DOES ASYMPTOMATIC BACTERIURIA PREDICT MORTALITY AND DOES ANTIMICROBIAL TREATMENT REDUCE MORTALITY IN ELDERLY AMBULATORY WOMEN

Objective: To determine whether asymptomatic bacteriuria in elderly am bulatory women is a marker of increased mortality and, if so, whether it is because of an association with other determinants of mortality o r because asymptomatic bacteriuria is itself an independent cause, the removal of which might improve longevity. Design: A cohort study and a controlled clinical trial of the effect of antimicrobial treatment. Setting: A geriatric center and 21 continuing care retirement communit ies. Participants: Women without urinary tract catheters. Measurements : Urine cultures every 6 months (the same organism at 10(5) colony-for ming units or more per mL on two midstream urine specimens defined asy mptomatic bacteriuria), comorbidity, and mortality. Results: In the ob servational study, infected residents (n = 318) were older, and sicker , and had higher mortality (18.7 per 100 000 resident-days) than uninf ected residents (n = 1173; 10.1 per 100 000 resident-days). However, i n a multivariate Cox analysis, infection was not related to mortality (relative risk, 1.1; P > 0.2), whereas age at entry and self-rated hea lth (score 1 [excellent] to 4 [bad or poor]) were strong predictors. I n the clinical trial, mortality in 166 treated residents (13.8 per 100 000 resident-days) was comparable to that of 192 untreated residents (15.1 per 100 000 resident-days); the relative rate was 0.92 (95% CI, 0.57 to 1.47). The cure rates among treated and untreated residents we re 82.9% and 15.6%, respectively. Conclusion: Urinary tract infection was not an independent risk factor for mortality, and its treatment di d not lower the mortality rate. Screening and treatment of asymptomati c bacteriuria in ambulatory elderly women to decrease mortality do not appear warranted.