Low Accuracy of Brief Cognitive Tests in Tracking Longitudinal Cognitive Decline in an Asian Elderly Cohort.

BACKGROUND: Researchers have questioned the utility of brief cognitive tests such as the Mini-Mental Status Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) in serial administration and suggested that brief cognitive tests may not accurately track changes in Global Cognition. OBJECTIVE: To examine the accuracy of longitudinal changes on brief cognitive tests in reflecting progression in Global Cognition measured using comprehensive neuropsychological assessments. METHODS: Two hundred and seven participants were assessed with the MMSE, MoCA, and a validated comprehensive neuropsychological battery. Global z-scores on the battery were derived and used to assess overall and significant (≥0.5 standard deviation) decline on Global Cognition. Different patterns of decline on MMSE/MoCA were classified. Accuracy was examined using receiver operating characteristic curve, and sensitivity, specificity, positive (PPV) and negative (NPV) predictive values were reported. RESULTS: The overall ability of MMSE/MoCA change scores to discriminate participants who did and did not decline on Global Cognition was fair-to-moderate (AUC [95% CI] = 0.71 [0.64-0.78] & 0.73 [0.66-0.80] for overall decline; 0.78 [0.70-0.85] & 0.80 [0.73-0.86] for significant decline, respectively). Changes in MMSE/MoCA had low accuracy in identifying significant Global Cognitive Decline (PPV = 0.41 & 0.46, respectively) but high accuracy in ruling out significant decline and identifying cognitively stable participants (NPV = 0.89 & 0.88, respectively). CONCLUSION: There is limited utility in brief cognitive tests for tracking cognitive decline. Instead, they should be used for identifying participants who remain cognitively stable on follow up. These results accentuate the importance of acknowledging the limitations of brief cognitive tests when assessing cognitive change.

Cerebral microbleeds and neuropsychiatric symptoms in an elderly Asian cohort.

OBJECTIVES: Neuropsychiatric symptoms (NPS) are commonly found in patients with cerebral small vessel disease such as white matter hyperintensities and lacunar infarcts. However, the association between cerebral microbleeds (CMBs) and NPS has not been examined. Hence the present study sought to investigate the relation between CMBs and NPS in an elderly population. METHODS: This is a cross-sectional study of elderly Asians living in the community, who were assessed on a comprehensive neuropsychological battery and underwent clinical examinations as well as brain MRI scans. The 12-item neuropsychiatric inventory (NPI) was administered to a reliable informant. Total scores for individual symptoms and for NPI global performance were calculated and compared across three groups: no CMB, presence of 1 CMB and presence of multiple CMBs, controlling for demographics, vascular risk factors and other MRI markers. RESULTS: A total of 802 participants were included in the analysis. Participants with multiple CMBs had higher NPI total score compared to those with no CMB (1.06 vs 2.66, p=0.03). On individual symptom scores, higher score on depression (0.16 vs 0.53, p=0.02) and disinhibition (0.01 vs 0.14, p=0.04) was found in those elderly with multiple CMBs, independent of demographic and vascular risk factors, history of stroke, and other small vessel and large vessel disease markers. CONCLUSIONS: The presence of multiple CMBs is associated with high global neuropsychiatric disorder burden, in particular symptoms of depression and disinhibition. Future studies are recommended to investigate the importance of CMBs in the pathogenesis and longitudinal progression of neuropsychiatric disorders in the general elderly population.

Changing Patterns of Patient Characteristics in a Memory Clinic in Singapore.

OBJECTIVES: Promoting public awareness about dementia has been part of global initiatives in recent years; however, the impact on patterns of patient visits in memory clinics has not been investigated in Asian countries. Hence, the present study sought to investigate longitudinal patterns of patient characteristics among consecutive referrals to a memory clinic in Singapore from 2009 to 2015. METHODS: Consecutive first-visit patients who attended the National University Hospital memory clinic between 2009 and 2015 through referrals from primary and secondary health care services were included in the study. A retrospective review on patient demographics, clinical diagnosis, and Clinical Dementia Rating (CDR) was performed. Chi-square and logistic regression analyses were conducted to examine the changing patterns of patient characteristics over the 7-year period. RESULTS: A total of 1075 patients were included in the analysis, among whom 675 (62.8%) were diagnosed with dementia. Over the 7-year period, more dementia-free patients were seen compared to dementia patients (odds ratio [OR] = 1.70, 95% CI = 1.55-1.86). Among patients who visited the memory clinic and were subsequently diagnosed with dementia, an increasing number of mild dementia (CDR = 1) compared to moderate-to-severe dementia (CDR = 2 or 3) cases were found (OR = 1.11, 95% CI = 1.02-1.21). CONCLUSION: Changing patterns in characteristics of patients visiting the memory clinic were observed, with an increasing number of patients at a less severe stage of disease seeking medical management. These results suggest that efforts to promote awareness of dementia among the public have been effective. Future studies are recommended to confirm the causes and investigate potential consequences of the changing patterns of memory clinic patients.