Sung Man Chang

A nationwide survey on the prevalence of dementia and mild cognitive impairment in South Korea.

We investigated the prevalence of dementia and mild cognitive impairment (MCI) and the factors associate with risk of dementia from a representative nationwide sample of Korean elders. 8,199 randomly-sampled Koreans aged 65 years or older were invited to participate in the Phase I screening assessment using Mini-Mental State Examination by door-to-door home visit, and 6,141 subjects (response rate = 74.9%) responded. Among them, 2,336 subjects were invited to participate in the Phase II diagnostic assessment for dementia and MCI, and 1,673 subjects responded (response rate = 71.6%). Diagnostic assessments were administered using the Korean version of the Consortium to Establish a Registry for Alzheimers Disease Assessment Packet (CERAD-K) Clinical Assessment Battery. The CERAD-K Neuropsychological Assessment Battery was used for diagnosing MCI. Age-, gender-, education-, and urbanicity-standardized prevalence of dementia was estimated to be 8.1% (95% CI = 6.9-9.2) for overall dementia and 24.1% (95% CI = 21.0-27.2) for MCI. Alzheimers disease (AD) was the most prevalent type (5.7%) followed by vascular dementia (2.0%). Amnestic subtype (20.1%) was much more prevalent than nonamnestic subtype in MCI (4.0%). Older age, being male, lower education level, illiteracy, smoking, and histories of head trauma or depression were associated with increased dementia risk, and alcohol use and moderately intense exercise were associated with decreased dementia risk. We expect numbers of dementia patients to double every 20 years until 2050 in Korea and expect AD to account for progressively more dementia cases in the future.

Lifetime Prevalence and Correlates of Suicidal Ideation, Plan, and Single and Multiple Attempts in a Korean Nationwide Study

This was the first Korean national study to evaluate prevalence and correlates of suicidal behavior, and to compare multiple and single attempts. A total of 6510 adults completed face-to-face interviews (response rate, 81.7%) through randomly chosen one-person-per-households. Lifetime prevalence and correlates were evaluated with the Korean version of Composite International Diagnostic Interview (K-CIDI), and a questionnaire to inquire about suicidal behaviors. The lifetime prevalence of suicidal ideation, plan, and attempt in South Korea was 15.2%, 3.3%, and 3.2% (single 2.1% and multiple 1.1%), respectively. Younger age was associated with attempts and more strongly associated with multiple attempts. Attempts were the most strongly associated with mood disorders, especially bipolar disorder, which was more strongly associated with multiple attempts. In conclusion, suicidal behaviors are highly prevalent in Korea, especially in young adults. Bipolar disorder was the most strongly associated disorder with suicide attempts, more with multiple attempts.

Unplanned versus planned suicide attempters, precipitants, methods, and an association with mental disorders in a Korea-based community sample

BACKGROUND Studies have consistently reported that a considerable proportion of suicidal attempts are unplanned. We have performed the first direct comparison between planned and unplanned attempts including associated methods and precipitants. METHOD A total of 6510 adults, who had been randomly selected through a one-person-per-household method, completed interviews (response rate 81.7%). All were interviewed using the K-CIDI and a questionnaire for suicide. RESULTS Two hundred and eight subjects reported a suicide attempt in their lifetime, one-third of which had been unplanned. These individuals exhibited a lower level of education; however, no significant differences were found with regard to age, gender, marital and economic status. Further, 84.0% of unplanned attempters experienced previous suicidal ideation, experiencing their first attempt 1.9 years before ideation. Additionally, 94.4% of unplanned attempters had precipitants for attempts such as familial conflict and it was also found that methods such as the use of chemical agents or falling were three times more common in unplanned than planned attempters. With respect to unplanned attempters, they exhibited a significant association with alcohol use disorder, major depressive disorder, posttraumatic stress disorder, and bipolar disorder. In particular, bipolar disorder was found to be 3.5 times higher in these individuals. CONCLUSIONS Results have revealed that unplanned suicide attempters experience suicidal ideation and precipitants prior to their attempt. Further, attempts were associated with affective and alcohol use disorders. Therefore, in order to reduce the number of suicidal attempts, it may be useful to evaluate suicidal ideation concurrent to the treatment of existing mental disorders.

