Reduced Estimated GFR and Cardiac Remodeling: A Population-Based Autopsy Study

Rationale & objective: Evidence suggests that cardiac remodeling, including left ventricular hypertrophy and myocardial fibrosis, develops with progression of kidney disease. Few studies have examined cardiac pathology across a range of estimated glomerular filtration rates (eGFRs), which was the objective of this investigation.

Study design: Population-based cross-sectional study of deceased patients undergoing autopsy.

Setting & participants: 334 of 694 consecutive deceased patients undergoing autopsy with available cardiac tissue, with a prior health examination within 6 years and without a prior diagnosis of heart disease.

Exposure: eGFR.

Outcomes: The thickness of the left ventricular wall, sizes of cardiac cells, and percentages of fibrosis, estimated from pathology examination of autopsy samples.

Analytical approach: Generalized estimating equations.

Results: Lower eGFRs were associated with greater left ventricular wall thickness. Deceased patients with eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² had left ventricular wall thicknesses of 9.1, 9.5, 9.8, and 10.3mm, respectively (P for trend<0.05). Lower eGFRs were also significantly associated with greater mean values of cardiac cell size in the left ventricular wall after adjusting for confounders: 15.3, 16.1, 16.4, and 17.4μm for eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² (P for trend<0.01). Patients with lower eGFRs had significantly higher multivariable-adjusted geometric mean values for fibrosis percentage in the left ventricular wall: 3.22%, 4.33%, 3.83%, and 6.14% for eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² (P for trend<0.001). The negative association of eGFR with multivariable-adjusted mean values of cardiac cell width was stronger among patients with than those without anemia.

Limitations: Cross-sectional study with a high proportion of elderly patients, no available information for severity or duration of hypertension and other cardiovascular risk factors, no information for medication use.

Conclusions: These findings suggest that reduced eGFR is associated with cardiac hypertrophy and fibrosis of the left ventricle, cardiac cell enlargement, and cardiac fibrosis.