Abstract
Aims
The aim of this cohort study was to evaluate the association between urinary levels of C-megalin, a full-length form of megalin, and kidney dysfunction progression and its dependence on the urinary albumin-creatinine ratio (UACR) in individuals with diabetes.
Methods
We enrolled 1,547 individuals with diabetes who visited the ambulatory clinic at Tenri Hospital, a regional tertiary-care hospital in Tenri City, Nara Prefecture, Japan, with an estimated glomerular filtration (eGFR) of ≥ 30 mL/min/1.73 m2. The hazard ratio (HR) and 95% confidence interval (CI) were estimated using Cox proportional hazard models to examine the association between urinary C-megalin levels and eGFR decline by ≥ 40% from baseline.
Results
Urinary C-megalin level was not associated with ≥ 40% eGFR decline in an age-, sex-, eGFR-, systolic blood pressure-, hemoglobin-, and UACR-adjusted model in the 1,547 patients enrolled in the study. However, urinary C-megalin levels were associated with a ≥ 40% decline in eGFR when accounting for the relationship between urinary C-megalin levels and UACR in the model. This association was UACR-dependent.
Conclusions
High urinary C-megalin levels were associated with progressive kidney dysfunction in individuals with diabetes, and this association was attenuated by high UACRs.
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Data availability
The datasets generated during and/or analyzed during the current study are not publicly available due to the need for participant privacy but are available from the corresponding author upon reasonable request.
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Acknowledgements
Members of the Diabetes Distress and Care Registry at Tenri Study Group: Hitoshi Ishii and Hirohito Kuwata (Department of Diabetology, Nara Medical University); Maki Fujimura, Kiyoko Takano, Satoru Tsujii, Shintaro Okamura, Satoshi Matsunaga, Yasuaki Hayashino, and Masako Kitatani (Department of Endocrinology, Tenriyorozu Hospital); Mako Kitatani (Shirakawa Branch, Tenri Hospital); Satoshi Matsunaga (Department of Hematology, Endocrinology and Metabolism, Niigata University Faculty of Medicine); Yaeko Kondo (Department of Diabetes and Clinical Nutrition, Kyoto University); Naotaka Fujita (Otsu Red Cross Hospital); Rei Ueda (Second Department of Internal Medicine, Faculty of Medicine, University of the Ryukyus); Rie Kawata (Sawa Hospital); Masami Tanaka (Tokyo Women’s Medical University Medical Center East); Tsuyoshi Mashitani (Mashitani Clinic); and Miyuki Furuya (Furuya Clinic). We would like to thank Yukari Moritsuji, Yuki Fujita, Noriko Nakamura, and Yoko Sakamoto (Department of Endocrinology, Tenri Hospital) for their clerical support. This study was funded by the Manpei Suzuki Diabetes Foundation and the Japan Society for the Promotion of Science (JSPS) KAKENHI [grant numbers 25460641 and 16K08897]. The funders played no role in designing the study; in collecting, analyzing, or interpreting the data; in writing the manuscript; and in the decision to submit the article for publication.
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Conceptualization: NK; methodology: KN, HN, and NK; investigation: MK, KK, YS, SM, SO, ST, and YH; formal analysis: KN, HN, and NK; writing—original draft preparation: KN, HN, and NK; writing—review and editing: YH and NK; funding acquisition: YH; resources: NK, MK, KK, YS, SM, SO, ST, and YH; supervision: YH and NK.
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Kakuya Niihata, Hiroki Nishiwaki, Maki Kinoshita, Kentaro Kurosawa, Yui Sakuramachi, Satoshi Matsunaga, Shintaro Okamura, Satoru Tsujii, and Yasuaki Hayashino declare that they have no conflicts of interest. Noriaki Kurita has served as a senior scientist at the Institute for Health Outcomes and Process Evaluation Research (iHope International, a non-profit organization), but was not compensated for his contribution to this study. Denka Seiken Co., Ltd., measured urinary C-megalin; however, the company had no role in designing the study; in collecting, analyzing, or interpretating the data; in writing the manuscript; and in the decision to submit the article for publication. Denka Seiken Co., Ltd., contracted this study to iHope International.
Human and animals rights
This study conformed to the tenets of the Declaration of Helsinki and was approved by the institutional review boards of Tenri Hospital (approval no. 785) and Fukushima Medical University (approval no. 2966).
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All patients provided informed consent to participate in this study.
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This article belongs to the topical collection Diabetic Nephropathy, managed by Giuseppe Pugliese.
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Niihata, K., Nishiwaki, H., Kinoshita, M. et al. Association between urinary C-megalin levels and progressive kidney dysfunction: a cohort study based on the diabetes distress and care registry at Tenri (DDCRT 24). Acta Diabetol 60, 1643–1650 (2023). https://doi.org/10.1007/s00592-023-02144-6
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DOI: https://doi.org/10.1007/s00592-023-02144-6