QoL is becoming a more important health issue and, in elderly men, worsened BPH-induced LUTS exacerbates QoL. Moreover, medical costs for relieving LUTS tend to be significantly increased because of its impact on QoL. However, because of the close relationship between aging and BPH/LUTS, no clear strategies for preventing the development of LUTS have been developed thus far, and prevention strategies for LUTS in men are urgently needed, as mentioned previously. In the current study, we aimed to demonstrate the impact of LUTS on QoL; based on this, we thoroughly assessed the impacts of MetS and lifestyle-related factors on LUTS to suggest the effective prevention strategies for LUTS in men to improve QoL.
Based on the current study, not only severe LUTS but also moderate LUTS affect sleep quality and stress in daily life. Moreover, the presence of LUTS was the most powerful variable associated with both sleep disturbance and stress, followed by younger age and marital status. In other words, preventing the development of moderate to severe LUTS, in addition to alleviating LUTS, could be important medical issues for improving mental health and daily QoL in men. In addition, urologists need to have more interest in mental health and daily QoL, because LUTS is one of the most important factors affecting sleep disorders and stress.
In this study, the amount of life-long smoking was significantly associated with the presence of moderate and severe LUTS, which is consistent with previous studies 15. However, the amount of life-long smoking was not associated with prostate volume. A previous study reported that nicotine might worsen LUTS by reducing bladder flow and urothelial hypoxia 15, which supports the results of the current study. Interestingly, the impact of the amount of life-long smoking, not current smoking status 16, on voiding symptoms was also observed in the current study, which supports the need for early education on the adverse effects of smoking on LUTS, although these remain to be validated in future studies. Because only a few previous studies have assessed the relationship between smoking and LUTS and these studies generally showed inconsistent results, the findings of the current study could be help clinicians and patients based on a detailed analysis of various factors related to LUTS.
In addition to age, several socioeconomic statuses, including marital status 16, income, and job, showed a close relationship with the presence of moderate to severe LUTS in this study, similar to a previous study 17. This might be due to the relationship between psychological stability and LUTS. In a previous study, satisfaction with life was reported to be associated with LUTS progression 18, which supports these results. In addition, other lifestyle factors, such as diet and behavior, which are related to marital status, income, and job, might be the reasons for the presence of moderate to severe LUTS in men with low socioeconomic status, although these cannot be revealed in the current study.
Among MetS and metabolic components, decreased HDL cholesterol was the only variable related to moderate to severe LUTS, which agrees with a previous study 9. Moreover, the presence of decreased HDL cholesterol was associated with increased prostate volume, in addition to central obesity, which is consistent with a previous study 19,20. Because the severity of LUTS is also associated with decreased HDL cholesterol, it is important to maintain an HDL-cholesterol level over 40 mg/dL. Interestingly, the presence of hypertension was negatively associated with voiding symptom severity, but not with storage symptoms. These findings might be due to the effects of alleviating LUTS by angiotensin II receptor blocker medication for hypertension as described in previous studies 21 although these need to be verified in future studies.
Based on the current study, alcohol consumption and exercise were not associated with the presence of moderate to severe LUTS in men aged ≥ 40 years. In other words, the prevention of moderate to severe LUTS seemed to be achieved by life-long lifestyle modification and by maintaining a stable socioeconomic status, not by short-term daily life modification. However, because alcohol consumption and exercise were determined as factors associated with decreased sleep disorder and moderate to severe stress, the importance of appropriate alcohol consumption restriction and daily exercise to improve QoL should not be overlooked, especially in men with moderate to severe LUTS.
The current study was limited by its cross-sectional study design, although a large number of men who underwent routine health check-ups were included in the analysis. In addition, because of the study design, we could only suggest the relationship between lifestyle and MetS-related variables with the presence of moderate to severe LUTS, and the causality needs to be verified in future studies. However, to our knowledge, this is the first large study to thoroughly assess the relationship not only between LUTS and lifestyle and MetS-related variables, but also between prostate volume and lifestyle and MetS-related variables. Moreover, we assessed its impact on sleep disorders and moderate to severe stress in daily life. Therefore, this study could be useful for clinicians when counselling men, who are not only worried about or experiencing moderate to severe LUTS, but are also having sleep disorders and moderate to severe stress.
In conclusions, in men aged ≥ 40 years, stable socioeconomic status, including married marital status, office worker, and high income, are negatively associated with the presence of moderate to severe LUTS, which worsens sleep quality and stress level. In addition, quitting smoking and maintaining HDL cholesterol levels over 40 mg/dL might be effective lifestyle modification strategies for preventing moderate to severe LUTS. Maintaining HDL cholesterol levels, in addition to decreasing waist circumference, could also be effective in preventing prostate enlargement.