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Objectives: Mild cognitive impairment (MCI) refers to an early but abnormal state of cognitive impairment with minimal functional impairment. The present study aimed to evaluate the validity of Fuld Object Memory Evaluation (FOME) as a measure of episodic memory function., Method: The study sample included 204 Chinese older adults with cognitive impairments. The participants completed five recall trials and a delayed trial in FOME, neurocognitive measures on digit spans and trail making, and daily functioning. Discriminative power of FOME to differentiate between MCI and dementia was inspected via receiver operating characteristic curve analysis., Results: FOME showed good test-retest reliability and convergent validity with digit spans and trail making. Controlling for gender, age, and education, lower levels of FOME total retrieval, verbal fluency, and daily functioning significantly predicted a higher likelihood of dementia compared to MCI. The optimal cut-off scores for total retrieval, verbal fluency, and daily functioning to differentiate dementia were 37/38 (77% sensitivity and 83% specificity), 28/29 (85% sensitivity and 72% specificity), and 14/15 (92% sensitivity and 78% specificity), respectively, in the younger subgroup. The corresponding figures were 34/35 (69% sensitivity and 76% specificity) and 27/28 (92% sensitivity and 62% specificity), and 11/12 (74% sensitivity and 80% specificity), respectively, in the older subgroup., Conclusion: The findings support the FOME as a valid assessment tool of episodic memory function in older Chinese adults. The combined use of FOME and daily functioning is recommended to distinguish persons with dementia from MCI.

ABSTRACTObjectives:Loneliness and social networks have been extensively studied in relation to cognitive impairments, but how they interact with each other in relation to cognition is still unclear. This study aimed at exploring the interaction of loneliness and various types of social networks in relation to cognition in older adults., Design: a cross-sectional study., Setting: face-to-face interview., Participants: 497 older adults with normal global cognition were interviewed., Measurements: Loneliness was assessed with Chinese 6-item De Jong Gierverg's Loneliness Scale. Confiding network was defined as people who could share inner feelings with, whereas non-confiding network was computed by subtracting the confiding network from the total network size. Cognitive performance was expressed as a global composite z-score of Cantonese version of mini mental state examination (CMMSE), Categorical verbal fluency test (CVFT) and delayed recall. Linear regression was used to test the main effects of loneliness and the size of various networks, and their interaction on cognitive performance with the adjustment of sociodemographic, physical and psychological confounders., Results: Significant interaction was found between loneliness and non-confiding network on cognitive performance (B = .002, β = .092, t = 2.099, p = .036). Further analysis showed a significant interaction between loneliness and the number of family members in non-confiding network on cognition (B = .021, β = .119, t = 2.775, p = .006)., Conclusions: Results suggested that a non-confiding relationship with family members might put lonely older adults at risk of cognitive impairment. Our study might have implications on designing psychosocial intervention for those who are vulnerable to loneliness as an early prevention of neurocognitive impairments.

Background: Scalp to cortex distance (SCD), as a key technological parameter, has been highlighted in the guidelines of non-invasive brain stimulation. However, in the context of age-related brain changes, the region-specific SCD and its impact on stimulation-induced electric field remain unclear., Objective: This study aimed to investigate the region-specific SCD and its relationship with morphometric features and cognitive function in age- and disease-specific populations., Methods: We analyzed the SCD and cortical thickness (CT) of left primary motor cortex (M1) and dorsolateral prefrontal cortex (DLPFC) in 214 cognitively normal adults and 43 dementia patients. CT-adjusted SCD was used to control the influence of CT on SCD. Head model was developed to simulate the impact of SCD on the electric field induced by transcranial electrical stimulation., Results: We found age-related increased SCD in the left DLPFC (p < 0.001), but not M1 (p = 0.134), and dementia-related increased SCD in both left DLPFC (p < 0.001) and M1 (p < 0.001). CT-adjusted SCD showed greater region-specific impact on left DLPFC rather than M1. The electric field induced by stimulation was consequently decreased with the increased SCD across normal aging and dementia groups., Conclusions: Age and dementia have differential impacts on the SCDs of left DLPFC and M1. The findings suggest that it is important to be aware of region-specific distance measures when conducting neuromodulation in individuals with old age and dementia.

