Medication non-adherence and self-inflicted violence behaviors among 185,800 patients with schizophrenia in the community: a 12-year cohort study.

BACKGROUND: Despite the importance of medication adherence in treatment effectiveness, little is known about the association between medication non-adherence and self-inflicted violence behaviors. We aimed to assess whether medication non-adherence increased the risk of self-inflicted violence behaviors among schizophrenics in communities (hypothesis 1) and whether the dose-response relationship existed (hypothesis 2). METHODS: This 12-year cohort study in western China recruited 292,667 community-dwelling schizophrenics. The proportion of regular medication (PRM) was calculated by dividing the time of "regular adherence" by the total time of antipsychotic treatment during follow-up period as an indicator of medication adherence. For hypothesis 1, medication adherence was designated as a binary variable with a threshold of 0.8 (PRM); for hypothesis 2, medication adherence was specified as five-category and continuous variables, respectively. Inverse probability weighting and mixed effects Cox proportional hazards models were conducted for confounders control and survival analyses. RESULTS: One hundred eighty-five thousand eight hundred participants were eligible for the final analyses, with a mean age of 47.49 years (SD 14.55 years), of whom 53.6% were female. For hypothesis 1, the medication non-adherence group (PRM < 0.8) had a lower risk of suicide (HR, 0.527, 95% CI, 0.447-0.620), an increased risk of NSSI (HR, 1.229, 95% CI, 1.088-1.388), and non-significant risk of attempted suicide compared with adherence group (PRM ≥ 0.8). For hypothesis 2, the lowest medication adherence (PRM < 0.2) was associated with increased risks of suicide attempt (HR, 1.614, 95% CI, 1.412-1.845), NSSI (HR, 1.873, 95% CI, 1.649-2.126), and a decreased risk of suicide (HR, 0.593, 95% CI, 0.490-0.719). The other non-adherence groups had lower risks for all three self-inflicted violence behaviors. The associations between medication adherence in continuous-variable and three outcomes were consistent with the categorical medication adherence results. CONCLUSIONS: Almost no medication taken as prescribed was associated with an increased risk of suicide attempt and NSSI. However, medication adherence did not appear to prevent completed suicide. Besides, patients with moderate adherence had a lower incidence of suicide attempt and NSSI. These findings highlight the need for a more detailed portrayal of medication adherence and the need to be vigilant for suicide intent in schizophrenics with good medication adherence who may be overlooked previously.

[Dynamic Prediction of Recidivism in Violence in Community-Based Schizophrenia Spectrum Disorder Patients: A Joint Model]. / ç¤¾åŒºç²¾ç¥žåˆ†è£‚ç—‡è°±ç³»éšœç¢æ‚£è€ æš´åŠ›å†çŠ¯åŠ¨æ€é¢„æµ‹ï¼šä¸€ç§è”åˆæ¨¡åž‹.

Objective: To construct a model for predicting recidivism in violence in community-based schizophrenia spectrum disorder patients (SSDP) by adopting a joint modeling method. Methods: Based on the basic data on severe mental illness in Southwest China between January 2017 and June 2018, 4565 community-based SSDP with baseline violent behaviors were selected as the research subjects. We used a growth mixture model (GMM) to identify patterns of medication adherence and social functioning. We then fitted the joint model using a zero-inflated negative binomial regression model and compared it with traditional static models. Finally, we used a 10-fold training-test cross validation framework to evaluate the models' fitting and predictive performance. Results: A total of 157 patients (3.44%) experienced recidivism in violence. Medication compliance and social functioning were fitted into four patterns. In the counting model, age, marital status, educational attainment, economic status, historical types of violence, and medication compliance patterns were predictive factors for the frequency of recidivism of violence (P<0.05). In the zero-inflated model, age, adverse drug reactions, historical types of violence, medication compliance patterns, and social functioning patterns were predictive factors for the recidivism in violence (P<0.05). For the joint model, the average value of Akaike information criterion (AIC) for the train set was 776.5±9.4, the average value of root mean squared error (RMSE) for the testing set was 0.168±0.013, and the average value of mean absolute error (MAE) for the testing set was 0.131±0.018, which were all lower than those of the traditional static models. Conclusion: Joint modeling is an effective statistical strategy for identifying and processing dynamic variables, exhibiting better predictive performance than that of the traditional static models. It can provide new ideas for promoting the construction of comprehensive intervention systems.

[Association Between Medication Compliance and Various Risky Behaviors in Patients With Schizophrenia]. / ç²¾ç¥žåˆ†è£‚ç—‡æ‚£è€ æœè¯ä¾ä»Žæ€§ä¸Žä¸åŒç±»åž‹å±é™©è¡Œä¸ºçš„å ³è”ç ”ç©¶.

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.