Longitudinal trajectories of substance use disorder treatment use: A latent class growth analysis using a national cohort in Chile

BACKGROUND AND AIMS

Longitudinal studies have revealed that substance use treatment use is often recurrent among patients; the longitudinal patterns and characteristics of those treatment trajectories have received less attention, particularly in the global south. This study aimed to disentangle heterogeneity in treatment use among adult patients in Chile by identifying distinct treatment trajectory groups and factors associated with them.

DESIGN

National-level registry-based retrospective cohort.

SETTING AND PARTICIPANTS

Adults admitted to publicly funded substance use disorder treatment programs in Chile from November 2009 to November 2010 and followed for 9 years (n = 6266).

MEASUREMENTS

Monthly treatment use; type of treatment; ownership of the treatment center; discharge status; primary substance used; sociodemographic.

FINDINGS

A seven-class treatment trajectory solution was chosen using latent class growth analysis. We identified three trajectory groups that did not recur and had different treatment lengths: Early discontinuation (32%), Less than a year in treatment (19.7%) and Year-long episode, without recurrence (12.3%). We also identified a mixed trajectory group that had a long first treatment or two treatment episodes with a brief time between treatments: Long first treatment, or immediate recurrence (6.3%), and three recurrent treatment trajectory groups: Recurrent and decreasing (14.2%), Early discontinuation with recurrence (9.9%) and Recurrent after long between treatments period (5.7%). Inpatient or outpatient high intensity (vs. outpatient low intensity) at first entry increased the odds of being in the longer one-episode groups compared with the Early discontinuation group. Women had increased odds of belonging to all the recurrent groups. Using cocaine paste (vs. alcohol) as a primary substance decreased the odds of belonging to long one-episode groups.

CONCLUSIONS

In Chile, people in publicly funded treatment for substance use disorder show seven distinct care trajectories: three groups with different treatment lengths and no recurring episodes, a mixed group with a long first treatment or two treatment episodes with a short between-treatment-episodes period and three recurrent treatment groups.

Substance use treatment completion and criminal justice system contact in Chile: A retrospective, linked data cohort study

BACKGROUND AND AIMS

Substance use treatment (SUT) has shown to be effective in reducing self-reported offending; however, the association between SUT completion and criminal justice system (CJS) contact has been underexplored, especially in Latin America. This study aimed to estimate the association between SUT completion status and (1) any subsequent CJS contact and (2) CJS contact leading to imprisonment, at 1, 3 and 5 years post-discharge, in Chile.

DESIGN

Retrospective cohort study using multivariable survival analysis based on linked administrative data from 2010 to 2019.

SETTING

This study took place in Chile, where SUT is available at no cost through Chile's publicly funded health-care, and is provided in outpatient and inpatient modalities in public and private centres.

PARTICIPANTS

A total of 70 854 individuals received their first SUT from 2010 to 2019. They were mainly males (76.3%), and their main substance used at admission was cocaine paste (39.2%).

MEASUREMENTS

SUT completion status included completion, late dropout (≥ 3 months) and early dropout (< 3 months). Outcomes were (1) any CJS contact and (2) CJS contact leading to imprisonment after baseline treatment. We estimated the association between treatment completion and CJS contact through flexible parametric Royston-Parmar models while adjusting for several covariates.

FINDINGS

Those who completed SUT (27.2%) were less likely to have any CJS contact at 5 years post-SUT compared with those who dropped out late [with a gap of -9.5%, 95% confidence interval (CI) = -8.7, -10.3] and early (-11.2%, 95% CI = -10.1, -12.3). Also, those who completed SUT were less likely to have CJS contact leading to imprisonment at 5 years post-SUT compared with those who dropped out late (-2.6%, 95% CI = -2.2, -3.1) and early (-4.0%, 95% CI = -3.3, -4.6). These differences were also observed at 1 and 3 years post-SUT for each outcome.

CONCLUSIONS

In Chile, completion of substance use treatment appears to be associated with lower probabilities of both any criminal justice system contact and contact leading to imprisonment.

Does substance use disorder treatment completion reduce the risk of treatment readmission in Chile?

BACKGROUND

Recovery from substance use disorders (SUD) often entails multiple treatment episodes, which clashes with a context of a treatment system with limited resources and long waiting. Treatment retention and completion have been pointed out as key elements for sustainable achievement; however, most of the evidence generated focuses on opioids and injected substances, which is hardly transferable to the Latin American context.

OBJECTIVES

This study aims to estimate the effect of SUD treatment completion on the risk of being readmitted to a SUD treatment in Chile.

