Does increased urination frequency protect against bladder cancer?

Division of Cancer Epidemiology and Genetics, National Cancer Institute, Department of Health and Human Services, Bethesda, MD 20892, USA.
International Journal of Cancer (Impact Factor: 5.09). 10/2008; 123(7):1644-8. DOI: 10.1002/ijc.23572
Source: PubMed


Experimental studies suggest that increased urination frequency may reduce bladder cancer risk if carcinogens are present in the urine. Only 2 small studies of the effect of increased urination frequency on bladder cancer risk in humans have been conducted with conflicting results. Our purpose was to evaluate the effect of urination frequency on risk of bladder cancer in a large, multicenter case-control study. We analyzed data based on interviews conducted with 884 patients with newly diagnosed, bladder cancer and 996 controls from 1998 to 2001 in Spain. We observed a consistent, inverse trend in risk with increasing nighttime voiding frequency in both men (p = 0.0003) and women (p = 0.07); voiding at least 2 times per night was associated with a significant, 40-50% risk reduction. The protective effect of nocturia was apparent among study participants with low, moderate and high water consumption. The risk associated with cigarette smoking was reduced by nocturia. Compared with nonsmokers who did not urinate at night, current smokers who did not urinate at night had an OR of 7.0 (95% CI = 4.7-10.2), whereas those who voided at least twice per night had an OR of 3.3 (95% CI = 1.9-5.8) (p value for trend = 0.0005). Our findings suggest a strong protective effect of nocturia on bladder cancer risk, providing evidence in humans that bladder cancer risk is related to the contact time of the urothelium with carcinogens in urine. Increased urination frequency, coupled with possible dilution of the urine from increased water intake, may diminish the effect of urinary carcinogens on bladder cancer risk.

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Available from: Kenneth Cantor, Dec 09, 2014
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    • "Several potential mechanisms have been proposed to explain the associations of fluid intake and bladder cancer risk. A higher level of fluid consumption could reduce the contact time between urinary carcinogens and the bladder urothelium through increasing urination frequency, which could reduce the risk of bladder cancer [23,38,39]. We should note that the amount of total fluid ingested and urination frequency may not present a positive correlation among older men because of benign prostatic hyperplasia, which can cause frequent micturition [35]. "
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    ABSTRACT: Objectives Epidemiological findings regarding the association between total fluid intake and bladder cancer risk have yielded varying results. Our objective is to examine the possible associations between total fluid intake and bladder cancer risk. Methods Databases searched include the EMBASE and PUBMED, from inception to February 2014, with no limits on study language. We also reviewed the reference lists of identified studies. Stratified analyses were performed. A random-effect model was used to summarize the estimates of odds ratio (OR) with 95% confidence intervals (CI). Results Overall,17 case-control and four cohort studies were included. The overall OR of bladder cancer for the highest versus the lowest fluid intake was 1.06 (95% CI: 0.88-1.27). In the subgroup analyses, the overall ORs for coffee, green, and black tea intake were 1.17 (95% CI: 1.03-1.33), 0.76 (95% CI: 0.66-0.95), and 0.80 (95% CI: 0.65-0.97), respectively. A significantly decreased risk was observed in Asian people (OR 0.27; 95% CI: 0.10-0.72). Among smokers, a suggestive inverse association was observed between total fluid intake and overall bladder cancer risk (OR 0.80; 95% CI: 0.62-1.02). Conclusions Although this meta-analysis suggested that greater consumption of fluid may have a protective effect on bladder cancer in Asian people, there was no convincing evidence on this association because of the limitations of the individual trials.
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    ABSTRACT: We evaluated the long-term outcome of simultaneous transurethral bladder tumor and prostate resection in patients with nonmuscle invasive bladder tumor and bladder outlet obstruction. Between April 1997 and April 2006, 213 patients with nonmuscle invasive bladder tumor who had a minimum followup of 24 months were included in the study, including group 1-107 with transurethral resection of bladder tumor only and group 2-106 with transurethral bladder tumor and prostate resection. Simultaneous transurethral bladder tumor and prostate resection was performed at surgeon discretion. The records were retrospectively analyzed for clinicopathological parameters, recurrence and progression rates, time to recurrence and postoperative uroflowmetry results in the 2 groups. There were no significant differences in clinicopathological parameters between the 2 groups. At a mean followup of 54.3 and 50.1 months in groups 1 and 2, respectively, group 2 patients with a tumor less than 3 cm or a single tumor had a significantly lower recurrence rate than group 1 patients. None of the 31 patients with recurrence in group 2 had recurrence in the bladder neck or prostatic urethra where transurethral prostate resection had been done. There was no significant difference in the progression rate between the 2 groups. The 60-month recurrence-free probability in groups 1 and 2 was 43.4% and 52.0%, respectively. Three months after surgery the postvoid residual urine volume had significantly decreased in group 2. Simultaneous transurethral bladder tumor and prostate resection may help decrease bladder cancer recurrence and delay time to recurrence without the risk of cancer implantation when transurethral prostate resection is done, especially in patients with a papillary, solitary-appearing bladder lesion less than 3 cm.
    No preview · Article · Mar 2009 · The Journal of urology
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    ABSTRACT: We evaluated whether screening high risk asymptomatic individuals with a bladder tumor marker can lead to earlier detection and resultant down staging of bladder cancer. Subjects at high risk for bladder cancer based on age and smoking or occupational status were solicited from 2 well patient clinics from March 2006 to November 2007. NMP22 BladderChek testing was performed on voided urine samples. Those with positive test results underwent office cystoscopy and cytology testing. Participants were contacted for followup at 12 months after study enrollment to evaluate for unrecognized bladder cancer. A total of 1,175 men and 327 women underwent BladderChek testing. Mean participant age was 62.5 years (range 46 to 92). Based on 10-year or greater smoking history 1,298 participants were enrolled while 513 were enrolled based on a greater than 15-year high risk occupation for bladder cancer. Positive BladderChek testing was observed in 85 (5.7%) participants and 69 agreed to undergo cystoscopy. Three types of lesions were diagnosed including multifocal, high grade Ta (1); Ta, low grade tumor (1) and marked atypia (1). Followup was available in 1,309 subjects. Mean followup was 12 months (range 0.9 to 25.5) and 2 of 1,309 participants had low grade noninvasive bladder cancer. Evaluation of patient records revealed that 73.4% of participants had urinalysis within 3 years before screening. NMP22 BladderChek for screening an asymptomatic, high risk population can detect noninvasive cancers but the low prevalence of bladder cancer in this population did not permit assessment of intervention efficacy. Frequent use of urinalyses in high risk persons may attenuate future efforts to study the effects of bladder cancer screening tests.
    Full-text · Article · Jun 2009 · The Journal of urology
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