winter compared with summer. This seasonal factor should be considered while evaluating individual blood pressure and comparing community studies.