Objective: To examine the effect of Primary Health Care (PHC) on the association between multimorbidity and emergency service utilization among adults in Brazil.
Methods: This is a cross-sectional, nationwide household-based study using data from the 2019 National Health Survey. Poisson regression was used to assess emergency service utilization among individuals with multimorbidity. The interaction of variables such as Family Health coverage and orientation to PHC in these associations was also evaluated.
Results: The prevalence of multimorbidity was 31.2% (95%CI 30.9-31.5), Family Health coverage was 71.8% (95%CI 71.4-72.0), and low orientation of services toward PHC was 70% (95%CI 69.1-70.9). Emergency service utilization had a prevalence of 2.0% (95%CI 1.9-2.0), being twice as high among individuals with multimorbidity (3.1; 95%CI 2.9-3.3) compared to those without this condition (1.4; 95%CI 1.3-1.5). However, individuals with multimorbidity and Family Health coverage had a 20% lower prevalence of emergency service utilization than those without Family Health coverage (PR 0.8; 95%CI 0.6-0.9). The association between emergency service utilization and multimorbidity was not modified by the evaluation of the service as highly oriented toward PHC (p=0.956).
Conclusion: The study showed that Family Health coverage exerted a positive effect on the association between multimorbidity and emergency service utilization.