2023 Obesity Fact Sheet: Prevalence of Obesity and Abdominal Obesity in Adults, Adolescents, and Children in Korea from 2012 to 2021.

Background: The 2023 Obesity Fact Sheet aims to present an updated overview of obesity prevalence across all age groups, including children and adolescents. Methods: This study included individuals aged ≥20 years (n=16,941,423 in 2021) who underwent health checkups provided by the Korean National Health Insurance Service between 2012 and 2021. The prevalence of obesity and abdominal obesity was standardized by age and sex using data from the 2010 population and housing census. For children and adolescents (6 to 18 years) (n=884 in 2021), we used the Korea National Health and Nutrition Examination Survey (2012 to 2021), and obesity was defined by the corresponding sex- and age-specific body mass index percentile of 95th or greater based on the 2017 Korean National Growth Chart for Children and Adolescents. Results: The overall prevalence of obesity in 2021 is 38.4% (49.2% in men and 27.8% in women), which is a 1.27-fold increase from 30.2% in 2012. The prevalence of obesity has increased across all age groups, particularly among those aged 20, 30, and 80 years. The prevalence of class III obesity substantially increased from 0.35% (men) and 0.42% (women) in 2012 to 1.21% and 0.97% in 2021, with 3.46- and 2.31-fold increases, respectively. This increase was particularly pronounced in young adults. The prevalence of obesity in children and adolescents has surged from 9.7% in 2012 to 19.3% in 2021, with a greater increase among boys. Conclusion: Our study provides information on the current status of obesity prevalence based on the 2023 Obesity Fact Sheet, emphasizing the urgency of implementing timely strategies to reverse this increasing trend.

Association of Body Mass Index and Waist Circumference with Osteoarthritis among Korean Adults: A Nationwide Study.

BACKGROUND: Evidence on the association between obesity parameters, including body mass index (BMI) and waist circumference (WC), and osteoarthritis is limited. This study aimed to investigate these associations in Korean adults. METHODS: This nationwide cross-sectional study used data from 24,101 adults aged ≥19 years who participated in the Korea National Health and Nutrition Examination Survey 2016-2020. Odds ratios (ORs) and 95% confidence intervals (CIs) for osteoarthritis according to BMI and WC were analyzed using multivariable logistic regression analyses. RESULTS: The prevalence of osteoarthritis was higher in individuals with general (10.0%) and abdominal obesity (12.8%) compared with those without. Greater BMI and WC were associated with a higher prevalence (P<0.001) and risk of osteoarthritis (Model 3, P for trend <0.001). Individuals with general and abdominal obesity were associated with a 1.50-fold (OR, 1.50; 95% CI, 1.35-1.67) and 1.64-fold (OR, 1.64; 95% CI, 1.47-1.84) increased risk of osteoarthritis, compared with those without. Similar associations were observed in subgroups according to age, sex, smoking status, and presence of diabetes mellitus. The odds of osteoarthritis 1.73-fold increased (OR, 1.73; 95% CI, 1.53-1.95) in individuals with both general and abdominal obesity compared with those without any of them. CONCLUSION: Greater BMI, WC, and general and abdominal obesity were associated with an increased risk of osteoarthritis in Korean adults. Appropriate management of abdominal and general obesity may be important to reduce the risk of osteoarthritis.

Association between dental diseases and oral hygiene care and the risk of vertebral fracture: a nationwide cohort study.

Periodontal disease and increased missing teeth were associated with incident vertebral fractures. In contrast, professional dental cleaning and frequent tooth brushing, was associated with a lower risk of vertebral fracture. Better oral hygiene care attenuated the risk associated with dental diseases. PURPOSE: To investigate the association between oral health and the risk of vertebral fractures. METHODS: We included 2,532,253 individuals aged ≥40 years who underwent the Korean National Health Insurance Service health examinations in 2008 and followed up until December 31, 2017. We performed multivariable Cox proportional hazard regression analyses to evaluate the association between dental diseases and oral hygiene care and the risk of vertebral fractures. RESULTS: Over the 9.3-year median follow-up, 1.46% (n = 36,857) experienced vertebral fractures. Individuals with dental diseases had a higher risk of vertebral fracture than those without (hazard ratio [HR] 1.04, 95% confidence interval [CI]: 1.02-1.07 for periodontal diseases; 1.02, 1.00-1.05 for dental caries; 1.12, 1.05-1.20 for ≥15 missing teeth). Good oral hygiene care was associated with a lower vertebral fracture risk (HR 0.89, 95% CI: 0.86-0.91 for ≥1 time/year [vs. <1 time/year] of professional dental cleaning; 0.90, 0.87-0.93 for ≥2 times/day [vs. 0-1 time/day] of toothbrushing). The combined dental diseases was significantly associated with an increased vertebral fracture risk, whereas combined oral hygiene care was associated with further risk reduction. Better oral hygiene care reduced vertebral fracture risk associated with dental diseases (all P <0.001). CONCLUSION: Periodontal disease, dental caries, and an increased number of missing teeth were independently associated with higher risks for vertebral fractures. Conversely, improved oral hygiene care, such as personal dental cleaning and frequent tooth brushing, may modify vertebral fracture risks associated with dental disease.

