Background: Hypertension combined with CKD is on the rise in middle-aged and elderly people. However, the association of early subclinical decline in kidney function with long-term mortality in these populations remains unclear. In this study, we developed a novel method for evaluating kidney function in middle-aged and elderly patients with hypertension and predicting their long-term survival outcomes based on the thresholds of estimated glomerular filtration rate (eGFR).
Methods: We constructed a retrospective cohort study with a sample of 350 patients and used time-dependent COX regression analysis to analyze the effect of eGFR threshold changes over time on survival outcomes. Patients were divided into three subgroups based on eGFR values and age (eGFRc=1, eGFRc=2 eGFRc=3). We analyzed the potential prognostic clinicopathological factors via univariate and multivariate Cox regression. A prediction model combined the prognostic clinicopathological factors with age-related eGFRc grouping was builded.
Results: The lower eGFR groups had significantly lower rates of survival (hazard ratio [HR] eGFRc=2 = 2.407, 95% confidence interval [CI]: 1.663–3.484, P = 0.000; HR eGFRc=3 = 7.081, 95% CI: 4.925–10.179, P = 0.000). The prediction model combined urinary albumintocreatinine ratio (ACR), Diabetes mellitus (DM), stroke, systolic blood pressure (SBP), diastolic blood pressure (DBP), with age-related eGFRc grouping significantly predicted the long-term survival of patients with hypertension (AUC = 0.827, P = 0.0105).
Conclusions:The model above can be utilized for determining the thresholds of estimated renal function and assessing long-term survival in middle-aged and elderly patients with hypertension.