A clinical nomogram for the prediction of early mortality in elderly patients initiating dialysis for end-stage renal disease

Abstract

Abstract Background The number of elderly patients (> 80 years of age) with end-stage renal disease is rapidly increasing. The initiation of dialysis extends the duration of survival; however, the rate of early mortality, that which occurs within the first few months after the initiation of dialysis, is reportedly higher than the rate of late mortality. Methods We retrospectively studied a cohort of 300 patients, aged 80 years or older, in whom dialysis was initiated between January 1, 2010, and December 31, 2017, at TOHO Hospital (Gunma, Japan). The rate of early mortality was assessed using the Kaplan-Meier method, and the equivalence of survival curves was tested using log-rank tests. The univariate and multivariate analyses were performed using the Cox proportional hazards model. To evaluate nomogram performance, we assessed both the discrimination and calibration of these models. Two hundred bootstrap resamples were used for internal validation of the accuracy estimates to reduce overfit bias and to determine 95% confidence intervals. Results The nomogram was built using the following nine predictors: serum albumin grams per deciliter (hazard ratio [HR] 0.63, p < 0.001), congestive heart failure (HR 1.81, p = 0.004), chronic obstructive pulmonary disease (HR 2.47, p = 0.014), peripheral vascular disease (HR 2.03, p = 0.019), hemiplegia (HR 2.06, p = 0.001), malignant tumors (no metastasis; HR 2.00, p < 0.001), metastatic malignant tumors (HR 4.67, p = 0.006), cardiovascular disease (HR 1.59, p = 0.002), bone fractures due to falls within 1 year (HR 1.85, p = 0.011), and Karnofsky Performance Status (HR 0.98, p < 0.001). Conclusions We developed and validated a nomogram that predicts early mortality in elderly patients at the initiation of dialysis for end-stage renal disease. The nomogram may help nephrologists make a shared decision with patients and families regarding the initiation of dialysis.