Fluid intake and risk of bladder cancer in the Nurses' Health Studies

Low daily water intake profile-is it a contributor to disease?

Few previous review articles have focused on the associations between inadequate daily water intake (LOW) or urinary biomarkers of dehydration (UD; low urine volume or high urine osmolality) and multiple diseases. Accordingly, we conducted manual online searches (47 key words) of the PubMed, Embase, and Google Scholar databases with these inclusion criteria: English language, full-text, peer reviewed, no restriction on research design, and three publications minimum. Initially, 3,903 articles were identified based on their titles and abstracts. Evaluations of full length .pdf versions identified 96 studies that were acceptable for inclusion. We concluded that the evidence is insufficient or conflicting for seven disorders or diseases (i.e. suggesting the need for additional clarifying research) and it is lacking for all-cause mortality. Differential characterizations among women and men have been reported in the results of nine studies involving five diseases. Finally, the evidence for associations of LOW or UD is strong for both kidney stones and type 2 diabetes with hyperglycemia. This suggests that great public health value (i.e. reduced disease risk) may result from increased daily water intake-a simple and cost-effective dietary modification.

Risk Factors Involved in the High Incidence of Bladder Cancer in an Industrialized Area in North-Eastern Spain: A Case-Control Study

Bladder cancer (BC) is the most common of the malignancies affecting the urinary tract. Smoking and exposure to occupational and environmental carcinogens are responsible for most cases. Vallès Occidental is a highly industrialized area in north-eastern Spain with one of the highest incidences of BC in men. We carried out a case-control study in order to identify the specific risk factors involved in this area. Three hundred and six participants were included (153 cases BC and 153 controls matched for age and sex): in each group, 89.5% (n = 137) were male and the mean age was 71 years (range 30-91; SD = 10.6). There were no differences between groups in family history, body mass index, or dietary habits. Independent risk factors for CV were smoking (OR 2.08; 95% CI 1.30-3.32; p = 0.002), the use of analgesics in nonsmokers (OR 10.00; 95% CI 1.28-78.12; p = 0.028), and profession (OR: 8.63; 95% CI 1.04-71.94; p = 0.046). The consumption of black and blond tobacco, the use of analgesics in nonsmokers, and occupational exposures are risk factors for the development of BC in this area, despite the reduction in smoking in the population and the extensive measures taken in the last few decades in major industries to prevent exposure to occupational carcinogens.

Genetically supported causality between benign prostate hyperplasia and urinary bladder neoplasms: A mendelian randomization study

Background: Observational studies have suggested a possible association between benign prostate hyperplasia (BPH) and bladder cancer (BLCA). However, these studies are prone to errors and limitations or confounding factors, making them unsuitable for assessing the causal relationship between BPH and BLCA. Objective: Two-sample Mendelian randomization (MR) was performed to determine a possible association between genetically predicted BPH and the risk of BLCA. Methods: A two-sample MR analysis was performed utilizing the Integrative Epidemiology Unit genome-wide association (GWAS) database of the Medical Research Council, United Kingdom A series of control steps, including five primary methods, were performed to identify the most suitable instrumental variables (IVs) for MR analysis. Sensitivity analysis was conducted to avoid statistical errors, including heterogeneity and pleiotropic bias. Results: Genetic variants associated with BPH (P < 5 × 10-8) and BLCA (P < 5 × 10-6) were identified as instrumental variables and assessed using GWAS summary data (BPH, 4,670 cases vs. 458,340 controls; BLCA, 1,279 cases vs. 372,016 controls). BPH exhibited a positive effect on the occurrence of BLCA (inverse variance weighted (IVW), odds ratio (OR) = 1.095, 95% confidence interval (CI) = 1.030-1.165, p = 0.003), but there was no causal effect for BLCA on BPH (IVW, OR = 1.092, 95% CI = 0.814-1.465, p = 0.554). Conclusion: Genetically predicted BPH was associated with a higher risk of BLCA in all histological subtypes. In contrast, the evidence was not significant to back the causality of genetically induced BLCA on BPH. These findings indicate that BPH plays a key role in developing BLCA in the European population. Further studies are needed to uncover the underlying mechanisms.

Tea consumption and risk of bladder cancer in the Bladder Cancer Epidemiology and Nutritional Determinants (BLEND) Study: Pooled analysis of 12 international cohort studies

BACKGROUND & AIMS

Tea has been shown to be associated with reduced risk of several diseases including cardiovascular diseases, stroke, metabolic syndrome, and obesity. However, the results on the relationship between tea consumption and bladder cancer are conflicting. This research aimed to assess the association between tea consumption and risk of bladder cancer using a pooled analysis of prospective cohort data.

