Fluid and caffeine intake and urinary symptoms in the UK

Abstract

Overactive bladder is defined by the Standardization Subcommittee of the International Continence Society (ICS) as a bladder disease characterized by the symptoms of urinary urgency, frequency, and nocturia, with or without urgency incontinence, in the absence of urinary tract infection or other obvious pathology [1]. Current treatment strategies for this distressing disorder revolve around first-line conservativemanagement followed by specialized secondary treatment [2,3]. A primary component of first-line conservative management is the reduction of intake of bladder irritants such as caffeine-containing products, notably tea and coffee. However, there are few epidemiological studies that associate caffeine consumption with overactive bladder. The primary aim of the present study was to investigate the relationship between caffeine intake and overactive bladder in a UK population. The study was a cross-sectional survey of a predominantly local, adult female population in north London conducted using a selfadministered questionnaire. The study population included healthy female hospital workers and their female friends and relations, and the local general population. The study participants had the opportunity to complete the questionnaire online (via SurveyMonkey: www. surveymonkey.com). The questionnaire was designed to capture information on sociodemographic data; caffeine, fluid, and alcohol intake; and symptoms of overactive bladder. The study received Institutional Review Board approval. Data were analyzed using Stata statistical software, version 7.0 (StataCorp LP, College Station, TX, USA). Women with urinary frequency (passing urine 8 or more times per day) were compared with those without frequency. A similar comparison was done with urinary urgency. Differences between groups were tested for significance using the χ or Fisher exact test for categorical variables. Significant differences between groups were quantified by calculating the odds ratio (OR) and 95% confidence intervals (95% CI). P b 0.05 was considered statistically significant. Of the 2244 responses, 34% reported urinary frequency and 38% reported urinary urgency.Womenwhohad frequencywere significantly more likely to be over 55 years (P b 0.001), multiparous (P b 0.001), and smokers (P b 0.001). Table 1 shows that women in the frequency group were 3.5 times more likely to drink 6 or more cups of coffee per day (OR 3.6; 95% CI, 2.3–5.7; P b 0.001), 4 times more likely to use 3 spoonfuls or more of