Cognitive deficits 3 to 6 years before dementia onset in a population sample: the Honolulu-Asia aging study

OBJECTIVE: To determine the type of cognitive deficits occurring 3 to 6 years before onset of dementia in a population sample. DESIGN: A prospective study in which cognitive deficits in participants who had incident dementia at the 6-year follow-up were examined at baseline and 3 years. SETTING: Honolulu, Hawaii. PARTICIPANTS: Three thousand seven hundred thirty-four Japanese-American men aged 71 to 93 at baseline. At the 6-year follow-up, there were 52 incident cases of dementia, and 1,559 controls. MEASUREMENTS: The Cognitive Abilities Screening Instrument (CASI) and a questionnaire on subjective memory problems were administered at baseline. Dementia was assessed at baseline and at 3-year and 6-year follow-ups. RESULTS: Subjects who had incident dementia at 6-year follow-up, had showed deficits 3 to 6 years earlier in the CASI domain of episodic memory and in the questionnaire covering subjective memory problems. Up to 3 years before onset, there was worsening of the episodic memory deficit from baseline and new deficits in language, verbal fluency, and orientation. CONCLUSION: Cognitive deficits and awareness of memory problems are frequently present several years before dementia onset. The predictive value of these deficits is not large enough to allow earlier diagnosis of dementia, but information about such deficits may be useful as criteria for mild cognitive impairment.     

Simplifying detection of cognitive impairment: comparison of the Mini-Cog and Mini-Mental State Examination in a multiethnic sample

OBJECTIVES: To compare detection of cognitive impairment using the Mini-Cog and Mini-Mental State Examination (MMSE) and to identify sociodemographic variables that influence detection in an ethnoculturally diverse sample. DESIGN: Cross-sectional. SETTING: A registry of the University of Washington Alzheimer's Disease Research Center Satellite. PARTICIPANTS: A heterogeneous community sample (n=371) of predominantly ethnic minority elderly assessed using a standardized research protocol, 231 of whom met criteria for dementia or mild cognitive impairment (MCI). MEASUREMENTS: Demographic data, a standardized research protocol for cognitive assessment and dementia diagnosis, MMSE, and Mini-Cog. RESULTS: Both screens effectively detected cognitive impairment, the Mini-Cog slightly better than the MMSE (P<.01). Overall accuracy of classification was 83% for the Mini-Cog and 81% for the MMSE. The Mini-Cog was superior in recognizing patients with Alzheimer-type dementias (P=.05). Low education negatively affected detection using the MMSE (P<.001), whereas education did not affect the Mini-Cog, and low literacy minimally affected it. CONCLUSION: The Mini-Cog detects clinically significant cognitive impairment as well as or better than the MMSE in multiethnic elderly individuals, is easier to administer to non-English speakers, and is less biased by low education and literacy.     

Depressive symptoms and incidence of mild cognitive impairment and probable dementia in elderly women: the Women's Health Initiative Memory Study

OBJECTIVES: To examine whether significant depressive symptoms in postmenopausal women increases the risk of subsequent mild cognitive impairment (MCI) and dementia. DESIGN: Prospective cohort study. SETTING: Thirty nine of the 40 Women's Health Initiative (WHI) clinical centers that participated in a randomized clinical trial of hormone therapy. PARTICIPANTS: Six thousand three hundred seventy‐six postmenopausal women without cognitive impairment aged 65 to 79 at baseline. MEASUREMENTS: Depressive disorders were assessed using an eight‐item Burnam algorithm and followed annually for a mean period of 5.4 years. A central adjudication committee classified the presence of MCI and probable dementia based on an extensive neuropsychiatric examination. RESULTS: Eight percent of postmenopausal women in this sample reported depressive symptoms above a 0.06 cut point on the Burnam algorithm. Depressive disorder at baseline was associated with greater risk of incident MCI (hazard ratio (HR)=1.98, 95% confidence interval (CI)=1.33–2.94), probable dementia (HR=2.03, 95% CI=1.15–3.60), and MCI or probable dementia (HR=1.92, 95% CI=1.35–2.73) after controlling for sociodemographic characteristics, lifestyle and vascular risk factors, cardiovascular and cerebrovascular disease, antidepressant use, and current and past hormone therapy status. Assignment to hormone therapy and baseline cognitive function did not affect these relationships. Women without depression who endorsed a remote history of depression had a higher risk of developing dementia. CONCLUSION: Clinically significant depressive symptoms in women aged 65 and older are independently associated with greater incidence of MCI and probable dementia.     

