According to a recent study, cognitive decline is the most important factor in determining how long patients with Alzheimers disease will last after being diagnosed. Thefindings, published in the Journal of Alzheimers Disease, are a first step that could assist health care providers in providing quality planning and monitoring for patients with Alzheimers disease.
C. Munro Cullum, Ph.D., a postdoctoral researcher in clinical neuropsychology at UTSouthwestern, identified seven factors that helped predict life expectancy variability among participants. These factors are the most predictive of how many years of life remain after diagnosis.
Patients with Alzheimers disease are expected to last three to twelve years, but may also be longer in some cases. Families are eager to know what to expect and how to best plan for the future in terms of finances, family caregiving, and how they want to live their lives, according to Dr. Cullum, a neuropsychologist at the Peter ODonnell Jr. Brain Institute. Were attempting to get them better answers.
Performance deficiencies on a brief cognitive screening questionnaire that focuses on orientation were the most significant predictor, accounting for about 20% of the variance in life expectancy. This followed by sex, age, race/ethnicity, neuropsychiatric symptoms, abnormal neurological exam results, and functional impairment ratings.
Dr. Schaffert said that, beyond global cognitive function, patients who were older, non-Hispanic, male, and had a significantly shorter life expectancy.
Patients who died with Alzheimers disease between 2005 and 2015 were identified from clinical records and autopsy reports. Alzheimers disease was confirmed by traditional abnormalities detected in brain autopsy samples, including the presence of abnormal protein aggregation. Life expectancy in the study group varied from one month to 131 months after diagnosis, and the majority were diagnosed on their first visit.
Past studies have focused on only a few of the 21 predictors for life expectancy. In this case, researchers had a complete dataset for 14 variables in this group, the largest to date. Moreover, previous studies have not been autopsy-based, resulting in confounding results with data from other forms of dementia that mimic Alzheimers disease.
Researchers believe that life expectancy prediction is complicated and influenced by many factors. While the cognitive test used in the study was a relatively robust predictor, they plan to follow up by using more sensitive memory and other specific cognitive abilities as predictors and probe how the rate of decline in cognition may track with life expectancy.
This dataset was mostly derived from well-educated white patients who donated their brains to research. Dr. Cullum believes that this effort would be extended to enhance our more diverse patient population.