Prevalence, correlates, and comorbidities of adult ADHD symptoms in Korea: Results of the Korean epidemiologic catchment area study

We examined the prevalence, correlates, and comorbidities of adult attention-deficit hypersensitivity disorder (ADHD) symptoms in a Korean community using data from the National Epidemiological Survey of Psychiatric Disorders in Korea conducted in 2006. A total of 6081 subjects aged 18 to 59 years participated in this study. Diagnostic assessments were based on the Adult ADHD Self-Report Scale Screener and Composite International Diagnostic Interview administered by lay interviewers. The frequencies of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) disorders, sleep disturbances, and suicidal tendency were compared in the ADHD and non-ADHD groups. Odds ratios and significance levels were calculated. The 6 month prevalence of adult ADHD symptoms was 1.1%. Associations between ADHD symptoms and alcohol abuse/dependence, nicotine dependence, mood disorders, major depressive disorder, bipolar disorder, anxiety disorders, obsessive-compulsive disorder, post-traumatic stress disorder, social phobia, specific phobia, somatoform disorder, sleep disturbances, and suicidality were overwhelmingly positive and significant (P<0.05), after controlling for gender and age. Adult ADHD symptoms are highly associated with substance abuse, mood and anxiety disorders, somatoform disorders, sleep disturbances and suicidality, suggesting that clinicians should carefully evaluate and treat such psychiatric disorders in adults with ADHD symptoms.

Relationships of sleep duration with sociodemographic and health-related factors, psychiatric disorders and sleep disturbances in a community sample of Korean adults

The aim of this study is to examine relationships of sleep duration with sociodemographic and health‐related factors, psychiatric disorders and sleep disturbances in a nationwide sample in Korea. A total of 6510 subjects aged 18–64 years participated in this study. Logistic regression was used to calculate the odd ratios and 95% confidence intervals of the covariates, psychiatric disorders and sleep disturbances across the following sleep duration categories: 5 h or less, 6, 7, 8 and 9 h or more per day. Low levels of education, unemployment and physical illness were associated with sleeping for 5 h or less and 9 h or more. Being older and widowed/divorced/separated, high levels of physical activity, pain/discomfort, obesity and high scores on the General Health Questionnaires were associated with sleeping for 5 h or less. Female, being younger and underweight were associated with sleeping for 9 h or more. Alcohol dependence, anxiety disorder and social phobia were associated significantly with sleeping for 5 h or less and 9 h or more. Other psychiatric disorders were more common in subjects who slept for 5 h or less (e.g. alcohol use disorder, mood disorder, major depressive disorder, dysthymic disorder, obsessive‐compulsive disorder and specific phobia) or 9 h or more (e.g. post‐traumatic stress disorder). In addition, subjects who slept for 5 h or less reported more sleep disturbances than did subjects who slept for 7 h. Short or long sleep is associated with psychiatric disorders and/or sleep disturbance, therefore attention to the mental health of short or long sleepers is needed.

A nationwide survey on the prevalence and risk factors of late life depression in South Korea

OBJECTIVE This study aimed to estimate prevalence rates and risk factors of LLD among a large nationwide sample of Korean elders in South Korea. METHOD Of 8199 randomly sampled Koreans aged 65 years or more, 6018 participated (response rate=73.4%). Using the Korean version of the short form Geriatric Depression Scale (SGDS-K), we classified individual scoring 8 or 9 as having possible depression and those scoring ≥ 10 as having probable depression. RESULTS The age-, gender-, education-, and urbanicity-standardized prevalences were 10.1% (95% CI=9.3-10.8) for possible depression, 17.8% (95% CI=16.8-8.7) for probable depression, and 27.8% (95% CI=26.7-29.0) for overall depression. Poverty, living alone, low education, illiteracy, smoking, history of head trauma, and low Mini Mental Status Examination score were associated with greater risk of depression, while mild alcohol use and moderate to heavy exercise were associated with lower risk of depression. However gender difference in the risk of depression was not found. CONCLUSION LLD is decidedly common in South Korea. It was associated with various sociodemographic and clinical factors, some of which are amendable through policy actions. This study was limited by use of the SGDS-K rather than a standardized clinical interview.

Prevalence of DSM-IV major mental disorders among Korean adults: A 2006 National Epidemiologic Survey (KECA-R)

