Table 2.

Adjusted associations between deployment duration and respiratory symptoms stratified by capping period among surveyed responders of the Deepwater Horizon oil spill

Pre-Capping (N = 3353)						Post-Capping (N = 1258)
	Deployment Duration	N	Prevalence Ratio	95% CI	ptrend		Deployment Duration	N	Prevalence Ratio	95% CI	ptrend
Coughing (N = 637)	<30 days	146	ref	--		Coughing (N = 242)	<30 days	47	ref	--
	31 to 60 days	291	1.48	1.23 – 1.77			31 to 60 days	157	1.65	1.22 – 2.23	<0.01
	≥60 days	200	2.12	1.75 – 2.56	<0.01		≥60 days	38	2.53	1.74 – 3.68
Shortness of Breath (N = 202)	<30 days	51	ref	--		Shortness of Breath (N = 52)	<30 days	15	ref	--
	31 to 60 days	88	1.31	0.94 – 1.84			31 to 60 days	26	0.86	0.46 – 1.61	0.11
	≥60 days	63	1.91	1.34 – 2.72	<0.01		≥60 days	11	2.32	1.09 – 4.93
Wheezing (N = 130)	<30 days	36	ref	--		Wheezing (N = 36)	<30 days	10	ref	--
	31 to 60 days	55	1.09	0.72 – 1.65			31 to 60 days	15	0.73	0.33 – 1.62
	≥60 days	39	1.61	1.04 – 2.50	0.04		≥60 days	11	3.16	1.38 – 7.24	0.03

Note: Deployments that began after September 30, 2010 were excluded to rule out respiratory symptoms that might have been due to seasonal respiratory infections.

Adjusted for: age and smoking during deployment