Caring for individuals with dementia and cognitive impairment, not dementia: findings from the aging, demographics, and memory study

OBJECTIVES: To compare the characteristics and outcomes of caregivers of adults with dementia with those of caregivers of adults with cognitive impairment, not dementia (CIND). DESIGN: Cross‐sectional. SETTING: In‐home assessment for cognitive impairment and self‐administered caregiving questionnaire. PARTICIPANTS: One hundred sixty‐nine primary family caregivers of participants in the Aging, Demographics, and Memory Study (ADAMS). ADAMS participants were aged 71 and older drawn from the nationally representative Health and Retirement Study. MEASUREMENTS: Neuropsychological testing, neurological examination, clinical assessment, and medical history were used to assign a diagnosis of normal cognition, CIND, or dementia. Caregiving measures included caregiving time, functional limitations, depressive symptoms, physical and emotional strain, caregiving rewards, caregiver health, and demographic characteristics. RESULTS: Dementia caregivers spent approximately 9 hours per day providing care, compared with 4 hours per day for CIND caregivers (P=.001). Forty‐four percent of dementia caregivers exhibited depressive symptoms, compared with 26.5% of CIND caregivers (P=.03). Physical and emotional strains were similar in both groups of caregivers. Regardless of the strains, nearly all caregivers reported some benefits from providing care. Behavioral problems (P=.01) and difficulty with instrumental activities of daily living (P=.01) in persons with CIND partially explained emotional strain experienced by CIND caregivers. For those with dementia, behavioral problems predicted caregiver emotional strain (P<.001) and depressive symptoms (P=.01). CONCLUSION: Although support services are available to dementia caregivers, CIND caregivers also expend considerable time and experience strains. The real caregiver burden of cognitive impairment in the U.S. population may therefore be greatly underestimated if people who have reached the diagnostic threshold for dementia are focused on exclusively.     

Mild cognitive impairment: epidemiology and dementia risk in an elderly Italian population

OBJECTIVES: To investigate prevalence and incidence of mild cognitive impairment (MCI) and its risk of progression to dementia in an elderly Italian population.
DESIGN: Longitudinal.
SETTING: Population-based cohort aged 65 and older resident in an Italian municipality.
PARTICIPANTS: A total of 1,016 subjects underwent baseline evaluation in 1999/2000. In 2003/04, information about cognitive outcome was collected for 745 participants who were free of dementia at baseline.
MEASUREMENTS: MCI (classified as with or without impairment of the memory domain), dementia, Alzheimer's dementia (AD), and vascular dementia (VaD) diagnosed according to current international criteria.
RESULTS: Overall prevalence of MCI was 7.7% (95% confidence interval (CI)=6.1–9.7 %) and was greater with older age and poor education. During 4 years of follow-up, 155 incident MCI cases were diagnosed, with an incidence rate of 76.8 (95% CI=66.8–88.4) per 1,000 person-years. Approximately half of prevalent and incident MCI cases had memory impairment. Compared with normal cognition, multivariable-adjusted risk for progression from MCI with memory impairment to dementia was 4.78 (95% CI=2.78–8.07) for any dementia, 5.92 (95% CI=3.20–10.91) for AD, and 1.61 (95% CI=0.37–7.00) for VaD. No association with dementia risk was found for MCI without memory impairment. Approximately one-third of MCI cases with memory impairment did not progress to dementia.
CONCLUSION: MCI occurs often in this elderly Italian cohort and is associated with greater risk of AD, but only when the impairment involves the memory domain. However, a substantial proportion of MCI cases with memory impairment do not progress to dementia.     

