Prevalence and subtypes of dementia in southern Taiwan: impact of age, sex, education, and urbanization

Classification Prediction of Alzheimer's Disease and Vascular Dementia Using Physiological Data and ECD SPECT Images

Alzheimer's disease (AD) and vascular dementia (VaD) are the two most common forms of dementia. However, their neuropsychological and pathological features often overlap, making it difficult to distinguish between AD and VaD. In addition to clinical consultation and laboratory examinations, clinical dementia diagnosis in Taiwan will also include Tc-99m-ECD SPECT imaging examination. Through machine learning and deep learning technology, we explored the feasibility of using the above clinical practice data to distinguish AD and VaD. We used the physiological data (33 features) and Tc-99m-ECD SPECT images of 112 AD patients and 85 VaD patients in the Taiwanese Nuclear Medicine Brain Image Database to train the classification model. The results, after filtering by the number of SVM RFE 5-fold features, show that the average accuracy of physiological data in distinguishing AD/VaD is 81.22% and the AUC is 0.836; the average accuracy of training images using the Inception V3 model is 85% and the AUC is 0.95. Finally, Grad-CAM heatmap was used to visualize the areas of concern of the model and compared with the SPM analysis method to further understand the differences. This research method can quickly use machine learning and deep learning models to automatically extract image features based on a small amount of general clinical data to objectively distinguish AD and VaD.

Sarcopenia and diabetes-induced dementia risk

This study aimed to investigate whether sarcopenia independently increases the risk of diabetes-induced dementia in elderly individuals diagnosed with type 2 diabetes mellitus. The study cohort consisted of a large sample of elderly individuals aged 60 years and above, who were diagnosed with type 2 diabetes mellitus between 2008 and 2018. To minimize potential bias and achieve covariate balance between the sarcopenia and non-sarcopenia groups, we employed propensity score matching. Various statistical analyses, including Cox regression models to assess dementia risk and associations, competing risk analysis to account for mortality and Poisson regression analysis for incidence rates, were used. Before propensity score matching, the study included 406 573 elderly type 2 diabetes mellitus patients, with 20 674 in the sarcopenia group. Following propensity score matching, the analysis included a total of 41 294 individuals, with 20 647 in the sarcopenia group and 20 647 in the non-sarcopenia group. Prior to propensity score matching, elderly type 2 diabetes mellitus patients with sarcopenia exhibited a significantly higher risk of dementia (adjusted hazard ratio: 1.12, 95% confidence interval: 1.07-1.17). After propensity score matching, the risk remained significant (adjusted hazard ratio: 1.14, 95% confidence interval: 1.07-1.21). Incidence rates of dementia were notably higher in the sarcopenia group both before and after propensity score matching, underscoring the importance of sarcopenia as an independent risk factor. Our study highlights sarcopenia as an independent risk factor for diabetes-induced dementia in elderly type 2 diabetes mellitus patients. Advanced age, female gender, lower income levels, rural residency, higher adapted diabetes complication severity index and Charlson Comorbidity Index scores and various comorbidities were associated with increased dementia risk. Notably, the use of statins was linked to a reduced risk of dementia. This research underscores the need to identify and address modifiable risk factors for dementia in elderly type 2 diabetes mellitus patients, offering valuable insights for targeted interventions and healthcare policies.

CERAD (Consortium to Establish a Registry for Alzheimer's Disease) Neuropsychology Assessment Battery: 35 Years and Counting

BACKGROUND

In 1986, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) was mandated to develop a brief neuropsychological assessment battery (CERAD-NAB) for AD, for uniform neuropsychological assessment, and information aggregation. Initially used across the National Institutes of Aging-funded Alzheimer's Disease Research Centers, it has become widely adopted wherever information is desired on cognitive status and change therein, particularly in older populations.

OBJECTIVE

Our purpose is to provide information on the multiple uses of the CERAD-NAB since its inception, and possible further developments.

METHODS

Since searching on "CERAD neuropsychological assessment battery" or similar terms missed important information, "CERAD" alone was entered into PubMed and SCOPUS, and CERAD-NAB use identified from the resulting studies. Use was sorted into major categories, e.g., psychometric information, norms, dementia/differential dementia diagnosis, epidemiology, intervention evaluation, genetics, etc., also translations, country of use, and alternative data gathering approaches.

RESULTS

CERAD-NAB is available in ∼20 languages. In addition to its initial purpose assessing AD severity, CERAD-NAB can identify mild cognitive impairment, facilitate differential dementia diagnosis, determine cognitive effects of naturally occurring and experimental interventions (e.g., air pollution, selenium in soil, exercise), has helped to clarify cognition/brain physiology-neuroanatomy, and assess cognitive status in dementia-risk conditions. Surveys of primary and tertiary care patients, and of population-based samples in multiple countries have provided information on prevalent and incident dementia, and cross-sectional and longitudinal norms for ages 35-100 years.

CONCLUSION

CERAD-NAB has fulfilled its original mandate, while its uses have expanded, keeping up with advances in the area of dementia.

Association between Periodontal Disease and Cognitive Impairment in Adults

INTRODUCTION

Periodontitis is a severe oral infection that can contribute to systemic inflammation. A large body of evidence suggests a role for systemic inflammation in the initiation of neurodegenerative disease. This systematic review synthesized data from observational studies to investigate the association between periodontitis and neuroinflammation in adults.

METHODS AND MATERIALS

A systematic literature search of PubMed, Web of Science, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) was performed for studies published from the date of inception up to September 2021. Search terms for the exposure "oral disease" and outcome "dementia", "neuroinflammation" and "cognitive decline" were used. Study selection and data extraction were independently undertaken by two reviewers. The final eligible articles were included only if the exposure is periodontitis and the outcome is cognitive impairment or dementia or a topic related to this condition, and if the study was conducted in an adult population. The quality and risk of bias were assessed by Newcastle Ottawa Scale (NOS). Qualitative synthesis was used to narratively synthesize the results. Six cohort studies, three cross-sectional studies, and two case-control studies met the inclusion criteria. These eleven studies were only narratively synthesized. Meta-analysis was not performed due to the methodological heterogeneity of the studies.

RESULTS

The results of included studies show that chronic periodontitis patients with at least eight years of exposure are at higher risk of developing cognitive decline and dementia. Oral health measures such as gingival inflammation, attachment loss, probing depth, bleeding on probing, and alveolar bone loss are associated with cognitive impairment. The reduction of epidermal growth factor (EGF), interleukin 8 (IL-8), interferon γ-induced protein 10 (IP-10), and monocyte chemoattractant protein-1 (MCP-1) in addition to over expression of interleukin 1-β (IL-1β) are significant in patients suffering from cognitive decline with pre-existing severe periodontitis.

CONCLUSIONS

All the included studies show evidence of an association between periodontitis and cognitive impairment or dementia and Alzheimer's disease pathology. Nonetheless, the mechanisms responsible for the association between periodontitis and dementia are still unclear and warrant further investigation.

Use of Hormone Replacement Therapy and Risk of Dementia: A Nationwide Cohort Study

BACKGROUND AND OBJECTIVES

Estrogen has the potential to influence brain physiology implicated in dementia pathogenesis. Hormone replacement therapy (HRT) might be expected to influence the risk of dementia. Observational data indicated that HRT was associated with reductions in dementia risk, but experimental evidence demonstrates that HRT increases the incidence of dementia. To determine the effect of HRT on the risk of dementia, a retrospective cohort study was performed using a nationwide claims dataset in Taiwan.

METHODS

A population-based longitudinal study was performed using data from the Longitudinal Health Insurance Database in Taiwan. A total of 35,024 women with HRT were enrolled as the exposed cohort and 70,048 women without HRT were selected on the basis of propensity matching as the comparison cohort. All participants were followed up until the diagnosis of dementia, death, or at the end of December 31, 2013, whichever occurred first. Overall, the average duration of follow-up (±SD) in the HRT and comparison cohorts was 12.3 (±2.3) and 12.2 (±2.4), respectively. The Cox proportional hazards regression models were conducted to produce hazard ratios (HRs) with 95% CIs to evaluate the association of HRT with the risk of dementia.

RESULTS

In the follow-up period, the cumulative incidence of dementia for the HRT cohort (20.04 per 1,000) was significantly higher than the corresponding cumulative incidence for the comparison cohort (15.79 per 1,000), resulting in an adjusted HR of 1.35 (95% CI 1.13-2.62). There was an increased risk of dementia with a higher cumulative dose of HRT prescription (p for trend <0.0001).

DISCUSSION

This cohort study documented that HRT was associated with an increased risk of dementia. The clinical implications of this study merit further investigations.