METHODS

Individual data from 532,949 participants in 12 cohort studies, were pooled for analyses. Cox regression models stratified by study centre was used to estimate hazard ratios (HR) and corresponding 95% CIs. Fractional polynomial regression models were used to examine the dose-response relationship.

RESULTS

A higher level of tea consumption was associated with lower risk of bladder cancer incidence (compared with no tea consumption: HR = 0.87, 95% C.I. = 0.77-0.98 for low consumption; HR = 0.86, 95% C.I. = 0.77-0.96 for moderate consumption; HR = 0.84, 95% C.I. = 0.75-0.95 for high consumption). When stratified by sex and smoking status, this reduced risk was statistically significant among men and current and former smokers. In addition, dose-response analyses showed a lower bladder cancer risk with increment of 100 ml of tea consumption per day (HR-increment = 0.97; 95% CI = 0.96-0.98). A similar inverse association was found among males, current and former smokers while never smokers and females showed non-significant results, suggesting potential sex-dependent effect.

CONCLUSIONS

Higher consumption of tea is associated with reduced risk of bladder cancer with potential interaction with sex and smoking status. Further studies are needed to clarify the mechanisms for a protective effect of tea (e.g. inhibition of the survival and proliferation of cancer cells and anti-inflammatory mechanisms) and its interaction with smoking and sex.

Fluid intake and clinicopathological characteristics of bladder cancer: the West Midlands Bladder Cancer Prognosis Programme

OBJECTIVE

Between 10 and 20% of bladder cancer patients who are diagnosed with nonmuscle-invasive bladder cancer will progress to muscle-invasive disease. Risk of progression depends on several factors at diagnosis including age, tumour stage, grade, size and number, and the presence or absence of carcinoma in situ. Fluid intake may be related to these factors.

METHODS

Data of 1123 participants from the West Midlands Bladder Cancer Prognosis Programme were used. Data collection was via a semistructured questionnaire, and case report forms were used to collect clinicopathological data. Fluid intake was measured for six main categories: alcoholic fluids, hot fluids, fruit fluids, milk, fizzy drinks, and water, and converted into quintile variables. Multilevel mixed-effects linear regression was performed for every beverage category per clinicopathological variable and corrected for age, gender, and smoking status.

RESULTS

Age at diagnosis was distributed differently amongst those in different total fluid intake quintiles (predicted means 71.5, 70.9, 71.5, 69.9, and 67.4, respectively) and showed a significant inverse linear trend in alcohol (P < 0.01), hot fluids (P < 0.01), and total fluids intake (P < 0.01), in nonmuscle-invasive bladder cancer patients.

CONCLUSION

Our results suggest an inverse association for alcohol intake and total fluid intake with age at diagnosis. These results should be confirmed by future studies, alongside a possible (biological) mechanism that could influence tumour growth, and the effect of micturition frequency.

Delaying voiding, limiting fluids, urinary symptoms, and work productivity: A survey of female nurses and midwives

AIM

To examine the relationships between workplace bladder practices, urinary symptoms, and work productivity.

DESIGN

Cross-sectional observational survey.

METHODS

Surveys were distributed June-November 2016 to at least 600 female nurses and midwives at three urban hospitals in New South Wales, Australia. Nurses self-reported restricted workplace access to toilets, delaying voiding, limiting of fluid intakes and urinary symptoms at work. Logistic modelling was used to examine whether nurses' bladder practices impaired their time management, ability to concentrate or perform physical demands.

RESULTS

Of 353 useable surveys, one in five nurses (22.4%; N = 79) reported restricted access to toilets at work, most (77.1%; N = 272) delayed voiding and one in four (26.9%; N = 95) limited fluid intakes to delay voiding at work. Almost half the sample had urinary symptoms at work (46.7%; N = 165); delaying voiding increased the likelihood of impaired mental concentration and limiting fluid intakes increased the likelihood of impaired time management.

CONCLUSION

As workplace access to toilets and related bladder practices are modifiable, associated urinary symptoms and productivity loss may be preventable.

IMPACT

Nurses' often experience restricted accesses to amenities due to job demands and workplace environments. The impact of nurses' poor bladder practices in the workplace is not known. In this study most nurses delayed voiding and many purposefully limited fluid intakes at work. These behaviours impacted a nurse's ability to manage time and/or concentrate at work. Results have implications for nurses' personal health, the design of workplace environments, workforce management, occupational health policy, and patient care.