Implementing a screening and diagnosis program for dementia in primary care

BACKGROUND: Primary care physicians are positioned to provide early recognition and treatment of dementia. We evaluated the feasibility and utility of a comprehensive screening and diagnosis program for dementia in primary care. METHODS: We screened individuals aged 65 and older attending 7 urban and racially diverse primary care practices in Indianapolis. Dementia was diagnosed according to International Classification of Diseases (ICD)-10 criteria by an expert panel using the results of neuropsychologic testing and information collected from patients, caregivers, and medical records. RESULTS: Among 3,340 patients screened, 434 scored positive but only 227 would agree to a formal diagnostic assessment. Among those who completed the diagnostic assessment, 47% were diagnosed with dementia, 33% had cognitive impairment—no dementia (CIND), and 20% were considered to have no cognitive deficit. The overall estimated prevalence of dementia was 6.0% (95% confidence interval (CI) 5.5% to 6.6%) and the overall estimate of the program cost was $128 per patient screened for dementia and $3,983 per patient diagnosed with dementia. Only 19% of patients with confirmed dementia diagnosis had documentation of dementia in their medical record. CONCLUSIONS: Dementia is common and undiagnosed in primary care. Screening instruments alone have insufficient specificity to establish a valid diagnosis of dementia when used in a comprehensive screening program; these results may not be generalized to older adults presenting with cognitive complaints. Multiple health system and patient-level factors present barriers to this formal assessment and thus render the current standard of care for dementia diagnosis impractical in primary care settings. Supported by grant R01 HS10884-01 from the Agency for Healthcare Research and Quality.     

Undiagnosed dementia and value of serial cognitive impairment screening in developing countries: A population-based study

Background:   We conducted a population-based prospective study in 420 older persons to examine the prevalence of undiagnosed dementia and validity of the Chula Mental Test (CMT) as well as value of serial administration of the CMT and its score evolution over 2 years.
Methods:   The CMT score was obtained in 1997 and 1999 surveys. In 1999, all participants were evaluated by a geriatrician to make diagnoses of dementia according to the 4th edn of the Diagnostic and Statistical Manual criteria. Information on previous diagnosis of dementia by physicians was collected. Validity of the CMT was determined by the receiver–operator curve. The pattern of cognitive evolution over 2 years was analyzed.
Results:   Of 420 subjects, 23 had dementia, of which 22 (95.6%) were undiagnosed. The prevalence (95% confidence interval) of dementia and undiagnosed dementia were 5.5% (3.3–7.7%) and 5.3% (4.1–6.3%), respectively. With original cut-off (15/14) of the CMT, the sensitivity and specificity were 0.74 and 0.86, respectively. The best cut-off found in this study was 16/15 which provided better sensitivity (0.91) but worse specificity (0.76) than those of the original cut-off. Pattern of cognitive evolution was heterogeneous. The heterogeneous change was substantial in subjects with mild low CMT score. Cognitive evolution pattern showed that serial administration of the CMT could reduce workload of primary care physicians and might be useful in a screening protocol.
Conclusion:   The prevalence of undiagnosed dementia in community-dwelling Thai older persons was high. The CMT was valid for use in a community. Heterogeneous evolution of cognitive function and value of serial cognitive impairment screening was found.     

Impact of mean blood pressure and blood pressure variability after diagnosis of mild cognitive impairment and risk of dementia

Hypertension and increased blood pressure variability (BPV) are associated with the development of dementia. However, previous studies did not focus on the risk of dementia among participants with mild cognitive impairment (MCI) and controlled blood pressure level. To address this limitation, the authors performed a post‐hoc analysis of SPRINT MIND participants diagnosed with MCI (mean Montreal Cognitive Assessment score at diagnosis 16.1±3.1). The primary outcome was subsequent diagnosis of probable dementia. The exposure was mean blood pressure and BPV following MCI diagnosis until the end of follow‐up or a dementia event (mean follow‐up 2.6±1.2 years). The primary outcome occurred in 76/516 (14.7%) patients. The mean blood pressure was not significantly higher in participants who developed dementia. In the lowest quartile of BPV (systolic standard deviation), the rate of dementia was 8.5% (11/129), while in the highest quartile it was 21.7% (28/129). The highest quartile of systolic BPV had an adjusted hazard ratio for dementia of 2.73 (95% CI, 1.31–5.69) and for diastolic BPV it was 2.62 (95% CI, 1.26–5.47). In SPRINT MIND participants, the authors found that increased BPV after MCI diagnosis was associated with incident probable dementia during subsequent follow‐up.     