Importance: Associations between late-life participation in intellectual activities and decreased odds of developing dementia have been reported. However, reverse causality and confounding effects due to other health behaviors or problems have not been adequately addressed., Objective: To examine whether late-life participation in intellectual activities is associated with a lower risk of incident dementia years later, independent of other lifestyle and health-related factors., Design, Setting, and Participants: A longitudinal observational study was conducted at all Elderly Health Centres of the Department of Health of the Government of Hong Kong among 15 582 community-living Chinese individuals age 65 years or older at baseline who were free of dementia, with baseline evaluations performed January 1 to June 30, 2005, and follow-up assessments performed from January 1, 2006, to December 31, 2012. Statistical analysis was performed from January 1, 2015, to December 31, 2016., Main Outcomes and Measures: The main outcome was incident dementia as diagnosed by geriatric psychiatrists in accordance with the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, or a Clinical Dementia Rating of 1 to 3. At baseline and follow-up interviews, self-reported information on participation in intellectual activities within 1 month before assessment was collected. Examples of intellectual activities, which were described by a local validated classification system, were reading books, newspapers, or magazines; playing board games, Mahjong, or card games; and betting on horse racing. Other important variables including demographics (age, sex, and educational level), physical and psychiatric comorbidities (cardiovascular risks, depression, visual and hearing impairments, and poor mobility), and lifestyle factors (physical exercise, adequate fruit and vegetable intake, smoking, and recreational and social activities) were also assessed., Results: Of the 15 582 individuals in the study, 9950 (63.9%) were women, and the median age at baseline was 74 years (interquartile range, 71-77 years). A total of 1349 individuals (8.7%) developed dementia during a median follow-up period of 5.0 years. Multivariable logistic regression analysis showed that the estimated odds ratio for incident dementia was 0.71 (95% CI, 0.60-0.84; P < .001) for those with intellectual activities at baseline, after excluding those who developed dementia within 3 years after baseline and adjusting for health behaviors, physical and psychiatric comorbidities, and sociodemographic factors., Conclusions and Relevance: Active participation in intellectual activities, even in late life, might help delay or prevent dementia in older adults.

Objective: Prospective studies on late-life anxiety disorders suggested that history of anxiety symptoms may be predictive of cognitive decline in old age. However, the relationship between anxiety and cognitive decline is still inconclusive due to heterogeneity in sample and methodology. This study was to explore how baseline anxiety symptoms associated with the change of memory in older people without cognitive impairment over a 3-year period., Methods: This was a 3-year prospective study on 91 cognitively normal older adults with anxiety symptoms. They were matched with 91 controls based on age, gender, and education. Anxiety symptoms were assessed with Revised Clinical Interview Schedule (CIS-R). Physical health was assessed with Chronic Illness Rating Scale (CIRS). Cognitive performance was measured using Cantonese version of the mini-mental state examination (CMMSE); 10-minute delay recall; Category verbal fluency test (CVFT); Trail making tests (TMT); and digit and visual span tests. Outcomes were determined as the change of cognitive performance over a 3-year period., Results: As expected, anxiety group had higher score in CIRS score (t = 4.45, P < .001) and CIS-R score (t = 9.24, P < .001) than control group. Linear regression showed that baseline anxiety symptoms were associated with change in delayed recall (B = 0.77, P = 0.027, 95% CI = 0.09-1.46), after adjusting for cognitive performance, physical, and mental health statuses., Conclusions: Anxious healthy older adults showed specific decline in episodic memory over a 3-year interval. Our result suggested that anxiety symptoms are predictive of episodic memory decline in cognitively healthy older adults and may be an early sign of neurodegenerative disorders., (Copyright © 2018 John Wiley & Sons, Ltd.)

Background: Memory and learning, as the core brain function, shows controversial results across studies focusing on aging and dementia. One of the reasons is because of the multi-faceted nature of memory and learning. However, there is still a dearth of comparable proxies with psychometric and morphometric portrait in clinical and non-clinical populations., Objective: We aim to investigate the proxies of memory and learning function with direct and derived measures and examine their associations with morphometric features in senior adults with different cognitive status., Methods: Based on two modality-driven tests, we assessed the component-specific memory and learning in the individuals with high performing (HP), normal aging, and neurocognitive disorders (NCD) (n = 488). Structural magnetic resonance imaging was used to measure the regional cortical thickness with surface-based morphometry analysis in a subsample (n = 52)., Methods: Compared with HP elderly, the ones with normal aging and minor NCD showed declined recognition memory and working memory, whereas had better learning performance (derived scores). Meanwhile, major NCD patients showed more breakdowns of memory and learning function. The correlation between proxies of memory and learning and cortical thickness exhibited the overlapped and unique neural underpinnings., Conclusions: The proxies of memory and learning could be characterized by component-specific constructs with psychometric and morphometric bases. Overall, the constructs of memory are more likely related to the pathological changes, and the constructs of learning tend to reflect the cognitive abilities of compensation.

