Prevalence of mild behavioral impairment: A systematic review and meta‐analysis

Abstract Background Mild behavioral impairment (MBI) is a neurobehavioral syndrome characterized by later life emergent neuropsychiatric symptoms (NPS). There has not been any systematic review or meta‐analysis on the prevalence of MBI. Main aim of the study is to calculate the pooled prevalence of MBI. Method A search of the literature on MBI in mild cognitive impairment (MCI), cognitively normal (CN), and subjective cognitive impairment (SCI) and cognitively normal but at risk (CN‐AR) subjects published between 1 January 2003 and 28 September 2020 was conducted. Meta‐analysis using a random effects model was performed to determine the pooled estimate of the prevalence of MBI. Meta‐regression was performed to identify factors contributing to the variance of prevalence rate. A systematic review was also performed to study the impact of MBI in cognitive outcomes and its correlation to pathology and genetics of Alzheimer’s Disease (AD). Result Eleven studies conducting among all 15689 subjects were subjected into meta‐analysis revealing a pooled prevalence of MBI at 33.5% (95% CI 22.6‐46.6%). Seven studies conducting among 1358 MCI subjects were subjected into meta‐analysis revealing a pooled prevalence at 45.5% (95% CI 36.1‐55.3%). Four studies conducting among 13153 CN subjects were subjected into meta‐analysis revealing a pooled prevalence at 17% (95% CI 7.2‐34.9%). Five studies conducting on 1158 SCI or CN‐AR subjects were subjected into meta‐analysis revealing a pooled prevalence at 35.8% (95% CI 21.4‐53.2%). Systematic review of 13 studies showed MBI has a significant impact on cognitive deterioration, and it is associated with pathology and genetics of AD. Conclusion MBI is common in MCI, CN, and SCI and CN‐AR subjects. Our finding is potentially useful in planning future clinical trials.