Lower urinary tract symptoms (LUTS) affect over half of the adults’ population worldwide, with an increasing prevalence among the older age groups. Therefore, with the increasing elderly population, LUTS is an important disease, highlighting the need for accurate data on its prevalence. This present study aimed to investigate the prevalence of LUTS in South Korea.

The study targeted individuals aged at least 19 years nationwide. We conducted computer-assisted telephone interviews, 80% mobile random digital dialing (RDD) sampling frame, and 20% landline RDD sampling frame between April and
May 2020. Questionnaires included The International Prostate Symptom Score (IPSS), the overactive bladder symptom score
(OABSS), and the characteristics of respondents. Current International Continence Society definitions were used for individual LUTS and OAB

There were 2,000 respondents, 1,009 (50.4%) were women and 546 (27.3%) were aged ≥60 years. The characteristics of respondents according to the stratum are shown in Table 1. Results of the IPSS questionnaire survey showed that 77.9% had
LUTS, among them, 63.7% had mild symptoms (1–7), 11.7% had moderate symptoms (8–19), and 2.4% had severe symptoms (20–35). Symptoms tended to increase and worsen with age; LUTS was present in 72.9% of the participants under the age of 60, and 89% of those over 60. Of the reported LUTS, nocturia (50.2%) and frequency (49.6%) were the most frequent, followed by weak stream (29.6%), incomplete emptying (27.7%), intermittency (22.7%), and straining (14.6%). Obstructive symptoms were more common in men while the prevalence of storage symptoms was the same in both men and women.
The prevalence of OAB, as determined by the OABSS, was 9.6%, among the males were 10.3% and females were 9.0%. The prevalence of OAB in those under the age of 60 was 8% and 13.4% in those over the age of 60. The prevalence and severity of OAB increased with age, especially after 40 years. The most prevalent symptom among the OAB symptoms was nocturia (men, 48.3%; women, 52.5%).

This study is a population-based survey aimed at estimating the prevalence of LUTS and OAB in South Korea using the IPSS and OABSS questionnaire methods. 
Based on our survey results, 77.9% of the Korean adult population (over the age of 19) experienced at least one lower urinary tract symptom, with severity increasing with age. The prevalence rate of OAB was 9.6%. Since the population structure changes as time changes, the prevalence of LUTS is also likely to change with time; therefore, we recommend periodic LUTS and OAB prevalence investigations.

Based on our survey results, 77.9% of the Korean adult population (over the age of 19) experienced at least one
LUTS, and the severity increased with age. The prevalence and severity of OAB increased with age, especially after 40 years;
the prevalence of OAB was 9.6%, and 13.4% of them were over 60 years old.

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