Chronic disease diagnoses and health service utilization among people who died from illicit drug intoxication in British Columbia, Canada | BMC Medicine

In this study, the majority of illicit drug toxicity deaths were attributed to a combination of opioids and stimulants, while a smaller proportion of deaths were attributed to opioids or stimulants alone. This suggests that public health officials and health and social service providers need to pay increased attention to the role of stimulants in illicit drug toxicity deaths and provide resources to raise awareness among people who use stimulants ( 18 , 19 , 20 ). ).

Importantly, both opioids and stimulants were considered relevant in the majority of deaths due to illicit drug toxicity. Concomitant use of opioids and stimulants has historically been associated with more frequent and risky drug use patterns and has been linked to premature death (21), which may partially explain the younger age of people in the opioid/stimulant group. Additionally, mental illness was prevalent in these deaths, and people with schizophrenia and delusional disorders were more likely to be in this group. The high rates of diagnosed mental illness in people who have died from illicit drug toxicity and of serious mental illness in people who concurrently use opioids and stimulants are evidence of the high correlation between substance use and the diagnosis of mental disorders (22). As a result, patients and providers are likely to benefit from improved care coordination (23), particularly patients who could access primary care, addiction treatment, and mental health care with fewer barriers (24, 25).

People with mental health and substance use needs have often been excluded from clinical trials for conditions such as ischemic heart disease and psychiatric illness (26). This reduces the applicability of study results to patients with mental illness and substance use needs, and since clinical guidelines are often based on randomized trials, these may not reflect the specific needs of the population, leading to further disparities in medical care.

When considering substances considered relevant to death, both stimulants and opioids were detected in more than 60% of deaths, although the prevalence of service contacts for SUD was lower in this group than in the opioid-only group . These findings highlight potential barriers to accessing services. Studies suggest that evidence-based interventions for OUD, such as: B. treatment with opioid agonists (OAT), are prescribed less frequently in patients with a concurrent stimulant use disorder (27). This suggests that multiple substance use (28), particularly stimulant use, is important in the context of caring for people with OUD and providing pharmacological and psychosocial treatments for substance use disorders, such as: E.g., emergency management for people who use stimulants remains relatively poorly received (29). In addition, OAT is known to protect against mortality, including drug toxicity and cardiovascular deaths (30). There may be fewer OUD diagnoses in this population than expected because the study sample may be individuals who are not engaged in treatment for OUD and are not receiving OAT. Nevertheless, we cannot distinguish whether this is due to a lack of access to services for OUD (ie, OUD present but undiagnosed) or a lack of need for OUD services (ie, no OUD present).

One tenth of the study population consumed stimulants deemed relevant without opioids; This group was older and had a higher rate of cardiovascular comorbidities. While these diagnoses become more common with age, ischemic heart disease and heart failure were overrepresented in people with death from stimulant toxicity, even after adjusting for age. Stimulants such as cocaine and methamphetamine may be associated with overdose risk in people with underlying cardiovascular disease because they can trigger coronary vasospasm, coronary artery plaque rupture, aortic or other artery dissection, or malignant arrhythmia (5, 6). Additionally, long-term use of stimulants can lead to conditions such as high blood pressure and heart failure, especially if there is repeated exposure to stimulants over time (31). Given the strong association between stimulant-related deaths and a history of cardiovascular disease, it may be beneficial for physicians to increase screening and help reduce barriers to treatment for people who use stimulants and suffer from cardiovascular disease, hypertension, and heart failure ( 32). ). While about a quarter of people in the stimulant group were diagnosed with circulatory disease, about 15% of people in the opioid-only group and in the opioid/stimulant group were also diagnosed with circulatory disease, indicating the importance of on Cardiovascular disease is more common in the population of people who use drugs (33).

This study has a number of limitations that need to be taken into account. First, we only included deceased patients, and they may differ systematically from living individuals (e.g., in terms of age, substance use and treatment history, and health profile), which could affect their treatment and prognosis.

Important contextual information required to close cases (e.g., evidence of the substances involved and their relevance to the death) requires significant time and collaboration between coroners, medical examiners, and toxicologists to determine the context of the death (i.e how, when, where and why). ). As noted in the present study, there are known delays between death and closure of cases that have been reported in the context of forensic investigations across Canada (34). This study included only those with completed investigations, and it is possible that patients with more complex investigations or unclear causes of death are underrepresented in this cohort, although analyzes of completed and open cases did not reveal significant differences (Additional file 1: Table S5). ).

When using administrative health data to report chronic disease diagnoses, such as: There are important limitations to consider, such as diagnoses of mental illness and substance use disorders (35). In this study, exposure variables (ie, all chronic disease conditions) were defined based on contact with health services and therefore do not reflect the prevalence of each individual condition, but rather reflect the proportion of the study sample that had contact with health services for each condition.

We also lacked data on how prevalence and frequency of stimulant and opioid use vary by age and chronic disease status. SUD diagnoses were determined using ICD9/10 codes extracted from electronic medical records. For ICD-9 codes, the substance type is indicated at the 4th digit level and for ICD-10 codes at the 3rd digit level. Many electronic records have only a three-digit code, which is likely to be a data quality issue because data entry by third parties rather than physicians can result in loss of information and therefore cannot be determined for which type of SUD the care contact was made. However, unmeasured variables (e.g., unrecorded tobacco use or alcohol use disorder) may have been associated with mortality, and this may be more common in older patients. In addition, it is possible that people in the different drug toxicity death groups differ from one another in ways that we did not measure in this study, but that could contribute to the risk of death due to drug toxicity. For example, previous studies have shown that different risk factors (e.g., solitary use) and protective factors (e.g., access to harm-reduction services, self-regulation) (36) are exercised by and associated with people who use single or polysubstances Opioids vs. stimulants vs. concurrent opioid and stimulant use.

Our administrative health data source contains only a binary indicator of gender, and gender identity data are not available (37). The patients may have recently moved from another province and had no chance of receiving medical care in B.C., or they could have avoided contact with doctors and suffered from undiagnosed medical conditions that were directly attributable to the death but were not recorded and we cannot explain these factors. We cannot explain changes in the composition of the illicit drug supply. Finally, we were unable to capture factors such as consistent supportive primary care or medication adherence, both of which are important in the management of mental and physical health conditions. Additionally, access to medications could be helpful in understanding patterns of health service utilization, but we did not include medication dispensing in our definition of contact services. The relationship between drug administration before death by type of drug toxicity could be the focus of future studies. We only include the diseases listed in the BCCDC CDR. Other diseases (e.g. neurological diseases, gastrointestinal diseases, infectious diseases) were not studied.