Protective effect of bilingualism on aging, MCI, and dementia: A community-based study.

INTRODUCTION: Lifelong bilingualism is associated with a delayed age at onset of dementia, but evidence from community-based studies is limited. We investigated the relationship between bilingualism and the prevalence of cognitive impairment in a linguistically diverse community. METHODS: A door-to-door community study was conducted from January to December 2021 in urban Bengaluru, India. 1234 individuals aged ≥60 years participated in the study. Participants were diagnosed with no cognitive impairment (NCI), mild cognitive impairment (MCI), or dementia using established diagnostic criteria. RESULTS: Dementia prevalence was higher in monolinguals (4.9%) than bilinguals (0.4%) (P = .001). The prevalence of MCI was also higher in monolinguals (8.5%) than bilinguals (5.3%) (P = .001). The study also revealed better cognitive function in bilinguals than monolinguals with NCI, after controlling for confounding variables. DISCUSSION: The current study provides significant support for the protective effect of bilingualism on cognitive impairment in an urban community with extensive bilingual interactional contexts in everyday life. HIGHLIGHTS: Bilingualism has been demonstrated to protect against dementia and mild cognitive impairment in a linguistically diverse community with extensive code-switching contexts. Bilingual older individuals had superior baseline cognitive performance compared to monolingual older individuals. Bilingualism was found to have an independent effect on general cognition after adjusting for major social determinants of health in the group without cognitive impairment.

The 2022 symposium on dementia and brain aging in low- and middle-income countries: Highlights on research, diagnosis, care, and impact.

Two of every three persons living with dementia reside in low- and middle-income countries (LMICs). The projected increase in global dementia rates is expected to affect LMICs disproportionately. However, the majority of global dementia care costs occur in high-income countries (HICs), with dementia research predominantly focusing on HICs. This imbalance necessitates LMIC-focused research to ensure that characterization of dementia accurately reflects the involvement and specificities of diverse populations. Development of effective preventive, diagnostic, and therapeutic approaches for dementia in LMICs requires targeted, personalized, and harmonized efforts. Our article represents timely discussions at the 2022 Symposium on Dementia and Brain Aging in LMICs that identified the foremost opportunities to advance dementia research, differential diagnosis, use of neuropsychometric tools, awareness, and treatment options. We highlight key topics discussed at the meeting and provide future recommendations to foster a more equitable landscape for dementia prevention, diagnosis, care, policy, and management in LMICs. HIGHLIGHTS: Two-thirds of persons with dementia live in LMICs, yet research and costs are skewed toward HICs. LMICs expect dementia prevalence to more than double, accompanied by socioeconomic disparities. The 2022 Symposium on Dementia in LMICs addressed advances in research, diagnosis, prevention, and policy. The Nairobi Declaration urges global action to enhance dementia outcomes in LMICs.

A call for clinical trial globalization in Alzheimer's disease and related dementia.

BACKGROUND: The burden of Alzheimer's disease and related dementia (ADRD) is projected to disproportionally impact low-middle-income countries (LMICs). However, there is a systematic under-representation of LMICs in ADRD clinical trial platforms. METHODS: We aimed to determine the global distribution of ADRD clinical trials and identify existing barriers for conducting clinical trials in LMICs. Primary data sources to identify trial distribution in LMICs included ClinicalTrials.gov and the International Trials Registry Platform. An additional systematic review and expert consensus interviews were conducted to identify barriers for conducting clinical trials in LMICs. FINDINGS: Among 1237 disease-modifying therapies tested in ADRD clinical trials, only 11.6% have been or are conducted in emerging economies (upper-middle income [9.6%] and low-middle income [2.0%]). We identified several limitations for trial implementation including a lack of financial resources, low industry presence, regulatory obstacles, and operational barriers INTERPRETATION: Although LMICs bear the greatest burden of ADRD globally, substantial development of clinical trial platforms to address this inequity and health disparity is lacking.

Gaps in clinical research in frontotemporal dementia: A call for diversity and disparities-focused research.

