Chronic health conditions, such as COPD and congestive heart failure, can be exacerbated over the holiday season.

A 2010 Hamilton, Ontario study found that this time of year is a genuine risk factor for people with COPD, who end up in hospital more often during the holidays. The researchers, led by Neil Johnston, an epidemiologist with the Firestone Institute for Respiratory Health, monitored 71 people with COPD from December to May. They found 47 exacerbations – about 6.7/week – occurred during the holiday period, while 63 exacerbations – about 4.3/week – occurred during the remainder of winter.