Lifetime prevalence of psychotic disorders varies widely across studies. Epidemiological surveys have rarely examined prevalences of specific psychotic disorders other than schizophrenia, and the majority used a single-phase design without employing clinical reappraisal interview for diagnostic verification. The current study investigated lifetime prevalence, correlates and service utilization of schizophrenia-spectrum, affective, and other non-affective psychotic disorders in a representative sample of community-dwelling Chinese adult population aged 16-75 years (N = 5719) based on a territory-wide, population-based household survey for mental disorders in Hong Kong. The survey adopted a 2-phase design comprising first-phase psychosis screening and second-phase diagnostic verification incorporating clinical information from psychiatrist-administered semi-structured interview and medical record review to ascertain DSM-IV lifetime diagnosis for psychotic disorders. Data on sociodemographics, psychosocial characteristics and service utilization were collected. Our results showed that lifetime prevalence was 2.47% for psychotic disorder overall, 1.25% for schizophrenia, 0.15% for delusional disorder, 0.38% for psychotic disorder not otherwise specified, 0.31% for bipolar disorder with psychosis, and 0.33% for depressive disorder with psychosis. Schizophrenia-spectrum disorder was associated with family history of psychosis, cigarette smoking and variables indicating socioeconomic disadvantage. Victimization experiences were significantly related to affective psychoses and other non-affective psychoses. Around 80% of participants with any psychotic disorder sought some kind of professional help for mental health problems in the past year. Using comprehensive diagnostic assessment involving interview and record data, our results indicate that approximately 2.5% of Chinese adult population had lifetime psychotic disorder which represents a major public health concern., (© The Author 2017. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: dietary modification can potentially reduce dementia risk, but the importance of fruits and the amount of vegetables and fruits required for cognitive maintenance are uncertain. We examined whether the minimal daily requirement of vegetables and fruits recommended by the World Health Organization (WHO) would independently lower dementia risk., Methods: in this population-based observational study, we examined the diet of 17,700 community-living dementia-free Chinese older adults who attended the Elderly Health Centres in Hong Kong at baseline and followed their cognitive status for 6 years. In line with the WHO recommendation, we defined the cutoff for minimal intake of vegetables and fruits as at least three and two servings per day, respectively. The study outcome was incident dementia in 6 years. Dementia was defined by presence of clinical dementia in accordance with the 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) or Clinical Dementia Rating of 1-3., Results: multivariable logistic regression analysis showed that the estimated odds ratios for incident dementia were 0.88 (95% confidence interval 0.73-1.06; P = 0.17) for those consuming at least three servings of vegetables per day, 0.86 (0.74-0.99; P < 0.05) for those consuming at least two servings of fruits per day and 0.75 (0.60-0.95; P = 0.02) for those consuming at least these amounts of both at baseline, after adjusting for age, gender, education, major chronic diseases, physical exercise and smoking., Conclusion: having at least three servings of vegetables and two servings of fruits daily might help prevent dementia in older adults., (© The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.All rights reserved. For permissions, please email: journals.permissions@oup.com)

