Antibiotic duration for treating uncomplicated, symptomatic lower urinary tract infections in elderly women

Urinary tract infections are common in elderly patients. Authors of non systematic literature reviews often recommend longer treatment durations (7-14 days) for older patients than for younger women, but the scientific evidence for such recommendations is not clear.

To determine the optimal duration of antibiotic treatment for uncomplicated symptomatic lower urinary tract infections in elderly women.

We contacted known investigators and pharmaceutical companies marketing antibiotics used to treat urinary tract infections, screened the reference list of identified articles, reviews and books, and searched the following data bases: MEDLINE, EMBASE, CINAHL, Healthstar, Popline, Gerolit, Bioethics Line, The Cochrane Library, Dissertation Abstracts International, Index to Scientific & Technical Proceedings.

All randomized controlled trials in which different treatment durations of oral antibiotics for uncomplicated symptomatic lower urinary tract infections in elderly women were compared. We excluded patients with fever or flank pain and those with complicating factors. Trials with treatment durations longer than 14 days or designed for prevention of urinary tract infection were also excluded. No language restriction was applied.

The quality of all selected trials was assessed and data extracted by the reviewers. Main outcome measures were persistence of urinary symptoms (short-term and long-term efficacy), effect on mental and functional status and adverse drug reactions. To compare the different treatment durations, we defined the following categories of duration: single dose, short course (3-6 days) and long course (7-14 days). Relative risk (RR) and 95% confidence intervals (CI) were calculated for each trial and outcome and were then combined using a random effects model.

Thirteen trials were included in this review. Six trials compared single dose with short-term treatment (3-6 days), three studies single dose with long-term treatment (7-14 days) and four trials short-term with long term treatment. Eight trials also included younger patients, but provided a subgroup analysis for elderly women. The methodological quality of all trials was low. All trials reported results of bacteriological cure rate; less often clinical outcomes (e.g. improvement or cure of symptoms) were analyzed. Only five trials compared the same antibiotic given for a different length of time. We performed a separate analysis for these trials. The rate of persistent bacteriuria rate at short-term (two weeks post-treatment) was better in the longer treatment group (3-14 days) than in the single dose group (RR 1.84, 95% CI 1.18 to 2.86). However, the rate of persistent bacteria at long term and the clinical cure rate showed no statistically significant difference between the two groups. Patients showed a preference for single dose treatment (RR 0.73, 95% CI 0.66 to 0.88), however this was based on only one trial comparing the same antibiotic. The comparison of short (3-6 days) and longer treatments (7-14 days) did not show any significant difference, but the number of included studies and sample size were low.

This review suggests that single dose antibiotic treatment is less effective but may be better accepted by the patients than longer treatment durations (3-14 days). In addition there was no significant difference between short course (3-6 days) versus longer course (7-14 days) antibiotics. The methodological quality of the identified trials was poor and the optimal treatment duration could not be determined. We therefore need more appropriately designed randomized controlled trials testing the effect, - on clinical relevant outcomes -, of different treatment durations of a given antibiotic in a strictly defined population of elderly women.