Frontotemporal dementia (FTD) is one of the leading causes of dementia before age 65 and often manifests as abnormal behavior (in behavioral variant FTD) or language impairment (in primary progressive aphasia). FTD's exact clinical presentation varies by culture, language, education, social norms, and other socioeconomic factors; current research and clinical practice, however, is mainly based on studies conducted in North America and Western Europe. Changes in diagnostic criteria and procedures as well as new or adapted cognitive tests are likely needed to take into consideration global diversity. This perspective paper by two professional interest areas of the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment examines how increasing global diversity impacts the clinical presentation, screening, assessment, and diagnosis of FTD and its treatment and care. It subsequently provides recommendations to address immediate needs to advance global FTD research and clinical practice.

Cognition, Behavior, and Caregiver Stress in Dementia during the COVID-19 Pandemic: An Indian Perspective.

OBJECTIVES: Little is known regarding the cognitive and behavioral status of patients with dementia and their caregivers in lower middle-income countries during the COVID-19 pandemic. This study aimed to understand the impact of the pandemic on persons with dementia and their caregivers in India. METHODS: This was an observational study. A cohort of 66 persons with dementia and their caregivers were evaluated during the COVID-19 pandemic in 2 specialist hospitals in South India. Caregivers were interviewed at 2 distinct time points of the pandemic: during the national lockdown and 5 months after during later periods of the "cluster of cases" transmission phase. Participants were assessed via telephone utilizing validated instruments (Neuropsychiatric Inventory [NPI], Clinical Dementia Rating [CDR] Scale, and Depression, Anxiety and Stress Scale [DASS-21]) and a semi-structured questionnaire. The questionnaire documented sociodemographic information, clinical history, infection measures adopted, changes in caregiving routines, involvement in functional rehabilitation activities, and access to medical and long-term care support services. RESULTS: The 2-phase follow-up study found a significant worsening of behavior in dementia patients, demonstrated by a difference in the NPI sub-domain scores for anxiety (mean difference [standard deviation, SD] = -0.552 [1.993], t58 = -2.109, p = 0.039) and eating disturbances (mean difference [SD] = -1.121 [2.493], t59 = -3.424, p = 0.001). A relatively high proportion of patients developed anxiety (cumulative incidence = 24.53%) and eating disturbances (cumulative incidence = 26.92%), without having these symptoms at baseline. There was a trend toward an increase in proportion of persons with severe dementia (19.7% vs. 39.4%) on follow-up. Caregiver distress reported was significantly associated with neuropsychiatric symptoms (r = 0.712, p < 0.001) and dementia severity (ρ = 0.365, p = 0.004). In addition, difficulties in accessing medical care persisted between the 2 assessments, and there were statistically significant differences between functional rehabilitation activities such as indoor activities (p < 0.001), outdoor activities (p = 0.013), and physical exercises (p = 0.003) between baseline and follow-up. CONCLUSION: Findings suggest interruption of functional rehabilitation activities and disruption in medical care services are likely to have had an adverse impact on patients with dementia and contributed toward caregiver distress.

Novel TBK1 variant associated with Frontotemporal Dementia overlap syndrome.

BACKGROUND: Recently, TANK binding kinase 1 (TBK1) mutation has been reported as a causative gene for overlap frontotemporal dementia (FTD)-amyotrophic lateral sclerosis (ALS) syndrome. However, there are no reports from families of South Asian ethnicity. OBJECTIVE: To report a case study of a family with the proband having overlap FTD-ALS syndrome caused by a novel TBK1 variant. MATERIALS AND METHODS: Clinical, brain imaging, genetic analysis and laboratory data of the patient with FTD-ALS were performed. In addition, family-based segregation analysis of identified novel variants was also done. RESULTS: This study pertains to genetic analysis in 11 members in a family with only one member affected with overlap FTD-ALS syndrome. The whole-exome sequencing analysis in the symptomatic member showed a novel loss-of-function (LoF) variant c.1810G>T(p.E604X) in the TBK1 gene. Neuroimaging showed a pattern of asymmetric frontotemporal atrophy and hypometabolism. Segregation analysis of the variation demonstrated its presence in several family members, although none of the other members was symptomatic. Further, we observed another missense variation in the NEFH gene (p.Pro683Leu) which was seen in the symptomatic and two asymptomatic family members, the pathogenicity of which is unclear. CONCLUSION: This is the first study of a rare novel TBK1 variant associated with FTD-ALS from India. Asymptomatic family members with the variant have important clinical implications and necessitate the genetic evaluation and long-term follow-up of family members of patients detected with TBK1 mutations. Therefore, although infrequent, genetic screening for the TBK1 gene should be considered when encountering overlap FTD syndromes.