Mild cognitive impairment subtypes and vascular dementia in community-dwelling elderly people: a 3-year follow-up study

OBJECTIVES: To investigate whether mild cognitive impairment (MCI) with multiple impaired cognitive domains (mcd-MCI) is a prodromal manifestation of vascular dementia (VaD). DESIGN: Prospective cohort study. SETTING: Geriatric unit of the Ospedale Maggiore Istituto di Ricovero e Cura a Carattere Scientifico, Milan, Italy. PARTICIPANTS: Four hundred community-dwelling subjects aged 65 and older who came freely to the geriatric unit as part of a comprehensive geriatric assessment program were evaluated for memory impairment or other cognitive disorders. Subjects with MCI were kept under observation for 3 years. MEASUREMENTS: Subjects with MCI were studied by applying a standardized clinical evaluation and a conducting a computed tomography brain scan. Cognitive performance was assessed using the Mini-Mental State Examination, the Clock Drawing Test, and a comprehensive battery of neuropsychological tests. Cardiovascular comorbidity was assessed on the basis of medical history and using electrocardiography, echocardiography, and carotid color Doppler ultrasound. RESULTS: MCI was found in 65 of the 400 community-dwelling subjects; 31 were classified with amnestic MCI (a-MCI) and 34 with mcd-MCI. A dysexecutive syndrome characterized people with mcd-MCI, who had significantly more vascular comorbidity and signs of vascular disease on brain imaging as well as a higher prevalence of extra pyramidal features, mood disorders, and behavioral symptoms than people with a-MCI. Twenty of the 65 subjects with MCI (31%) progressed to dementia within 3 years of follow-up: 11 subjects with Alzheimer's disease (AD) and nine with VaD. All patients who evolved to AD had been classified with a-MCI at baseline, whereas all patients who evolved to subcortical VaD had been classified with mcd-MCI at baseline. CONCLUSION: All subjects who converted to subcortical VaD had been classified with mcd-MCI, suggesting that mcd-MCI might be an early stage of subcortical VaD.     

Acupuncture for amnestic mild cognitive impairment: A pilot multicenter,randomized, parallel controlled trial

Introduction:Patients with amnesic mild cognitive impairment (aMCI) are more likely to develop Alzheimer disease than corresponding age normal population. Because Alzheimer disease is irreversible, early intervention for aMCI patients seems important and urgent. We have designed a pilot multicenter, randomized, parallel controlled trial to assess the efficacy and safety of acupuncture on aMCI, explore the feasibility of acupuncture in the treatment of aMCI, so as to provide a reference for large-sample clinical trials in the next stage.Method:We designed a pilot multicenter, randomized, parallel controlled trial. This trial aims to test the feasibility of carrying out a large-sample clinical trial. In this trial, 50 eligible patients with aMCI will be included and allocated to acupuncture group (n = 25) or sham acupuncture group (n = 25) at random. Subjects will accept treatment 2 times a week for 12 weeks continuously, with a total of 24 treatment sessions. We will select 6 acupoints (GV20, GV14, bilateral BL18, bilateral BL23). For the clinical outcomes, the primary outcome is Montreal cognitive assessment, which will be assessed from baseline to the end of this trial. And the secondary outcomes are Mini-mental State Examination, Delayed Story Recall, Clinical Dementia Rating scale, Global Deterioration Scale, Activity of Daily Life, Alzheimer Disease Assessment Scale-Cognitive Section, brain magnetic resonance imaging, brain functional magnetic resonance imaging, and event-related potential P300, which will be assessed before and after treatment. In addition, we will assess the safety outcomes from baseline to the end of this trial and feasibility outcome after treatment. We will evaluate neuropsychological assessment scale (Montreal cognitive assessment, Mini-mental State Examination, Alzheimer Disease Assessment Scale-Cognitive Section) at 3 months and 6 months after treatment.Discussion:This pilot trial aims to explore the feasibility of the trial, verify essential information of its efficacy and safety. This pilot study will provide a preliminary basis for carrying out a larger clinical trial of acupuncture on aMCI in near future.     

Diabetes as a risk factor for dementia and mild cognitive impairment: a meta-analysis of longitudinal studies

This study examined the association of diabetes with the onset of dementia (including Alzheimer's disease (AD), vascular dementia (VD) and any dementia) and mild cognitive impairment (MCI) by using a quantitative meta-analysis of longitudinal studies. EMBASE and MEDLINE were searched for articles published up to December 2010. All studies that examined the relationship between diabetes and the onset of dementia or MCI were included. Pooled relative risks were calculated using fixed and random effects models. Nineteen studies met our inclusion criteria for this meta-analysis, and 6184 subjects with diabetes and 38 530 subjects without diabetes were included respectively. All subjects were without dementia or MCI at baseline. The quantitative meta-analysis showed that subjects with diabetes had higher risk for AD (relative risk (RR):1.46, 95% confidence interval (CI): 1.20-1.77), VD (RR: 2.48, 95% CI: 2.08-2.96), any dementia (RR: 1.51, 95% CI: 1.31-1.74) and MCI (RR: 1.21, 95% CI: 1.02-1.45) than those without. The quantitative meta-analysis showed that diabetes was a risk factor for incident dementia (including AD, VD and any dementia) and MCI.     

