Background Back pain is the most common musculoskeletal condition worldwide and a leading cause of years lived with disability. It affects people of all ages and is a major cause of activity limitation. Back pain is often a recurrent or long-term condition; however, most previous longitudinal studies have short follow-up periods or limited follow-up points over a long timeframe and, have sampled populations from workplace or clinical settings. We aimed to characterise the long-term profiles of back pain over adulthood and examine whether early life factors are associated with these profiles independent of established adult risk factors.

Methods Data were drawn from a nationally representative British birth cohort, the MRC National Survey of Health and Development. For 3271 participants with at least three assessments of back pain, a longitudinal latent variable analysis was conducted on binary outcomes of back pain at ages 31, 36, 43, 53, 60–64 and 68 using Mplus v 6.12. Derived class posterior probabilities were exported to Stata v14.1 and multinomial logistic regression models with probability weighting were used to examine associations between selected childhood factors (including height, body mass index, serious illness, abdominal pain, emotional and conduct problems, father’s occupational class, mother’s education, parental divorce and parental health) and class membership. Adjustments were made for sex and adult risk factors.

Results Four profiles of back pain were identified: no or occasional pain (54.6% women: 60.8% men), early-adulthood only (16.6%: 15.5%), mid-adulthood onset (18.0%: 15.7%) and persistent (10.8%: 7.9%) pain. No or occasional pain profile was treated as the referent category in subsequent analyses.

In sex-adjusted models, greater height at age 7 was associated with a higher likelihood of early-adulthood only (Relative-Risk Ratio (RRR) per 1 cm increase in height=1.03 [95%CI: 1.01–1.05]) and persistent pain (RRR=1.04 [95%CI: 1.02–1.07]). Other factors associated with increased risk of persistent pain were manual father’s occupational class, severe conduct problems, parental divorce, abdominal pain and average-poor parental health. The latter two factors were also associated with an increased likelihood of mid-adulthood onset pain. In models which included mutual adjustment for other early life factors and adult risk factors, only height at age 7 remained independently associated with early-adulthood only and persistent pain.

Conclusion These findings suggest that a range of factors in early life, most importantly height, are risk factors for long-term experience of back pain across adulthood; therefore interventions that aim to alleviate the burden of back pain may need to start early.