As the Scientific Committee meet to conclude the final programme for ICS 2016 we bring you a fascinating insight into the main State of the Art Lecture in Tokyo. Osamu Yokoyama from the University of Fukui, Japan will provide the opening speech at ICS 2016 and he has provided the following article on the central theme of his research.
Central obesity is associated with higher risks of heart disease, hypertension (HT), and insulin resistance. Increasing evidence has pointed to a relationship between lower urinary tract symptoms (LUTS) and the presence of metabolic syndrome (MetS). This relationship has been supported by recent epidemiologic findings.1,2
In Japan, however, the relationship between LUTS and the presence of MetS is open to question. In one Japanese study, MetS was shown to have a significant negative association with the total overactive bladder symptom score (OABSS).3 The same associations have been suggested in Korea and China.4,5 The negative relationship might be due to racial differences, and the decrease in obesity with age in Asia. The Japanese Ministry of Health, Labor and Welfare estimates the prevalence of obesity (BMI > 25) in the male population to be as high as 30%; however, the prevalence of extreme obesity (BMI > 30) is markedly lower in Asia than in US and Europe. Even if the prevalence of obesity is relatively low in Japan, those of lifestyle-related diseases such as HT and diabetes are as high as in US and Europe.
According to a population-based study, LUTS is an important part of the symptomatology of HT, diabetes and neurological disease. Among lifestyle-related diseases, HT is one of the risk factors for worsening LUTS.6 Spontaneous hypertensive rats provide a genetic model for exploring the pathogenesis of urine storage dysfunction related to HT.7 In humans, however, HT develops by both genetic and environmental factors including lifestyle factors such as a high-calorie diet, excessive salt intake and stress. We investigated the influence of salt-loading on bladder function in rats and the underlying mechanisms of storage dysfunction related to HT.8
In individual LUTS, the most bothersome symptom is nocturia. The possible diseases or disorders that induce nocturia include OAB, nocturnal polyuria, and sleep disturbance. Treatment for nocturia may fail due to an often overlooked component of nocturnal urine overproduction. To investigate the relationship between HT and nocturnal polyuria in patients with OAB, multi-center cross-sectional study (OASIS Project) was conducted in Japan. In results, nocturnal polyuria was significantly associated with HT and heart rate in females and LUTS/BPH in males. Untreated HT may be a risk factor for nocturnal polyuria especially in female patients with OAB.
Understanding the underlying relationship between lifestyle-related diseases and LUTS may lead to the development of new strategies for preventing and/or treating LUTS.
- Int J Obes (Lond) 29: 310, 2005
- J Urol 182: 616, 2009
- Urology 79: 1372, 2012
- Urology 72: 556,2008
- Urology 80: 1093, 2012
- Int J Urol 10: 569, 2003
- Exp Physiol 84: 137, 1999
- Life Sci 141: 8, 2015
View the ICS 2016 Scientific Programme Register