Debra Silverman, ScD, ScM
Debra Silverman, ScD, ScM, chief of the Occupational and Environmental Epidemiology Branch and senior investigator in the Division of Cancer Epidemiology & Genetics, National Cancer Institute.
If you’re visiting the loo several times during the night, it may be some comfort to know that frequent nocturnal urination is associated with lower rates of bladder cancer.
According to statistics released by the National Cancer Institute, almost 69,000 new cases of bladder cancer were diagnosed last year. Men are about three to four times more likely to contract bladder cancer, though it occurs in women as well. A study recently published in the International Journal of Cancer strongly suggests that urinating during the night can dramatically reduce your chances of getting bladder cancer.
First author on the study, Debra Silverman, ScD, ScM, chief of the Occupational and Environmental Epidemiology Branch and a senior investigator in the Division of Cancer Epidemiology & Genetics at the National Cancer Institute, told me the research took place in 18 hospitals in Spain over a three-year period. Investigators identified 884 newly diagnosed bladder cancer patients of both genders, ranging in age from 21 to 80 and also, from the same hospitals, drew a control group of 996 patients with illnesses not related to the factors under investigation. This group was matched to bladder cancer patients on age, gender, race and ethnicity. Patients in both groups were then questioned about their medical history and that of other family members, as well as their lifestyle habits, including diet, fluid consumption, medications and smoking habits. They were asked to recall how many times they typically urinated, day and night, in a 24-hour period.
The study found that urinating at least twice during the night was associated with a decreased risk of bladder cancer. Men who habitually did so lowered their risk by 40%, women by 50%. Even for smokers (who have a high rate of bladder cancers), frequent nocturnal urination reduced bladder cancer risk by 50%. “Our hypothesis is that increased urination frequency decreases the amount of time that urine containing carcinogens from smoking are in direct contact with the tissue that lines the urinary bladder,” Dr. Silverman said, adding that water consumption, too, was separately associated with reduced risk for bladder cancer.
Bladder cancer is a serious disease, says Dr. Silverman, but it tends not to get as much attention in the media as some other cancers because it’s much more likely to be caught early and treated successfully — probably because the usual first symptom is blood in the urine, which is easy to see and alarming enough to send you to your doctor immediately.
Emphasizing that more research needs to be done before any definitive conclusions can be drawn about the effect of sleep-time bathroom visits, Dr. Silverman notes that there is one thing you can do right away to dramatically lower the risk of bladder cancer. “Don’t smoke. We haven’t fully identified all the different carcinogens in tobacco smoke that increase risk, but there’s no doubt that smoking is the main risk factor for bladder cancer,” she says. “If you need yet another reason not to take up smoking, or to quit if you’re already a smoker, this is it.”