Clinical trial NCT00100061: Effects of Cranberry-Containing Products in Women With Recurrent Urinary Tract Infections (UTIs)
Official title: Dose Response to Cranberry of Women With Recurrent UTIs
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: PHASE2
Conditions: Urinary Tract Infection
Keywords: Cranberry
Vaccinium macrocarpon
Lead sponsor: National Center for Complementary and Integrative Health (NCCIH)
Sponsor class: NIH
Collaborators: name: Office of Dietary Supplements (ODS)
First posted: 2004-12-23
Enrollment: 350
Sex: FEMALE
Minimum age (years): 19
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: The purpose of this study is to determine the role of cranberry-containing products in preventing urinary tract infections (UTIs).

Detailed description: Although cranberry-containing products are commonly taken to prevent UTIs and other urinary symptoms, an optimally effective dose has not been established, and the chemicals responsible for the UTI-preventing properties in cranberry-containing products have yet to be determined. This study will determine the minimum dose of cranberry-containing product necessary to prevent UTIs, the effectiveness of cranberry-containing products in fighting different strains of E. coli, and the long-term effects of cranberry-containing product consumption. This study will also determine whether plant pigments called proanthocyanidins influence the UTI-preventing properties of cranberry-containing products.

This study will last 2 years. Participants will be randomly assigned to receive varying doses of either cranberry-containing products or placebo for 1 year. Some participants will receive cranberry or placebo supplement tablets; others will receive cranberry juice or a placebo beverage. Clinic visits will occur every 2 months; urine collection will occur at each visit. Some participants will be asked to collect 24-hour urine samples every 8 weeks and provide urine samples on Days 1, 3, 5 and 7.

Laboratory tests will be used to assess participants during the study. A 3-day course of antibiotics will be provided to participants developing a UTI during the course of the study. Telephone interview follow-up at 6 and 12 months after the study will determine whether cranberry-containing product use has continued and whether UTIs have recurred.

Eligibility criteria: Inclusion Criteria:

* At least two UTIs in the year prior to study entry
* Willing to use acceptable methods of contraception
* Willing to refrain from consuming other forms of cranberry supplementation

Exclusion Criteria:

* Current UTI
* Allergy to cranberry-containing products
* Active urinary stone disease
* Insulin-dependent diabetes
* Immunosuppressive disease
* Current corticosteroid use
* Intermittent or indwelling catheterization
* Pregnancy

Primary outcomes:
measure: Minimum dose of cranberry-containing product necessary to achieve a 30% prophylaxis of UTIs in women with recurrent UTIs
timeFrame: end of study
measure: Whether the degree of UTI prophylaxis is related to the dose of cranberry-containing product (dose response curve)
timeFrame: end of study
measure: Whether proanthocyanidin concentration in the urine correlates with UTI prophylaxis
timeFrame: end of study
Secondary outcomes:
Other outcomes:
Locations:
city: Vancouver
country: Canada
facility: Bladder Care Centre, University of British Columbia
state: British Columbia
Study officials:
affiliation: Bladder Care Centre, University of British Columbia
name: Lynn Stothers, MD
role: PRINCIPAL_INVESTIGATOR
References: