Cranberry juice concentrate does not significantly decrease the incidence of acquired bacteriuria in female hip fracture patients receiving urine catheter: a double-blind randomized trial

Abstract

Background: Urinary tract infection (UTI) is a common complication among patients with hip fractures. Receiving an indwelling urinary catheter is a risk factor for developing UTIs. Treatment of symptomatic UTIs with antibiotics is expensive and can result in the development of antimicrobial resistance. Cranberries are thought to prevent UTI. There is no previous research on this potential effect in patients with hip fracture who receive urinary catheters.

Aim: The aim of this study is to investigate whether intake of cranberry juice concentrate pre-operatively decreases the incidence of postoperative UTIs in hip fracture patients that received a urinary catheter.

Design: This study employed a randomized, placebo-controlled double-blind trial.

Method: Female patients, aged 60 years and older, with hip fracture (n=227) were randomized to receive cranberry or placebo capsules daily, from admission, until 5 days postoperatively. Urine cultures were obtained at admission, 5 and 14 days postoperatively. In addition, Euro Qual five Dimensions assessments were performed and patients were screened for UTI symptoms.

Result: In the intention-to-treat analysis, there was no difference between the groups in the proportion of patients with hospital-acquired postoperative positive urine cultures at any time point. When limiting the analysis to patients that ingested at least 80% of the prescribed capsules, 13 of 33 (39%) in the placebo group and 13 of 47 (28%) in the cranberry group (P=0.270) had a positive urine culture at 5 days postoperatively. However, this difference was not statistically significant (P=0.270).

Conclusion: Cranberry concentrate does not seem to effectively prevent UTIs in female patients with hip fracture and indwelling urinary catheter.

Keywords: elderly; hospital; preventive; randomized controlled trial; urinary tract infection; urine culture.

Figure 1

Proportion of patients with positive urine cultures. Notes: (A) Percentage of all randomized patients with positive urine culture at admittance, five and 14 days postoperative. (B) Percentage of hospital-acquired positive urine cultures in the ITT population at 5 and 14 days postoperatively and at either 5 or 14 days postoperatively. The blue bars represent the placebo-treated patients and the red bars the cranberry-treated patients. The total number of patients in each group is shown above each bar. No significant difference between the groups was found using chi-square test. Abbreviation: ITT, intention-to-treat.

Figure 2

Analysis of patients that had taken >80% of administered capsules. Notes: Percentage of hospital-acquired positive urine cultures at 5 and 14 days postoperatively and at either 5 or 14 days postoperatively. (A) shows the analysis in the total PP population and (B) shows the result when excluding patients who had taken antibiotics other than the prophylaxis during the study. The blue bars represent the placebo-treated patients and the red bars the cranberry-treated patients. The total number of patients in each group is shown above each bar. No significant difference between the groups was found using chi-square test. Abbreviation: PP, per-protocol.