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Longitudinal Associations Between Pain and Use of Cigarettes and E-Cigarettes in the Population Assessment of Tobacco and Health (PATH) Study.

INTRODUCTION
Pain has been implicated in the onset and maintenance of nicotine addiction, and there is initial cross-sectional evidence of covariation between pain and use/co-use of cigarettes and e-cigarettes. The goals of the current study were to: (1) test pain severity as a predictor of initiating co-use of cigarettes/e-cigarettes; (2) examine longitudinal associations between pain and use/co-use of cigarette and e-cigarettes; (3) generate the first prevalence rate data regarding cigarette and/or e-cigarette use as a function of pain; and (4) examine gender as a moderator of these associations.


METHODS
Data were drawn from Waves 1-4 of the Population Assessment of Tobacco and Health (PATH) Study (2013-2018).


RESULTS
Among exclusive cigarette smokers at Wave 1 (n = 7,719), pain severity was associated with greater likelihood of and faster trajectory to initiating co-use of cigarettes/e-cigarettes (ps < .05). A significant pain x gender interaction (p < .05) revealed this prospective relationship was stronger among women. Among adult respondents who provided at least three waves of data (n = 24,255), greater Wave 1 pain severity was positively associated with e-cigarette use, cigarette smoking, and co-use of cigarettes/e-cigarettes at Waves 2, 3, and 4 (ps < .001). At Wave 4 (n = 33,822), adults with moderate/severe pain endorsed rates of e-cigarette and cigarette use/co-use almost two times greater versus no/low pain (ps < .001).


CONCLUSIONS
Collectively, these findings provide evidence that pain likely serves as an important candidate risk factor for the initiation and maintenance of cigarette and e-cigarette use.


IMPLICATIONS
This is the first prospective study to show that pain serves as an important risk factor for initiation and maintenance of cigarette and e-cigarette use/co-use over time. Weighted prevalence estimates further demonstrated that individuals with moderate/severe pain endorsed rates of cigarette and e-cigarette use/co-use approximately two times greater compared to those with no/low pain. These findings highlight a subpopulation of nicotine users more susceptible to greater health-care burden, nicotine dependence, and physical impairment. Nicotine users with comorbid pain may benefit from integrated interventions that address pain in the context of cessation.