Shinichi Sakamoto1, Katsuhito Miyazawa2, Takahiro Yasui3, Taro Iguchi4, Misuzu Fujita5, Hiroaki Nishimatsu6, Takuro Masaki7, Toru Hasegawa8, Hatsuki Hibi9, Takashi Arakawa10, Ryosuke Ando3, Yoshinari Kato11, Noritaka Ishito12, Satoshi Yamaguchi13, Ryoji Takazawa14, Masao Tsujihata15, Tadashi Matsuda16, Koichiro Akakura17, Akira Hata5, Tomohiko Ichikawa1. 1. Department of Urology, Graduate School of Medicine, Chiba University, Chiba, Japan. 2. Department of Urology, Kanazawa Medical University, Uchinada, Ishikawa, Japan. 3. Department of Nephro-Urology, Graduate School of Medical Sciences, Nagoya City University, Nagoya, Aichi, Japan. 4. Department of Urology, Osaka City University Graduate School of Medicine, Osaka, Japan. 5. Department of Public Health, Graduate School of Medicine, Chiba University, Chiba, Japan. 6. Department of Urology, Doai Memorial Hospital, Tokyo, Japan. 7. Department of Urology, Harasanshin Hospital, Fukuoka, Japan. 8. Department of Urology, Hasegawa Hospital, Tokyo, Japan. 9. Department of Urology, Kyoritsu General Hospital, Nagoya, Aichi, Japan. 10. Department of Urology, International University of Health and Welfare Mita Hospital, Tokyo, Japan. 11. Department of Urology, Kaizuka City Hospital, Osaka, Japan. 12. Department of Urology, Kurashiki Medical Center, Kurashiki, Okayama, Japan. 13. Department of Urology, Kitasaito Hospital, Sagamihara, Kanagawa, Japan. 14. Department of Urology, Tokyo Metropolitan Ohtsuka Hospital, Tokyo, Japan. 15. Department of Urology, Osaka Rosai Hospital, Sakai, Osaka, Japan. 16. Department of Urology and Andrology, Kansai Medical University, Hirakata, Osaka, Japan. 17. Department of Urology, JCHO Tokyo Shinjuku Medical Center, Tokyo, Japan.
Abstract
OBJECTIVES: To assess epidemiological and chronological trends of upper urinary tract stones in Japan in 2015. METHODS: Patients with a first episode of upper urinary tract stones in 2015 were enrolled in this nationwide survey. The study included all hospitals approved by the Japanese Board of Urology, therefore covering most of the hospitals where urologists practice in Japan. The annual incidence and composition of urolithiasis were evaluated by age and sex. These results were compared with the previous results of the nationwide surveys from 1965 to 2005 to analyze temporal trends. RESULTS: The estimated annual incidence of a first-episode upper urinary tract stone in 2015 was 137.9 (191.9 in men and 86.9 in women) per 100 000. The estimated age-standardized first-episode upper urinary tract stone incidence in 2015 was 107.8 (150.6 in men and 63.3 in women) per 100 000, which did not represent a significant increase since 2005. An equivalent incidence was observed in patients aged >50 years, whereas a reduced incidence was observed in patients aged <50 years in both sexes. The proportion of patients who received percutaneous nephrolithotomy and/or ureteroscopy increased by approximately fivefold in the past 10 years. CONCLUSIONS: The steady increase in the annual incidence of upper urinary tract stones since 1955 leveled off in 2015. The current results show novel trends in the incidence and treatment modalities in the nationwide surveys of urolithiasis in Japan.
OBJECTIVES: To assess epidemiological and chronological trends of upper urinary tract stones in Japan in 2015. METHODS:Patients with a first episode of upper urinary tract stones in 2015 were enrolled in this nationwide survey. The study included all hospitals approved by the Japanese Board of Urology, therefore covering most of the hospitals where urologists practice in Japan. The annual incidence and composition of urolithiasis were evaluated by age and sex. These results were compared with the previous results of the nationwide surveys from 1965 to 2005 to analyze temporal trends. RESULTS: The estimated annual incidence of a first-episode upper urinary tract stone in 2015 was 137.9 (191.9 in men and 86.9 in women) per 100 000. The estimated age-standardized first-episode upper urinary tract stone incidence in 2015 was 107.8 (150.6 in men and 63.3 in women) per 100 000, which did not represent a significant increase since 2005. An equivalent incidence was observed in patients aged >50 years, whereas a reduced incidence was observed in patients aged <50 years in both sexes. The proportion of patients who received percutaneous nephrolithotomy and/or ureteroscopy increased by approximately fivefold in the past 10 years. CONCLUSIONS: The steady increase in the annual incidence of upper urinary tract stones since 1955 leveled off in 2015. The current results show novel trends in the incidence and treatment modalities in the nationwide surveys of urolithiasis in Japan.