MoCA in five Indian languages: A brief screening tool to diagnose dementia and MCI in a linguistically diverse setting.

INTRODUCTION AND OBJECTIVES: Early dementia diagnosis in low and middle-income countries (LMIC) is challenging due to limited availability of brief, culturally appropriate, and psychometrically validated tests. Montreal Cognitive Assessment (MoCA) is one of the most widely used cognitive screening tests in primary and secondary care globally. In the current study, we adapted and validated MoCA in five Indian languages (Hindi, Bengali, Telugu, Kannada, and Malayalam) and determined the optimal cut-off points that correspond to screening for clinical diagnosis of dementia and MCI. METHODS: A systematic process of adaptation and modifications of MoCA was fulfilled. A total of 446 participants: 214 controls, 102 dementia, and 130 MCI were recruited across six centers. RESULTS: Across five languages, the area under the curve for diagnosis of dementia varied from 0.89 to 0.98 and MCI varied from 0.73 to 0.96. The sensitivity, specificity and optimum cut-off scores were established separately for five Indian languages. CONCLUSIONS: The Indian adapted MoCA is standardized and validated in five Indian languages for early diagnosis of dementia and MCI in a linguistically and culturally diverse population.

Semantic memory impairment in dementia: A cross-cultural adaptation study.

BACKGROUND: Semantic memory deficits are frequently encountered in dementia and distinct patterns of semantic impairment characterize the subtypes of dementia. Life course and cultural experiences significantly influence semantic memory. Hence, there is a need to assess semantic memory using culturally appropriate tests, to aid accurate diagnosis of dementia and facilitate cross-cultural collaborative research. AIMS: In this prospective study, we adapted and validated the Cambridge Semantic Memory (CSM) test battery to the Indian cultural context and studied the patterns of semantic memory impairment across dementia subtypes. METHODS: The CSM battery was modified using standard methods and by incorporating culturally appropriate changes and new semantic categories relevant to India. The adapted Indian Semantic Memory (ISM) test battery was administered to a cohort of 121 subjects, consisting of controls and dementia: Alzheimer's disease (AD), progressive non-fluent aphasia (PNFA), semantic dementia (SD), and behavioral variant fronto-temporal dementia (BvFTD). Profile of semantic memory performance across groups was examined. RESULTS: The ISM battery was found to be a valid measure of semantic memory. The novel semantic categories of gods/religious icons, vegetables, and food items added value to the diagnostic process. Distinct semantic memory profiles in SD, PNFA, AD, and BvFTD were demonstrated. CONCLUSIONS: The cultural adaptation of a semantic memory battery for the Indian context provided sensitive evidence of semantic memory impairment in dementia and its subtypes. The clinical and research application of the ISM battery will enhance diagnostic evaluation that can aid in early and accurate identification of deficits and devising intervention strategies and enable research across cultures.

Picture-naming test for a linguistically diverse population with cognitive impairment and dementia.

