Improving assessment of subjective memory impairment for detecting Alzheimer's disease: A coordinated analysis in two measurement burst studies

PROJECT SUMMARY The perception of memory problems without objectively identified memory deficit (subjective memory impairment, SMI) is associated with a substantially increased risk of future cognitive decline and Alzheimer’s disease (AD). However, many individuals will endorse SMI but not experience a significant decline in cognition over time. This inconsistency is largely due to current limitations of SMI as an indicator: traditional SMI measures cannot discriminate who will eventually decline, limiting our ability to link the experience of SMI with AD risk. The science examining the SMI‐AD link has relied on measures ask that ask individuals to reflect on their experiences with memory over long periods of time, and to remember what they’ve forgotten. This approach to measurement is susceptible to multiple sources of response bias, such as biased recall and a reliance on self‐schemas about memory abilities (e.g., I’m bad at remembering names) rather than recent experiences with their memory (e.g., I forgot someone’s name yesterday). Traditional measures also don’t differentiate between problems with memory and the consequences of these problems (e.g., health effects of forgetting to take an important medication). In this early stage and new investigator application, we will address these problems by using daily assessments of memory problems (i.e., memory lapses) that occur in the real world to examine cognitive outcomes over time, rather than relying on traditional SMI measures. Daily assessments allow us to separately examine whether the occurrence of memory problems and their consequences serve as separable indicators of future cognitive decline. We will conduct coordinated analyses across two NIA‐funded datasets that repeatedly assessed individuals every six to nine months over a period of three years. At each assessment, participants completed a daily diary that included questions about their memory lapses every day for up to 14 days, as well as ambulatory and lab‐ based tests of memory and other aspects of cognitive performance. Using these datasets, we will examine three aims: 1) test whether the consequences of daily memory lapses are a better predictor of cognitive decline compared with just the occurrence of problems; 2) test whether daily memory lapses and their consequences differ across individuals of different ages and between men and women; 3) test whether the consequences of memory problems are better predictors for individuals who are older, or for men compared with women. Determining what aspects of memory problems, such as their emotional or functional consequences, are better indicators of future cognitive decline would allow us to develop better tools to identify individuals who are at risk for poor cognitive outcomes, including AD. Additionally, if consequences are better predictors for some individuals (e.g., women) compared with others, we will be better prepared to tailor clinical tools to the individuals that are most likely to benefit from early identification.