ICES Toronto Canada

INTRODUCTION In 2013, illegally manufactured fentanyl began to emerge within the unregulated drug supply across Canada and the United States (US), quickly becoming a major driver of the current drug toxicity crisis [1, 2]. In the United States, there was a 100.7% increase in deaths involving synthetic opioids (predominantly fentanyl) between January 2020 and 2023 [3]. Similar trends have been observed in Canada, where over 80% of opioid-related deaths in 2023 were attributed to fentanyl [4].

1 Background Intellectual and developmental disabilities (IDD) affect approximately 1%–3% of the population [1], encompassing conditions commonly characterized by limitations in intellectual functioning, adaptive behavior, and social skills [2]. Individuals with IDD face significant health inequities [3, 4], including a greater risk of developing cancer at younger ages compared to those without these disabilities [5-7].

Limited studies have investigated the incidence and prevalence of dementia in persons with Non-DS IDD. Among the existing studies, there has been conflicting results leading to no general consensus for this topic. This population-based study retrospectively identified persons with and without IDD using ICD-9 and -10 to compare the cumulative incidence and period prevalence of dementia.