BACKGROUND: Picture-naming tests (PNTs) evaluate linguistic impairment in dementia due to semantic memory impairment, impaired lexical retrieval or perceptual deficits. They also assess the decline in naming impairment at various stages of dementia and mild cognitive impairment (MCI) that occurs due to progressive cognitive impairment. With the increasing numbers of people with dementia globally, it is necessary to have validated naming tests and norms that are culturally and linguistically appropriate. AIMS: In this cross-sectional study we harmonized a set of 30 images applicable to the Indian context across five languages and investigated the picture-naming performance in patients with MCI and dementia. METHODS & PROCEDURES: A multidisciplinary expert group formed by the Indian Council of Medical Research (ICMR) collaborated towards developing and adapting a picture naming test (PNT) known as the ICMR-PNT in five Indian languages: Hindi, Bengali, Telugu, Kannada and Malayalam. Based on cross-cultural adaptation guidelines and item-wise factor analysis and correlations established separately across five languages, the final version of the ICMR-PNT test was developed. A total of 368 controls, 123 dementia and 128 MCI patients were recruited for the study. Psychometric properties of the adapted version of the ICMR-PNT were examined, and sensitivity and specificity were examined. OUTCOMES & RESULTS: The ICMR-PNT scores in all languages combined were higher in controls compared with patients with dementia and MCI (F2, 615 = 139.85; p < 0.001). Furthermore, PNT scores for MCI was higher in comparison with patients with dementia in all languages combined (p < 0.001). The area under the curve across the five languages ranged from 0.81 to 1.00 for detecting dementia. There was a negative correlation between Clinical Dementia Rating (CDR) and ICMR-PNT scores and a positive correlation between Addenbrooke's Cognitive Examination-III (ACE-III) and ICMR-PNT scores in control and patient groups. CONCLUSIONS & IMPLICATIONS: The ICMR-PNT was developed by following cross-cultural adaptation guidelines and establishing correlations using item-wise factor analysis across five languages. This adapted PNT was found to be a reliable tool when assessing naming abilities effectively in mild to moderate dementia in a linguistically diverse context. WHAT THIS PAPER ADDS: What is already known on this subject Picture-naming evaluates language impairment linked to naming difficulties due to semantic memory, lexical retrieval or perceptual disturbances. As a result, picture naming tests (PNTs) play an important role in the diagnosis of dementia. In a heterogeneous population such as India, there is a need for a common PNT that can be used across the wide range of languages. What this study adds to existing knowledge PNTs such as the Boston Naming Test (BNT) were developed for the educated, mostly English-speaking, Western populations and are not appropriate for use in an Indian context. To overcome this challenge, a PNT was harmonized in five Indian languages (Hindi, Bengali, Telugu, Kannada and Malayalam) and we report the patterns of naming difficulty in patients with MCI and dementia. The ICMR-PNT demonstrated good diagnostic accuracy when distinguishing patients with mild to moderate dementia from cognitively normal individuals. What are the potential or actual clinical implications of this work? With the growing number of persons suffering from Alzheimer's disease and other forms of dementia around the world, its critical to have culturally and linguistically relevant naming tests and diagnosis. This validated ICMR-PNT can be used widely as a clinical tool to diagnose dementia and harmonize research efforts across diverse populations.

Role of Autoantibodies in Neurodegenerative Dementia: An Emerging Association.

OBJECTIVE: In the background of an emerging role for immune dysregulation in neurodegenerative dementias, this study aimed to investigate the relationship between systemic autoimmunity and dementia. The objective was to study the frequency and profile of disease-specific autoantibodies in Alzheimer's dementia (AD), frontotemporal dementia (FTD), and dementia with Lewy bodies (DLB). METHODS: Immunological testing was performed in a large cohort of neurodegenerative dementia diagnosed based on standard clinical and imaging criteria. Patients were evaluated for the presence of autoantibodies specific for systemic autoimmune diseases that included anti-extractable nuclear antibody profile, rheumatoid factor antibody (RA), perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA), and cytoplasmic anti-neutrophil cytoplasmic antibody (c-ANCA) in serum. RESULTS: Of 174 patients with degenerative dementia (FTD = 114, AD = 53, and DLB = 7) evaluated with immunological testing, 18.9% (n = 33) were seropositive for autoantibodies. The common antibodies detected were anti-Scl-70 (25%), anti-Ro-52 (18.7%), anti-nRNP-Sm (12.5%), and anti-CENP-B (9.3%). There were no significant systemic complaints in the majority of patients. A wider range of antibodies were positive in FTD compared to AD and DLB. While no difference was observed in the mean age, sex, or duration of illness between seropositive and negative patients, family history of dementia was more frequent among seronegative patients. CONCLUSION: Our findings indicate an emerging role for immune dysregulation in patients with classical neurodegenerative dementias, especially those with FTD. These autoantibodies could play a role in immune degradation of protein aggregates that characterize neurodegeneration. Study findings emphasize the need to explore the complex relationship between systemic autoimmunity and neurodegenerative dementia.

EEG-based P300 in mesial temporal lobe epilepsy and its correlation with cognitive functions: A case-control study.

