Table 4 Clinical trials of cranberry products for UTI prevention in different populations

Randomized, double-blind, placebo-controlled trial

Cranberry juice of 300 ml/day or placebo

153 elderly women

UTI incidence 15% in cranberry group and 28.1% in placebo group (difference is non-significant)

[89]

Randomized, single-blind cross over study

15 ml juice/kg or water placebo

21 patients with neuropathic bladder

9 patients taking cranberry juice and 9 patients taking water showed lowered infection, rest 3 were indifferent.

[90]

Randomized, double-blind, crossover trial

Cranberry capsules of 400 mg

19 female having recurrent UTIs

UTI incidences were 2.4/subject/year in cranberry group and 6.0/subject/year in placebo, 47.4% of withdrawal rate.

[91]

Double-blind placebo controlled with crossover

60 ml/day of cranberry juice or placebo

15 children under intermittent catheterization

Differences between groups are nonsignificant for bacteriuria or UTI.

[92]

Randomized, double-blind, placebo-controlled

50 ml of cranberry-lingonberry juice (7.5 g), Lactobacillus GG 100 ml/day or placebo

150 young women with previous UTI

Recurrence rate of UTI reduced in cranberry group, 20% less UTI in cranberry group.

[93]

Randomized, double-blind, placebo-controlled

Cranberry juice 250 ml or its tablets

150 women with recurrent UTIs

Incidence of UTI—30% in juice, 39% in tablets group and 72% in placebo

[94]

Randomized, double-blind, placebo-controlled

Cranberry capsules of 8 g or placebo

135 patients with complicated UTI (multiple sclerosis generated neurogenic bladder)

34.6% UTI in cranberry group and 32.4% on placebo, no significant difference between the groups and also under intermittent catheterization.

[95]

Randomized, double-blind, placebo-controlled

Cranberry capsules of 1 g or placebo

74 patients with neurogenic bladder induced by spinal cord injury

Insignificant differences in bacteriuria, pyuria, or symptomatic UTIs between the groups, 35% withdrawal rate

[96]

Double-blind, placebo controlled with crossover

400 mg of cranberry tablets for 4 weeks or placebo

37 patients with neurogenic bladder due to spinal cord injury

43% of withdrawal rate and no difference were observed between the cranberry and the placebo group.

[97]

Randomized, double-blind, placebo-controlled

25% of cranberry juice (150 ml) and placebo

376 in door old patients (> 60 years)

3.7% of UTI incidences in cranberry group of 7.4% with placebo 31% withdrawal rate

[98]

Double-blind, randomized, placebo-controlled

1st group—methenamine hippurate (MH), 2nd—cranberry (800 mg), 3rd—cranberry + MH, and 4th—placebo

305 patients with spinal cord injury resulted neurogenic bladder

No differences for symptomatic UTI groups to placebo

[99]

Randomized, double-blind, placebo-controlled trial

Group A—240 mg of 27% cranberry juice 3 times/day or group B—240 mg daily once or group C—placebo

188 pregnant women of 16 weeks gestation

No significant differences in UTI occurrence between the groups. Withdrawal rate of 38.8% (A, 50.7%, B, 39.7%, C, 55.5%)

[100]

Randomized, double-blind, placebo-controlled trial

Cranberry extract tablet for 6 months

47 spinal cord injured patients

0.3 UTI per year in cranberry group vs 1.0 UTI per year in placebo.

[101]

Randomized, double-blind, placebo-controlled trial

cranberry extract (500 mg)

or trimethoprim (100 mg)

137 women with recurrent UTIs—age 45 years

25 UTIs in cranberry group and14 in trimethoprim group

[102]

Randomized controlled trial

Cranberry-lingonberry juice 50 ml/day, Lactobacillus GG 100 ml, 5 days/month or placebo

84 girls with recurrent UTIs

UTIs incidence 18.5% in 1st group, 42.3% in 2nd, and 48.1% in placebo

[103]

Randomized, double-blind, placebo-controlled trial

27% cranberry juice (8 oz.)

319 young women with UTI history

UTI recurrence rates—19.3% for cranberry group and 14.6% for placebo

[104]

Randomized, double-blind, placebo-controlled trial

Cranberry juice

263 children cranberry (n = 129), placebo (n = 134)

0.1% UTI episodes lower in cranberry gr.

[105]

Randomized, double-blind, placebo-controlled trial

200 mg of cranberry

370 prostate cancer patients

8.7% UTI in cranberry group, 24.2% in placebo (36% reduction in UTI)

[106]

Randomized, double-blind, placebo-controlled trial

Cranberry juice 4, 8 oz/daily, or placebo

176 patients (120 to cranberry juice and 56 to placebo)

0.29 UTI in cranberry juice group and 0.37 in the placebo group. P-fimbriated UPEC isolation was 43.5% (10 of 23) in cranberry juice group, 80.0% (8 of 10) in placebo group during the study period

[107]

Randomized, double-blind, placebo-controlled trial

3 capsules of PAC daily for 30 days (108 mg, 72 mg, 36 mg)

80 women

Dose-dependent reduction in bacteriuria and pyuria

[108]

Modified observational study

Sweetened dried cranberry (SDC) of one serving daily for 14 days

20 women with recurrent UTIs

Mean UTI rate per six months decreased significantly, no UTI observed in > 50% of the patients up to 6 months of SDC consumption

[109]

Randomized, double-blind, placebo-controlled multicenter trial

Capsules of cranberry and placebo were taken twice daily for 1 year

928 women of high and low risk group

Incidence of UTI reduced in cranberry than placebo group (62.8 vs 84.8 per 100 person-years in UTI high risk group). No difference observed in low UTI risk group

[110]

Randomized, double-blind, placebo-controlled trial

Two cranberry juice capsules twice daily for 6 weeks or placebo

160 women undergoing gynecological surgery involving urinary catheterization (80 + 80)

19% UTI incidence in cranberry group compared to 38% in placebo group

[111, 112]

Randomized, double-blind, placebo-controlled trial

500 mg of whole cranberry fruit powder for 6 months or placebo

Cranberry (n = 89) or a placebo group (n = 93)

UTI occurrence significantly lowered 10.8% vs 25.8% in cranberry and placebo group, respectively

[113]

Randomized, double-blind, placebo-controlled trial

240 ml of cranberry juice per day for 24 weeks or placebo

Cranberry (n = 185) or a placebo (n = 188)

UTI occurrence significantly lowered 21% vs 36% in cranberry and placebo group, respectively

[114]