Statistical analysis
Distributions of baseline characteristics were compared among five eGFR
groups, including sex, age, BMI, smoking, comorbidity, clinical
characteristics, medication use prior to admission, and the 1-month, and
1-year mortality rates. Data of continuous variables were expressed as
median and 25th percentile to 75th percentile and examined using the
Kruskal-Wallis test for continuous variables that were not normally
distributed. Categorical variables were expressed as frequencies and
examined using the Chi-square test.
The cumulative incidence curves of mortality were computed for the 5
subgroups of eGFR levels by the Kaplan–Meier method and tested using
the log-rank test. The 1-month and 1-year mortality rates (per 1000
person-days) after intracerebral hemorrhagic were calculated by the eGFR
levels. We further used the Cox proportional hazards regression analysis
to estimate the hazard ratio (HR) of mortality and 95% confidence
interval (CI) associated with eGFR levels at admission for patients with
intracerebral hemorrhage, using patients with eGFR ≥ 90mL/min/1.73
m2 as references. We also used the receiver operating
characteristic (ROC) curve to assess the predictive performance of eGFR
levels with regard to one-month mortality and one-year mortality after
intracerebral hemorrhage. All statistical analyses were performed using
SAS statistical software, version 9.4 (SAS Institute Inc., Cary, NC).
Statistical significance was defined using two‐tailed tests
(P < 0.05).