GNRI on par with creatinine index in predicting mortality in haemodialysis patients

Both the geriatric nutritional risk index (GNRI) and creatinine (Cr) index can comparably predict mortality risk in older adults receiving haemodialysis, a recent study has shown.

Drawing from the Japan Dialysis Outcomes and Practice Patterns Study, researchers enrolled 3,536 dialysis patients (median age, 66 years; 65.0 percent male). The primary outcome measure of all-cause mortality was measured according to the primary exposure variables of GNRI and Cr index.

Over a median follow-up of 2.2 years, 4,141 all-cause deaths and 151 mortalities from cardiovascular diseases were reported. Nonadjusted Kaplan-Meier curves showed that those with lower GNRI (log-rank p<0.05) and lower Cr index (log-rank p<0.05) had higher incidence rates of all-cause mortalities than comparators with higher index values. A similar trend was reported for cardiovascular deaths.

Cox proportional hazards risk analysis found that a lower GNRI was a significant risk factor for all-cause mortality (Q1 vs Q4: hazard ratio [HR], 2.21, 95 percent confidence interval [CI], 1.61–3.03). This analysis had been adjusted for potential confounders such as age, sex, comorbidities, dialysis vintage and residual kidney function.

Cr index showed the same pattern: lower categories increased the risk of all-cause mortality (Q1 vs Q4: HR, 3.49, 95 percent CI, 2.08–5.85). Both GNRI and the Cr index also had similar c-statistics for the prediction of all-cause mortality (0.749 vs 0.752).

“Because the baseline values that determined a lower GNRI or Cr index category were almost comparable, the GNRI may be more useful than the Cr index for the prediction of mortality in haemodialysis patients because it is a simpler surrogate of nutritional status,” the researchers said.