Cognitive profile of mild behavioral impairment (MBI) in brain health registry participants

Abstract

Background Non‐cognitive markers may be utilized in dementia risk assessments. Mild behavioural impairment (MBI) is a validated neurobehavioural syndrome developed by an Alzheimer’s Association‐ISTAART working group including the following criteria: 1) later life emergent and persistent neuropsychiatric symptoms; 2) representing a change from longstanding personality or patterns of behaviour; 3) not better accounted for by psychiatric conditions or life stressors. MBI as an at‐risk state for cognitive decline and dementia and may be the earliest manifestations of disease for some. We investigated whether MBI, measured with the MBI checklist, was associated with cognitive changes in older adults in the Brain Health Registry (BHR). Methods We analyzed data from 5225 participants in BHR. Participants were included if they completed Lumosity cognitive tests (memory span, reverse memory span, trailmaking, go‐no‐go) and an informant‐rated MBI‐C. We excluded participants with major neurological, psychiatric or developmental disorders. Using cutpoints to dichotomize MBI+ and MBI‐ participants (MBI‐C > 5, 6, 7), univariate ANOVA was used to determine whether people with MBI also showed impairment in cognitive test performance. ANOVAs covaried for age, sex, education, and time between test administration and MBI‐C completion. All assessments were completed remotely, using the BHR online registry. Results The final sample included 802 participants with a mean age of 66.97(SD 10.71), of which 515/802 were females (64.21%). The number and percent of MBI‐C+ participants was 62 (7.7%), 53 (6.6%), and 48 (6.0%) at cutpoints of MBI‐C >5, >6, and >7 respectively. MBI+ participants had significantly poorer memory span, poorer reverse memory span, longer trail‐making completion time, and more trail‐making errors (see Table 1 for statistical reporting). A significantly greater number of men were classified as MBI+ at all 3 cutpoints (p< 0.001). Conclusions In a large cohort of older adults in BHR, MBI assessed remotely and unsupervised using an online interface, was associated with poorer cognition in the domains of memory and executive function compared to those without MBI. Utilizing the MBI‐C in case finding may be a simple, efficient, and scalable way to detect individuals with subtle cognitive changes, for further assessment and workup, or potential inclusion in clinical trials.

Prevalence of mild behavioural impairment domains: a meta‐analysis

“…After screening, 10 studies with the prevalence of MBI domain data were included in the meta‐analysis (Table 1). 7,30,37–44 Among these studies, three were performed in Asian‐based countries, 37,39,42 and seven were performed in non‐Asian‐based countries 7,30,38,40,41,43,44 . Half of the studies (5/10) were regarded as low quality mainly because of the lack of longitudinal follow‐up of subjects (Table 2).…”

Neural correlates of the impulse dyscontrol domain of mild behavioral impairment

“…Studies have shown inflated MBI prevalence using transformed scores 21,53 in comparison to the use of the MBI checklist (MBI‐C), which is the validated a priori case ascertainment instrument developed for MBI 54 . The MBI‐C has demonstrated ability to serve as a proxy marker for older adults with subtle cognitive changes or early neurodegenerative disease 3,55 . Thus, diagnostic sensitivity of this approach may also be a limitation, as the whole breadth of MBI impulse dyscontrol, validated by network meta‐analysis 56 is not captured by the NPI‐Q.…”

Mild behavioral impairment: measurement and clinical correlates of a novel marker of preclinical Alzheimer’s disease

“…In 2016, an Alzheimer's Association working group published diagnostic criteria for MBI (Table 1), and the Mild Behavioral Impairment Checklist (MBI-C) was developed to capture the full symptom spectrum in accordance with the criteria [9,10]. The MBI-C is free, has been validated in clinical and community samples, and can be administered in person, by telephone, or unsupervised online [11][12][13][14][15][16]. Two primary questions relating to assessment using the MBI-C remain outstanding, specifically the cut points for case ascertainment, and the use of self-versus informant-reports.…”

“…Studies using the Neuropsychiatric Inventory (NPI, developed for established dementia), place prevalence as high as 49-85% in MCI and 28-75% in pre-MCI samples [19,20]. Studies using the MBI-C yield more conservative estimates of 14% in MCI and 6-9% in pre-MCI [12,13,16,17]. These estimates are more accurate due to MBI-C stipulations that symptoms emerge de novo in later life and persist for at least 6 months.…”

“…Longitudinal and cross-sectional studies have consistently linked MBI with poorer cognition and progression to MCI and dementia [16,17,21,25,[27][28][29][30]. Studies of detailed neuropsychology in cognitively normal (CN) individuals have shown differences in executive function, attention, working memory, and episodic memory associated with MBI across a number of independent studies [16,17,25,30].…”