OBJECTIVE: To assess the relationship of nocturia and sleep to body weight.
MATERIALS AND METHODS: A questionnaire survey among all (n = 10216) members of a pensioners'association in the Swedish counties of Västerbotten and Norrbotten.
Results: A total of 6103 evaluable questionnaires were received, of which 39.5% were from men. The response rate was 61.3%. The ages of the male and female participants were 73.0 (6.0) [mean (SD)] and 72.6 (6.7) years, respectively. Body mass index (BMI) was 25.4 (3.1) in men and 25.4 (3.7) in women. BMI increased in parallel with increasing number of nocturnal micturition episodes in women, while the corresponding increase in men did not reach statistical significance (p = 0.10). The habit of nocturnal eating and the occurrence of poor appetite in the daytime increased in parallel with increasing number of nocturnal micturition episodes in both men and women.
CONCLUSION: Obesity increased in parallel with increased nocturnal voiding, and both nocturnal eating and daytime loss of appetite increased correspondingly. The pattern of increase of these symptoms may support the interpretation that frequent nocturnal micturition increases the risk of obesity, partly as a consequence of its negative impact on sleep.