Table 3.

Discrete time survival analysis predicting incidence of self-reported chronic obstructive pulmonary disease (COPD) for respondents aged 40 and older, Population Assessment of Tobacco and Health Study (Waves 1-5, 2013-2019)

	Model 1a		Model 2b		Model 3c		Model 4d
Variables	Hazard	95% CI	Hazard	95% CI	Hazard	95% CI	Hazard	95% CI
Time-varying ENDS use	1.98 ***	1.44-2.74	1.70 **	1.21-2.40	1.16	.82-1.65	1.1	.78-1.56
Age (years)e			1.03 ***	1.02-1.03	1.03 ***	1.02-1.04	1.03 ***	1.02-1.04
Sex (Female=1)			1.59 ***	1.34-1.88	1.70 ***	1.42-2.03	1.80 ***	1.51-2.15
Race/Ethnicity
NH White			REF	REF	REF	REF	REF	REF
Hispanic			0.94	.73-1.21	1.06	.82-1.36	1.18	.92-1.52
NH Black			1.21	.99-1.49	1.16	.94-1.44	1.27 *	1.03-1.58
NH Other			0.94	.59-1.49	0.99	.63-1.56	1	.64-1.59
Education
High School or Less			2.19 ***	1.67-2.88	1.83 ***	1.40-2.40	1.72 ***	1.31-2.26
Some College			1.57 **	1.17-2.10	1.40*	1.05-1.88	1.33 *	1.0-1.78
Bachelor Degree or Higher			REF	REF	REF	REF	REF	REF
Uninsured			1.32	.99-1.76	1.18	.88-1.56	1.16	.88-1.55
Baseline Risk Factors
Asthma			2.95 ***	2.26-3.84	2.98 ***	2.29-3.89	3.04 ***	2.32-3.98
Obesity (BMI>30)			1.34 **	1.11-1.63	1.43 ***	1.18-1.73	1.41 **	1.16-1.71
Time-varying second-hand smoke exposuref			1.19 ***	1.15-1.23	1.11 ***	1.07-1.16	1.09 ***	1.04-1.14
Other' combustible tobacco product use					1.26	0.94, 1.68	1.25	0.94-1.65
Time-Varying Smoking Status Indicator
Non-established or never smoking					REF	REF	REF	REF
Former established smoking					1.50 **	1.17-1.94	0.85	.59-1.23
Current established smoking					3.13 ***	2.55, 3.83	1.63 **	1.16-2.27
Log cigarette pack-yearsf							1.79 ***	1.46-2.19

Notes: Person N=9,861; risk N=33,679; Boldface indicates statistical significance

^*p<0.05

^**p<0.01

^***p<0.001

^aENDS exposure

^bsociodemographic variables added

^csmoking status added

^dcigarette pack-years added

^eage mean centered for models

^fvariable rescaled to reflect intervals of 10 hours