Toegenomen sterfte van verpleeghuispatienten bij extreme buitentemperatuur: toename groter bij hitte dan bij koude

Objective. To investigate the effect of ambient air temperatures on mortality among nursing home patients, and to identify subgroups of patients particulary vulnerable to effects of heat and cold. Design. Analysis of mortality data from SIG Nursing Home Information System (SIVIS) recorded in 1993 and 1994. Setting. All 289 Dutch nursing homes (89.5%) that register patient data at SIO Zorg informatie, Utrecht. Methods. For each week numbers of patients present and deceased were obtained subdivided by sex, age, level of dependence, and diagnoses. Weekly averages for maximum daily outdoor air temperatures were obtained from the Dutch national metereologic institute (KNMI), De Bilt. Results. The lowest mortality rates were observed in weeks with average outdoor temperatures between 15 and 19,9°C. In the coldest weeks (0-4,9°C) the mortality rate rose by 22%. As outdoor temperatures rose above 25°C, the mortality rate rose by 50%. The highest relative risks of dying during the cold winter spells were observed among patients of advanced age (> 95), who were independent in activities of daily living, and who had Parkinson's disease, cardiovasculair disease, COPD, disease of locomotor system and connective tissue or a hip fracture. The highest relative risks of dying during the hot summer spells were observed among the female population, patients with a high level of dependence in activities of daily living, and patients with dementia, amnestic syndrome or Parkinson's disease. Conclusions. Nursing home patients were extremely vulnerable when outdoor temperatures rose above 25°C. High temperatures had much more effect on mortality rates than low temperatures.