OBJECTIVE: P300 is an event-related potential, being explored as an objective tool to assess cognition. This study aimed to investigate the characteristics of auditory and visual P300 in patients with TLE having unilateral HS using electroencephalography (EEG) and to study its correlation with cognition. METHODS: This is a cross-sectional case-control study, where P300 characteristics in thirty patients with unilateral hippocampal sclerosis with refractory epilepsy were compared with fifteen age-, gender-, and years of education-matched healthy controls (M: F-10:5, mean age-28 ±â€¯4.76 years). Among patients, 15 belonged to the right HS group (M: F-9:6, age at onset-12.92 ±â€¯10.22 years, duration of epilepsy-16.67 ±â€¯9.38 years) and 15 to the left HS group (M: F-8:7, age at onset-10.62 ±â€¯7.18 years, duration of epilepsy-15.53 ±â€¯10.14 years). All subjects underwent EEG-based auditory and visual oddball tasks and cognitive assessment. The P300 latencies (in milliseconds) as well as amplitudes (in microvolts) were predicted in EEG and were correlated with cognitive scores. Source localization of P300 was performed with the CLARA algorithm. RESULTS: The auditory P300 latencies in controls, right HS, and left HS were 323.93 ±â€¯40.28, 351.06 ±â€¯47.23, and 328.80 ±â€¯36.03, respectively (p = 0.18) and its amplitudes were 2.3040 ±â€¯1.46, 2.77 ±â€¯1.19, and 2.68 ±â€¯1.78, respectively (p = 0.48). Visual P300 latencies in controls, right HS, and left HS were 365.87 ±â€¯47.37, 359.67 ±â€¯64.45, and 376.00 ±â€¯60.06, respectively (p = 0.51) and its amplitudes were 3.93 ±â€¯2.28, 2.09 ±â€¯1.45, and 3.56 ±â€¯1.74, respectively (p = 0.014). Further, when compared to the control group the cognitive scores were lower in the patient group (p < 0.05). SIGNIFICANCE: In comparison to the controls, patients with right HS recorded lesser amplitude on visual P300 and lower scores on cognitive tests. P300 and cognitive parameters exhibited varied relationship. P300 could be a complementary objective tool to assess cognition in patients with TLE.

Validation of Indian Council of Medical Research Neurocognitive Tool Box in Diagnosis of Mild Cognitive Impairment in India: Lessons from a Harmonization Process in a Linguistically Diverse Society.

BACKGROUND/AIMS: In a linguistically diverse country such as India, challenges remain with regard to diagnosis of early cognitive decline among the elderly, with no prior attempts made to simultaneously validate a comprehensive battery of tests across domains in multiple languages. This study aimed to determine the utility of the Indian Council of Medical Research-Neurocognitive Tool Box (ICMR-NCTB) in the diagnosis of mild cognitive impairment (MCI) and its vascular subtype (VaMCI) in 5 Indian languages. METHODS: Literate subjects from 5 centers across the country were recruited using a uniform process, and all subjects were classified based on clinical evaluations and a gold standard test protocol into normal cognition, MCI, and VaMCI. Following adaptation and harmonization of the ICMR-NCTB across 5 different Indian languages into a composite Z score, its test performance against standards, including sensitivity and specificity of the instrument as well as of its subcomponents in diagnosis of MCI, was evaluated in age and education unmatched and matched groups. RESULTS: Variability in sensitivity-specificity estimates was noted between languages when a total of 991 controls and 205 patients with MCI (157 MCI and 48 VaMCI) were compared due to a significant impact of age, education, and language. Data from a total of 506 controls, 144 patients with MCI, and 46 patients with VaMCI who were age- and education-matched were compared. Post hoc analysis after correction for multiple comparisons revealed better performance in controls relative to all-cause MCI. An optimum composite Z-score of -0.541 achieved a sensitivity of 81.1% and a specificity of 88.8% for diagnosis of all-cause MCI, with a high specificity for diagnosis of VaMCI. Using combinations of multiple-domain 2 test subcomponents retained a sensitivity and specificity of >80% for diagnosis of MCI. CONCLUSIONS: The ICMR-NCTB is a "first of its kind" approach at harmonizing neuropsychological tests across 5 Indian languages for the diagnosis of MCI due to vascular and other etiologies. Utilizing multiple-domain subcomponents also retains the validity of this instrument, making it a valuable tool in MCI research in multilingual settings.

