UTI is the most common bacterial infection among the elderly, the severity of which ranges from a mild self-limiting illness to severe sepsis, with a mortality rate of 20 to 40%.
With more than half of empirical antibiotics prescribed for a suspected UTI in older adults being considered unnecessary, the researchers conducted a study to evaluate the association between antibiotic treatment for UTI and severe adverse outcomes in elderly patients in primary care.
Further informationView full studyView antibiotic entries in MIMSView MIMS table: Antibiotic Treatments in Adults,
Population-based cohort study
The researchers used Clinical Practice Research Datalink primary care records linked to hospital episode statistics and death records in England to identify 157,264 adults aged 65 years or older presenting to a GP with at least one diagnosis of suspected or confirmed lower UTI from November 2007 to May 2015.
A total of 312,896 UTI episodes were identified, for which antibiotic prescribing was lacking or was deferred (within 7 days of initial consultation) in 7.2% and 6.2% of cases, respectively.
Rates of sepsis
Overall, 1,539 episodes of sepsis occurred within 60 days after an initial UTI, the rate of which was significantly higher among patients not prescribed an antibiotic or prescribed deferred antibiotics compared with those prescribed immediate antibiotics (2.9% and 2.2% vs 0.2%, respectively; p<0.001).
After adjustment for co-variates, patients were significantly more likely to develop sepsis in the no antibiotics group (8.08, 7.12-9.16) and deferred antibiotics group (adjusted odds ratio 7.12, 95% CI 6.22-8.14) than in the immediate antibiotics group. The number needed to harm (NNH) for occurrence of sepsis was lower (greater risk) for the no antibiotics group (NNH=37) than for the deferred antibiotics group (NNH=51) compared with the immediate antibiotics group.
Hospital admissions and mortality
The data also showed significantly greater rates of hospital admissions associated with no antibiotic and deferred antibiotic use compared with immediate antibiotic use (27.0% and 26.8% vs 14.8%, p=0.001). In addition, compared with immediate antibiotics the risk of all-cause mortality at any time during the 60 days of follow-up was 2.18 times higher with no antibiotics and 1.16 times higher with deferred antibiotics. Men older than 85 years were particularly at risk for both sepsis and 60-day all-cause mortality.
Early initiation advocated in elderly
The researchers conclude that their findings suggest the early initiation of antibiotics for UTI in older high-risk adult populations (especially men over 85 years) should be recommended to prevent serious complications.