Background: Mild cognitive impairment (MCI) is a prevalent symptom associated with the increased risk of dementia. There are many cognitive tests available for detection of MCI, and investigation of the diagnostic performance of the tests is deemed necessary., Objective: This study aims to evaluate the diagnostic performance of different cognitive tests used for MCI detection., Data Sources: A list of cognitive tests was identified in previous reviews and from online search engines. Literature searches were performed on each of the cognitive tests in MEDLINE, Embase, and PsycINFO from the earliest available dates of individual databases to December 31, 2016. Google Scholar was used as a supplementary search tool., Study Selection: Studies that were used to assess the diagnostic performance of the cognitive tests were extracted with inclusion and exclusion criteria. Each test's performance was compared with the standard diagnostic criteria. Bivariate random effects models were used to summarize the test performance as a point estimate for sensitivity and specificity, and presented in a summary receiver operating characteristic curve. Reporting quality and risk of bias were evaluated., Results: A total of 108 studies with 23,546 participants were selected to evaluate 9 cognitive tests for MCI detection. Most of the studies used the Mini-Mental State Examination (MMSE) (n = 58) and the Montreal Cognitive Assessment (MoCA) (n = 35). The combined diagnostic performance of the MMSE in MCI detection was 0.71 sensitivity [95% confidence interval (CI): 0.66-0.75] and 0.74 specificity (95% CI: 0.70-0.78), and of the MoCA in MCI detection was 0.83 sensitivity (95% CI: 0.80-0.86) and 0.75 specificity (95% CI: 0.69-0.80). Among the 9 cognitive tests, recall tests showed the best diagnostic performance with 0.89 sensitivity (95% CI: 0.86-0.92) and 0.84 specificity (95% CI, 0.79-0.89). In subgroup analyses, long- or short-delay recall tests have shown better performance than immediate recall tests., Conclusions: Recall tests were shown to be the most effective test in MCI detection, especially for the population with symptoms of memory deterioration. They can be potentially used as the triage screening test for MCI in primary care setting. But when a patient shows cognitive impairments beyond memory deterioration, a more comprehensive test such as the MoCA should be used., (Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.)

Objectives: Previous studies have reported that the prevalence of late life anxiety disorders varies between 3.2% and 15.3%. Despite its high prevalence, anxiety disorders are still under-recognized in old age. This study evaluated the association among health, psychosocial factors, lifestyle choices, cognitive function and anxiety disorders in the older population in Hong Kong., Methods: Six hundred and thirteen volunteer participants aged 60 years or above were interviewed for their socio-demographic background, physical and mental health statuses, social network, cognitive function and their activity engagement style. Ascertainment of diagnosis of anxiety disorders was based on the use of ICD-10 diagnostic criteria generated by the Revised Clinical Interview Schedule (CIS-R) algorithms., Results: According to the ICD-10 diagnostic criteria generated by the CIS-R algorithms, 4.4% (N = 27) had mixed anxiety and depressive disorder, 2.5% (N = 15) had generalized anxiety disorders and 0.2% (N = 1) had other anxiety disorders (Phobia). Individuals with anxiety disorders had more gastrointestinal conditions (OR = 2.66, 95% CI 1.48-4.76) and genitourinary problems (OR = 1.96, 95% CI 1.05-3.65), poor 10-min delayed recall (OR = 0.68, 95% CI 0.56-0.83), worse abstract thinking (OR = 0.65, 95% CI 0.49-0.85) and poor social networking in confidante relationship (OR = 0.88, 95% CI 0.79-0.98). Lifestyle activity engagement was not associated with the presence of anxiety disorders., Conclusions: Older adults with anxiety disorders appeared to have greater medical comorbidity and lower cognitive function. While anxiety may affect memory performance, future studies are needed to explore if anxiety symptom may reflect early neurodegeneration that easily escapes clinical attention. Copyright © 2016 John Wiley & Sons, Ltd., (Copyright © 2016 John Wiley & Sons, Ltd.)

Objective: To examine the effects of using cognitive reappraisal to find positive gains on caregivers' depressive symptoms, burden, and psychological well-being., Method: Ninety-six caregivers of persons with Alzheimer's disease were randomly assigned to receive a benefit-finding intervention or 1 of 2 treatment-as-usual conditions, namely, simplified psychoeducation (lectures only; SIM-PE) or standard psychoeducation (STD-PE). Each participant received 4 biweekly interventions of 3 hr each, over a 2-month period, at home., Results: Results showed that benefit-finding participants reported lower depressive symptoms after treatment, when compared with either SIM-PE (d = -0.46) or STD-PE (d = -0.50) participants. They also reported less role overload when compared with STD-PE participants (d = -0.46). Self-efficacy in controlling upsetting thoughts was a mediator for some of the treatment effects., Conclusion: Finding positive gains is an effective intervention to reduce depressive symptoms among Alzheimer caregivers. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)