Standardising Dementia Diagnosis Across Linguistic and Educational Diversity: Study Design of the Indian Council of Medical Research-Neurocognitive Tool Box (ICMR-NCTB).

OBJECTIVES: While the burden of dementia is increasing in low- and middle-income countries, there is a low rate of diagnosis and paucity of research in these regions. A major challenge to study dementia is the limited availability of standardised diagnostic tools for use in populations with linguistic and educational diversity. The objectives of the study were to develop a standardised and comprehensive neurocognitive test battery to diagnose dementia and mild cognitive impairment (MCI) due to varied etiologies, across different languages and educational levels in India, to facilitate research efforts in diverse settings. METHODS: A multidisciplinary expert group formed by Indian Council of Medical Research (ICMR) collaborated towards adapting and validating a neurocognitive test battery, that is, the ICMR Neurocognitive Tool Box (ICMR-NCTB) in five Indian languages (Hindi, Bengali, Telugu, Kannada, and Malayalam), for illiterates and literates, to standardise diagnosis of dementia and MCI in India. RESULTS: Following a review of existing international and national efforts at standardising dementia diagnosis, the ICMR-NCTB was developed and adapted to the Indian setting of sociolinguistic diversity. The battery consisted of tests of cognition, behaviour, and functional activities. A uniform protocol for diagnosis of normal cognition, MCI, and dementia due to neurodegenerative diseases and stroke was followed in six centres. A systematic plan for validating the ICMR-NCTB and establishing cut-off values in a diverse multicentric cohort was developed. CONCLUSIONS: A key outcome was the development of a comprehensive diagnostic tool for diagnosis of dementia and MCI due to varied etiologies, in the diverse socio-demographic setting of India.

Tackling challenges in care of Alzheimer's disease and other dementias amid the COVID-19 pandemic, now and in the future.

We have provided an overview on the profound impact of COVID-19 upon older people with Alzheimer's disease and other dementias and the challenges encountered in our management of dementia in different health-care settings, including hospital, out-patient, care homes, and the community during the COVID-19 pandemic. We have also proposed a conceptual framework and practical suggestions for health-care providers in tackling these challenges, which can also apply to the care of older people in general, with or without other neurological diseases, such as stroke or parkinsonism. We believe this review will provide strategic directions and set standards for health-care leaders in dementia, including governmental bodies around the world in coordinating emergency response plans for protecting and caring for older people with dementia amid the COIVD-19 outbreak, which is likely to continue at varying severity in different regions around the world in the medium term.

Preventing dementia by preventing stroke: The Berlin Manifesto.

The incidence of stroke and dementia are diverging across the world, rising for those in low- and middle-income countries and falling in those in high-income countries. This suggests that whatever factors cause these trends are potentially modifiable. At the population level, neurological disorders as a group account for the largest proportion of disability-adjusted life years globally (10%). Among neurological disorders, stroke (42%) and dementia (10%) dominate. Stroke and dementia confer risks for each other and share some of the same, largely modifiable, risk and protective factors. In principle, 90% of strokes and 35% of dementias have been estimated to be preventable. Because a stroke doubles the chance of developing dementia and stroke is more common than dementia, more than a third of dementias could be prevented by preventing stroke. Developments at the pathological, pathophysiological, and clinical level also point to new directions. Growing understanding of brain pathophysiology has unveiled the reciprocal interaction of cerebrovascular disease and neurodegeneration identifying new therapeutic targets to include protection of the endothelium, the blood-brain barrier, and other components of the neurovascular unit. In addition, targeting amyloid angiopathy aspects of inflammation and genetic manipulation hold new testable promise. In the meantime, accumulating evidence suggests that whole populations experiencing improved education, and lower vascular risk factor profiles (e.g., reduced prevalence of smoking) and vascular disease, including stroke, have better cognitive function and lower dementia rates. At the individual levels, trials have demonstrated that anticoagulation of atrial fibrillation can reduce the risk of dementia by 48% and that systolic blood pressure lower than 140 mmHg may be better for the brain. Based on these considerations, the World Stroke Organization has issued a proclamation, endorsed by all the major international organizations focused on global brain and cardiovascular health, calling for the joint prevention of stroke and dementia. This article summarizes the evidence for translation into action.

