Rehabilitation utilization of non-migrant and migrant persons with back pain: A cohort study using different definitions of migrant background.

Background: Medical rehabilitation (MR) by the German Pension Insurance is approved to maintain and to restore work ability and to avoid disability pensions. Studies on the rehabilitation utilization by people with a migration background (PMB) compared to people without a migration background (non-PMB) showed heterogeneous results, which may be partly due to different definitions of migration status. The aim of this paper was to test whether there are differences in utilization of MR between employed PMB and non-PMB with self-reported back pain. Methods: We used data from a large German cohort study that analyzed the effectiveness of MR for individuals with back pain and was conducted between 1st January 2017 and 31st December 2019. Employees aged 45 to 59 years who reported back pain in the last three months completed the baseline questionnaire in 2017. We used four definitions of migration background (MB) to differentiate by first- and second-generation migration, by one- and two-sided migration background, by language, or by nationality. Data on rehabilitation utilization was extracted from administrative records covering the period until the end of 2018. Findings: Data of 6,713 participants were included, and 514 individuals utilized MR during follow-up. Adjusted analyses showed a decreased risk of rehabilitation utilization in people with a first-generation MB (HR = 0·46; 95% CI 0·29; 0·72), people with a two-sided MB (HR = 0·47; 95% CI 0·31; 0·72), people whose native language was not German (HR = 0·52; 95% CI 0·30; 0·91), and people without German nationality (HR = 0·29; 95% CI 0·12; 0·72) when compared to non-PMB. Interpretation: This study showed that employees with a MB reporting back pain had a significantly reduced risk for utilization of rehabilitation services. This underutilization could be observed considering different definitions of MB. Future research on rehabilitation utilization by PMB should consider the impact of different definitions on the results. Funding: The study was funded by the German Research Foundation (grant numbers: BE 5885/2-1; MA 6981/2-1). The German Research Foundation functions as a self-governing institution for the promotion of science and research in Germany.