Trends in In-Hospital Outcomes Among Adults Hospitalized With Exacerbation of Chronic Obstructive Pulmonary Disease

Figures & data

Table 1.  Demographics

	YEAR
	2006		2007		2008			2009			pValue
	(n = 774,497)		(n = 761,919)		(n = 767,326)			(n = 756,823)			Demographics
Demographics											<0.001
Age group (years) (%)
<65	233363	(30.1%)	234967	(30.8%)	236644	(30.8%)		246695	(32.6%)
65–75	231672	(29.9%)	226950	(29.8%)	228893	(29.8%)		227752	(30.1%)
>75	309431	(40.0%)	299968	(39.4%)	301674	(39.3%)		282535	(37.3%)
Sex (%)											<0.001
Male	385902	(49.8%)	378605	(49.7%)	376124	(49.0%)		371865	(49.1%)
Female	388535	(50.2%)	383148	(50.3%)	391054	(51.0%)		384901	(50.9%)
Race (%)											<0.001
White	465109	(60.1%)	446412	(58.6%)	507040	(66.1%)		528176	(69.8%)
Black	53146	(6.9%)	52738	(6.9%)	52398	(6.8%)		59007	(7.8%)
Hispanic	31076	(4.0%)	24667	(3.2%)	26486	(3.5%)		31342	(4.1%)
Annual Income (%)											<0.001
$1–24,999	246189	(31.8%)	253896	(33.3%)	244324	(31.8%)		243501	(32.2%)
$25,000–34,999	208523	(26.9%)	207665	(27.3%)	227544	(29.7%)		215821	(28.5%)
$35,000–44,999	175169	(22.6%)	164346	(21.6%)	160695	(20.9%)		165010	(21.8%)
$45,000 or more	126961	(16.4%)	117318	(15.4%)	118212	(15.4%)		114037	(15.1%)
Medical History
Diabetes Mellitus	205947	(26.6%)	214441	(28.1%)	219339	(28.6%)		224234	(29.6%)		<0.001
Congestive heart failure	258652	(33.4%)	248933	(32.7%)	234195	(30.5%)		234713	(31.0%)		<0.001
Valvular heart disease	74193	(9.6%)	70677	(9.3%)	60423	(7.9%)		59971	(7.9%)		<0.001
Arrhythmia	214970	(27.8%)	213207	(28.0%)	208871	(27.2%)		210080	(27.8%)		<0.001
Myocardial infarction
Current	51936	(6.7%)	47910	(6.3%)	45670	(6.0%)		44216	(5.8%)		<0.001
Prior	52904	(6.8%)	54170	(7.1%)	56532	(7.4%)		55240	(7.3%)		<0.001
Cerebrovascular disease	32990	(4.3%)	32369	(4.2%)	32811	(4.3%)		32039	(4.2%)		0.568
$45,000 or more	126961	(16.4%)	117318	(15.4%)	118212	(15.4%)		114037	(15.1%)

Figure 1.  All-cause in-hospital mortality rates in patients hospitalized with COPD exacerbation.

Figure 2.  Rates of (A) mechanical ventilation and (B) noninvasive positive pressure ventilation in patients hospitalized with COPD exacerbation.

Figure 3.  Average hospital length of stay in days in patients hospitalized with COPD exacerbation.

Table 2.  Multivariate logistic regression models

	Odds Ratio	95% Confidence Interval	p-Value
Mortality^1
Discharge Year 2006 (referent)	1.00	–	–
Discharge Year 2007 (vs. 2006)	0.95	0.94–0.97	<0.001
Discharge Year 2008 (vs. 2006)	0.92	0.90–0.93	<0.001
Discharge Year 2009 (vs. 2006)	0.84	0.83–0.86	<0.001
Mechanical Ventilation^2
Discharge Year 2006 (referent)	1.00	–	–
Discharge Year 2007 (vs. 2006)	1.01	0.99–1.02	0.431
Discharge Year 2008 (vs. 2006)	0.95	0.94–0.96	<0.001
Discharge Year 2009 (vs. 2006)	0.95	0.94–0.97	<0.001
Non-invasive Positive Pressure Ventilation^3
Discharge Year 2006 (referent)	1.00	–	–
Discharge Year 2007 (vs. 2006)	1.30	1.27–1.32	<0.001
Discharge Year 2008 (vs. 2006)	1.48	1.45–1.51	<0.001
Discharge Year 2009 (vs. 2006)	1.57	1.55–1.60	<0.001

1Model includes hospital discharge year, age group, gender, race, Hispanic ethnicity, annual income, hypertension, diabetes mellitus, renal failure, congestive heart failure, valvular heart disease, arrhythmia, current myocardial infarction, prior myocardial infarction, cerebrovascular disease, mechanical ventilation, and non-invasive positive pressure ventilation.

2Model includes hospital discharge year, age group, gender, race, Hispanic ethnicity, annual income, hypertension, diabetes mellitus, renal failure, congestive heart failure, valvular heart disease, arrhythmia, current myocardial infarction, prior myocardial infarction, and cerebrovascular disease.

