Major Finding: Women who are current smokers are 3 times as likely to report problems with urinary frequency and 2.7 times as likely to report problems with urinary urgency as women who do not smoke.
Data Source: Population-based study of a representative sample of 1,790 Finnish women.
Disclosures: Dr. Tikkinen said that he had no conflicts. Pirkanmaa Hospital District and Pfizer funded the study through unrestricted grants.
SAN FRANCISCO — A Finnish study has found a strong association between tobacco smoking and urinary storage symptoms in women.
Women who smoke are 3 times as likely to report abnormal urinary frequency and 2.7 times as likely to report abnormal urinary urgency, compared with nonsmokers, Dr. Kari A.O. Tikkinen of Helsinki University Central Hospital said at the meeting.
The study involved survey responses from a nationally representative sample of 1,790 Finnish women aged 18-79 years (mean age 42 years). Investigators assessed urinary symptoms from responses to questions on the American Urological Association Symptom Index and the Danish Prostatic Symptom Score questionnaires.
In addition to urinary frequency and urgency, the women were asked about nocturia, stress incontinence, and urgency incontinence. The researchers found that only frequency and urgency were significantly associated with smoking.
They defined urinary frequency as abnormal if the women reported their longest interval between each urination was less than 2 hours. They defined abnormal urgency as often or always experiencing an imperative urge to urinate, nocturia as two or more voids per night, stress incontinence as often or always experiencing leakage of urine when physically active, and urgency incontinence as often or always experiencing an urge so strong that urine starts to flow before reaching the toilet.
In the multivariate analysis, the researchers controlled for a large number of potential confounders. These included 33 different physician-diagnosed medical conditions, 26 different classes of prescription medications, lifestyle and social demographic factors such as education and income, and anthropometric and reproductive factors such as body mass index and menopausal status.
About half of the women had never smoked, a quarter were current smokers, and a quarter were former smokers. The former smokers also had a significantly higher risk of abnormal urinary frequency and urgency than the never smokers, although not to the extent of current smokers. They were 70% more likely to experience abnormal frequency and 80% more likely to experience abnormal urgency than never smokers.
The researchers also found a dose-response effect. Compared with light smokers (1-10 cigarettes per day), heavy smokers (10 or more cigarettes per day) were 2.2 times as likely to experience abnormal frequency and 2.1 times as likely to experience abnormal urgency.
Studies such as this can only show association, not causation, but Dr. Tikkinen said at a press briefing the fact that the reasearchers controlled for so many potential confounders strengthens the case for causation.