Estimated Rates of Incident and Persistent Chronic Pain Among US Adults, 2019-2020.

IMPORTANCE

Chronic pain risk and prognosis estimates are needed to inform effective interventions.

OBJECTIVE

To estimate rates of chronic pain and high-impact chronic pain (HICP) incidence and persistence in US adults across demographic groups.

DESIGN, SETTING, AND PARTICIPANTS: This cohort study examined a nationally representative cohort with 1 year of follow-up (mean [SD], 1.3 [0.3] years). Data from the 2019-2020 National Health Interview Survey (NHIS) Longitudinal Cohort were used to assess the incidence rates of chronic pain across demographic groups. The cohort was created using random cluster probability sampling of noninstitutionalized civilian US adults 18 years or older in 2019. Of 21 161 baseline participants in the 2019 NHIS who were randomly chosen for follow-up, 1746 were excluded due to proxy response(s) or lack of contact information, and 334 were deceased or institutionalized. Of the 19 081 remaining, the final analytic sample of 10 415 adults also participated in the 2020 NHIS. Data were analyzed from January 2022 to March 2023.

EXPOSURES

Self-reported baseline sex, race, ethnicity, age, and college attainment.

MAIN OUTCOMES AND MEASURES

Primary outcomes were the incidence rates of chronic pain and HICP, and secondary outcomes were the demographic characteristics and rates across demographic groups. A validated measure of pain status ("In the past 3 months, how often did you have pain? Would you say never, some days, most days, or every day?") yielded 3 discrete categories each year: pain free, nonchronic pain, or chronic pain (pain "most days" or "every day"). Chronic pain present in both survey years was considered persistent; HICP was defined as chronic pain that limited life or work activities on most days or every day. Rates were reported per 1000 person-years (PY) of follow-up, and age standardized based on the 2010 US adult population.

RESULTS

Among 10 415 participants included in the analytic sample, 51.7% (95% CI, 50.3%-53.1%) were female, 54.0% (95% CI, 52.4%-55.5%) were aged 18 to 49 years, 72.6% (95% CI, 70.7%-74.6%) were White, 84.5% (95% CI, 81.6%-85.3%) were non-Hispanic or non-Latino, and 70.5% (95% CI, 69.1%-71.9%) were not college graduates. Among pain-free adults in 2019, incidence rates of chronic pain and HICP in 2020 were 52.4 (95% CI, 44.9-59.9) and 12.0 (95% CI, 8.2-15.8) cases per 1000 PY, respectively. The rates of persistent chronic pain and persistent HICP in 2020 were 462.0 (95% CI, 439.7-484.3) and 361.2 (95% CI, 265.6-456.8) cases per 1000 PY, respectively.

CONCLUSIONS AND RELEVANCE

In this cohort study, the incidence of chronic pain was high compared with other chronic diseases. These results emphasize the high disease burden of chronic pain in the US adult population and the need for early management of pain before it becomes chronic.