Objective To investigate the status of medication adherence and various types of risky behaviors of schizophrenia patients in a certain area of western China and to explore accordingly the correlation between the two.
Methods A total of 292 667 patients with schizophrenia were enrolled in a follow-up survey between 2006 and 2018. In addition, based on the outcome-wide analysis strategy, a multivariate Cox proportional risk regression model was used to estimate and compare the impact of medication adherence on different types of risky behaviors in schizophrenia patients.
Results In this 13-year prospective cohort, 65 175 patients (31.4%) showed good medication adherence, while 142 394 patients (68.6%) showed poor medication adherence. The incidence rates of various risky behaviors during the follow-up period were as follows, minor nuisances, 12.25%, violation of the Law of the People's Republic of China on Penalties for Administration of Public Security (APS law), 3.82%, violation of criminal law, 0.94%, suicide completed, 0.28%, self-harm, 1.42%, and attempted suicide, 0.82%. Schizophrenia patients who had poor medication adherence had higher risks of committing violence against others and self-inflicted injury compared to patients with good medication adherence did, with the associated effects being minor nuisances (hazard ratio HR=1.31, 95% confidence interval CI: 1.27-1.35), violation of APS law (HR=1.47, 95% CI: 1.38-1.56), violation of criminal law (HR=1.17, 95% CI: 1.05-1.31), and self-harm (HR=1.43, 95% CI: 1.32-1.56), respectively, while the risk of suicide completed is lower in schizophrenia patients with poor medication adherence than that in patients with good medication adherence (HR=0.56, 95% CI: 0.47-0.66). There was no statistically significant association between attempted suicide and medication adherence.
Conclusion There are variations in the direction and strength of the association between medication adherence and different types of risky behaviors and further research is needed to elucidate the mechanisms of the association.