Prospective Associations of Pain Intensity and Substance Use in the United States Population: A Cross-Lagged Panel Analysis.

Objective: Pain is associated with increased risk for harmful substance use. Substance use also may increase levels of pain, suggesting that these two factors may reciprocally increase risk. The current study examined the reciprocal association between pain and substance use outcomes (i.e., alcohol, cannabis, and painkillers/sedatives/tranquilizers [PSTs]) longitudinally in a nationally representative cohort of non-incarcerated U.S. citizens.

Method: Adult (≥18 years old) survey data from Waves 2-4 of the Population Assessment of Tobacco and Health (PATH) study were used. The PATH is a nationally representative multiwave cohort survey (Wave 2: October 2014-October 2015, Wave 3: October 2015-October 2016, Wave 4: December 2016-January 2018). Cross-lagged panel models were used to estimate the reciprocal effects of pain intensity and substance use on subsequent changes in both variables. Substance use outcomes were substance use problems and greater-than-weekly use for cannabis and PSTs, total past-month drinks, and alcohol use exceeding moderate drinking guidelines. All models controlled for autoregressive effects and demographic covariates.

Results: Pain intensity showed a positive prospective association with all substance use outcomes. All cannabis and PST use were positively associated with subsequent pain intensity. Alcohol use problems also predicted higher levels of pain intensity. Neither total past-month drinks nor exceeding moderate drinking guidelines predicted subsequent pain intensity.

Conclusions: Pain and substance use show a reciprocal association and may act in a positive feedback loop to worsen both conditions over time in people with a history of use.