Senior Director Certara Ltd., UK London, United Kingdom
Background: Alzheimer’s disease (AD) is an irreversible, progressive, neurodegenerative disease that affects memory, cognition, and function, with mild cognitive impairment (MCI) considered to be an important prodrome for AD. There were an estimated 6.2 million people aged 65 years or older living with AD in the United States (US) in 2021. AD causes considerable disability and is eventually fatal. Individuals with AD typically have high levels of dependency and as a result, the public health impact of this condition is considerable. The societal costs of AD and MCI, including reductions in quality of life (QoL) among both patients and their caregivers, are less well-documented.
Objectives: This study aimed to measure QoL among patients clinically diagnosed with MCI or mild, moderate, or severe AD in the US, and to assess the care-related QoL of their caregivers.
Methods: A survey was conducted among patient-caregiver pairs living in the US. Patients had to be diagnosed with MCI or AD by their treating physician at least 3 months prior to the survey. The survey included the Dementia Quality of Life Proxy Questionnaire (DEMQOL-Proxy) to assess the health-related QoL of dementia patients (range: 31-124, higher scores = better QoL). The CarerQoL instrument was administered to measure care-related QoL of caregivers, and US-specific tariffs were applied to obtain an overall CarerQoL score (higher scores = better QoL). The level of caregiving needs was assessed using the Dependence Scale (DS) (range: 0-15, higher scores = more dependence).
Results: A total of 100 patient-caregiver pairs were analyzed for patients with MCI (n=27), and mild (n=27), moderate (n=25), or severe (n=21) AD. Among patients with MCI and AD, 21% and 47% were aged >75 years, and 59% and 48% were female, respectively. Among all caregivers, 38% were aged < 50 years and 65% female. Health-related QoL (DEMQOL-Proxy scores) significantly decreased with increasing disease severity of AD patients (p < 0.001): 93.3 (±8.6) for MCI, and 85.3 (±12.2), 91.2 (±11.7) and 65.2 (±19.2) for mild, moderate, and severe AD, respectively. Care-related QoL (CarerQoL scores) showed no significant differences across disease severity categories: 80.8 (±9.1) for MCI, and 74.2 (±12.0), 77.7 (±12.8) and 78.9 (±11.9) for mild, moderate, and severe AD, respectively. A statistically significant increase in dependence was observed with increasing severity (p < 0.001): overall DS scores were 6.7 (±2.9) for MCI, and 6.4 (±2.6), 7.4 (±3.5) and 11.8 (±2.7) for mild, moderate, and severe AD, respectively.
Conclusions: AD severity has significantly negative impact on patient QoL and independence. No significant variability in caregiver QoL is observed across patient disease severity categories.