The Usage of Histamine Type 1 Receptor Antagonist and Risk of Dementia in the Elderly: A Nationwide Cohort Study

Background

The histamine type 1 receptor antagonist (H1RA) has been commonly used. This study aimed to examine the association between the usage of H1RA and the risk of dementia.

Methods

A total of 8,986 H1RA users aged ≥50 and 26,958 controls matched a ratio of 1:3 for age, sex, and comorbidity, were selected between January 1, and December 31, 2000, from Taiwan’s National Health Insurance Research Database. Fine and Gray’s survival analysis (competing with mortality) was used to compare the risk of developing dementia during a 15-year follow-up period (2000–2015).

Results

In general, the H1RA usage was not significantly associated with dementia (adjusted subdistribution hazard ratio [SHR] = 1.025, 95% confidence interval [CI] = 0.883–1.297, p = 0.274) for the H1RA cohort. However, a differential risk was found among the groups at risk. The patients with the usage of H1RA aged ≥65 years (adjusted SHR: 1.782, 95% CI = 1.368–2.168, p &lt; 0.001) were associated with a higher risk of dementia, in comparison to the control groups. Furthermore, the patients with the usage of H1RA that were male, or had more comorbidities, were also associated with an increased risk of dementia.

Conclusion

The usage of H1RA was associated with the risk of developing dementia in the patients aged ≥ 65 years.

The Association Between Dextromethorphan Use and the Risk of Dementia

Dementia is one of neurodegenerative disease without preventive medicine currently. Dextromethorphan (DXM) has been reported to reduce neuronal damage and neurodegeneration in animal and human models. The effect of DXM on the dementia has not been fully examined. We examined the medical records over 40 years old in Taiwan's National Health Insurance Research Database between 2000 and 2015 to establish matched cohorts. We used a Cox regression hazard model to identify risk factors of dementia during 16 years of follow-up, and the results indicate that a significantly lower percentage of subjects with DXM use (P < .001) developed dementia compared with those without DXM use (11.38%, 4541/39 895 vs 18.66%, 29 785/159 580). After adjustment for age and other variables [adjusted hazard ratio: .567 (95% confidence interval: .413-.678, P < .001)], this study also demonstrated that DXM use appeared to reduce the risk of developing dementia. DXM use may potentially provide a protective effect against dementia.

Validation of the Taiwanese Version of ACE-III (T-ACE-III) to Detect Dementia in a Memory Clinic

OBJECTIVE

The Addenbrooke's Cognitive Examination III (ACE-III) is a 100-points cognitive test used in detecting dementia in many countries. There has been no validation study of the ACE-III in patients with suspected dementia in a Taiwanese population, where the language is traditional Chinese. We aimed to culturally adapt and validate the ACE-III as a cognitive assessment tool for differentiating between people with and without dementia presenting to healthcare professionals in Taiwan with possible dementia.

METHODS

We culturally adapted the ACE-III for Taiwan (T-ACE-III) and tested it with consenting patients with suspected dementia in northern Taiwan who had been through the diagnostic process. We calculated receiver operating characteristic (ROC) curves to test the ability of the T-ACE-III to differentiate between dementia and non-dementia cases using clinician diagnosis as the gold standard. We generated the Youden Index to determine the best cut-off score.

RESULTS

We recruited 90 Taiwanese individuals aged 49-93 years: 24 males and 33 females had dementia and 12 males and 21 females did not. The area under the ROC curve was 0.99 for distinguishing dementia from non-dementia. The T-ACE-III had a sensitivity of 100% and specificity of 78.8% when the cut-off score was 86/87. With a cut-off value of 73/74, the specificity was 100.0%, and sensitivity 89.5%. The highest Youden Index was 0.895, indicating the best overall cut-off point to be 73/74.

CONCLUSIONS

The T-ACE-III is an acceptable cognitive test with excellent psychometric properties for discriminating dementia from non-dementia in Taiwanese populations in memory clinic settings.

Risk of dementia in patients with toxoplasmosis: a nationwide, population-based cohort study in Taiwan

Background

Approximately 25–30% of individuals worldwide are infected with Toxoplasma gondii (T. gondii), which is difficult to detect in its latent state. We aimed to evaluate the association between toxoplasmosis, the risk of dementia, and the effects of antibiotics in Taiwan.

Methods

This nationwide, population-based, retrospective cohort study was conducted using the Longitudinal Health Insurance Database containing the records of 2 million individuals retrieved from Taiwan’s National Health Insurance Research Database. Fine–Gray competing risk analysis was used to determine the risk for the development of dementia in the toxoplasmosis cohort relative to the non-toxoplasmosis cohort. A sensitivity analysis was also conducted. The effects of antibiotics (sulfadiazine or clindamycin) on the risk of dementia were also analyzed.

Results

We enrolled a total of 800 subjects, and identified 200 patients with toxoplasmosis and 600 sex- and age-matched controls without toxoplasmosis infection in a ratio of 1:3, selected between 2000 and 2015. The crude hazard ratio (HR) of the risk of developing dementia was 2.570 [95% confidence interval (CI) = 1.511–4.347, P < 0.001]. After adjusting for sex, age, monthly insurance premiums, urbanization level, geographical region, and comorbidities, the adjusted HR was 2.878 (95% CI = 1.709–4.968, P < 0.001). Sensitivity analysis revealed that toxoplasmosis was associated with the risk of dementia even after excluding diagnosis in the first year and the first 5 years. The usage of sulfadiazine or clindamycin in the treatment of toxoplasmosis was associated with a decreased risk of dementia.

Conclusions

This finding supports the evidence that toxoplasmosis is associated with dementia and that antibiotic treatment against toxoplasmosis is associated with a reduced risk of dementia. Further studies are necessary to explore the underlying mechanisms of these associations.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-04928-7.

A Scoping Review of the Association of Social Disadvantage and Cerebrovascular Disease Confirmed by Neuroimaging and Neuropathology

Social disadvantage—a state of low-income, limited education, poor living conditions, or limited social support—mediates chronic health conditions, including cerebrovascular disease. Social disadvantage is a key component in several health impact frameworks, providing explanations for how individual-level factors interact with interpersonal and environmental factors to create health disparities. Understanding the association between social disadvantage and vascular neuropathology, brain lesions identified by neuroimaging and autopsy, could provide insight into how one’s social context interacts with biological processes to produce disease. The goal of this scoping review was to evaluate the scientific literature on the relationship between social disadvantage and cerebrovascular disease, confirmed through assessment of vascular neuropathology. We reviewed 4049 titles and abstracts returned from our search and included records for full-text review that evaluated a measure of social disadvantage as an exposure variable and cerebrovascular disease, confirmed through assessment of vascular neuropathology, as an outcome measure. We extracted exposures and outcomes from 20 articles meeting the criteria after full-text review, and described the study findings and populations sampled. An improved understanding of the link between social factors and cerebrovascular disease will be an important step in moving the field closer to addressing the fundamental causes of disease and towards more equitable brain health.

The Prevalence of Dementia: A Systematic Review and Meta-Analysis

Dementia is a severe neurodegenerative disorder and it can be categorized into several subtypes by different pathogenic causes. We sought to comprehensively analyzed the prevalence of dementia from perspectives of geographic region (Asia, Africa, South America, and Europe/North America), age, and gender. We searched PubMed and EMBASE for relevant articles on dementia published from January 1985 to August 2019. In these studies, analyses were stratified by geographic region, age, and gender. Meta-regression was conducted to identify if there were significant differences between groups. We included forty-seven studies. Among the individuals aged 50 and over in the community, the pooled prevalence for all-cause dementia, Alzheimer's disease, and vascular dementia were 697 (CI95%: 546-864) per 10,000 persons, 324 (CI95%: 228-460) per 10,000 persons, and 116 (CI95%: 86-157) per 10,000 persons, respectively. In our study, the prevalence of all-type dementia in individuals aged 100 years and older (6,592 per 10,000 cases) is 244 times higher than in those aged 50-59 (27 per 10,000 cases). The number of people living with dementia approximately doubles every five years. The prevalence was greater in women than in men (788 cases versus 561 cases per 10,000 persons) in overall analysis. In individuals aged 60 to 69 years, AD prevalence in females was 1.9 times greater than that in males (108 cases versus 56 cases per 10,000 persons), while the prevalence of VaD was 1.8 times greater in males than in females (56 cases versus 32 cases per 10,000 persons). Prevalence rate was higher in Europe and North America than in Asia, Africa, and South America.

Sex as a Risk Factor for Developing Cognitive Impairments in National Alzheimer's Coordinating Center Participants

Background:

It is inconclusive on how sex affects the risk of developing mild cognitive impairment (MCI) or dementia.