3Model includes hospital discharge year, age group, gender, race, Hispanic ethnicity, annual income, hypertension, diabetes mellitus, renal failure, congestive heart failure, valvular heart disease, arrhythmia, current myocardial infarction, prior myocardial infarction, and cerebrovascular disease.

Table 3.  Multivariate linear regression of hospital length of stay

	Beta Coefficient	Standard Error	p-Value
Hospital Length of Stay
Discharge Year 2006 (referent)	0.000	–	–
Discharge Year 2007 (vs. 2006)	–0.074	0.010	<0.001
Discharge Year 2008 (vs. 2006)	–0.307	0.010	<0.001
Discharge Year 2009 (vs. 2006)	–0.447	0.011	<0.001

*Model includes hospital discharge year, age group, gender, race, Hispanic ethnicity, annual income, hypertension, diabetes mellitus, renal failure, congestive heart failure, valvular heart disease, arrhythmia, current myocardial infarction, prior myocardial infarction, cerebrovascular disease, mechanical ventilation, and non-invasive positive pressure ventilation.

Table 4.  Multivariate logistic regression models for in-hospital mortality for each discharge year

	2006			2007			2008			2009
	OR	95% CI	P	OR	95% CI	P	OR	95% CI	P	OR	95% CI	P
Age < 65 years [referent]	1.00	–	–	1.00	–	–	1.00	–	–	1.00	–	–
Age 65–75 years	1.66	1.60–1.71	<0.001	1.68	1.62–1.74	<0.001	1.76	1.69–1.82	<0.001	1.79	1.72–1.86	<0.001
Age > 75 years	2.66	2.57–2.74	<0.001	2.80	2.71–2.89	<0.001	3.07	2.97–3.18	<0.001	3.20	3.09–3.32	<0.001
Male gender	1.15	1.12–1.17	<0.001	1.12	1.10–1.55	<0.001	1.17	1.14–1.19	<0.001	1.15	1.12–1.17	<0.001
White race [referent]	1.00	–	–	1.00	–	–	1.00	–	–	1.00	–	–
Black race	0.88	0.84–0.92	<0.001	0.90	0.85–0.94	<0.001	0.84	0.80–0.89	<0.001	0.79	0.75–0.83	<0.001
Hispanic race	1.06	1.01–1.12	0.030	0.96	0.90–1.03	0.321	0.98	0.91–1.04	0.534	0.98	0.92–1.05	0.700
Annual Income < $25,000	1.00	–	–	1.00	–	–	1.00	–	–	1.00	–	–
Annual Income $25,000–$34,999	1.01	0.98–1.04	0.527	0.99	0.96–1.20	0.805	0.93	0.91–0.96	<0.001	0.96	0.93–1.00	0.063
Annual Income $35,000–$44,999	0.98	0.95–1.01	0.282	1.02	0.98–1.05	0.208	0.93	0.95–0.96	<0.001	0.98	0.94–1.01	0.310
Annual Income $45,000 or more	1.03	0.99–1.06	0.850	1.03	1.00–1.05	0.036	0.99	0.95–1.02	0.649	0.98	0.94–1.02	0.453
Hypertension	0.60	0.53–0.67	<0.001	0.52	0.45–0.59	<0.001	0.62	0.55–0.71	<0.001	0.61	0.53–0.69	<0.001
Diabetes mellitus	0.70	0.68–0.72	<0.001	0.69	0.67–0.71	<0.001	0.74	0.72–0.76	<0.001	0.74	0.72–0.77	<0.001
Renal failure	1.48	1.43–1.52	<0.001	1.76	1.67–1.85	<0.001	1.79	1.69–1.89	<0.001	1.86	1.75–1.97	<0.001
Congestive heart failure	1.26	1.23–1.29	<0.001	1.19	1.16–1.22	<0.001	1.15	1.12–1.89	<0.001	1.12	1.09–1.15	<0.001
Valvular heart disease	0.78	0.74–0.80	<0.001	0.79	0.76–0.82	<0.001	0.73	0.70–0.77	<0.001	0.76	0.72–0.80	<0.001
Arrhythmia	1.58	1.54–1.62	<0.001	1.62	1.59–1.66	<0.001	1.50	1.46–1.54	<0.001	1.49	1.46–1.53	<0.001
Current myocardial infarction	1.47	1.42–1.52	<0.001	1.54	1.49–1.60	<0.001	1.00	1.00–1.00	0.989	1.69	1.62–1.75	<0.001
Prior myocardial infarction	0.61	0.58–0.64	<0.001	0.63	0.59–0.66	<0.001	0.71	0.67–0.75	<0.001	0.68	0.64–0.72	<0.001
Mechanical ventilation	11.03	10.75–11.31	<0.001	11.43	11.13–11.74	<0.001	12.76	12.41–13.11	<0.001	13.44	13.06–13.82	<0.001
NIPPV	2.43	2.31–2.55	<0.001	2.55	2.44–2.67	<0.001	2.58	2.47–2.70	<0.001	2.88	2.76–3.01	<0.001

OR: odds ratio, CI: Confidence Interval, NIPPV: non–invasive positive pressure ventilation.