Gerontology Research Programme: Biological, Clinical, Psychosocial and Behavioural Predictors of Health Status in Prospectively Followed-up Cohorts of Elderly Persons

Depressive symptoms and diagnosis (Measuring of Depressive symptoms and assessment of stages of Depression)

时间窗: 20 years - once every 3-4 years

Depressive symptoms are assessed by the 15-item version of the Geriatric Depression Scale (GDS), with a higher score indicating higher depressivity (18). A cut-off score of 5 is used as indicating the presence of depression. Additionally, participants are formally diagnosed by a medically trained research fellow for common mood-related psychiatric conditions using the Structured Clinical Interview for DSM Disorders (SCID) of DSM IV-TR (1), such as Major Depressive Disorder, Minor Depression, Dysthmic Disorder, Mania/Hypomania disorder, Anxiety and panic disorder, Obsessive-compulsive disorder, Post traumatic stress disorder, Psychotic disorder, Mood disorder due to a General Medical Condition and Alcohol abuse disorders, if they screen as positive for depression on the GDS.

Dementia and Mild Cognitive Impairment (MCI) Subtyping (Clinical diagnosis of different stages of Dementia)

时间窗: 20 years - once every 3-4 years

Dementia and MCI is determined by clinical case conference adjudication where geriatric and psychiatric clinicians convene to determine the diagnosis of a case, utilizing the data from (i) Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) (4-5); (ii) Clinical Dementia rating scale: a 5-point scale used to characterize 6 cognitive and functional domain performance: Memory, Orientation, Judgment \& Problem Solving, Community Affairs, Home \& Hobbies, and Personal Care (6). Information to make each rating is obtained through a semi-structured interview of the patient and a reliable informant (e.g. family member). A higher score indicates increased severity of cognitive impairment; (iii) Informant Questionnaire of Cognitive Decline in the Elderly (IQCODE) - reliable informants report on the cognitive state of the participant (7); (iv) a scale on self-reported subjective cognitive difficulties; and (v) a neuropsychological assessment battery (described below).

Frailty (Measuring the physical and Cognitive Frailty)

时间窗: 20 years - once every 3-4 years

Physical frailty was assessed by scores (1 = present, 0 = absent) for five components (shrinking, weakness, slowness, exhaustion, and low Physical Activity (PA)) proposed by Fried et al (3), with the following operational modifications: (i) Shrinking was defined by unintentional weight loss of 4 kg or more in the past 6 months, or BMI less than 18.5 kg/m2, or calf circumference of 31 cm or less. (ii) Weakness was assessed by knee extension strength task in kilogram. (iii) Slowness was assessed by a gait speed test (15). (iv) Exhaustion was measured as a summed score of 3 questions (1-5), "Did you have lots of energy/feel tired (reverse-scored, rs)/worn out (rs)?" (16). A score of \<10 was used to denote exhaustion. (v) Low PA was measured by the LASA PA scale, with those falling below the local gender-specific lowest quintile deemed as low PA (17). Participants are categorised by their total scores as robust (score = 0), pre-frail (score = 1-2), and frail (score = 3-5).

Successful ageing (Measuring the biological, psycho-social and lifestyle factors associated with Successful Ageing)

时间窗: 20 years - once every 3-4 years

Successful aging is previously defined (25). Briefly, a score of successful ageing reflects the overall and physical health, cognitive, emotional, social well-functioning, including life engagement \& satisfaction. Physical health and functional well-being was defined as a "good/excellent" self-reported health and IADL independence (20). Cognitive well-functioning and emotional wellbeing was denoted by a minimum MMSE score of 26 (4), and a score below 5 on the GDS (≤5) (18). Social functioning and active engagement in life activities was assessed using a validated questionnaire (26) on participation levels in social, recreational, civic activities, voluntary work, employment/business, and domestic activities. Overall positive life satisfaction was determined using the Life Satisfaction Scale that assessed interest in life, happiness, loneliness, and general ease of living (27). Total summed score ranges from 4 to 18, with the lowest decile indicating a positive life satisfaction.

Global and specific domain cognitive functioning ability (Measuring of Global and Specific domain of Cognitive functions)

时间窗: 20 years - once every 3-4 years

MMSE (4) and MoCA (5) - 30 items, total scores range from 0-30, higher scores indicate better cognitive functioning. A cut-off of a score of =\<25 is determined as screening positive for cognitive impairment. Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) (8) - measures immediate memory, visuospatial ability, language, attention, delayed memory, and a global cognitive functioning score (a summation of domain scores). A neurocognitive battery measures immediate and delayed memory/learning, visuospatial ability, language, attention, and executive functioning. All domains are calculated by weighted averages of age and education adjusted scores. Tests: (i) Digit Span forward and backwards tasks (9); (ii) Rey's Auditory Verbal Learning Test (10); (iii) Story Memory Test (11); (iv) Brief Visuospatial Memory Test - Revised (12); (v) Boston Naming Test (13); (vi) Clock Reading Test; (viii) Colour Trials 1 and 2 (14); (ix) Block Design task (9).