ALB and Hyponatremia: eGFR (65.2 ± 31.1 vs. 79.7 ± 31.1 ml/min, P < 0.001) and serum albumin (32.9 ± 6.4 vs. 36.8 ± 6.4 g/L, P < 0.001) were lower in COVID-19 patients with hyponatremia.