Risk factors for community-acquired pneumonia diagnosed upon hospital admission

A case-control study of risk factors for community-acquired pneumonia in ad ults admitted to hospital is reported. Cases were surviving patients (n = 1 78) admitted to 14 hospitals in England. Controls were individuals (n = 385 ) randomly selected from the electoral registers of the areas served by the hospitals. The two groups were compared with regard to risk factors for pn eumonia using a standardized postal questionnaire. Independent risk factors associated with cases in log-linear regression analysis were age, heart di sease (as indicated by congestive heart Failure and/or digitalis treatment) , lifetime smoking history, chronic airway disease (chronic bronchitis and/ or asthma), occupational dust exposure, pneumonia as a child, single marita l status and unemployment. Corticosteroid and bronchodilator therapy were a lso independent risk factors in the log-linear regression analysis, but may reflect the severity of underlying lung disease for which these drugs were prescribed. These data suggest that cigarette smoking is the major avoidab le risk factor for acute pneumonia in adults.