Stroke Risk and Vascular Dementia in South Asians.

PURPOSE OF REVIEW: South Asians (SA) are at a higher risk for stroke and vascular dementia due to the disproportionate burden of diabetes, hypertension, and dyslipidemia. This review summarizes the rationale for screening, early detection, and aggressive control of metabolic factors, and critically examines the published literature on primary and secondary stroke prevention. RECENT FINDINGS: South Asians have a higher prevalence of diabetes than non-SA. SA with diabetes are at a higher risk of recurrent ischemic stroke and have a higher incidence of stroke-related dementia compared to non-South Asians. South Asians are one of the fastest-growing ethnic groups worldwide with an unusually increased risk of heart disease and stroke. An accurate assessment of those at risk of stroke and cognitive impairment is urgently needed to plan preventive strategies.

Comparative Effects of Education and Bilingualism on the Onset of Mild Cognitive Impairment.

BACKGROUND: Increasing evidence suggests that life course factors such as education and bilingualism may have a protective role against dementia due to Alzheimer disease. This study aimed to compare the effects of education and bilingualism on the onset of cognitive decline at the stage of mild cognitive impairment (MCI). METHODS: A total of 115 patients with MCI evaluated in a specialty memory clinic in Hyderabad, India, formed the cohort. MCI was diagnosed according to Petersen's criteria following clinical evaluation and brain imaging. Age at onset of MCI was compared between bilinguals and monolinguals, and across subjects with high and low levels of education, adjusting for possible confounding variables. RESULTS: The bilingual MCI patients were found to have a clinical onset of cognitive complaints 7.4 years later than monolinguals (65.2 vs. 58.1 years; p = 0.004), while years of education was not associated with delayed onset (1-10 years of education, 59.1 years; 11-15 years of education, 62.6 years; >15 years of education, 62.2 years; p = 0.426). CONCLUSION: The effect of bilingualism is protective against cognitive decline, and lies along a continuum from normal to pathological states. In comparison, the role of years of education is less robust.

Prevalence and risk factors of asymptomatic carotid artery stenosis in Indian population: An 8-year follow-up study.

BACKGROUND: Asymptomatic carotid artery stenosis (ACAS) is a marker for cerebrovascular disease, coronary atherosclerosis, and death. AIM: To investigate the prevalence of ACAS in the Indian population, and to correlate ACAS with other vascular risk factors. MATERIALS AND METHODS: We prospectively recruited 1500 individuals who were older than 40 years and asymptomatic for cerebrovascular disease between June 2003 and December 2014. Evaluation of vascular risk factors was done for all the participants. Color Doppler of bilateral carotid arteries was performed for all the participants. Carotid stenosis of 1-49% and ≥50% was considered to be mild and significant stenosis, respectively. RESULTS: There were 1016 (67.7%) men, with a mean age of 58.1 ± 10.6 years (age range: 40-98 years). The prevalence of significant carotid stenosis was 5.2%. After adjustment using multiple regression analysis, age >70 years (OR: 2.0; 95% CI: 1.48-2.74), hypertension (OR: 1.8; 95% CI: 1.11-2.96), diabetes (OR: 2.3; 95%CI: 1.45-3.89), smoking (OR: 3.6; 95% CI: 2.18-6.03), dyslipidemia (OR: 4.0; 95% CI: 2.52-6.63), history of migraine (OR: 3.6; 95% CI: 2.54-9.13), history of periodontitis (OR: 3.2; 95% CI: 1.90-5.68), and family history of stroke (OR: 7.1; 95% CI: 4.20-12.2) were significantly associated with >50% stenosis. Duration (>15 years) of hypertension (OR: 2.5; 95% CI: 1.33-6.43), diabetes (OR: 6.2; 95% CI: 3.41-11.3), and smoking (OR: 5.2; 95% CI: 2.20-12.1) markedly worsened the risk. During the 8-year follow up, 14 participants (1.4%) with mild stenosis and 3 participants (4.7%) with significant stenosis developed stroke. CONCLUSIONS: Our study suggests that 5.2% of asymptomatic individuals > 40 years of age harbor significant extracranial carotid artery disease. Presence of multiple vascular risk factors markedly increases the risk of carotid stenosis.