Evidence map›Paper›PMID 41980087›Full record

ArticleDiabetes care2026

Seasonal BMI Amplitude and Risk of Kidney Function Decline in Japanese Adults With Type 2 Diabetes (JDDM 82).

Ryota Toki, Masaya Sakamoto, Masahiro Yuki, Miho Iida, Michiko Yamazaki, Seiichi Ichikawa, Ryuzo Horiuchi, Hiroshi Maegawa, Tomonori Okamura, Toru Takebayashi

Abstract readMulticenter Study
In one paragraph

Article in Diabetes care, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Ryota TokiDepartment of Preventive Medicine and Public Health, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.ORCID 0009-0007-3348-4645
Masaya SakamotoDepartment of Diabetes, Metabolism & Endocrinology, School of Medicine, International University of Health and Welfare, Chiba, Japan.ORCID 0000-0001-7839-0780
Masahiro YukiDepartment of Diabetes, Metabolism & Endocrinology, School of Medicine, International University of Health and Welfare, Chiba, Japan.
Miho IidaDepartment of Preventive Medicine and Public Health, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
Michiko YamazakiDepartment of Social Medical Sciences, Graduate School of Medicine, International University of Health and Welfare, Tokyo, Japan.
Seiichi IchikawaDepartment of Cardiology, Tsuruoka Kyoritsu Hospital, Tsuruoka-shi, Yamagata, Japan.
Ryuzo HoriuchiDepartment of Pathology, Tsuruoka Kyoritsu Hospital, Tsuruoka-shi, Yamagata, Japan.
Hiroshi MaegawaYasu City Hospital, Yasu-shi, Shiga, Japan.
Tomonori OkamuraDepartment of Preventive Medicine and Public Health, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
Toru TakebayashiDepartment of Preventive Medicine and Public Health, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveBody weight variability is linked to cardiometabolic outcomes, but its renal impact in type 2 diabetes remains uncertain. We tested whether the magnitude of seasonal BMI fluctuation is independently associated with kidney function decline. RESEARCH DESIGN AND

methodsWe analyzed a nationwide, multicenter Japanese cohort (2014-2020). Monthly BMI was modeled using seasonal-trend locally estimated scatterplot smoothing to quantify each participant's within-year peak-to-trough difference. The primary outcome was ≥40% decline in estimated glomerular filtration rate (eGFR). Secondary outcomes were ≥30% eGFR decline, creatinine doubling, incident chronic kidney disease (CKD) stage ≥3, and kidney failure. Associations were estimated using multivariable Cox models with clinic as a random effect.

resultsAmong 6,700 outpatients (median follow-up: 6.8 years), 779 reached the primary end point. Each 1-SD increase in BMI fluctuation was associated with higher risk of ≥40% eGFR decline (hazard ratio [HR] 1.23, 95% CI 1.16-1.31). The highest versus lowest tertile showed a 1.7-fold increased risk (HR 1.72, 95% CI 1.42-2.09). Patterns were consistent for ≥30% eGFR decline (HR 1.18, 95% CI 1.13-1.23), creatinine doubling (HR 1.30, 95% CI 1.17-1.45), and incident CKD stage ≥3 (HR 1.11, 95% CI 1.07-1.16). Longitudinal analyses showed steeper eGFR decline in the highest-fluctuation group. Results were robust across sensitivity analyses, including models for time-varying medication exposure.

conclusionsIn type 2 diabetes, larger intra-annual BMI fluctuations were independently and dose-dependently associated with kidney function decline. Seasonal BMI amplitude may identify higher-risk individuals; whether reducing seasonal BMI fluctuations improves kidney outcomes warrants prospective evaluation.

Indexed as

Body Mass IndexDiabetes Mellitus, Type 2KidneySeasonsAgedEast Asian PeopleFemaleGlomerular Filtration RateHumansJapanMaleMiddle AgedRenal Insufficiency, Chronic

Identifiers

PMID41980087
PMCPMC13191414

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.