Researchers have observed a potential link between winter months and blood pressure control. Examining records from 60,676 patients with hypertension, researchers found that systolic blood pressure increased by up to 1.7mmHg in December through February, compared to July to September. Additionally, blood pressure control rates fell by up to five percent during the winter. This study suggests that patients with hypertension might require more monitoring or improvements in physical activity and healthy diets during the winter. 

Source: ScienceDaily. Cold weather may pose challenges to treating high blood pressure. 7 Sep 2023. https://www.sciencedaily.com/releases/2023/09/230907130418.htm. Accessed 22 Sep 2023.