Association of low muscle strength with metabolic dysfunction-associated fatty liver disease: A nationwide study.

BACKGROUND: There is limited evidence regarding the association between muscle strength and metabolic dysfunction-associated fatty liver disease (MAFLD). AIM: To investigate the association between muscle strength and MAFLD in the general population in Korea. METHODS: This nationwide representative cross-sectional study included 31649 individuals aged ≥ 19 years who participated in the Korea National Health and Nutrition Examination Survey between 2015 and 2018. Odds ratios (ORs) and 95% confidence intervals (95%CIs) for MAFLD according to sex-specific quartiles of muscle strength, defined by relative handgrip strength, were calculated using multivariable logistic regression analysis. Additionally, multivariable logistic regression analysis was used to assess the association between muscle strength and probable liver fibrosis in patients with MAFLD. RESULTS: Of all the participants, 29.3% had MAFLD. The prevalence of MAFLD was significantly higher in the lower muscle strength quartile groups for all participants, sexes, and age groups (P < 0.001). A 1.92-fold (OR = 1.92, 95%CI: 1.70-2.16) and 3.12-fold (OR = 3.12, 95%CI: 2.64-3.69) higher risk of MAFLD was observed in the lowest quartile (Q1) group than in the other groups (Q2-Q4) and the highest quartile (Q4) group, respectively. The ORs of MAFLD were significantly increased in the lower muscle strength quartile groups in a dose-dependent manner (P for trend < 0.001). These associations persisted in both sexes. An inverse association between muscle strength and the risk of MAFLD was observed in all subgroups according to age, obesity, and diabetes mellitus. In patients with MAFLD, the odds of severe liver fibrosis were higher in Q1 (OR = 1.83, 95%CI: 1.25-2.69) than in other groups (Q2-Q4). CONCLUSION: Among Korean adults, low muscle strength was associated with an increased risk of MAFLD and liver fibrosis in patients with MAFLD.

Association Between Premature Menopause and Cardiovascular Diseases and All-Cause Mortality in Korean Women.

Background Mortality from cardiovascular diseases in Asian populations is considerable. Menopause is a risk-enhancing factor for cardiovascular disease, but it is unclear whether menopause is an independent risk factor for cardiovascular disease and mortality in Asian women. Methods and Results A total of 1 159 405 postmenopausal women, who had participated in the health examinations of the Korean National Health Insurance Service in 2009, were analyzed, and their reproductive histories were taken. A multivariable Cox proportional hazard model assessed the hazard ratios (HRs) of myocardial infarction (MI), ischemic stroke, and all-cause mortality, according to the history of premature menopause and age at menopause. After an average 10-year follow-up, there were 31 606, 45 052, and 77 680 new cases of MI, ischemic stroke, and all-cause mortality, respectively. The women with premature menopause exhibited increased risks of MI (HR, 1.40 [95% CI, 1.31-1.50]), ischemic stroke (HR, 1.24 [95% CI, 1.17-1.31]), and all-cause mortality (HR, 1.19 [95% CI, 1.14-1.24]) when compared with women with menopause aged ≥50 years. The highest risk was evident with menopause between the ages of 30 and 34 years (HR for MI, 1.52 [95% CI, 1.30-1.78]; HR for ischemic stroke, 1.29 [95% CI, 1.12-1.48]; HR for all-cause mortality, 1.33 [95% CI, 1.20-1.47]) when compared with women with menopause aged ≥50 years. Conclusions Earlier age at menopause was associated with increased risks for MI, ischemic stroke, and all-cause mortality. Future guidelines and risk assessment tools should consider menopause as an independent risk factor of cardiovascular disease in Korean women.

Differential Impact of Obesity on the Risk of Diabetes Development in Two Age Groups: Analysis from the National Health Screening Program.