Objective:

To investigate how sex affects the risk of developing MCI or dementia.

Methods:

A secondary data analysis was performed on data collected from participants enrolled at Alzheimer’s Disease Research Centers funded by National Institute on Aging. There were two inclusion criteria: 1) participants were free of dementia at the baseline visit; 2) every participant must have at least one follow-up visit. A Cox proportional hazards model was used to investigate how sex affects the risk of developing cognitive impairments.

Results:

During a follow-up period of more than 10 years, male participants had a slightly higher incidence than female participants for either MCI or dementia. Not surprisingly, a higher prevalence was observed in male than female participants for either MCI or dementia. However, male participants had a higher mortality rate than their female counterparts.

Conclusion:

The male sex is associated with a higher risk for developing cognitive impairments along the aging process.

Association between amphetamine-related disorders and dementia-a nationwide cohort study in Taiwan

Objective

We have conducted a study to clarify the association between amphetamine‐related disorders (ARD) and the risk of developing dementia.

Methods

This study used a retrospective cohort design by using Taiwan’s National Health Research Institute Database. A random sample of 68,300 subjects between January 1, 2000, and December 31, 2015, was obtained, comprising of 17,075 patients with ARD, and 51,225 controls without ARD (1:3), matched for gender and age group. After adjusting for covariates, a Fine and Gray’s survival analysis (competing with mortality) was used to compare the risk of dementia during a 15‐year follow‐up period.

Results

In the present study, 1,751 of 17,075 patients with ARD and 2,147 of 51,225 in the control group without ARD (883.10 vs 342.83 per 100,000 person‐years) developed dementia. ARD cohort was more likely to develop dementia (hazard ratio = 4.936 [95% CI: 4.609–5.285, P < 0.001). After adjusting for gender, age groups, education, monthly insured premiums, urbanization level, geographic region, comorbidities, the hazard ratio for ARD patients was 5.034 (95% CI: 4.701–5.391, P < 0.001). ARD has been associated with overall dementia, Alzheimer dementia, vascular dementia, and other dementia. Both the amphetamine use disorder and amphetamine‐induced psychotic disorders were associated with the risk of overall dementia, Alzheimer dementia, vascular dementia, and other dementia.

Interpretation

This study shows that patients with ARD, both the amphetamine use disorder and the amphetamine‐induced psychotic disorder, may have a nearly fivefold risk of developing dementia, including Alzheimer dementia and other types of dementia.

New Users of Herbal Medicine Containing Aristolochic Acids and the Risk of Dementia in the Elderly: A Nationwide, Population-Based Study in Taiwan

BACKGROUND

Herbal medicine containing aristolochic acids (HMCAA) was used for inflammatory and infectious diseases. This study aimed to investigate the association between the usage of HMCAA and the risk of dementia.

METHODS

A total of 199 new users of HMCAA were enrolled, along with 597 controls without the usage of HMCAA, at a ratio of 1:3 - matched by age, sex, and comorbidity, between 2000 and 2003 - from the National Health Research Institutes Database (NHRID) of Taiwan, which contains two million randomly sampled subjects, in this cohort study. We used Fine and Gray's survival analysis (competing with mortality) to compare the risk of developing dementia during a 15-year follow-up period (2000-2015).

RESULTS

In general, HMCAA was not significantly associated with dementia (adjusted subdistribution hazard ratio [SHR] = 0.861, 95% confidence interval [CI] = 0.484-1.532, p = 0.611) for the HMCAA-cohort, although differential risk was observed among the groups at risk. The patients with usage of HMCAA aged ≧ 85 years were associated with a higher risk in dementia (adjusted SHR: 6.243, 95% CI=1.258-21.084, p = 0.001), in comparison to those aged 50-54 years. Furthermore, the patients with usage of HMCAA that had cerebrovascular accidents were associated with an increased risk of dementia.

CONCLUSION

The usage of HMCAA was associated with the risk of developing dementia in the patients aged ≧ 85 years.

No Association Between Human Immunodeficiency Virus Infections And Dementia: A Nationwide Cohort Study In Taiwan

BACKGROUND

The associations between the human immunodeficiency virus (HIV) and dementias are as yet to be studied in Taiwan. The aim of this study is to clarify as to whether HIV infections are associated with the risk of dementia.

METHODS

A total of 1,261 HIV-infected patients and 3,783 controls (1:3) matched for age and sex were selected between January 1 and December 31, 2000 from Taiwan's National Health Insurance Research Database (NHIRD). Fine and Gray's survival analysis (competing with mortality) analyzed the risk of dementias during the 15-year follow up. The association between the highly active antiretroviral therapy (HAART) and dementia was analyzed by stratifying the HAART status among the HIV subjects.

RESULTS

During the follow-up period, 25 in the HIV group (N= 1,261) and 227 in the control group (N= 3,783) developed dementia (656.25 vs 913.15 per 100,000 person-years). Fine and Gray's survival analysis revealed that the HIV patients were not associated with an increased risk of dementia, with the adjusted hazard ratio (HR) as 0.852 (95% confidence interval [CI]: 0.189-2.886, p=0.415) after adjusting for sex, age, comorbidities, geographical region, and the urbanization level of residence. There was no significant difference between the two groups of HIV-infected patients with or without HAART in the risk of dementia.

CONCLUSION

This study found that HIV infections, either with or without HAART, were not associated with increased diagnoses of neurodegenerative dementias in patients older than 50 in Taiwan.

Educational effects on ascertain dementia 8-item informant questionnaire to detect dementia in the Taiwanese population

ABSTRACTBackground:Dementia screening is a public health priority in Taiwan, where the prevalence of dementia is increasing because of an aging population. However, the reasons affect community-dwelling people to accept a referral to memory specialist clinic after dementia screening was still unclear. To investigate the feasibility, acceptability, sensitivity, and specificity of the ascertain dementia 8-item informant questionnaire (AD8) to screen for patients with cognitive impairments in Taiwan's primary healthcare system.

METHODS

Researchers invited community-dwelling people whose age was above 50-year-old to attend the Memory Screening Project. AD8 was used to perform the informant interview with adult patients who were attending the Memory Screening Project in Taiwan. Individuals who scored ≥2 on the AD8 was suggested to accept referral for further cognitive performance evaluation tests, which included three validated dementia tests, i.e. the Mini-Mental Screening Examination (MMSE), the Cognitive Abilities Screening Instrument (CASI), and the Clinical Dementia Rating (CDR).

RESULTS

Of the 102 participants who scored ≥2 on the AD8, only 25.5% attended the referral appointment. In participants who had achieved six or more years of education, AD8 scores were not significantly different between groups and could not differentiate between the non-dementia and patients with dementia in the receiver-operator characteristics curve analysis. In contrast, in those participants who had received less than six years of education, the AD8 scores significantly differentiated between non-dementia and patients with dementia (p = 0.03).

CONCLUSIONS

There was a low rate of attendance at a specialist memory clinic following referral after the AD8 interview. Higher levels of education facilitated individuals to make a decision to accept the recommended referral appointment, while the AD8 showed a higher rate of differentiation between individuals who had received an education of less than six years.

Risk of dementia after charcoal-burning suicide attempts: a nationwide cohort study in Taiwan

This study aimed to investigate the association between charcoal-burning suicide attempts and the risk of developing dementia. A nationwide, matched cohort, population-based study enrolled a total of 4103 patients with newly diagnosed charcoal-burning suicide attempts, between 2000 and 2010, which were selected from the National Health Insurance Research Database of Taiwan, along with 12,309 controls matched for sex and age. After adjusting for confounding factors, Fine and Gray's competing risk analysis was used to compare the risk of developing dementia during the 10-year follow-up period. Of the enrolled patients (n=16,412), dementia developed in 303 (1.85%), including 2.56% in the study group (105 in 4103) and 1.61% (198 in 12,309) in the control group. The Fine and Gray's survival analysis revealed that the patients with charcoal-burning suicide attempts were likely to develop dementia, with a crude HR of 5.170 (95% CI 4.022 to 6.644, p<0.001). After adjusting for age, sex, comorbidity, geographic area and urbanization level of residence, and monthly insured premium, the adjusted HR was 4.220 (95% CI 3.188 to 5.586, p<0.001). Suicide attempts were associated with an increased risk of degenerative dementia in this study. Patients with charcoal-burning suicide attempts had a fourfold risk of dementia than the control group.

