Co-occurrence of mental distress and insomnia associates with more severe musculoskeletal pain – Northern Finland Birth Cohort 1966 study

Objective

This cross-sectional study demonstrates the differences in the dimensions of musculoskeletal (MSK) pain between participants with mental distress and/or insomnia among general population with MSK pain within the past 12 months.

Methods

Participants of Northern Finland Birth Cohort 1966 (NFBC1966) were studied (n = 4316). They were divided into groups based on their mental distress and insomnia status (co-occurring mental distress and insomnia [CMI], isolated mental distress [M] and insomnia [I], and absence of both [AMI]). The AMI group was used as a reference for the main analyses. The dimensions of MSK pain included frequency, bothersomeness (Numerical Rating Scale [NRS] 0–10), intensity of pain (NRS), and number of pain sites (1–8). Multinomial and general linear regression analyses were used to study the associations, and adjustments were made for sex, education, number of somatic diseases, and physical activity.

Results

The CMI group was associated with more severe pain in every dimension when contrasted to all other groups (daily pain adjusted OR 5.08, 95 % CI 3.43–7.51; bothersomeness adjusted β 1.7, 95 % CI 1.5–2.0; intensity adjusted β 1.4, 95 % CI 1.2–1.7; number of pain sites adjusted β 1.2, 95 % CI 1.0–1.4). Compared to AMI, I and M groups also had relationships with all pain dimensions, but with lower magnitude compared to the CMI group.

Conclusions

The results suggest that insomnia and mental distress co-exist with more severe MSK pain, and when co-occurring, MSK pain severity tends to increase. Therefore, contemplating insomnia and mental distress are important to consider when comprehensively evaluating MSK pain symptoms.