OBJECTIVES The aim of this study was to estimate the prevalence of the DSM-IV major mental disorders in the Korean population using the Korean version of Composite International Diagnostic Interview (K-CIDI). METHODS The Korean Epidemiologic Catchment Area study Replication (KECA-R) was conducted between August 2006 and April 2007. The sampling of the subjects was carried out across 12 catchment areas using a multistage, cluster sampling design. The target population included all eligible community dwelling residents aged 18-64 years. Face-to-face interviews were conducted using the K-CIDI based on the DSM-IV. RESULTS A total of 6510 participants completed the interview (response rate=81.7%). The lifetime and 12-month prevalence rates for DSM-IV major mental disorders were 29.0% and 16.9%, respectively. Those of specific disorders were as follows: (1) alcohol use disorder, 16.2% and 5.6%; (2) nicotine use disorder, 9.0% and 6.0%; (3) specific phobia, 3.8% and 3.4%; (4) major depressive disorder, 5.6% and 2.5%; and (5) generalized anxiety disorder, 1.6% and 0.8%. Additionally, data related to nicotine and alcohol use disorder revealed a very high male to female ratio. Further, mood and anxiety disorders were more prevalent in females than in males. CONCLUSION The prevalence of major mental disorders was high. In comparison with the studies performed in other countries, notable differences were observed with respect to the distribution of mental disorders in Korea.

Prevalence and Correlates of DSM-IV Mental Disorders in South Korean Adults: The Korean Epidemiologic Catchment Area Study 2011

Objective The aim of this study was to estimate the prevalence and correlates of mental disorders in Korean adults. Methods Door to door household surveys were conducted with community residents aged 18-74 years from July 19, 2011, to November 16, 2011 (n=6,022, response rate 78.7%). The sample was drawn from 12 catchment areas using a multistage cluster method. Each subject was assessed using the Korean version of the World Health Organization Composite International Diagnostic Interview (CIDI) based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Results Lifetime and 12-month prevalence estimates were as follows: alcohol use disorders, 13.4% and 4.4%, respectively; nicotine use disorders, 7.2% and 4.0%, respectively; anxiety disorders, 8.7% and 6.8%, respectively; and mood disorders, 7.5% and 3.6%, respectively. The prevalence rates of all types of DSM-IV mental disorders were 27.6% and 16.0%, respectively. Being female; young; divorced, separated, or widowed; and in a low-income group were associated with mood and anxiety disorders after adjustment for various demographic variables, whereas being male and young were associated with alcohol use disorders. Higher income was not correlated with alcohol use disorder as it had been in the 2001 survey. Conclusion The rate of depressive disorders has increased since 2001 (the first national survey), whereas that of anxiety disorders has been relatively stable. The prevalence of nicotine and alcohol use disorders has decreased, and the male-to-female ratio of those with this diagnosis has also decreased.

Illiteracy and the incidence of Alzheimer's disease in the Yonchon County survey, Korea

BACKGROUND This study aims to establish the incidence rates of Alzheimers disease (AD) and to understand the relations between illiteracy and AD in the Korean Yonchon survey cohort. METHODS A community-based, dementia-free cohort of 966 people aged 65 years and older was followed up for an average of 5.4 +/- 1.60 years to detect incident AD cases using a two-phase procedure. Age-specific incidence rates were calculated using a person-years approach with Poisson distribution confidence intervals. Data were analyzed using the Cox proportional hazards model to find the hazard ratio of illiteracy. RESULTS The participating percentage of the survivors was 86.4% and 74 subjects were diagnosed with AD. Incidence rates per 1000 person-years were 20.99 (95% CI 16.48 to 26.35) for AD. The hazard ratio of illiteracy was 1.78 (95% CI 1.08 to 2.93) adjusted for age, sex, educational level. AD developed more rapidly with aging in the illiterate group than in the literate group. CONCLUSIONS Illiteracy is associated with a higher risk of AD and the risk increases with age.

Relationships of mental disorders and weight status in the Korean adult population.

The purpose of this study was to evaluate the associations between weight status and mental disorders, including depressive disorder, anxiety disorder and alcohol use disorder. A total of nationally representative 6,510 subjects aged 18-64 yr was interviewed in face-to-face household survey. Response rate was 81.7%. Mental disorders were diagnosed using the Korean version of the Composite International Diagnostic Interview (K-CIDI). The subjects reported their heights and weights. After adjusting for age and gender, the lifetime diagnosis of depressive disorder had a significant association with only the underweight group (odds ratio [OR], 1.68, 95% confidence interval [CI], 1.19-2.38). The association between underweight and depressive disorder was the strongest for subjects with a high education level (OR, 1.75, 95% CI, 1.2-2.56), subjects with a married/cohabiting status (OR, 1.94, 95% CI, 1.17-3.22) and smokers (OR, 2.58, 95% CI, 1.33-4.98). There was no significant association between obesity and depressive disorder in Korea. But there was a significant association between the underweight group and depressive disorder. The relationship between obesity and mental disorder in a Korean population was different from that in a Western population. These results suggest that the differences of traditional cultures and races might have an important effect on the associations between the weight status and mental disorders.