Association between renal function and cardiovascular mortality: a retrospective cohort study of elderly from health check-up

Ying-Jhen Huang; Yu-Lin Hsu; Yung-Hsin Chuang; Hugo Y-H Lin; Yen-Hsu Chen; Ta-Chien Chan

doi:10.1136/bmjopen-2021-049307

Association between renal function and cardiovascular mortality: a retrospective cohort study of elderly from health check-up

BMJ Open. 2021 Sep 21;11(9):e049307. doi: 10.1136/bmjopen-2021-049307.

Authors

Ying-Jhen Huang¹, Yu-Lin Hsu¹, Yung-Hsin Chuang^{1

2}, Hugo Y-H Lin^{3

4

5}, Yen-Hsu Chen^{6

7

8

9}, Ta-Chien Chan^{10

2}

Affiliations

¹ Research Center for Humanities and Social Sciences, Academia Sinica, Taipei, Taiwan.
² Institute of Public Health, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.
³ Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁴ Department of Internal Medicine, Kaohsiung Municipal Ta-Tung Hospital, Kaohsiung, Taiwan.
⁵ Department of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁶ Division of Infectious Disease, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁷ School of Medicine, Graduate Institute of Medicine, Sepsis Research Center, Research Center of Tropical Medicine and Infectious Disease, Kaohsiung Medical University, Kaohsiung, Taiwan.
⁸ Institute of Medical Science and Technology, National Sun Yat-sen University, Kaohsiung, Taiwan.
⁹ Department of Biological Science and Technology, College of Biological Science and Technology, National Yang Ming Chiao Tung University, Hsinchu, Taiwan.
¹⁰ Research Center for Humanities and Social Sciences, Academia Sinica, Taipei, Taiwan dachianpig@gmail.com.

Abstract

Objectives: This study aimed to investigate the relationship between cardiovascular mortality in elderly Asians and decline in renal function.

Design: A retrospective cohort study.

Setting: Community-based health examination database from Taipei city.

Participants: At the beginning, the database included 315 045 health check-up visits of 97 803 elderly persons aged ≥65 years old from 2005 to 2012. After excluding missing values and outliers, there were 64 732 elderly persons with at least two visits retained for further analyses.

Primary outcome measures: Kidney function indicators include estimated glomerular filtration rate (eGFR) and urine protein, and rapid decline in eGFR was defined as slope ≤ -5 mL/min/1.73 m² per year. The endpoint outcome was defined as the cardiovascular deaths registered in the death registry encoded by the International Classification of Diseases. We applied a Cox proportional hazards model to analyse the association between renal function and cardiovascular mortality.

Results: In this study, we found 1264 elderly persons died from cardiovascular diseases, for whom the data included 4055 previous health check-up visits. We observed significant and independent associations of eGFR <60 mL/min/1.73 m² (HR (95% CI) of 60>eGFR≥45 and eGFR<45 in males: 2.85 (1.33 to 6.09) and 3.98 (1.84 to 8.61); in females: 3.66 (1.32 to 10.15) and 6.77 (2.41 to 18.99)), positive proteinuria (HR (95% CI) of +/-, +,++ and +++, ++++ in males: 1.51 (1.29 to 1.78) and 2.31 (1.51 to 3.53); in females: 1.93 (1.54 to 2.42) and 4.23 (2.34 to 7.65)) and rapid decline in eGFR (HR (95% CI) in males: 3.24 (2.73 to 3.85); in females: 2.83 (2.20 to 3.64) with higher risk of cardiovascular mortality. The joint effect of increased concentration of urine protein and reduced eGFR was associated with a higher risk of cardiovascular mortality.

Conclusions: Renal function and rapid decline in renal function are independent risk factors for cardiovascular mortality in the elderly.

Keywords: cardiology; chronic renal failure; epidemiology; geriatric medicine; public health.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aged
Cardiovascular Diseases*
Female
Glomerular Filtration Rate
Humans
Kidney / physiology
Male
Proteinuria
Renal Insufficiency, Chronic*
Retrospective Studies
Risk Factors