Anti-herpetic Medications and Reduced Risk of Dementia in Patients with Herpes Simplex Virus Infections-a Nationwide, Population-Based Cohort Study in Taiwan

This retrospective cohort study is to investigate the association between herpes simplex virus (HSV) infections and dementia, and the effects of anti-herpetic medications on the risk involved, using Taiwan's National Health Insurance Research Database (NHIRD). We enrolled a total of 33,448 subjects, and identified 8362 with newly diagnosed HSV infections and 25,086 randomly selected sex- and age-matched controls without HSV infections in a ratio of 1:3, selected from January 1, to December 31, 2000. A multivariable Cox proportional hazards regression model was used to evaluate the risk of developing dementia in the HSV cohort. This analysis revealed an adjusted hazard ratio of 2.564 (95% CI: 2.351-2.795, P < 0.001) for the development of dementia in the HSV-infected cohort relative to the non-HSV cohort. Thus, patients with HSV infections may have a 2.56-fold increased risk of developing dementia. A risk reduction of dementia development in patients affected by HSV infections was found upon treatment with anti-herpetic medications (adjusted HR = 0.092 [95% CI 0.079-0.108], P < 0.001). The usage of anti-herpetic medications in the treatment of HSV infections was associated with a decreased risk of dementia. These findings could be a signal to clinicians caring for patients with HSV infections. Further research is, therefore, necessary to explore the underlying mechanism(s) of these associations.

The Role of Gene Editing in Neurodegenerative Diseases

Neurodegenerative diseases (NDs), at least including Alzheimer's, Huntington's, and Parkinson's diseases, have become the most dreaded maladies because there are no precise diagnostic tools or definite treatments for these debilitating diseases. The increased prevalence and a substantial impact on the social-economic and medical care of NDs propel governments to develop policies to counteract the impact. Although the etiologies of NDs are still unknown, growing evidence suggests that genetic, cellular, and circuit alternations may cause the generation of abnormal misfolded proteins, which uncontrolledly accumulate to damage and eventually overwhelm the protein-disposal mechanisms of these neurons, leading to a common pathological feature of NDs. If the functions and the connectivity can be restored, alterations and accumulated damages may improve. The gene-editing tools including zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats-associated nucleases (CRISPR/CAS) have emerged as a novel tool not only for generating specific ND animal models for interrogating the mechanisms and screening potential drugs against NDs but also for the editing sequence-specific genes to help patients with NDs to regain function and connectivity. This review introduces the clinical manifestations of three distinct NDs and the applications of the gene-editing technology on these debilitating diseases.

Plasma Aβ analysis using magnetically-labeled immunoassays and PET 18F-florbetapir binding in non-demented patients with major depressive disorder

An increased level of brain amyloid deposition and a decreased level of cerebral spinal fluid (CSF) Aβ42 are currently considered reliable biomarkers of Alzheimer’s disease (AD); however, the usefulness of plasma Aβ levels are not well-established. This study investigated the relationships between plasma Aβ levels and cerebral amyloidosis in 36 non-demented patients with major depressive disorder (MDD). All participants underwent ¹⁸F-florbetapir PET imaging and provided a blood sample at the same time for immunomagnetic reduction assay to measure the plasma levels of Aβ40 and Aβ42. We found inverse associations of the plasma Aβ42 level and the Aβ42/Aβ40 ratio, and a positive association of the plasma Aβ40 level, with cerebral amyloid deposition in the precuneus, parietal and posterior cingulate cortex. Subgroup analyses in subjects with higher ¹⁸F-florbetapir uptake values or MDD with amnestic mild cognitive impairment revealed more pervasive relationships of plasma Aβ measures with ¹⁸F-florbetapir binding across the brain regions examined. The study suggested that regional brain amyloid deposition in terms of ¹⁸F-florbetapir PET uptake had weak-to-moderate associations with plasma Aβ42 and Aβ40 levels, and the Aβ42/Aβ40 ratio. Validation in a larger population of subjects of known cerebral amyloidosis status is needed. Careful interpretation of plasma data is warranted.

Magnesium oxide use and reduced risk of dementia: a retrospective, nationwide cohort study in Taiwan

OBJECTIVE

Dietary magnesium may be associated with a lower risk of dementia; however, the impact of magnesium oxide (MgO), a common laxative, on dementia has yet to be elucidated. This study aimed to investigate the association between the usage of MgO and the risk of developing dementia.

METHODS

We used a dataset from the National Health Research Institute Database (NHRID) of Taiwan containing one million randomly sampled subjects to identify patients aged ≥50 years with no history of MgO usage. A total of 1547 patients who had used MgO were enrolled, along with 4641 controls who had not used the MgO propensity score matched by age, gender and comorbidity, at a ratio of 1:3. After adjusting for confounding risk factors, a Cox proportional hazards model was used to compare the risk of developing dementia during a 10 year follow-up period.

RESULTS

Of the enrolled patients, 44 (2.84%) developed dementia, when compared to 199 (4.28%) in the control group. The Cox proportional hazards regression analysis revealed that the patients who had used MgO were less likely to develop dementia with a crude hazard ratio of 0.617 (95% CI, 0.445-0.856, p = .004). After adjusting for age, gender, comorbidity, geographical area and urbanization level of residence, and monthly income, the adjusted hazard ratio was 0.517 (95% CI, 0.412-0.793, p = .001).

CONCLUSIONS

The patients who used MgO had a decreased risk of developing dementia. Further studies on the effects of MgO in reducing the risk of dementia are therefore warranted.

Increased risk of dementia following herpes zoster ophthalmicus

This retrospective cohort study aimed to examine the relationship between herpes zoster ophthalmicus (HZO) and the subsequent risk of dementia using a population-based database. We retrieved the study sample from the Taiwan Longitudinal Health Insurance Database 2005. The study group included 846 patients with HZO, and the comparison group included 2538 patients without HZO. Each patient was individually followed for a 5-year period to identify those patients who subsequently received a diagnosis of dementia. We performed a Cox proportional hazards regression to calculate the hazard ratios (HRs) along with 95% confidence intervals (CIs) for dementia during the follow-up period between patients with HZO and comparison patients. The respective incidence rates of dementia per 1000 person-years were 10.15 (95% CI: 7.22~13.87) and 3.61 (95% CI: 2.61~4.89) for patients with HZO and comparison patients. The Cox proportional analysis showed that the crude HR of dementia during the 5-year follow-up period was 2.83 (95% CI: 1.83–4.37) for patients with HZO than comparison patients. After adjusting for patients’ characteristics and comorbidities, HZO patients were still at a 2.97-fold greater risk than comparison patients for developing dementia. Furthermore, we found that of sampled male patients, the crude HR of dementia for patients with HZO was as high as 3.35 (95% CI = 1.79–6.28) compared to comparison patients. This study demonstrated an association between HZO and dementia. Clinicians must be alert to suspect dementia in patients with cognitive impairment who had prior HZO.

Cognitive enhancers associated with decreased risk of injury in patients with dementia: a nationwide cohort study in Taiwan

This study aimed to investigate the associations among dementia, psychotropic medications and the risk of overall injuries. In this nationwide matched cohort study, a total of 144 008 enrolled patients ≥age of 50, with 36 002 study subjects who suffered from dementia and 108 006 controls matched for sex and age, from the Inpatient Dataset, for the period 2000-2010 in Taiwan were selected from the National Health Insurance Research Database, according to International Classification of Diseases, 9th Revision, Clinical Modification. When adjusting for the confounding factors, a Cox proportional hazards analysis was used to compare the risk of developing psychiatric disorders during the 10 years of follow-up. Of the study subjects, 6701 (18.61%) suffered injury when compared with 20 919 (19.37%) in the control group. The Cox regression analysis revealed that the study subjects were more likely to develop an injury (HR: 2.294, 95% CI=2.229 to 2.361, P<0.001) after adjusting for sex, age, monthly income, urbanization level, geographic region, and comorbidities. Psychotropic medications in the subjects with dementia were associated with the risk of injury (adjusted HR=0.217, 95% CI: 0.206 to 0.228, P<0.001). Cognitive enhancers, including acetylcholinesterase inhibitors and memantine, were associated with the risk of injury in the study subjects after being adjusted for all comorbidities and medications (adjusted HR=0.712(95% CI=0.512 to 0.925, P<0.01)). In conclusion, patients who suffered dementia had a higher risk of developing injury, and the cognitive enhancers were associated with the decreased risk of injury.

Higher level of circulating estradiol is associated with lower frequency of cognitive impairment in Southeast China

BACKGROUND

Estrogen has been proved to have positive effects on the brain cognitive function. However, many clinical studies investigating the associations between cognitive functions and circulating estrogen levels in perimenopausal and postmenopausal women demonstrated controversial results.

METHOD

Circulating estradiol and follicle stimulating hormone (FSH) levels were obtained from 199 perimenopausal and postmenopausal women (mean age: 49.61 years). The cognitive function has been assessed using the Beijing version of the Montreal Cognitive Assessment.

