[Association of air pollution with unscheduled outpatient visits in Beijing Longfu Hospital, 1991].

Outpatient visits to Beijing Longfu Hospital, a community-based hospital, were analyzed to assess the association of air pollution with daily outpatient visits in 1991. Measurements of total suspended particulate (TSP) were available for 224 days (mean was 359 micrograms/m3) and sulfur dioxide (SO2) for 221 days (mean was 124 micrograms/m3). The effects of TSP and SO2 were assessed by linear regressions adjusting for temperature, humidity, seasons and the workdays as covariables with a Markov correction for auto-correlation in time series data. There was a significant exposure-response relationship between TSP level and non-surgery outpatient visits but not for surgery visits. SO2 was only significantly associated with pediatric visits.