. Author manuscript; available in PMC: 2013 May 1.

Published in final edited form as: Sleep Med. 2012 Mar 18;13(5):476–483. doi: 10.1016/j.sleep.2011.12.007

Table 5.

Mediation Analyses: Predictive association between sleep disturbance and poor outcomes after controlling for memory impairment, depressive symptoms, or anxiety symptoms

	COPD Exacerbations^*	Respiratory-Related Emergency Utilization^*	All-Cause Mortality^†
	OR (95% CI) p-value	OR (95% CI) p-value	HR (95% CI) p-value
Controlling for Memory Impairment	10.4 (1.6 – 70) p=0.016	14.3 (1.7 – 118) p=0.013	14.8 (2.2 – 100) p = 0.006

Controlling for Depressive Symptoms	3.4 (0.7 – 15) p = 0.12	8.4 (1.2 – 57) p = 0.03	6.3 (1.2 – 32) p = 0.03

Controlling for Anxiety Symptoms	3.9 (0.99 – 15) p = 0.051	6.9 (1.1 – 45) p = 0.04	8.3 (1.7 – 41) p = 0.009

All models controlled for age, gender, race, marital status, educational attainment, BMI, FEV₁ (absolute), and COPD Severity Score.

Analyses of COPD exacerbations and emergency utilization were multivariable logistic regressions in which the outcome was assessed one year after baseline. Emergency utilization is the combined end-point of either a hospitalization or ED visit.

^†

Analyses of all-cause mortality were multivariable Cox regression analysis in which the outcome was assessed over a median 2.4 years of follow-up.