Continuity of primary care and emergency department utilization among elderly people.

BACKGROUND: People aged 65 years or more represent a growing group of emergency department users. We investigated whether characteristics of primary care (accessibility and continuity) are associated with emergency department use by elderly people in both urban and rural areas.
METHODS: We conducted a cross-sectional study using information for a random sample of 95,173 people aged 65 years or more drawn from provincial administrative databases in Quebec for 2000 and 2001. We obtained data on the patients' age, sex, comorbidity, rate of emergency department use (number of days on which a visit was made to an emergency department per 1000 days at risk [i.e., alive and not in hospital] during the 2-year study period), use of hospital and ambulatory physician services, residence (urban v. rural), socioeconomic status, access (physician: population ratio, presence of primary physician) and continuity of primary care.
RESULTS: After adjusting for age, sex and comorbidity, we found that an increased rate of emergency department use was associated with lack of a primary physician (adjusted rate ratio [RR] 1.45, 95% confidence interval [CI] 1.41-1.49) and low or medium (v. high) levels of continuity of care with a primary physician (adjusted RR 1.46, 95% CI 1.44-1.48, and 1.27, 95% CI 1.25-1.29, respectively). Other significant predictors of increased use of emergency department services were residence in a rural area, low socioeconomic status and residence in a region with a higher physician:population ratio. Among the patients who had a primary physician, continuity of care had a stronger protective effect in urban than in rural areas.
INTERPRETATION: Having a primary physician and greater continuity of care with this physician are factors associated with decreased emergency department use by elderly people, particularly those living in urban areas.