Testing the association between shoulder pain prevalence and occupational, physical activity, and mental health factors in two generations of Australian adults.

Background: Shoulder pain is common among the adult population, but it appears to reduce in prevalence around retirement age. Associations between shoulder pain and work-place exposures, physical activity, or mental health status are unclear and may change with age. This study aimed to determine the prevalence of self-reported shoulder pain in Australian adults across two generations and test the association with occupational factors, physical activity, and mental health.

Methods: In this cross-sectional study we used data from a longitudinal Australian pregnancy cohort (the Raine Study). We analysed data from the children (Gen2) at the 22-year follow-up (N = 1128) and parents (Gen1) at the 26-year follow-up (N = 1098). Data were collected on self-reported shoulder pain, occupational factors (employment status and work description), physical activity, and mental health at the respective follow-ups. Prevalence rates were provided as percentages with 95% confidence intervals. Univariate analysis for group comparisons included chi squared for categorical comparisons. The association of predictor variables and shoulder pain was assessed using logistical regression.

Results: In Gen1 31.4% of adults aged 40-80 reported the presence of shoulder pain in the last month, with no significant difference between females and males. Gen1 participants younger than 65 reported more shoulder pain (OR[95%CI] = 1.80 [1.04-3.09]). Gen2 females (14.7%) reported shoulder pain in either shoulder more frequently than males (7.7%) and bilateral shoulder pain (8.0%) more frequently than males (1.9%). Gen1 had increased odds of reporting shoulder pain if their work was "physical or heavy manual" compared to "sedentary" (OR [95% CI] = 1.659 [1.185-2.323]) and when categorised with depression (OR [95% CI] = 1.940 [1.386-2.715]) or anxiety (OR [95% CI] = 1.977 [1.368-2.857]). Gen2 participants with depression (OR [95% CI] = 2.356 [1.620-3.427]) or anxiety (OR [95% CI] = 2.003 [1.359-2.952]) reported more shoulder pain.

Conclusion: Overall, shoulder pain was more prevalent in young females than males and was more prevalent in those under the age of 65. Cross-sectional associations were established between some occupational factors in older adults and depression in all adults, and shoulder pain.