Objective: This study investigated the potential of physical exercise habit as a lifestyle modification against cognitive and functional decline at the community level., Methods: A total of 454 community-dwelling Chinese older adults without dementia participated in the Hong Kong Memory and Ageing Prospective Study at baseline and follow-up at 5 years. Their cognitive and functional performances were assessed by the Cantonese version of the Mini-Mental State Examination (CMMSE) and the Chinese version of Disability Assessment in Dementia (DAD). Hierarchical multiple regression analyses were performed to examine whether physical exercise was a significant predictor of the follow-up CMMSE and DAD scores after controlling for the covariates. Subgroup analyses were performed with a group of 127 participants with mild cognitive impairment at baseline., Results: Physical exercise habit was a significant predictor for both the follow-up CMMSE scores and DAD scores. Participants with exercise habits of 5 years or more showed better cognitive and functional performances at follow-up. Participants who picked up exercise habits only after the baseline assessment also demonstrated better functioning at follow-up. The same patterns were observed in the subgroup analyses with the mild cognitive impairment group., Conclusion: Results suggested that prolonged exercise habit is required for positive effects on cognition to emerge, but benefits on functioning can be observed when individuals take up an exercise habit later in life or even after the beginning of cognitive decline. These findings are encouraging in promoting an exercise habit among older adults living in the community., (Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.)

Processing speed is an updated diagnostic factor for neurocognitive disorders (NCD) in DSM-5. This study investigated the characteristics of processing speed and their diagnostic values in NCD patients. A flanker test was conducted in 31 adults with NCD due to vascular disease (NCD-vascular), 36 patients with NCD due to Alzheimer's disease (NCD-AD), and 137 healthy controls. The processing speed was evaluated using two measurements: mean reaction time (RT) and intra-individual variability of RT. Mean RT represents the global processing speed. Intra-individual variability of RT is the short-term fluctuation of RT and consists of two indices, which are intra-individual coefficient of variation of reaction time (ICV-RT) and intra-individual standard deviations (iSD). We observed elevated ICV-RT and iSD in NCD-AD and NCD-vascular patients. Additionally, there was a slowed RT in NCD-AD patients. The intra-individual variability of RT had a moderate power to differentiate NCD subgroups. The mean RT was able to discriminate the NCD-AD from NCD-vascular patients. Our findings highlight the clinical utility of the combined 'two-level' measurements of processing speed to distinguish between individuals with different cognitive status. Furthermore, the 'two-level' features of processing speed embedded in the psychometric property may also reflect the diverse aetiology underlying certain 'disease-specific' neurocognitive disorders.

Background: Processing speed has been highlighted as a diagnostic item for neurocognitive disorders (NCD) in DSM-5. The utility of information processing speed (IPS) enclosed with multiscale constructs in the diagnosis of NCD warrants exploration., Objective: We aimed to investigate the IPS with two types of measurements in the patients with NCD due to vascular disease (NCD-vascular) and NCD due to Alzheimer's disease (NCD-AD), and examine the associations between IPS measures and morphometric features., Methods: The IPS was evaluated using trail making test (TMT) and flanker test (n = 204). Direct scores, derived scores, and reaction time (RT) were used as IPS measures. Further, surface-based morphometry cortical volume was calculated in a subsample (n = 44) with structural MRI data., Results: All IPS measures showed a significant value to differentiate NCD patients from healthy subjects. Only mean RT could distinguish NCD-AD from NCD-vascular groups. TMT-B score and difference score were correlated with gray matter volume (GMV) of inferior frontal gyrus, precuneus and superior temporal cortex. Mean RT was associated with the GMV of post-central gyrus (r = -0.327, p = 0.035), and executive speed was associated with inferior frontal cortex (r = -0.475, p = 0.001), cingulate gyrus (r = -0.497, p = 0.001), and superior temporal gyrus (r = -0.36, p = 0.019)., Conclusion: The cognitive and morphometric correlates of IPS measures indicate that complex IPS might be decomposed into the domain-specific components with corresponding neural underpinnings. Our findings may also provide essential insights into the diagnostic item of NCD.