Associations between dementia/mild cognitive impairment and cognitive performance and activity levels in youth

OBJECTIVES: To study the associations between dementia/mild cognitive impairment (MCI) and cognitive performance and activity levels in youth. DESIGN: Retrospective cohort study. SETTING: Research volunteers living throughout the United States. PARTICIPANTS: A total of 396 persons (mean age 75) who were graduates of the same high school in the mid-1940s. MEASUREMENTS: Adolescent intelligence quotient (IQ) scores were gathered from archived student records, and activity levels were determined from yearbooks. A two-stage telephone screening procedure (Modified Telephone Interview for Cognitive Status or Informant Questionnaire on Cognitive Decline in the Elderly followed by Dementia Questionnaire) was used to determine adult cognitive status. Data were analyzed using logistic regression to model the risk of cognitive impairment (dementia/MCI) versus no cognitive impairment as a function of IQ and activity level, adjusting for sex and education. RESULTS: High adolescent IQ and greater activity level were each independently associated with a lower risk for dementia/MCI (odds ratio (OR) for a 1-standard deviation increase in IQ=0.51, 95% confidence interval (CI)=0.32-0.79; OR for a unit increase in activity=0.32, 95% CI=0.12-0.84). No association was found between sex or education and adult cognitive status in this model. CONCLUSION: High IQ and greater activity levels in youth reduce the risk for cognitive impairments in aging. The mechanism(s) underlying these associations are unknown, but intelligence may be a marker for cognitive/neurological "reserve," and involvement in activities may contribute to "reserve." Early neuropathology and ascertainment bias are also possible explanations for the observed associations.     

Accelerated weight loss and incident dementia in an elderly African-American cohort

OBJECTIVES: To examine the association between changes in body mass index (BMI), dementia, and mild cognitive impairment (MCI). DESIGN: Prospective observational study. SETTING: Urban community in Indianapolis, Indiana. PARTICIPANTS: Participants were African Americans aged 65 and older enrolled in the Indianapolis Dementia Project and followed through 2007. This analysis included 1,331 participants who did not have dementia at their first BMI measurement. MEASUREMENTS: Cognitive assessment and clinical evaluations were conducted every other year to identify participants with dementia or MCI during 12 years of follow‐up (mean follow‐up 6.4 years). BMI measures; alcohol and smoking history; and medical conditions including history of cancer, hypertension, diabetes mellitus, heart attack, stroke; and depression were collected at each follow‐up evaluation. Mixed‐effect models were used to examine the differences in BMI between participants who developed dementia or MCI and those who did not, adjusting for covariates. RESULTS: Mean BMI at baseline was 29.8 ± 5.7 for women and 28.3 ± 4.8 for men. Participants with incident dementia or MCI had greater decline in BMI than those without (P=.02 for dementia, P=.04 for MCI). BMI in participants with incident dementia, MCI, and normal cognition did not differ 12 or 9 years before diagnosis, but 6 years before diagnosis, participants with incident dementia had significantly lower BMI than participants with normal cognition (P=.03), as did participants with MCI (P=.006). CONCLUSION: Decline in BMI appears to be an early marker for dementia. There is a need for the close monitoring of weight loss in older adults.     

西安城区群居老人痴呆的流行病学调查与分析

目的 调查西安城区群居老人痴呆现况,分析其危险因素. 方法 采用人口学、健康史、简易精神状态检查量表(MMSE)、日常生活活动能力(ADL)量表、长谷川痴呆检查量表(HDS)等问卷和量表进行筛查. 结果 西安城区群居老人痴呆的患病率为36.7%,明显高于其他老年人群;患病率随年龄的增长和ADL的下降而升高,随文化程度的升高而降低,高龄、养老院居住场所和ADL障碍是老年痴呆的独立危险因素. 结论 西安城区群居老人痴呆患病率较高,尤其是养老院场所的老人.