Sains Malaysiana 45(9)(2016): 1351–1355

Cognitive Health of Older Persons in Longitudinal Ageing Cohort Studies

(Kajian Kohort Penuaan Longitud Kesihatan Kognitif dalam Kalangan Warga Emas)

NG TZE PIN*

Department of Psychological Medicine and Gerontology Research Programme, Yong Yoo Lin School of Medicine, National University of Singapore, 21 Lower Kent Ridge Road, 119077 Singapore

Received: 21 December 2015/Accepted: 13 May 2016

ABSTRACT

Dementia poses a major global burden of care to society and health systems in ageing populations. The majority (over 60%) of persons with dementia in the world are found in Asia and developing countries with rapid rates of population ageing. Improving and maintaining the cognitive health of older persons is vital to national strategies for dementia prevention. Increasing numbers of population-based ageing cohort studies in the past decade have provided a better understanding of the factors that contribute to cognitive function and decline in old age. The roles of major demographic, psychosocial, lifestyle, behavioral and cardiovascular risk factors contributing to cognitive health were discussed using examples from the Singapore Longitudinal Ageing Studies. They include socio-demographic factors, particularly education and marital status, leisure time activity such as physical activity, social engagement and mental activities, psychological factors such as depression, cardiovascular and metabolic risk factors: obesity, diabetes, hypertension and dyslipidemia, and the metabolic syndrome, under-nutrition, low albumin, low hemoglobin, nutritional factors such as blood folate, B12 and homocysteine, omega-3 poly-unsaturated fatty acids, tea drinking and curcumin-rich turmeric in curry meals. These factors are found to be associated variously with cognitive functions (memory and learning, language, visuospatial, attention and information processing speed), rates of cognitive impairment and cognitive decline, or increased risk of developing MCI and progression to dementia.

Keywords: Aging; cognitive function; dementia; older adult; risk factor

ABSTRAK

Secara global, demensia menjadi beban jagaan utama terhadap masyarakat dan sistem kesihatan dalam kalangan populasi tua. Lebih daripada 60% individu yang mempunyai masalah demensia terdiri daripada masyarakat negara Asia serta negara-negara membangun yang mempunyai kadar kenaikan populasi tua yang mendadak. Langkah meningkatkan dan mengekalkan kesihatan mental bagi warga emas merupakan strategi yang amat penting sebagai pencegahan masalah demensia. Peningkatan jumlah kajian kohot berkenaan populasi ini telah meningkatkan pemahaman terhadap faktor yang boleh mempengaruhi fungsi kognitif dan penurunan fungsi kognitif di usia tua. Faktor yang mempengaruhi kesihatan kognitif yang dibincangkan adalah berdasarkan Kajian Penuaan Longitud Singapura iaitu faktor demografi, psikososial, gaya hidup, tingkah laku dan risiko kardiovaskular. Faktor sosiodemografi termasuklah pendidikan dan status perkahwinan manakala aktiviti masa lapang melibatkan aktiviti fizikal, penglibatan sosial dan aktiviti yang menggunakan daya mental. Faktor signifikan melibatkan psikososial seperti kemurungan bersama faktor risiko kardiovaskular dan metabolik termasuklah obesiti, diabetes, hipertensi dan dislipidemia dan sindrom metabolik, kekurangan nutrisi, paras albumin serta hemoglobin yang rendah. Selain itu, faktor pemakanan seperti paras folat dalam darah, B12 dan homosisteina, omega-3 asid lemak poli tak tepu, pengambilan minuman teh dan kunyit yang tinggi kandungan kurkumin dalam masakan berasaskan kari didapati penting. Faktor ini berkait dengan pelbagai fungsi kognitif (memori dan pembelajaran, bahasa, visuoreruang, perhatian dan kelajuan pemprosesan maklumat), kadar gangguan dan penurunan fungsi kognitif atau peningkatan risiko kemerosotan kognitif ringan dan progresi kepada masalah demensia.

Kata kunci: Demensia; faktor risiko; fungsi kognitif; penuaan; warga emas

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*Corresponding author; email: pcmngtp@nus.edu.sg