Background: Intra-individual (IIV) of reaction time (RT), as the short-term fluctuations of RT-based performance, has been reported to be susceptible to cognitive ageing. The current study aimed to examine IIV of RT and its relationships with cognitive performance in cognitively normal senior adults. Methods: We evaluated 137 community-dwelling elderly (mean age: 72.41 ± 3.99) with a comprehensive neuropsychological battery and a RT-based test. Intraindividual coefficient of variation of reaction time (ICV-RT) was used to evaluate the IIV. Pearson's correlation and hierarchical multiple regression analyses were employed to assess the relationships between IIV and the scores of cognitive function. Results: Advancing age was accompanied with declined cognitive function and increased IIV. ICV-RT was negatively correlated with the score of Montreal Cognitive Assessment Hong Kong version (HK MoCA) across three types of flanker. Hierarchical multiple regression showed that ICV-RT was a significant predictor of HK MoCA (β = -0.294, p = 0.001). Conclusion: Increased IIV is consistently associated with and contributed to the age-related decline of cognitive performance in senior adults. The utility of IIV in predicting further deterioration should be carefully postulated with prospective studies.

Background: With the proportion of older adults in Hong Kong projected to double in size in the next 30 years, it is important to develop measures for detecting individuals in the earliest stage of Alzheimer's disease (AD, 0.5 in Clinical Dementia Rating, CDR). We tested the utility of a non-verbal prospective memory task (PM, ability to remember what one has to do when a specific event occurs in the future) as an early marker for AD in Hong Kong Chinese., Methods: A large community dwelling sample of older adults who are healthy controls (CDR 0, N = 125), in the earliest stage of AD (CDR 0.5, N = 125), or with mild AD (CDR 1, N = 30) participated in this study. Their reaction time/accuracy data were analyzed by mixed-factor analyses of variance to compare the performance of the three CDR groups. Logistic regression analyses were performed to test the discriminative power of these measures for CDR 0 versus 0.5 participants., Results: Prospective memory performance declined as a function of AD severity: CDR 0 > CDR 0.5 > CDR 1, suggesting the effects of early-stage AD and AD progression on PM. After partialling out the variance explained by psychometric measures (e.g., ADAS-Cog), reaction time/accuracy measures that reflected the PM still significantly discriminated between CDR 0 versus 0.5 participants in most of the cases., Conclusion: The effectiveness of PM measures in discriminating individuals in the earliest stage of AD from healthy older adults suggests that these measures should be further developed as tools for early-stage AD discrimination.

Background: To investigate dimensions of caregiver burden through factor analysis of the Zarit Burden Interview (ZBI), and to examine predictors of different dimensions of burden., Methods: Confirmatory factor analyses were performed on 395 Hong Kong Chinese Alzheimer caregivers to examine whether several proposed factor structures fit the data well. Subsequently, participants were split into two roughly equal subsamples, for the purpose of identifying the most optimal factor structure through exploratory factor analysis in Sample A ( n = 183) and an independent verification through confirmatory factor analysis in Sample B ( n = 212). ZBI subscales representing the established factors were correlated with caregiver and care-recipient variables known to be associated with burden., Results: Confirmatory factor analyses showed that factor models reported elsewhere did not fit the data well. Subsequently, exploratory factor analysis in Sample A suggested a 4-factor structure. After dropping three items due to poor factor loadings, the 4-factor structure was found to fit the data moderately well in Sample B. The four factors tapped personal strain, captivity, self-criticism, and loss of control. However, self-criticism was basically unrelated to the other three factors and showed a rather different pattern of correlations with caregiver and care-recipient variables. Self-criticism was more common among child caregivers and those who did not live with the care-recipient and was less involved in day-to-day care, yet feeling obligated and close to the care-recipient., Conclusions: The dimensions of caregiver burden may be culturally specific. More research is needed to examine cultural considerations in measuring caregiver burden.

Hong Kong was a UK colony before 1997 but has since been a Special Administrative Region of the People's Republic of China. It is located in southern China and has an area of 1104 km 2 . Approximately 95% of Hong Kong's population is ethnic Chinese. Hong Kong is a developed capitalist economy, with a gross domestic product of US$301.6 billion (2009 estimate), of which about 5.5% is spent on healthcare and about 0.24% on mental health (World Health Organization, 2005). Despite the relatively low level of spending on healthcare, Hong Kong nevertheless has one of the longest life expectancies in the world (79.2 years for men; 84.8 years for women) and a very low infant mortality rate (2.93 per 1000 live births) (Central Intelligence Agency, 2010).