PTH and nutritional deficiency disease: • Lower ranges of PTH (<300 pg/mL) were correlated with the malnutrition-inflammation score (r = −0.17, p < 0.001), • A moderately low serum PTH in 100–150 pg/mL range was associated with the greatest survival compared to other serum PTH levels (HR 0.52, 95% CI 0.29–0.92, p < 0.001, compared to PTH of 300–600 pg/mL)