The Dementia and Disability Project in Thai Elderly: rational, design, methodology and early results.

BACKGROUND: A strong inverse relationship of functional limitation and socioeconomic status has been established in western ageing society. Functional limitation can be related to chronic diseases, disuse, cognitive decline, and ageing. Among chronic diseases in the Thai population, cerebrovascular diseases, diabetes, and arthritis are common. These factors are known to contribute to disability and poor quality of life in the elder population. Neuropsychiatric problems, cognitive decline, dementia, and cultural issues in elderly people also can alter the quality of life of the elderly. METHODS: The Dementia and Disability Project in Thai Elderly (DDP) aims at comprehensively assessing community dwelling Thai elderly to understand the relationship between disability and motor function, neuropsychiatric symptoms, cognitive function, and chronic diseases. The DDP is the first study to look at the prevalence and etiology of dementia and of mild cognitive impairment (MCI) in Thai elders and to explore the relationship of cognition, disability, small vessel diseases and cortical degeneration with neuroimaging in Thai elderly people. 1998 Thai elders were screened in 2004-2006 and diagnosed as having MCI or dementia. 223 elders with MCI or dementia and cognitively normal elderly had brain magnetic resonance imaging (MRI) or at baseline. 319 elders from the 3 groups had blood tests to investigate the risks and possible etiologies of dementia including genotyping at baseline. RESULTS: The mean age of elders in this study is 69.51(SD=6.71, min=60, max=95) years. 689(34.9%) are men and 1284(65.1%) are women. Mean body weight was 58.36(SD=11.20) kgs. The regression model reveals that performance on gait and balance and serum triglyceride predicts activity of daily living performance (adjusted r2 = 0.280, f=2.644, p=0.003). The majority of abnormal gait in Thai elders was lower level gait disturbance. Only 1.5% (29/1952) had highest level gait disorders. 39.5% of 1964 subjects were free of chronic diseases. Treatment gap (indicating those who have untreated or inadequate treatment) of diabetes mellitus and hypertension in Thai elders in this study was 37% and 55.5% respectively. 62.6% of Thai elders have ApoE3E3 allele. Prevalence of positive ApoE4 gene in this study is 22.85%. 38.6% of Thai elders who had MRI brain study have moderate to severe white matter lesions. CONCLUSION: The large and comprehensive set of measurements in DDP allows a wide-ranging explanation of the functional and clinical features to be investigated in relation to white matter lesions or cortical atrophy of the brain in Thai elderly population. An almost 2 year follow up was made available to those with MCI and dementia and some of the cognitively normal elderly. The longitudinal design will provide great understanding of the possible contributors to disability in the elderly and to the progression of cognitive decline in Thai elders.

A new measurement of activities of daily living for Thai elderly with dementia.

BACKGROUND: Activities of daily living (ADL) vary across cultures, and measure of ADL needs to be specific to the population under study. We developed an ADL measure for Thai elderly with dementia and investigated the reliability and validity of this instrument. MATERIALS AND METHODS: Item construction was accomplished with a panel of neurologists and a rehabilitation medicine physician. One hundred eighty-one subjects were interviewed using the Thai ADL measure. Of this sample, one hundred fifty-nine had dementia according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition criteria. These data were analyzed for internal consistency; concurrent validity was determined by comparison with the Barthel Index, Functional Assessment Questionnaire (FAQ), Thai Mental State Exam (TMSE), and Clinical Dementia Rating (CDR) scale; and discriminant validity was determined by comparison with the Neuropsychiatric Inventory (NPI). Thirty subjects were tested to determine interrater and test-retest reliability. RESULTS: Thai ADL measure was composed of six basic ADL and seven instrumental ADL. It had high correlation with TMSE scores (r = -.69), CDR scores (r = .81), Barthel Index scores (r = -.80), and FAQ scores (r = .88), and moderate correlation with NPI scores (r = .46). The instrument had high test-retest reliability (intraclass correlation coefficient [ICC] = .92, .89) and high interrater reliability (ICC = .96, .93). CONCLUSION: The Thai ADL scale is easy to use and it has high reliability. It had high concurrent validity with previously published ADL scales. The methodology used to develop the Thai ADL scale can provide a model for creating culturally competent ADL scales.