Objectives: A large‐scale nationwide epidemiological survey of lower urinary tract symptoms (LUTS) was conducted via the Internet in 2023 to clarify the current prevalence of LUTS and evaluate its impact on daily life in Japan.Methods: The survey was conducted among individuals aged 20–99 years old who had anonymously registered with a Japanese online research company. The survey consisted of 48 questions related to LUTS and daily life.Results: A total of 6210 participants (3088 females and 3122 males), who were selected by probability sampling based on the composition of the Japanese population (age range: 20–99), were recruited. The overall prevalence of LUTS was 77.9% among the subjects aged ≥20 and 82.5% among those aged ≥40. The prevalence of LUTS differed between the sexes and trends toward significant increases in prevalence with age were seen for almost all LUTS. Furthermore, the prevalence of overactive bladder (OAB) was 11.9% among the subjects aged ≥20 and 13.8% among those aged ≥40. This study also showed that LUTS negatively affected daily life. However, the percentage of subjects who visited a physician to receive treatment for LUTS was low, including for participants with a history of treatment for LUTS, although this increased with age.Conclusion: The prevalence of LUTS, including OAB, increased with age and negatively affected daily life. However, since the percentage of patients who visit a physician to receive treatment for LUTS remains low, further educational activities regarding LUTS are necessary.

We identified metabolites using a metabolomics approach and investigated the association between these metabolites and lower urinary tract symptoms. We used a 24-hour bladder diary and I-PSS (International Prostate Symptom Score) to assess micturition behavior and lower urinary tract symptoms in 58 male patients without apparent neurological disease. Lower urinary tract symptoms were defined as a total I-PSS score of 8 or greater. Patients with a score of 7 or less were placed in the control group. A comprehensive study of plasma metabolites was also performed by capillary electrophoresis time-of-flight mass spectrometry. Metabolites were compared between the lower urinary tract symptoms and control groups using the Mann-Whitney U test. Biomarkers of male lower urinary tract symptoms from the metabolites were analyzed using multivariable logistic regression analysis to determine the OR. Of the 58 men 32 were in the lower urinary tract symptoms group and the remaining 26 were in the control group. The 24-hour bladder diary showed that nocturnal urine volume, 24-hour micturition frequency, nocturnal micturition frequency and the nocturia index were significantly higher in the lower urinary tract symptoms group. Metabolomics analysis identified 60 metabolites from patient plasma. Multivariate analysis revealed that increased glutamate and decreased arginine, asparagine and inosine monophosphate were significantly associated with lower urinary tract symptoms in males. Decreases in citrulline and glutamine could also be associated with male lower urinary tract symptoms. Male lower urinary tract symptoms may develop due to abnormal metabolic processes in some pathways. Potential new treatments for lower urinary tract symptoms can be developed by identifying changes in the amino acid profiles.

Sexually dimorphic brain development and behavior are known to be influenced by sex hormones exposure in prenatal periods. On the other hand, second-to forth digit ratio (2D/4D) has been used as an indirect method to investigate the putative effects of prenatal exposure to androgen. In the present study, we herein investigated the relationship between gender-role play behavior and the second-to-fourth digit ratio (2D/4D), which has been used as an indirect method to investigate the putative effects of prenatal exposure to androgens, in school-aged children. Among 4981 children who became 8 years old by November 2014 and were contactable for this survey by The Hokkaido Study of Environment and Children's Health, 1631 (32.7%), who had data for 2D/4D and Pre-school Activities Inventory (PSAI) as well as data for the survey at baseline, were available for analysis. Parents sent reports of PSAI on the sex-typical characteristics, preferred toys, and play activities of children, and black and white photocopies of the left and right hand palms via mail. PSAI consisted of 12 masculine items and 12 feminine items, and a composite score was created by subtracting the feminine score from the masculine score, with higher scores representing masculine-typical behavior. While composite scores in PSAI were significantly higher in boys than in girls, 2D/4D was significantly lower in boys than in girls. Although the presence or absence of brothers or sisters affected the composite, masculine, and feminine scored of PSAI, a multivariate regression model revealed that 2D/4D negatively correlated with the composite scores of PSAI in boys, whereas no correlation was found in girls. Although 2D/4D negatively correlated with the masculine score in boys and girls, no correlation was observed between 2D/4D and the feminine score. In conclusion, although social factors, such as the existence of brother or sisters, affect dimorphic brain development and behavior in childhood, the present study revealed that the prenatal hormonal environment was an important factor influencing masculine-typical dimorphic brain development and behavior in school-aged children.