Epidemiology of Bladder Cancer: A Systematic Review and Contemporary Update of Risk Factors in 2018

CONTEXT

Bladder cancer (BC) is a significant health problem, and understanding the risk factors for this disease could improve prevention and early detection.

OBJECTIVE

To provide a systematic review and summary of novel developments in epidemiology and risk factors for BC.

EVIDENCE ACQUISITION

A systematic review of original articles was performed by two pairs of reviewers (M.G.C., I.J., F.E., and K.P.) using PubMed/Medline in December 2017, updated in April 2018. To address our primary objective of reporting contemporary studies, we restricted our search to include studies from the last 5yr. We subdivided our review according to specific risk factors (PICO [Population Intervention Comparator Outcome]).

EVIDENCE SYNTHESIS

Our search found 2191 articles, of which 279 full-text manuscripts were included. We separated our manuscripts by the specific risk factor they addressed (PICO). According to GLOBOCAN estimates, there were 430000 new BC cases and 165000 deaths worldwide in 2012. Tobacco smoking and occupational exposure to carcinogens remain the factors with the highest attributable risk. The literature was limited by heterogeneity of data.

CONCLUSIONS

Evidence is emerging regarding gene-environment interactions, particularly for tobacco and occupational exposures. In some populations, incidence rates are declining, which may reflect a decrease in smoking. Standardisation of reporting may help improve epidemiologic evaluation of risk.

PATIENT SUMMARY

Bladder cancer is common worldwide, and the main risk factors are tobacco smoking and exposure to certain chemicals in the working and general environments. There is ongoing research to identify and reduce risk factors, as well as to understand the impact of genetics on bladder cancer risk.

Association of benign prostatic hyperplasia and subsequent risk of bladder cancer: an Asian population cohort study

OBJECTIVES

Few studies discussed the link between benign prostatic hyperplasia (BPH) and bladder cancer. We performed this cohort study to investigate whether there is an association between BPH and subsequent risk of bladder cancer.

METHODS

We identified 35,092 study subjects including 17546 BPH patients and 17546 comparisons from the National Health Insurance database. The comparison cohort was frequency matched with age and index-year. We measured subsequent bladder cancer rates (per 1000 person-years) in two cohorts. Attributable risks (ARs) was calculated based on the bladder cancer rates in two cohorts. The hazard ratios (HRs) and 95% confidence intervals (CIs) for bladder cancer were estimated via Cox proportional hazard regression.

RESULTS

BPH patients had a higher bladder cancer rate than comparisons (AR = 0.81 per 1000 person-years) and exhibited 4.69- and 4.11-fold increases in bladder cancer risk in the crude and adjusted Cox models, respectively (95% CIs = 4.15-6.99 and 2.70-6.26). The AR was highest in patients aged 65-74 years old (AR = 1.33). BPH patients with chronic kidney disease were at an elevated bladder cancer risk. Regarding the association between bladder cancer and transurethral prostatectomy (TURP), BPH patients who underwent TURP were at a higher risk of bladder cancer (AR = 1.69; HR = 6.17, 95% CI = 3.68-10.3) than those who did not (AR = 0.69; HR = 3.73, 95% CI = 2.43-5.74).

CONCLUSIONS

In this study, BPH patients were found to have an increased risk of subsequent bladder cancer. Based on the limitations of retrospective nature, further studies are needed.

Fluid intake-to-bed time, nocturia frequency and the risk of urothelial carcinoma of the bladder: a case-control study

Objectives: To clarify the potential role of fluid intake-to-bed time and nocturia frequency on bladder cancer risk in a hospital-based case-control study with Chinese people.

Materials and Methods: Four hundred and seven patients with histologically diagnosed bladder cancer and 400 matched controls were enrolled in this study. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression model.

Results: After adjustment for potential confounders, the fluid intake-to-bed time was associated with a decreased risk of BCa, with an OR of 0.586 (95% CI= 0.375-0.916, ≤1h) and 0.257 (95% CI= 0.162-0.407, >1h). The adjusted OR of BCa for subjects with more nocturia frequency (≥2 times) was 2.268 (95 % CI= 1.481-3474), compared to those with no nocturia.

Conclusion: We suggested strong protective effect of long fluid intake-to-bed time on BCa risk, especially in ones with ≥2 times nocturia frequency. These results provide evidence for identifying high-risk individuals and modifying their behaviors and lifestyle.

