Test predicts transition from normal to cognitive impairment

Longitudinal data showed that the Stages of Objective Memory Impairment (SOMI) system predicted the transition from normal cognition to episodic symptomatic cognitive impairment.

Cognitively normal older adults (SOMI-2) with scores on memory tests reflecting moderate retrieval impairment compared to older adults with intact memory (SOMI-0) at an average of approximately 6 years of follow-up. were twice as likely to progress to occasional cognitive impairment. According to Dr. Ellen Glover of Albert Einstein College of Medicine in New York City and co-authors.

Participants with memory impairment (SOMI-3 or SOMI-4) were three times more likely to progress, researchers reported. neurologyAfter adjusting for all biomarkers, SOMI stage remained an independent predictor of incident cognitive impairment.

“There is increasing evidence that some people with thinking and memory problems may actually have very subtle signs of early cognitive impairment,” Glover said in a statement.

“In our study, a highly sensitive and brief memory test predicted the risk of developing cognitive impairment in people who were thought to have normal cognition,” she added. “Our results support the use of the SOMI system to identify people most likely to develop cognitive impairment.”

Previous studies have used the SOMI results to Presence of Alzheimer’s disease pathology in people without cognitive impairment in anti-amyloid therapy in clinical trials for asymptomatic Alzheimer’s disease (A4).

SOMI is based on the Free and Cued Selective Reminding Test (FCSRT). The test begins with a learning phase, on each of which he is shown four cards with four items on them and is asked to identify which items belong to a particular category (e.g. apples belong to the category of fruits). increase). Participants are then asked to recall the item. If they are stuck, they are given categorical clues to prompt them.

“The FCSRT provides measures of memory retrieval (free recall) and memory preservation (complete recall),” write Grober and co-authors. “The free recall score predicts the development of mild cognitive impairment and the development of dementia, particularly dementia due to Alzheimer’s disease, and often outperforms other cognitive tests.”

The SOMI system maps free recall and total recall scores to stages. Free and total recall are normal in SOMI-0. SOMI-1 and SOMI-2 begin 7–8 years before his clinical dementia and reflect an increase in recall difficulty with a decrease in free recall in relation to intact gross recall. In SOMI-3 and SOMI-4, cues cannot recover all items missed in free recall. This indicates that memory impairment occurs approximately 1-3 years before clinical dementia.

Grober and colleagues followed 969 cognitively normal people. Knight Alzheimer’s Disease Research Center in St. Louis undergoing a clinical dementia evaluation (CDRs) is 0 at the baseline. Mean age was approximately 69 years, mean follow-up was 6.36 years for her, and 59.6% were female.

About a third (33.8%) of the participants APOE4 positive. A total of 555 underwent cerebrospinal fluid and structural MRI measurements (biomarker subgroup) and 144 were amyloid positive.Findings are based on age, gender, education, and APOE4 Status.

SOMI-1 through SOMI-4 participants had a high hazard ratio for transition from normal cognition to symptomatic cognitive impairment, defined as CDR ≥ 0.5.

SOMI-2 (HR 2.07, 95% CI 1.32-3.01) and SOMI-3/4 (HR 3.11, 95% CI 1.94-4.97) were significantly associated with the development of cognitive impairment compared with SOMI-0. was (P.both <0.001). In the biomarker and amyloid-positive status subgroups, SOMI-1 participants also showed an increased risk of cognitive impairment.

In models including amyloid and tau pathology and hippocampal volume measurements, SOMI remained a significant predictor of time to CDR ≥0.5.

Only 4.9% of participants (47) were classified as SOMI-3 or SOMI-4, limiting the interpretation of data in this group, Grober and co-authors said. Most of the participants were Caucasian and highly educated, and the results may not apply to others.