RESULTS

Results revealed that higher estradiol levels were associated with better cognitive function (p < 0.05) both in perimenopausal and postmenopausal women and levels of FSH were unrelated to cognitive performance.

CONCLUSIONS

In perimenopausal and postmenopausal women, higher levels of circulating estradiol are associated with lower risk of cognitive impairment.

Association between chronic periodontitis and the risk of Alzheimer's disease: a retrospective, population-based, matched-cohort study

Background

Although recent short-term cross-sectional studies have revealed that chronic periodontitis (CP) may be a risk factor for increased cognitive impairment in patients with Alzheimer’s disease (AD), systematic reviews and long-term longitudinal studies have provided less clear evidence regarding the relationship between CP and AD. Therefore, we conducted a retrospective cohort study using the National Health Insurance Research Database (NHIRD) of Taiwan to determine whether patients with CP are at increased risk of developing AD.

Methods

We conducted a retrospective matched-cohort study using the NHIRD of Taiwan. We identified 9291 patients newly diagnosed with CP between 1997 and 2004. A total of 18,672 patients without CP were matched to the patient cohort according to sex, age, index year, co-morbidity and urbanisation level. Cox proportional hazards regression analyses were performed to evaluate the subsequent risk of AD.

Results

Patients with CP had a higher prevalence of hyperlipidaemia, depression, traumatic brain injury and co-morbidities, as well as higher urbanisation levels, than those in the unexposed cohort (all p < 0.01). At the final follow-up, totals of 115 (1.24%) and 208 (1.11%) individuals in the CP exposed and unexposed groups, respectively, had developed AD. Patients with 10 years of CP exposure exhibited a higher risk of developing AD than unexposed groups (adjusted HR 1.707, 95% CI 1.152–2.528, p = 0.0077).

Conclusions

Our findings demonstrate that 10-year CP exposure was associated with a 1.707-fold increase in the risk of developing AD. These findings highlight the need to prevent progression of periodontal disease and promote healthcare service at the national level.

Utilization of Western medicine and traditional Chinese medicine among patients with Alzheimer's disease in Taiwan: a nationwide population-based study

BACKGROUND AND PURPOSE

Large-scale studies of utilization of medical services among patients with Alzheimer's disease (AD) are lacking. We aimed to investigate the usage of Western medicine and traditional Chinese medicine (TCM) among these patients in Taiwan.

METHODS

We analyzed one million samples from the National Health Insurance Research Database in Taiwan. Patients (n = 1814) newly diagnosed with AD in 2001-2010 were divided into TCM users (n = 528) and non-TCM users (n = 1286).

RESULTS

Compared with non-TCM users, TCM users were younger, had a higher female:male ratio and higher utilization rate of Western medicine. The median interval between diagnosis and the first TCM consultation was 7.92 months. Donepezil and rivastigmine were commonly prescribed medications. Chinese herbal medicine was the most popular treatment among TCM users.

CONCLUSIONS

This study revealed the specific usage patterns of TCM and non-TCM medical services among patients with AD. The information could be used for improving the healthcare of patients with AD.

Factors affecting therapeutic response to Rivastigmine in Alzheimer's disease patients in Taiwan

Rivastigmine has been widely used in mild-to-moderate Alzheimer's disease (AD), but the therapeutic response rate varies from 20 to 60%. A dose-dependent effect has been suggested, but the plasma concentration of rivastigmine and its metabolite, NAP 226-90, were not measured in previous studies. The influencing factors of therapeutic response are complicated and discordant in various studies among different ethnic groups. Hence, we analyzed the therapeutic responses of rivastigmine, measured by neuropsychological assessments, among 63 clinically diagnosed AD patients taking a daily dosage of 6-9 mg in relation to their plasma concentration of rivastigmine and NAP 226-90, apolipoprotein E (APOE) genotype and demographic characteristics. Our reports revealed that 41.3% of recruited AD patients had improvement in cognition, measured by Mini-Mental Status Examination (MMSE), and 63.5% in global status, by Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) score. In cognition, the clinically improving group had a significantly higher rivastigmine concentration [p = 0.049, odds ratio (OR) = 1.029, 95%CI = 1.000-1.058], lower initial MMSE score (p = 0.010, OR = 0.708, 95%CI = 0.546-0.920), and lower initial CDR-SB score (p = 0.003, OR = 0.552, 95%CI = 0.372-0.817). The patients with APOE ε4 allele had worsening cognition (p = 0.037, OR = 3.870, 95%CI = 1.082-13.840). In global status, only higher education (p = 0.043, OR = 1.222, 95%CI = 1.007-1.484) was significantly associated with clinical improvement. In conclusion, high concentrations of rivastigmine may benefit cognitive function of AD patients, especially in APOE ε4 (-) carriers.

Everyday cognition scales are related to cognitive function in the early stage of probable Alzheimer's disease and FDG-PET findings

We applied the Everyday Cognition (ECog) scale in normal aging adults and patients with Alzheimer’s disease (AD) to investigate associations between neuropsychological tests and neuroimaging markers. A total of 160 normal aging adults and 40 patients with the early stage of probable AD were included. Neuropsychological performance was assessed using the Consortium to Establish a Registry for Alzheimer’s Disease Neuropsychological Assessment Battery (CERAD-NAB). ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) scans were used to measure AD-related hypometabolism. Nonparametric Spearman correlation analysis was used to study associations between ECog and z-transformed total CERAD-NAB scores in both groups. The results revealed a significant correlation between total ECog and CERAD-NAB scores (rho = −0.28, p < 0.01), and category verbal fluency test with the executive domain of the ECog scale (rho = −0.20, p < 0.01). The CERAD-NAB scores were also significantly correlated with AD-related hypometabolism (rho = −0.49, p < 0.01). The memory domain of the ECog scale was significantly correlated with FDG uptake in the angular gyrus and posterior cingulum gyrus (rho = −0.41 and −0.46, P < 0.01). In conclusion, both total and memory domain ECog scores were correlated with the neuropsychological tests and neuroimaging biomarkers.

Metabolic Activity Value in the Posterior Cingulate Cortex Using F-18 Fluorodeoxyglucose Positron Emission Tomography Brain to Predict the Severity of Alzheimer's

Alzheimer's disease (AD) is a type of dementia which is known as one of a major problem in elderly. Clinicians commonly use mini-mental state examination (MMSE) score to determine the severity of cognitive decline, but MMSE has some limitations such as more subjective, influenced by age, educational degree, and local culture. F-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET) can be used to assess the process of glucose metabolism in posterior cingulate cortex (PCC) area which endures a central role in supporting cognitive function directly. The purpose of this study is to observe a correlation between metabolic activity value of PCC and MMSE score in predicting the severity of AD. A cross-sectional study was done to 30 subjects suspect AD disease with aged 60 years and older. Characteristic data including gender, age, and education, MMSE scoring by psychiatrist, and imaging of F-18 FDG PET were established. The results of correlation test between the value of FDG metabolic activity and MMSE score shows that the value of metabolic activity in the PCC area tends to increase along with the increase of MMSE score (rs = 0.411, P = 0.024). While from the results of multiple regression test with predictor variable consisting of F-18 FDG metabolic activity in the PCC, gender, age, education level, and the interaction between the metabolic activity of F-18 FDG at PCC and gender, a regression model was obtained. There is a significant correlation observed between the captured of F-18 FDG radioactivity with MMSE score in PCC area which can be used as a tool to predict the severity of AD.

Trends, correlates, and disease patterns of antipsychotic use among elderly persons in Taiwan

INTRODUCTION

We used the population-based database to investigate the trends, correlates, and disease patterns of antipsychotic use among elderly people in Taiwan.

METHODS

The National Health Research Institutes provided a database of 1,000,000 random subjects for health service studies. We analyzed a sample of subjects over the age of 65 years from 1997 to 2005. The trends in and factors associated with antipsychotic use were detected. We also examined the proportions of antipsychotics used for psychiatric and medical disorders.

RESULTS

The 1-year prevalence of antipsychotic use in elderly persons increased from 9.8% in 1997 to 12.8% in 2005. The prevalence of first-generation antipsychotic (FGA) use increased from 9.8% to 11.6%, and the prevalence of second-generation antipsychotic (SGA) use increased greatly from 0.01% to 2.02%. Higher prevalence of both FGAs and SGAs were associated with age and higher Charlson Comorbidity Index scores. Psychiatric disorders were commonly found in SGA users (80.8%), whereas only 19.3% of the FGA users had psychiatric disorders. Among the major psychiatric disorders, greater proportions of antipsychotic use were for senile and presenile organic psychotic conditions, other organic psychotic conditions, and affective psychoses. FGAs were much more commonly prescribed for nonpsychiatric disorders, including diseases of symptoms, signs, and ill-defined conditions, the digestive system, and the respiratory system.

