Independent and interactive effects of kidney stone formation and conventional risk factors for chronic kidney disease: a follow-up study of Japanese men.

To assess the impact of interactions between kidney stone formation and conventional risk factors on incident chronic kidney disease (CKD).

A total of 11,402 subjects (men 30-69 years of age, Japanese) without CKD at baseline were observed over an average period of 4 years. Cox proportional hazards regression models were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) to determine the association between incident CKD, kidney stone formation, and conventional risk factors (diabetes mellitus, hypertension, overweight/obesity, dyslipidemia, and hyperuricemia/gout). We also examined the interactions of renal stones and the conventional risk factors for CKD.

In total, 2301 men (20.2%) developed incident CKD during the follow-up period. After multivariable adjustment, kidney stones were found to increase the risk of incident CKD (HR 1.16; 95% CI 1.03-1.32). Kidney stone formers with hypertension, dyslipidemia, or hyperuricemia/gout presented a greater risk for incident CKD than those who had either kidney stones or other risk factors. However, no significant interactions between kidney stones and other risk factors were found to increase CKD risk. On the other hand, a negative interactive effect between kidney stones and overweight/obesity was observed, leading to reversed risk of incident CKD in coexistence of both factors.

Kidney stones were linked to a higher risk for the development of CKD. However, no positive interactive effects were identified between renal stones and conventional risk factors on the risk of incident CKD.

International urology and nephrology. 2021 Feb 24 [Epub ahead of print]

Ryosuke Ando, Teruo Nagaya, Sadao Suzuki, Hidekatsu Takahashi, Makoto Kawai, Kazumi Taguchi, Shuzo Hamamoto, Atsushi Okada, Takahiro Yasui

Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, 1, Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan. ., Department of Public Health, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan., Gifu Prefectural Center for Health Check and Health Promotion, Gifu, Japan., Department of Nephro-urology, Nagoya City University Graduate School of Medical Sciences, 1, Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan.