Quality of Life in Mild Cognitive Impairment and Mild Dementia Associated with Alzheimer’s Disease: A Systematic Review

Mild cognitive impairment (MCI) and Alzheimer's disease (AD) have a profound impact on patients' quality of life (QoL), with progressive declines occurring as the disease advances. This systematic review aims to summarize the published evidence on patient-reported outcomes (PROs) in individuals with MCI due to AD and mild AD dementia. Comprehensive searches were conducted across five major databases to identify studies reporting on utility values, disutilities, and QoL measures in these patient populations. A total of 23 studies were included that utilized various QoL assessment tools, including EQ-5D (n = 14), SF-36/SF-12 (n = 4), and QOL-AD (n = 11). Reported EQ-5D scores ranged from 0.81 to 0.92 for patients with MCI and from 0.67 to 0.85 for those with mild AD, indicating a noticeable decline in QoL as the disease progresses. QOL-AD scores ranged from 33.8 to 42.5 for MCI and from 32.4 to 38.1 for mild AD, equally reflecting the greater impairment in QoL with disease advancement. Interventions were generally associated with smaller declines in PROs compared to placebo, suggesting a positive impact of treatment in mitigating QoL deterioration. The findings underscore the significant QoL differences between MCI and mild AD, emphasizing the potential benefit of early intervention to preserve QoL and delay disease progression. This review highlights the importance of continued research to better understand QoL in patients with MCI and mild AD dementia, particularly in terms of capturing comprehensive patient-reported outcomes and evaluating the effectiveness of interventions over time. These findings can contribute to a more informed approach in clinical practice and support decision-making in the management of early-stage AD.