Six underlying health conditions strongly influence mortality based on pneumonia severity in an ageing population of Japan: a prospective cohort study

Table 2 Risk factors for 30-day mortality

	30-day mortality
	univariate analysis		multivariate analysis^b
	OR	95% CI	AOR	95% CI
Underlying health conditions
Age group (years old)
≤ 64	(1.00)		(1.00)
65–74	2.46	1.27–4.74	1.61	0.80–3.26
75–84	2.49	1.37–4.53	1.37	0.70–2.69
≥ 85	3.98	2.21–7.16	2.15	1.08–4.28
HCAP criteria
Hospitalization ≥2 days within 90 days	2.96	2.03–4.31	2.21	1.36–3.60
Nursing home resident	2.16	1.44–3.24	1.53	0.92–2.56
Chronic dialysis within 30 days	2.48	0.92–6.66
Home care ^a	7.00	2.69–18.23	5.84	2.28–14.99
Male gender	1.84	1.26–2.69	1.78	1.16–2.75
Comorbid illnesses
Congestive heart failure	1.53	0.97–2.40
Liver disease	1.75	0.93–3.29	1.77	0.87–3.61
Renal disease	1.54	0.92–2.61
Neoplastic disease	2.18	1.49–3.18	1.82	1.17–2.85
Chronic lung disease	1.28	0.86–1.90
Diabetes mellitus	1.22	0.80–1.86
Dementia	1.69	1.09–2.63
Risk factors for aspiration
Witnessed aspiration	1.72	1.16–2.55
Chronic impaired conscious level	2.71	1.28–4.98	1.75	0.81–3.76
Chronic neurologic disorders	0.80	0.37–1.76
Foreign bodies interfering with swallowing	1.28	0.29–5.56	0.43	0.10–1.87
Bed-ridden state	2.49	1.53–4.06
Body mass index
< 18.5	2.63	1.72–4.04	1.99	1.25–3.16
18.5–24.9	(1.00)		(1.00)
≥ 25	0.79	0.36–1.70	1.10	0.77–3.99
CURB score
0	(1.00)		(1.00)
1	2.38	1.30–4.33	1.87	1.01–3.46
2	5.04	2.74–9.25	3.65	1.95–6.82
3	7.45	3.71–14.99	4.90	2.22–10.81
4	35.78	9.88–129.59	29.14	6.07–139.74

OR odds ratio, CI confidence interval, AOR adjusted odds ratio, HCAP healthcare-associated pneumonia, CURB Confusion, blood Urea nitrogen > 7 mmol/L, Respiratory rate > 30 per minute, and Blood pressure < 90 mmHg in systole or ≤ 60 mmHg in diastole
^aHome care: home infusion therapy or wound care
^bVariables after the variables with p > 0.2 had been removed by the backward stepwise method

ISSN: 1471-2466