Mild cognitive impairment with Lewy bodies: neuropsychiatric supportive symptoms and cognitive profile

<jats:title>Abstract</jats:title><jats:sec id="S0033291720002901_sec_a1"><jats:title>Background</jats:title><jats:p>Recently published diagnostic criteria for mild cognitive impairment with Lewy bodies (MCI-LB) include five neuropsychiatric supportive features (non-visual hallucinations, systematised delusions, apathy, anxiety and depression). We have previously demonstrated that the presence of two or more of these symptoms differentiates MCI-LB from MCI due to Alzheimer's disease (MCI-AD) with a likelihood ratio >4. The aim of this study was to replicate the findings in an independent cohort.</jats:p></jats:sec><jats:sec id="S0033291720002901_sec_a2" sec-type="methods"><jats:title>Methods</jats:title><jats:p>Participants ⩾60 years old with MCI were recruited. Each participant had a detailed clinical, cognitive and imaging assessment including FP-CIT SPECT and cardiac MIBG. The presence of neuropsychiatric supportive symptoms was determined using the Neuropsychiatric Inventory (NPI). Participants were classified as MCI-AD, possible MCI-LB and probable MCI-LB based on current diagnostic criteria. Participants with possible MCI-LB were excluded from further analysis.</jats:p></jats:sec><jats:sec id="S0033291720002901_sec_a3" sec-type="results"><jats:title>Results</jats:title><jats:p>Probable MCI-LB (<jats:italic>n</jats:italic> = 28) had higher NPI total and distress scores than MCI-AD (<jats:italic>n</jats:italic> = 30). In total, 59% of MCI-LB had two or more neuropsychiatric supportive symptoms compared with 9% of MCI-AD (likelihood ratio 6.5, <jats:italic>p</jats:italic> < 0.001). MCI-LB participants also had a significantly greater delayed recall and a lower Trails A:Trails B ratio than MCI-AD.</jats:p></jats:sec><jats:sec id="S0033291720002901_sec_a4" sec-type="conclusions"><jats:title>Conclusions</jats:title><jats:p>MCI-LB is associated with significantly greater neuropsychiatric symptoms than MCI-AD. The presence of two or more neuropsychiatric supportive symptoms as defined by MCI-LB diagnostic criteria is highly specific and moderately sensitive for a diagnosis of MCI-LB. The cognitive profile of MCI-LB differs from MCI-AD, with greater executive and lesser memory impairment, but these differences are not sufficient to differentiate MCI-LB from MCI-AD.</jats:p></jats:sec>