DISCUSSION

The prevalence of antipsychotic use, particularly the use of SGAs, increased greatly from 1997 to 2005 among elderly persons in Taiwan. SGAs were most used by subjects with psychiatric disorders, and FGAs were most used by those with nonpsychiatric disorders.

Are Chronic Periodontitis and Gingivitis Associated with Dementia? A Nationwide, Retrospective, Matched-Cohort Study in Taiwan

BACKGROUND

Chronic periodontitis and gingivitis are associated with various diseases; however, their impact on dementia is yet to be elucidated. This study is aimed at investigating the association between chronic periodontitis and gingivitis, and the risk of developing dementia.

METHODS

A total of 2,207 patients, with newly diagnosed chronic periodontitis and gingivitis between January 1, 2000 and December 31, 2000, were selected from the National Health Insurance Research Database of Taiwan, along with 6,621 controls matched for sex and age. After adjusting for confounding factors, Cox proportional hazards analysis was used to compare the risk of developing dementia during the 10-year follow-up period.

RESULTS

Of the study subjects, 25 (1.13%) developed dementia compared to 61 (0.92%) in the control group. Cox proportional hazards regression analysis revealed that the study subjects were more likely to develop dementia (hazard ratio (HR) 2.085, 95% CI 1.552-4.156, p < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region, and comorbidities, the HR for dementia was 2.54 (95% CI 1.297-3.352, p = 0.002).

CONCLUSIONS

Patients with chronic periodontitis and gingivitis have a higher risk of developing dementia. However, further studies on other large or national data sets are required to support the current findings.

The epidemiology and burden of Alzheimer's disease in Taiwan utilizing data from the National Health Insurance Research Database

Purpose

The objectives of this study were to estimate the incidence, cumulative incidence, and economic burden of Alzheimer’s disease (AD) in Taiwan, using data from the National Health Insurance Research Database (NHIRD).

Materials and methods

This was a retrospective, longitudinal, observational study using data from the Longitudinal Health Insurance Database of the NHIRD. Patients were included in this study if they were 50 years of age or older and their records included a primary or secondary diagnosis of AD. New patients who met inclusion criteria were followed up longitudinally from 2005 to 2010. Costs were calculated for the first year following the diagnosis of AD.

Results

Overall, a higher percentage of women than men were diagnosed with AD (54% vs 46%, respectively). The first AD diagnosis occurred most frequently in the age of 75–84 years. The person-year incidence rate increased from 5.63/1,000 persons (95% CI, 5.32–5.94) in 2005 to 8.17/1,000 persons (95% CI, 7.78–8.57) in 2010. The cumulative incidence rate was 33.54/1,000 persons (95% CI, 32.76–34.33) in 2005–2010. The total mean inflated annual costs per patient in new Taiwan dollars (NT$) in the first year of diagnosis ranged from NT$205,413 (2009) to NT$227,110 (2005), with hospitalization representing the largest component.

Conclusion

AD represents a substantial burden in Taiwan, and based on the observed increase in incidence rate over time, it is likely that this burden will continue to increase. The findings reported here are consistent with previous research. The NHIRD contains extensive real-world information that can be used to conduct research, allowing us to expand our understanding of the incidence, prevalence, and burden of disease in Taiwan.

Cross-cultural study of caregiver burden for Alzheimer's disease in Japan and Taiwan: result from Dementia Research in Kumamoto and Tainan (DeReKaT)

BACKGROUND

Caregiver burden (CB) of Alzheimer's disease (AD) in Taiwan is becoming an urgent social issue as well as that in Japan. The comparison of CB may explain how caregiver feels burden in each country.

METHODS

The participants were 343 outpatients with AD and their caregivers of Japan (n = 230) and Taiwan (n = 113). We assessed the CB using the Japanese and Chinese version of Zarit Caregiver Burden Interview (ZBI). The initial analysis was an exploratory factor analysis for each group to confirm the factor structure of ZBI. Then, the multiple-group structural equation modeling (MG-SEM) was used to assess the measurement invariance of ZBI such as configural, metric, and scalar invariances. Lastly, we compared the latent factor means of the ZBI between Japan and Taiwan.

RESULTS

In both groups, the confirmatory factor analysis extracted 3 factors which were labeled "Impact on caregiver's life", "Embarrassed/anger", and "Dependency". The MG-SEM indicated an acceptable model fit, and established the partial scalar measurement invariance (comparative fit index (CFI) = 0.901, root mean square error of approximation (RMSEA) = 0.066). When we compared the latent factor means, the score of "Impact on caregiver's life" in Taiwanese caregivers was significantly higher than that in Japanese (p = 0.001). However, "Dependency" in Taiwanese caregivers was lower than that in Japanese (p < 0.001).

CONCLUSIONS

Partial measurement invariance allowed comparing the latent factor mean across two countries. The results of comparisons suggested that there may be differences in the way of feeling CB between Japan and Taiwan.

An EEG-Based Fuzzy Probability Model for Early Diagnosis of Alzheimer's Disease

Alzheimer's disease is a degenerative brain disease that results in cardinal memory deterioration and significant cognitive impairments. The early treatment of Alzheimer's disease can significantly reduce deterioration. Early diagnosis is difficult, and early symptoms are frequently overlooked. While much of the literature focuses on disease detection, the use of electroencephalography (EEG) in Alzheimer's diagnosis has received relatively little attention. This study combines the fuzzy and associative Petri net methodologies to develop a model for the effective and objective detection of Alzheimer's disease. Differences in EEG patterns between normal subjects and Alzheimer patients are used to establish prediction criteria for Alzheimer's disease, potentially providing physicians with a reference for early diagnosis, allowing for early action to delay the disease progression.

Mini-Mental State Examination (MMSE) for the detection of dementia in clinically unevaluated people aged 65 and over in community and primary care populations

BACKGROUND

The Mini Mental State Examination (MMSE) is a cognitive test that is commonly used as part of the evaluation for possible dementia.

OBJECTIVES

To determine the diagnostic accuracy of the Mini-Mental State Examination (MMSE) at various cut points for dementia in people aged 65 years and over in community and primary care settings who had not undergone prior testing for dementia.

SEARCH METHODS

We searched the specialised register of the Cochrane Dementia and Cognitive Improvement Group, MEDLINE (OvidSP), EMBASE (OvidSP), PsycINFO (OvidSP), LILACS (BIREME), ALOIS, BIOSIS previews (Thomson Reuters Web of Science), and Web of Science Core Collection, including the Science Citation Index and the Conference Proceedings Citation Index (Thomson Reuters Web of Science). We also searched specialised sources of diagnostic test accuracy studies and reviews: MEDION (Universities of Maastricht and Leuven, www.mediondatabase.nl), DARE (Database of Abstracts of Reviews of Effects, via the Cochrane Library), HTA Database (Health Technology Assessment Database, via the Cochrane Library), and ARIF (University of Birmingham, UK, www.arif.bham.ac.uk). We attempted to locate possibly relevant but unpublished data by contacting researchers in this field. We first performed the searches in November 2012 and then fully updated them in May 2014. We did not apply any language or date restrictions to the electronic searches, and we did not use any methodological filters as a method to restrict the search overall.

SELECTION CRITERIA

We included studies that compared the 11-item (maximum score 30) MMSE test (at any cut point) in people who had not undergone prior testing versus a commonly accepted clinical reference standard for all-cause dementia and subtypes (Alzheimer disease dementia, Lewy body dementia, vascular dementia, frontotemporal dementia). Clinical diagnosis included all-cause (unspecified) dementia, as defined by any version of the Diagnostic and Statistical Manual of Mental Disorders (DSM); International Classification of Diseases (ICD) and the Clinical Dementia Rating.

DATA COLLECTION AND ANALYSIS

At least three authors screened all citations.Two authors handled data extraction and quality assessment. We performed meta-analysis using the hierarchical summary receiver-operator curves (HSROC) method and the bivariate method.

