Dementia Care Research and Psychosocial Factors

Down syndrome (DS) is a leading genetic risk factor for Alzheimer's disease (AD). The incidence of clinical symptoms of AD increases dramatically from 8% to 80% between the ages of 40-54 years in persons with DS. The prevention and treatment for AD are well-documented in persons without DS. However, less is known about prevention and treatment for those with DS. The purpose of this systematic review and meta-analysis is to evaluate the efficacy of interventions for the prevention and treatment of AD in persons with DS.

The review was limited to articles with a pharmacological or non-pharmocological program, intervention, or treatment. Studies were included if they were in English, peer-reviewed, included adults ages 18-69 diagnosed with Down syndrome, and published as of Dec 1^st, 2023. Additionally, as this project focused on AD, only articles with dependent variables related to AD, dementia, or AD-related cognitive and behavioral outcomes were included.

A total of 781 records were screened for inclusion. 107 abstracts were then included in a full-text review. 25 articles with 1,417 individuals with DS ages 18-69 met inclusion. Four types of interventions were examined: pharmacological (n = 18), exercise (n = 5), environmental (n = 1), and cognitive training (n = 1). A meta-analysis was used to assess treatment effects on cognitive and behavioral outcomes. Overall, the interventions and treatments significantly improved cognitive and behavior outcomes (t (66) = 4.67, p <0.0001, d =0.29, 95% CI: 0.16-0.40). However, there was high heterogeneity among these effects (I² = 93.8%, 95%CI:92.8-94.7).

AD interventions appear effective for individuals with DS. Pharmacological interventions, specifically donepezil, anti-depressants, EGCG, simvastatin, and nicotine, can improve a broad spectrum of AD outcomes. Exercise and cognitive training are also promising to reduce AD symptoms on this population.