highly significantp < 0.001
Compared with the “Very Low” category, the risk of death increased progressively across other categories, being not significant in the ‘Low’ (RR 1.37; 95% CI 0.99–1.89, p = 0.14), but significant in the “Intermediate” (RR 1.66; 95% CI 1.23–2.23, p = 0.018) and highly significant in the “High” (RR 2.24; 95% CI 1.69–2.97, p < 0.001) after Bonferroni adjustment.