Yes, not just respiratory illnesses and iflux of viruses, heart diseases too, can be a cause of worry during the winters and the sudden drop in temperatures.

from Times of India https://timesofindia.indiatimes.com/life-style/health-fitness/health-news/winter-heart-attacks-know-why-heart-attacks-are-more-common-during-winter-season-tips-to-reduce-your-risk/photostory/87758423.cms