MAIN RESULTS

We retrieved 24,310 citations after removal of duplicates. We reviewed the full text of 317 full-text articles and finally included 70 records, referring to 48 studies, in our synthesis. We were able to perform meta-analysis on 28 studies in the community setting (44 articles) and on 6 studies in primary care (8 articles), but we could not extract usable 2 x 2 data for the remaining 14 community studies, which we did not include in the meta-analysis. All of the studies in the community were in asymptomatic people, whereas two of the six studies in primary care were conducted in people who had symptoms of possible dementia. We judged two studies to be at high risk of bias in the patient selection domain, three studies to be at high risk of bias in the index test domain and nine studies to be at high risk of bias regarding flow and timing. We assessed most studies as being applicable to the review question though we had concerns about selection of participants in six studies and target condition in one study.The accuracy of the MMSE for diagnosing dementia was reported at 18 cut points in the community (MMSE score 10, 14-30 inclusive) and 10 cut points in primary care (MMSE score 17-26 inclusive). The total number of participants in studies included in the meta-analyses ranged from 37 to 2727, median 314 (interquartile range (IQR) 160 to 647). In the community, the pooled accuracy at a cut point of 24 (15 studies) was sensitivity 0.85 (95% confidence interval (CI) 0.74 to 0.92), specificity 0.90 (95% CI 0.82 to 0.95); at a cut point of 25 (10 studies), sensitivity 0.87 (95% CI 0.78 to 0.93), specificity 0.82 (95% CI 0.65 to 0.92); and in seven studies that adjusted accuracy estimates for level of education, sensitivity 0.97 (95% CI 0.83 to 1.00), specificity 0.70 (95% CI 0.50 to 0.85). There was insufficient data to evaluate the accuracy of the MMSE for diagnosing dementia subtypes.We could not estimate summary diagnostic accuracy in primary care due to insufficient data.

AUTHORS' CONCLUSIONS

The MMSE contributes to a diagnosis of dementia in low prevalence settings, but should not be used in isolation to confirm or exclude disease. We recommend that future work evaluates the diagnostic accuracy of tests in the context of the diagnostic pathway experienced by the patient and that investigators report how undergoing the MMSE changes patient-relevant outcomes.

Beta-amyloid deposition and cognitive function in patients with major depressive disorder with different subtypes of mild cognitive impairment: (18)F-florbetapir (AV-45/Amyvid) PET study

PURPOSE

The objective of this study was to evaluate the amyloid burden, as assessed by (18)F-florbetapir (AV-45/Amyvid) positron emission tomography PET, in patients with major depressive disorder (MDD) with different subtypes of mild cognitive impairment (MCI) and the relationship between amyloid burden and cognition in MDD patients.

METHODS

The study included 55 MDD patients without dementia and 21 healthy control subjects (HCs) who were assessed using a comprehensive cognitive test battery and (18)F-florbetapir PET imaging. The standardized uptake value ratios (SUVR) in eight cortical regions using the whole cerebellum as reference region were determined and voxel-wise comparisons between the HC and MDD groups were performed. Vascular risk factors, serum homocysteine level and the apolipoprotein E (ApoE) genotype were also determined.

RESULTS

Among the 55 MDD patients, 22 (40.0 %) had MCI, 12 (21.8 %) non-amnestic MCI (naMCI) and 10 (18.2 %) amnestic MCI (aMCI). The MDD patients with aMCI had the highest relative (18)F-florbetapir uptake in all cortical regions, and a significant difference in relative (18)F-florbetapir uptake was found in the parietal region as compared with that in naMCI subjects (P < 0.05) and HCs (P < 0.01). Voxel-wise analyses revealed significantly increased relative (18)F-florbetapir uptake in the MDD patients with aMCI and naMCI in the frontal, parietal, temporal and occipital areas (P < 0.005). The global cortical SUVR was significantly negatively correlated with MMSE score (r = -0.342, P = 0.010) and memory function (r = -0.328, P = 0.015). The negative correlation between the global SUVR and memory in the MDD patients remained significant in multiple regression analyses that included age, educational level, ApoE genotype, and depression severity (β = -3.607, t = -2.874, P = 0.006).

CONCLUSION

We found preliminary evidence of brain beta-amyloid deposition in MDD patients with different subtypes of MCI. Our findings in MDD patients support the hypothesis that a higher amyloid burden is associated with a poorer memory performance. We also observed a high prevalence of MCI among elderly depressed patients, and depressed patients with MCI exhibited heterogeneously elevated (18)F-florbetapir retention as compared with depressed patients without MCI. The higher amyloid burden in the aMCI patients suggests that these patients may also be more likely to develop Alzheimer's disease than other patients diagnosed with major depression.

Association between caregiver depression and individual behavioral and psychological symptoms of dementia in Taiwanese patients

INTRODUCTION

The aim of this study was to investigate caregiver depression associated with neuropsychiatric symptoms in Taiwanese people.

METHODS

A cross-sectional design was used in this study. Two hundred seventy-six pairs of patients with dementia and their caregivers who visited the memory clinic of a general hospital from July 2001 to October 2008 were recruited. Caregiver depression was evaluated with the Center for Epidemiologic Studies Depression Scale (CES-D); the behavioral and psychological symptoms of dementia were evaluated using the Neuropsychiatric Inventory. Demographic data of the patients and caregivers, including cognitive functions and clinical dementia ratings, were collected. In addition to descriptive statistics, we examined the relationship between each parameter and caregiver depression using Pearson correlation, independent t-test, or analysis of variance.

RESULTS

The results showed a statistically significant positive correlation between the total Neuropsychiatric Inventory score and CES-D score (r = 0.345, P < 0.001) in the bivariate analyses. For individual behavioral and psychological symptoms of dementia, agitation/aggression, anxiety, nighttime behavior disturbances, irritability/lability, and hallucinations were the five leading symptoms significantly associated with caregiver depression (CES-D).

DISCUSSION

Carefully managing these symptoms is likely to reduce depression in dementia caregivers.

The Effects of Anti-Dementia and Nootropic Treatments on the Mortality of Patients with Dementia: A Population-Based Cohort Study in Taiwan

Background

Few studies have examined the contribution of treatment on the mortality of dementia based on a population-based study.

Objective

To investigate the effects of anti-dementia and nootropic treatments on the mortality of dementia using a population-based cohort study.

Methods

12,193 incident dementia patients were found from 2000 to 2010. Their data were compared with 12,193 age- and sex-matched non-dementia controls that were randomly selected from the same database. Dementia was classified into vascular (VaD) and degenerative dementia. Mortality incidence and hazard ratios (HRs) were calculated.

Results

The median survival time was 3.39 years (95% confidence interval [CI]: 2.88–3.79) for VaD without medication, 6.62 years (95% CI: 6.24–7.21) for VaD with nootropics, 3.01 years (95% CI: 2.85–3.21) for degenerative dementia without medication, 8.11 years (95% CI: 6.30–8.55) for degenerative dementia with anti-dementia medication, 6.00 years (95% CI: 5.73–6.17) for degenerative dementia with nootropics, and 9.03 years (95% CI: 8.02–9.87) for degenerative dementia with both anti-dementia and nootropic medications. Compared to the non-dementia group, the HRs among individuals with degenerative dementia were 2.69 (95% CI: 2.55–2.83) without medication, 1.46 (95% CI: 1.39–1.54) with nootropics, 1.05 (95% CI: 0.82–1.34) with anti-dementia medication, and 0.92 (95% CI: 0.80–1.05) with both nootropic and anti-dementia medications. VaD with nootropics had a lower mortality (HR: 1.25, 95% CI: 1.15–1.37) than VaD without medication (HR: 2.46, 95% CI: 2.22–2.72).

Conclusion

Pharmacological treatments have beneficial effects for patients with dementia in prolonging their survival.

Prevalence and risk factors of cognitive impairment in Parkinson disease: a population-based case-control study in Taiwan

The aim of this study was to evaluate the Parkinson disease (PD) prevalence of cognitive impairment in Taiwan.The case-control study consisted of 6177 cognitive impairment patients and 24,708 noncognitive impairment as controls for the period of 2006 to 2010 and both of the groups aged ≥50 years. The multivariable logistic regression analyses were used to estimate the odds ratio (OR) for cognitive impairment, and the 95% confidence intervals (CIs) among patients with PD were compared with those of non-PD patients.PD (adjusted odds ratio [aOR] is 3.07, 95% CI 2.76-3.41) is the one of the most contributed risk factors for cognitive impairment. Besides, we found a remarkable result of the diagnosed cognitive impairment of PD that was found highest in the first 6 months (aOR 11.98, 95% CI 8.51-16.86) and then decrease the incident year by year. The PD prevalence in a patient with cognitive impairment in our data present is 12.1% lower than those with truly dementia published previously and documented by western studies.We found a remarkable result of the diagnosed cognitive impairment of PD that was found highest in the first 6 months and then decrease the incident year by year.

