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.