Chronic Pain and Health Services Utilization: Is There Overuse of Diagnostic Tests and Inequalities in Nonpharmacologic Treatment Methods Utilization?

Background: Few studies have described patterns and determinants of health services utilization (HSU) in chronic pain (CP) subjects. We aimed to describe these, in particular, regarding medical consultations (MCs), diagnostic tests (DTs), pain medicines (PMs) and nonpharmacologic treatment methods (NTM) utilization. Methods: A cross-sectional nationwide study was conducted in a representative sample of the Portuguese population. The 5094 participants were selected using random digit dialling and were contacted by computer-assisted telephone interviews. Questionnaires included the brief pain inventory and pain disability index. Estimates were adequately weighted for the population. Results: Prevalence of CP and CP with moderate to severe disability was 36.7% and 10.8%, respectively. Most CP subjects were being managed/treated by health professionals (81%) and had high levels of HSU. More than half of them had used imaging DT in the previous 6 months. Main factors associated with HSU were as follows: pain-related disability, intensity, duration, and depressive symptoms for MC utilization; sex, pain-related disability, and duration for PM utilization; and education level and depression diagnosis for NTM utilization. Conclusions: The main drivers behind HSU are pain severity, psychological distress, and socio-economic determinants. An important set of benchmarks are presented regarding HSU in CP subjects, comprising useful tools for public health policy and decision-making. Results presented may suggest possible inequalities in the access to NTM, and interventions to improve access are encouraged. Moreover, possible indirect evidence of imaging DT overuse is presented, and it is recommended that their use in CP subjects should more closely follow existing guidelines.