A cohort study examining emergency department visits and hospital admissions among people who use drugs in Ottawa, Canada

Abstract

BackgroundThe health of people who use drugs (PWUD) is characterized by multimorbidity and chronicity of health conditions, necessitating an understanding of their health care utilization. The objective of this study was to evaluate emergency department (ED) visits and hospital admissions among a cohort of PWUD.MethodsWe used a retrospective observational design between 2012 and 2013. The population was a marginalized cohort of PWUD (the PROUD study) for whom survey data was linked (n = 663) to provincial health administrative data housed at the Institute for Clinical Evaluative Sciences. We constructed a 5:1 comparison group matched by age, sex, income quintile, and region. The main outcomes were defined as having two or more ED visits, or one or more hospital admissions, in the year prior to survey completion. We used multivariable logistic regression analyses to identify factors associated with these outcomes.ResultsCompared to the matched cohort, PWUD had higher rates of ED visits (rate ratio [RR] 7.0; 95% confidence interval [95% CI] 6.5–7.6) and hospitalization (RR 7.7; 95% CI 5.9–10.0). After adjustment, factors predicting more ED visits were receiving disability (adjusted odds ratio [AOR] 3.0; 95% CI 1.7–5.5) or income assistance (AOR 2.7; 95% CI 1.5–5.0), injection drug use (AOR 2.1; 95% CI 1.3–3.4), incarceration within 12 months (AOR 1.6; 95% CI 1.1–2.4), mental health comorbidity (AOR 2.1; 95% CI 1.4–3.1), and a suicide attempt within 12 months (AOR 2.1; 95% CI 1.1–3.4). Receiving methadone (AOR 0.5; 95% CI 0.3–0.9) and having a regular family physician (AOR 0.5; 95% CI 0.2–0.9) were associated with lower odds of having more ED visits. Factors associated with more hospital admissions included Aboriginal identity (AOR 2.4; 95% CI 1.4–4.1), receiving disability (AOR 2.4; 95% CI 1.1–5.4), non-injection drug use (opioids and non-opioids) (AOR 2.2; 95% CI 1.1–4.4), comorbid HIV (AOR 2.4; 95% CI 1.2–5.6), mental health comorbidity (AOR 2.4; 95% CI 1.3–4.2), and unstable housing (AOR 1.9; 95% CI 1.0–3.4); there were no protective factors for hospitalization.ConclusionsImproved post-incarceration support, housing services, and access to integrated primary care services including opioid replacement therapy may be effective interventions to decrease acute care use among PWUD, including targeted approaches for people receiving social assistance or with mental health concerns.

Frequency of health‐care utilization by adults who use illicit drugs: a systematic review and meta‐analysis

“…Hospital admission was associated with similar factors: regular or recent injecting , diagnosed hepatitis C , diagnosed HIV , low CD4 count among HIV‐positive participants , female sex , homelessness or unstable housing , alcohol use , polydrug use and mental health problems .…”

“…). Infections and particularly skin and soft‐tissue infections were common causes of ED and in‐patient episodes in study populations in Canada , Norway and Taiwan . All infections, and particularly pneumonias, were important causes of health‐care utilization in HIV‐positive opiate users .…”

“…The proportion of participants who were hospitalized during the past 12 months ranged from 8% to 41% . Studies including relative measures showed frequency of hospital admission two to eight times that of comparison groups not using illicit drugs . Again, studies of people who inject drugs in rural Taiwan and older people who use cannabis in the United States were exceptions, showing similar frequencies of hospital admission to the general population .…”

“…The proportion of participants visiting ED in the past 12 months ranged from 10% to 72% . Studies including relative measures showed frequency of ED utilization of three to 10 times that of comparison groups not using illicit drugs . Exceptions were a study in rural Taiwan, showing that people who inject heroin had a similar rate of ED presentation as the general population , and a study of older people who use cannabis in the United States showing similar odds of ED presentation as those who do not use cannabis .…”

“…ED presentation was consistently associated with regular or recent injecting , sex work, diagnosed hepatitis C , diagnosed HIV , female sex , homelessness or unstable housing , crack cocaine or stimulant use , alcohol use , polydrug use and mental health problems .…”