Hepcidin predicts 5-year mortality after community-acquired pneumonia

Figures & data

Table 1. Baseline characteristics of 267 patients hospitalized with community-acquired pneumonia.

Demographics
Age in years, mean (SD)	64.4 (17.6)
Female gender, n (%)	127 (47.6)
Active smoker, n (%)	65 (24.4)
Nursing home resident, n (%)	4 (1.5)
Comorbid conditions, n (%)	172 (64.4)
Cardiovascular disease^a	74 (27.7)
Chronic obstructive pulmonary disease	60 (22.5)
Immunocompromized^b	48 (18.0)
Autoimmune disease^c	34 (12.7)
Diabetes mellitus	33 (12.4)
Renal disease	32 (12.0)
Neurological disease^d	19 (7.1)
Dementia	15 (5.6)
Liver disease	4 (1.5)
Severity of illness, n (%)
CURB-65 ≥ 3	97 (37.9)
Intensive care unit admission	48 (18.0)
Death within 30 days of admission	10 (3.7)
Established aetiology, n (%)	167 (62.5)
Bacterial	75 (28.1)
Viral	41 (15.4)
Viral-bacterial	51 (19.1)
Unknown	100 (37.5)

CURB-65: Confusion, Urea, Respiratory rate, Blood pressure, Age ≥65 years.

^aHeart failure, coronary heart disease, cerebrovascular disease, peripheral artery disease.

^bPrimary or secondary immunodeficiency, active malignancy, immunosuppressive drugs.

^cRheumatoid arthritis, systemic lupus erythematosus, inflammatory bowel disease, autoimmune hepatitis, Sjogren’s disease, psoriasis.

^dCentral nervous disease, neuromuscular disease.

Figure 1. Kaplan–Meier curves of 5-year overall survival by biomarker values at hospital admission for community-acquired pneumonia, excluding deaths within 30 days from admission. Biomarker cut-offs at median (hepcidin 88 ng/mL, ferritin 386 μg/L, iron 2.9 μmol/L, transferrin 1.65 g/L, transferrin saturation 7.15%, soluble transferrin receptor 1.02 mg/L).

Table 2. 5-Year overall mortality by Cox regression analysis.

	Univariable HR (95% CI), p-value	Multivariable^b HR (95% CI), p-value
Evaluation at admission
Hepcidin	0.32 (0.18–0.57), <0.001	0.46 (0.26–0.84), 0.011
Ferritin	0.55 (0.32–0.95), 0.032	0.90 (0.51–1.58), 0.70
Iron	1.05 (0.62–1.78), 0.86	1.06 (0.62–1.81), 0.84
Transferrin	1.09 (0.64–1.84), 0.76	0.84 (0.49–1.45), 0.53
Transferrin saturation	1.08 (0.63–1.82), 0.79	1.26 (0.73–2.18), 0.40
Soluble transferrin receptor	1.60 (0.94–2.73), 0.086	0.78 (0.45–1.36), 0.38
Anaemia^a	1.65 (0.98–2.76), 0.059	1.60 (0.94–2.72), 0.083
Evaluation at 6-week follow-up
Hepcidin	0.90 (0.52–1.57), 0.71	0.85 (0.49–1.50), 0.59
Ferritin	1.48 (0.84–2.59), 0.17	1.63 (0.89–2.98), 0.11
Iron	0.40 (0.22–0.72), 0.003	0.78 (0.40–1.50), 0.45
Transferrin	0.63 (0.36–1.11), 0.11	0.77 (0.43–1.37), 0.37
Transferrin saturation	0.49 (0.27–0.89), 0.018	0.89 (0.47–1.67), 0.72
Soluble transferrin receptor	2.56 (1.40–4.69), 0.002	1.04 (0.54–1.98), 0.91
Anaemia^a	4.03 (2.33–7.00), <0.001	2.22 (1.24–3.97), 0.008

HR: hazard ratio. Biomarker levels are divided in two categories at median. HR indicates the change of risk from low- to high-level category.

^aCompared to no anaemia.

^bAdjusted for age, sex and number of comorbidities (0, 1, 2 or ≥3).

Bold indicates p < 0.05.