Elderly nursing home patients with congestive heart failure after myocardial infarction living in new york city have a higher prevalence of mortality in cold weather and warm weather months.

Abstract

Some studies have found an increase in cardiac events in the winter months. Other studies, from cities in the southern half of the United States, have shown an increase in cardiac events during the summer months. We investigated in a prospective study of 517 patients, mean age 81 +/- 8 years, with congestive heart failure (CHF) after prior myocardial infarction who died in a nursing home in New York City with 24-hour on-site physician coverage, whether there was a seasonal variation in mortality from CHF. The exact binomial test was used to see if the number of deaths from CHF in the cold weather and warm weather months was significantly different from those in the spring and fall. Of 517 patients who died, 321 deaths (62%) occurred during the months of December, January, February, March, July, and August, and 196 deaths (38%) occurred during the other 6 months (p <.0001). The number of deaths in patients with CHF after prior myocardial infarction in cold weather and warm weather months is significantly higher than those in spring and fall months (p <.0001).