Alcohol consumption and risk of urothelial cell bladder cancer in the European prospective investigation into cancer and nutrition cohort

Findings on the association between alcohol consumption and bladder cancer are inconsistent. We investigated that association in the European Prospective Investigation into Cancer and Nutrition cohort. We included 476,160 individuals mostly aged 35-70 years, enrolled in ten countries and followed for 13.9 years on average. Hazard ratios (HR) for developing urothelial cell carcinoma (UCC; 1,802 incident cases) were calculated using Cox proportional hazards models. Alcohol consumption at baseline and over the life course was analyzed, as well as different types of beverages (beer, wine, spirits). Baseline alcohol intake was associated with a statistically nonsignificant increased risk of UCC (HR 1.03; 95% confidence interval (CI) 1.00-1.06 for each additional 12 g/day). HR in smokers was 1.04 (95% CI 1.01-1.07). Men reporting high baseline intakes of alcohol (>96 g/day) had an increased risk of UCC (HR 1.57; 95% CI 1.03-2.40) compared to those reporting moderate intakes (<6 g/day), but no dose-response relationship emerged. In men, an increased risk of aggressive forms of UCC was observed even at lower doses (>6 to 24 g/day). Average lifelong alcohol intake was not associated with the risk of UCC, however intakes of spirits > 24 g/day were associated with an increased risk of UCC in men (1.38; 95% CI 1.01-1.91) and smokers (1.39; 95% CI 1.01-1.92), compared to moderate intakes. We found no association between alcohol and UCC in women and never smokers. In conclusion, we observed some associations between alcohol and UCC in men and in smokers, possibly because of residual confounding by tobacco smoking.

Total fluid consumption and risk of bladder cancer: a meta-analysis with updated data

With meta-analysis we tented to reveal the potential relationship between daily fluid consumption and bladder cancer risk, and to find out a recommendation on daily fluid intake. Databases of the Web of Science, PubMed and EMBASE were searched then 21 case-control and 5 cohort studies were included. Stratified analyses on gender, region, time of subjects recruiting and fluid quantity were performed as well as dose-response meta-analysis. Comparing the highest exposure category with the lowest in each study, no association appeared when all data pooled together (p=0.50), but a significant OR of 1.46 (1.02-2.08, p=0.04) was found in male subgroup. For different regions, the summarized OR was 1.44 (1.10-1.89) in American case-control studies, 1.87 (1.20-2.90) in European male subgroup and 0.24 (0.10-0.60) in Asia. There was a significant relationship that each increment 1000ml daily consumption would increase the risk by 28.6% in European male (p=0.007). Similarly every additional 1000ml consumption may increase the OR by 14.9% in American people but the association wasn't that strong (p=0.057). Stratified analyses showed fluid consumption over 3000ml/day in American residents and 2000ml/day in European male resulted in OR>1 with statistical significance. In conclusion, a relationship between higher fluid intake and higher bladder cancer risk was observed in European male and American residents and a limitation to <2000ml and <3000ml per day are recommended respectively.

Dietary water intake and bladder cancer risk: An Italian case-control study

Previous studies on the relationship between fluid intake and risk of bladder cancer have generally focused on beverages, and results have been inconsistent. We investigated the relationship between water intake and bladder cancer risk, considering water from both beverages and foods. Between 2003 and 2014 we conducted a multicenter hospital-based case-control study in Italy on 690 cases and 665 frequency-matched controls. Water intake for beverages and foods was computed using the Italian food composition database. Odds ratios (ORs) and the corresponding 95% confidence intervals (95%CIs) for water intake were estimated by unconditional multiple logistic regression models, adjusting for major risk factors for bladder cancer. In the control group, the 64.7% of water intake derived from beverages and 35.4% from foods. Comparing the highest with the lowest quartile of intake, water from beverages (OR=1.14; 95%CI: 0.82-1.59) and water from foods (OR=0.88; 95%CI: 0.61-1.28) were not significantly associated with bladder cancer risk. Some specific water sources showed significant associations with bladder cancer risk (e.g. water from vegetables, OR=0.58; 95%CI: 0.40-0.86). However, these associations may be due to the effect of other components contained in beverages and foods rather than to the water content itself. Considering the intakes of water from both beverages and foods, total water intake was not associated with bladder cancer risk.

Epidemiology of bladder cancer

Bladder cancer incidence is higher in old men, shows geographic variation, and is mostly an environmental disease. Cigarette smoking, occupational exposures, water arsenic, Schistosoma haematobium infestation, and some medications are the best established risk factors. Low-penetrance genetic factors also contribute to its origin, some through interaction with environmental factors. Bladder cancer has high prevalence and a low mortality, being largely a chronic disease. Data on environmental and genetic factors involved in the disease outcome are inconclusive.

Relationship between bladder cancer and total fluid intake: a meta-analysis of epidemiological evidence

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.