Associations and synergistic effects for psychological distress and chronic back pain on the utilization of different levels of ambulatory health care: a cross-sectional study from Austria

The aim of this analysis was to assess the impact of chronic back pain and psychological distress on the utilization of primary and secondary levels of care in the ambulatory health care sector in Austria - a country without a gatekeeping system. Additionally, we aimed to determine if the joint effect of chronic back pain and psychological distress was higher than the impact of the sum of the two single conditions. The database used for this analysis was the Austrian Health Interview Survey, with data from 15,474 individuals. Statistical methods used were descriptive tests, regression models and the calculation of synergistic effects. Both chronic back pain and psychological distress had a positive association with the utilization of the primary (OR for chronic back pain 1.53 and psychological distress 1.33) and secondary (OR for chronic back pain 1.32 and psychological distress 1.24) levels of the health care sector. In the fully adjusted model, the synergistic effect of chronic back pain and psychological distress was significant for the secondary level of care (S 1.99, PAF 0.20), but not for the primary level of care (S 1.16, PAF 0.07). Synergistic effects and associations for chronic back pain and psychological distress on the utilization of both the primary and secondary levels of the ambulatory health care sector were observed, particularly for the secondary level of care. Our results demonstrate the utilization of health care services settings by individuals with these conditions, and offer opportunities to consider reorganization and structuring of the Austrian health care system