METHODS

We conducted a retrospective analysis on a database of 107,559 treatment episodes from 85,048 adult patients admitted to SUD treatment during 2010-2019 in Chile. We adjusted two separate Prentice Williams and Petersen Gap Time models, to explore the association between treatment completion (vs. non-completion) and up to the third treatment readmission among residential and ambulatory modalities while controlling for time-varying covariates. To examine whether the effect of treatment completion differs between events, we included an interaction term with the stratification variable.

RESULTS

We found that completing the treatment cuts readmission risk for the first event by 17% (Average Hazard Ratio [95% CI] = 0.83 [0.78, 0.88]) and by 14% for the second entry (Average Hazard Ratio [95% CI] = 0.86 [0.78, 0.94]) in ambulatory treatments. We did not find evidence that completing a treatment reduces the readmission risk for residential treatments or third attempts in ambulatory ones.

CONCLUSION

Treatment completion was associated with benefits in cutting readmission risk for the first and second episodes in ambulatory treatments among Chilean adults. It is important to explore different mechanisms than treatment retention for residential treatments.

Effects of 2019's social protests on emergency health services utilization and case severity in Santiago, Chile: a time-series analysis

Background

On October 18th, 2019, protestors gathered across Chile to call for social equity, resulting in widespread civil unrest and violent confrontation with the police. In this study, we quantify the effects of the 2019 Chilean protests on emergency health services utilization and inpatient admission in Santiago.

Methods

We used weekly emergency department (ED) admissions (2015-2019) from three large public hospitals near the focal point of protests in Santiago. The exposure period was from October 18th to December 31st, 2019. The outcomes were the number of weekly consultations and hospitalizations by trauma and respiratory causes and the proportion of hospitalizations among consultants per 1,000. We implemented Bayesian structural time series models to calculate the absolute and relative effects and 95% credible intervals (CrI).

Findings

During the first ten weeks of protests ED consultations declined on average by 14% for trauma (95%CrI: -40·2%, 11·5%) and 30% for respiratory causes (95%CrI: -89·4%, 30·2%), 7% for respiratory hospitalizations (95%CrI: -43·6%, 30·8%); however, none of these three results were statistically distinguishable from the null. Trauma hospitalizations, on the other hand, increased by 15% (95%CrI: 4·0%, 26·4%), and the proportion of hospitalizations per consultations increased by 40% for trauma (95%CrI: 13·1%, 68·0%) and 59% for respiratory causes (95%CrI: 29·4%, 87·9%).

Interpretation

The 2019 Chilean protests affected the use of emergency health services by increasing the trauma hospitalizations and the case hospitalization ratio per 1,000 consultations for trauma and respiratory causes. Crowd-control protocols must be reviewed to prevent the negative effects of civil unrest.

Changes in opioid prescribing after implementation of mandatory registration and proactive reports within California's prescription drug monitoring program

BACKGROUND

In 2016, California updated its prescription drug monitoring program (PDMP), adding two key features: automated proactive reports to prescribers and mandatory registration for prescribers and pharmacists. The effects of these changes on prescribing patterns have not yet been examined. We aimed to evaluate the joint effect of these two PDMP features on county-level prescribing practices in California.

METHODS

Using county-level quarterly data from 2012 to 2017, we estimated the absolute change associated with the implementation of these two PDMP features in seven prescribing indicators in California versus a control group comprising counties in Florida and Washington: opioid prescription rate per 1000 residents; patients' mean daily opioid dosage in milligrams of morphine equivalents[MME]; prescribers' mean daily MME prescribed; prescribers' mean number of opioid prescriptions per day; percentage of patients getting >90 MME/day; percentage of days with overlapping prescriptions for opioids and benzodiazepines; multiple opioid provider episodes per 100,000 residents.

RESULTS

Proactive reports and mandatory registration were associated with a 7.7 MME decrease in patients' mean daily opioid dose (95 %CI: -11.4, -2.9); a 1.8 decrease in the percentage of patients prescribed high-dose opioids (95 %CI: -2.3, -0.9); and a 6.3 MME decrease in prescribers' mean daily dose prescribed (95 %CI: -10.0, -1.3).

CONCLUSIONS

California's implementation of these two PDMP features was associated with decreases in the total quantity of opioid MMEs prescribed, and indicators of patients prescribed high-dose opioids compared to states that had PDMP's without these features. Rates of opioid prescribing and other high-risk prescribing patterns remained unchanged.