Code from: Risk of dementia and related neurocognitive disorders among autistic and non-autistic older adults: role of established risk factors

Background: Neurocognitive disorders (i.e. dementia) are a leading cause
of cognitive decline and loss of independence among older adults. While
reported rates are higher among autistic adults, it is unclear whether
this disparity persists after accounting for known risk factors.
Objective: We compared neurocognitive disorder risk between autistic and
non-autistic older adults after adjusting for known risk factors and
evaluated whether risk factors moderated this disparity. We replicated our
analyses among subsets of autistic older adults with and without
co-occurring intellectual disability (ID). Design: Retrospective
longitudinal cohort study. Setting: National Medicare Standard Analytical
Files (2013-21). Participants: The sample included 9201 autistic and 18
356 non-autistic older adults aged 65 or older, who were matched on
demographic and clinical characteristics. Methods: Our dependent variable
was time to neurocognitive disorder, defined as years between age 65 or
older and the date of first diagnosis. Results: Autistic older adults had
a 20% higher adjusted risk of neurocognitive disorders than non-autistic
older adults (95% CI = 14%-25%; P < .001). Risk was highest among
autistic adults with co-occurring ID [adjusted subhazard ratio (SHR) =
1.46; 95% CI = 1.36-1.57]. The disparity between cohorts was amplified in
the presence of most known risk factors, notably hypertension (SHR = 2.04;
95% CI = 1.79-2.32), high cholesterol (SHR = 1.60; 95% CI = 1.46-1.75),
depression (SHR = 1.52; 95% CI = 1.42-1.62), and type 2 diabetes (SHR =
1.45; 95% CI = 1.36-1.55). Conclusions: Autistic older adults,
particularly those with ID, face significantly higher risk of
neurocognitive disorders even after adjusting for known risk factors.
These findings emphasize that risk factors may impact the autistic
population differently and highlight the need for early screening and
tailored prevention strategies.