Screening dementia in the outpatient department: patients at risk for dementia

The targeted screening for individuals at the risks of having dementia would be crucial to the further public health issues for dementia. This study aimed to conduct a screening study in an outpatient department of a regional hospital to screen people who were at risk of developing comorbid dementia. Patients who visited Kaohsiung Municipal Ta-Tung Hospital (KMTTH) clinics during the period from June 1, 2013, to May 31, 2014, were invited to participate in this screening voluntarily. The trained interviewer collected all participants' demographic characteristics and used the instrument of ascertainment of dementia 8 (AD8) to find out suspected dementia ones. The result showed a higher ratio (24.1%) of suspected dementia in the outpatient department of a hospital, 500 out of 2017 subjects, than that in the general population. The median (interquartile range) age was significantly higher in the suspected dementia participants (70, (62, 77)) compared to that in nonsuspected dementia ones (65, (60, 73)), and the probability of suspected dementia was significantly increasing with age (P < 0.001). Instead of screening dementia in general population, screening people at the risk of dementia could be the practicable and important issues in the care of dementia.

Increased brain amyloid deposition in patients with a lifetime history of major depression: evidenced on 18F-florbetapir (AV-45/Amyvid) positron emission tomography

PURPOSE

The literature suggests that a history of depression is associated with an increased risk of developing Alzheimer's disease (AD). The aim of this study was to examine brain amyloid accumulation in patients with lifetime major depression using (18)F-florbetapir (AV-45/Amyvid) PET imaging in comparison with that in nondepressed subjects.

METHODS

The study groups comprised 25 depressed patients and 11 comparison subjects who did not meet the diagnostic criteria for AD or amnestic mild cognitive impairment. Vascular risk factors, homocysteine and apolipoprotein E (ApoE) genotype were also examined. The standard uptake value ratio (SUVR) of each volume of interest was analysed using whole the cerebellum as the reference region.

RESULTS

Patients with a lifetime history of major depression had higher (18)F-florbetapir SUVRs in the precuneus (1.06 ± 0.08 vs. 1.00 ± 0.06, p = 0.045) and parietal region (1.05 ± 0.08 vs. 0.98 ± 0.07, p = 0.038) than the comparison subjects. Voxel-wise analysis revealed a significantly increased SUVR in depressed patients in the frontal, parietal, temporal and occipital areas (p < 0.01). There were no significant associations between global (18)F-florbetapir SUVRs and prior depression episodes, age at onset of depression, or time since onset of first depression.

CONCLUSION

Increased (18)F-florbetapir binding values were found in patients with late-life major depression relative to comparison subjects in specific brain regions, despite no differences in age, sex, education, Mini Mental Status Examination score, vascular risk factor score, homocysteine and ApoE ε4 genotype between the two groups. A longitudinal follow-up study with a large sample size would be worthwhile.

Epidemiologic studies of modifiable factors associated with cognition and dementia: systematic review and meta-analysis

Background

Cognitive impairment, including dementia, is a major health concern with the increasing aging population. Preventive measures to delay cognitive decline are of utmost importance. Alzheimer’s disease (AD) is the most frequent cause of dementia, increasing in prevalence from <1% below the age of 60 years to >40% above 85 years of age.

Methods

We systematically reviewed selected modifiable factors such as education, smoking, alcohol, physical activity, caffeine, antioxidants, homocysteine (Hcy), n-3 fatty acids that were studied in relation to various cognitive health outcomes, including incident AD. We searched MEDLINE for published literature (January 1990 through October 2012), including cross-sectional and cohort studies (sample sizes > 300). Analyses compared study finding consistency across factors, study designs and study-level characteristics. Selecting studies of incident AD, our meta-analysis estimated pooled risk ratios (RR), population attributable risk percent (PAR%) and assessed publication bias.

Results

In total, 247 studies were retrieved for systematic review. Consistency analysis for each risk factor suggested positive findings ranging from ~38.9% for caffeine to ~89% for physical activity. Education also had a significantly higher propensity for “a positive finding” compared to caffeine, smoking and antioxidant-related studies. Meta-analysis of 31 studies with incident AD yielded pooled RR for low education (RR = 1.99; 95% CI: 1.30-3.04), high Hcy (RR = 1.93; 95% CI: 1.50-2.49), and current/ever smoking status (RR = 1.37; 95% CI: 1.23-1.52) while indicating protective effects of higher physical activity and n-3 fatty acids. Estimated PAR% were particularly high for physical activity (PAR% = 31.9; 95% CI: 22.7-41.2) and smoking (PAR%=31.09%; 95% CI: 17.9-44.3). Overall, no significant publication bias was found.

Conclusions

Higher Hcy levels, lower educational attainment, and decreased physical activity were particularly strong predictors of incident AD. Further studies are needed to support other potential modifiable protective factors, such as caffeine.

A walk-in screening of dementia in the general population in Taiwan

Alzheimer's disease (AD) has increased in its prevalence due to the increasing aged population. Currently there is no updated data on the prevalence of dementia including its very mild stage in Taiwan. Under the extensive coverage of Mentality Protection Center (MPC), Fo Guang Shan, Taiwan, the volunteers of MPC have conducted the medicine-related services and the screening of dementia by AD8 (ascertainment of dementia 8) that can screen the dementia even at its very mild stage in general population in all Taiwan. From 2011 to 2013, in total, 2,171 participants, 368 in the northern, 549 in the central, 877 in the southern, and 377 in the eastern part, were recruited with the mean age being 66.9 ± 10.2 years old. The ratio of suspected dementia patients, AD8 score greater than or equal to 2, was 13.6% of all recruited participants with their mean AD8 score being 2.9 ± 1.3, mean age being 69.4 ± 10.8 years old, and female predominance being 73.0%. Although this is a screening study, it has extensive coverage of all Taiwan and the use of AD8 is capable of screening very mild dementia. A further study with a randomized sampling to examine the prevalence and incidence of dementia including its very mild stage is encouraged.

Direct medical costs in patients with Alzheimer's disease in Taiwan: A population-based study

BACKGROUND

Alzheimer's disease (AD) has the potential to become a major health concern and associated health care costs may become a significant economic burden on society.

OBJECTIVE

The aim of this study was to estimate the direct medical costs attributable to AD in patients aged ≥60 years in Taiwan from 2000 through 2002 and to explore the correlation of these costs with patients' age and sex.

METHODS

This study was based on the National Health Insurance Research Database of Taiwan's National Health Insurance (NHI) program. The NHI program insures >98% of the 23 million inhabitants of Taiwan. Detailed data were extracted from a random sample of 0.2% of inpatient and 5% of outpatient recipients with AD (International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code 331.0) who were aged ≥60 years and who received inpatient or outpatient services with claims from January 1, 2000, to December 31, 2002. Duplicate charges for a specific patient and diagnoses of other types of dementia were excluded from this study.

RESULTS

A total of 69,780 patients were found to have a diagnosis of AD. The direct medical costs for outpatients were estimated at US $1.2 million in 2000, US $1.9 million in 2001, and US $2.3 million in 2002; the costs for inpatient care were estimated at US $670,000 in 2000, US $2.4 million in 2001, and US $3.2 million in 2002. The total direct medical costs were estimated at US $1.86 million in 2000, US $4.24 million in 2001, and US $5.48 million in 2002. The increase of total direct medical costs was not significantly correlated with patients' age or sex.

CONCLUSIONS

From 2000 through 2002, the direct medical costs of AD increased annually in Taiwan among patients with AD aged ≥60 years. No significant correlation was found between increased total direct medical costs and sex or age. The cost estimate presented here has implications for future decision making about reallocating medical resources for treating AD in Taiwan.

Dementia studies in Chinese populations

Variations in the prevalence of dementia in different ethnic groups have been reported worldwide, and a number of reviews have provided a picture of epidemiological studies in dementia research. However, little is known about epidemiological studies in Chinese populations. In this review, we searched PubMed and the Web of Science for original research articles published in English up to July 2013 on the prevalence, incidence, risk factors, and prognosis of dementia in Chinese populations worldwide. Except for the prevalence, we included only population-based follow-up studies. We identified 25 studies in elderly Chinese residents in Mainland China, Hong Kong, Taiwan, and Singapore, and found a higher prevalence of dementia in Mainland China than in the other locations, which may be due to that the studies from Mainland China are more recent than those from other locations. A notable increase in incidence was observed when dementia cases were diagnosed using 10/66 diagnostic criteria compared to other criteria. Studies on risk factors for dementia were limited and mostly from Mainland China. Age, gender, education, smoking, and alcohol consumption were related to the risk of dementia in Chinese populations. Only two prognostic studies were identified, and age, gender, and residential area were related to the prognosis of dementia. In conclusion, the prevalence, incidence, and risk factors for dementia found in Chinese populations were comparable to other ethnic groups, but no conclusive results on prognosis were found. The differences in prevalence and incidence were influenced by the diagnostic criteria and the time of study. Longitudinal population-based studies on the incidence, risk factors, and prognosis of dementia in Chinese populations are required.