BACKGRUOUND: The effect of obesity on the development of type 2 diabetes mellitus (DM) in different age groups remains unclear. We assessed the impact of obesity on the development of DM for two age groups (40-year-old, middle age; 66-year-old, older adults) in the Korean population. METHODS: We analyzed Korean National Health Insurance Service data of 4,145,321 Korean adults with 40- and 66-year-old age without DM, between 2009 and 2014. Participants were followed up until 2017 or until the diagnosis of DM. We assessed the risk of DM based on the body mass index and waist circumference of the participants. Multiple confounding factors were adjusted. RESULTS: The median follow-up duration was 5.6 years. The association of general and abdominal obesity with the risk of DM development was stronger in the 40-year-old group (general obesity: hazard ratio [HR], 3.566, 95% confidence interval [CI], 3.512 to 3.622; abdominal obesity: HR, 3.231; 95% CI, 3.184 to 3.278) than in the 66-year-old group (general obesity: HR, 1.739; 95% CI, 1.719 to 1.759; abdominal obesity: HR, 1.799; 95% CI, 1.778 to 1.820). In the 66-year-old group, abdominal obesity had a stronger association with the development of DM as compared to general obesity. In the 40-year-old group, general obesity had a stronger association with the risk of DM development than abdominal obesity. CONCLUSION: The influence of general and abdominal obesity on the development of DM differed according to age. In older adults, abdominal obesity had a stronger association with DM development than general obesity.

Associations between obesity parameters and hyperuricemia by sex, age, and diabetes mellitus: A nationwide study in Korea.

OBJECTIVE: We investigated the associations between obesity parameters and the risk of hyperuricemia among Korean adults by sex, age, and diabetes mellitus status. METHODS: This study analyzed data from 17,753 adults from the Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2018. Multivariable logistic regression analyses were conducted to examine the associations of body mass index (BMI), waist circumference (WC), and general and abdominal obesity with the risk of hyperuricemia (serum uric acid ≥7.0 mg/dL in men and ≥6.0 mg/dL in women). RESULTS: Of all the participants, 12.7% (n = 2256) had hyperuricemia. The age-adjusted mean serum uric acid levels increased significantly with increasing BMI and WC (P for trend <0.001). The adjusted odds ratios (ORs) of hyperuricemia increased as BMI and WC increased in both sexes (P for trend <0.001). General (OR 1.98, 95% confidence interval [CI]: 1.69-2.32) and abdominal (OR 2.21, 95% CI: 1.89-2.58) obesity in men and general (OR 3.26, 95% CI: 2.60-4.09) and abdominal (OR 3.43, 95% CI: 2.69-4.37) obesity in women were associated with higher risks of hyperuricemia. These associations were prominent in women. The association between abdominal obesity and hyperuricemia persisted after additional adjustments for BMI in both sexes. Significant interactions were observed in younger adults and individuals without diabetes mellitus. CONCLUSION: Increased BMI and WC, and general and abdominal obesity, may be important risk factors for hyperuricemia in both sexes. Women, young adults, and individuals without diabetes mellitus require particular attention to prevent obesity and hyperuricemia.

Association between Dental Diseases and Oral Hygiene Care and the Risk of Dementia: A Retrospective Cohort Study.

OBJECTIVES: To investigate the associations of dental diseases and oral hygiene care with the risk of dementia. DESIGN: Retrospective longitudinal cohort study. SETTING AND PARTICIPANTS: We conducted a population-based study of individuals in the Korean National Health Insurance System. A total of 2,555,618 participants who underwent cardiovascular and dental screenings in 2008 were included. METHODS: Dental diseases including periodontal diseases, dental caries, and tooth loss were assessed by dentists. Information on oral hygiene care, including professional dental cleaning and the frequency of tooth brushing, was collected using a self-administered questionnaire. Study outcomes were all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VaD). RESULTS: Periodontal diseases [adjusted hazard ratio (aHR) 1.07, 95% CI 1.04-1.09], dental caries (aHR 1.03, 95% CI 1.00-1.05), and 8-14 missing teeth (aHR 1.07, 95% CI 1.02-1.12) were associated with an increased risk of all-cause dementia. In contrast, either professional dental cleaning or frequent tooth brushing were associated with decreased risks of all-cause dementia (aHR 0.91, 95% CI 0.89-0.93 each; aHR 0.83, 95% CI 0.80-0.86 for both). The increased risks by dental diseases were reduced by oral hygiene care: periodontal diseases with professional dental cleaning (aHR 0.94, 95% CI 0.91-0.98) or tooth brushing ≥2 times/day (aHR 0.97, 95% CI 0.94-1.00) and 1 to 7 missing teeth with professional dental cleaning (aHR 0.94, 95% CI 0.89-0.98) or tooth brushing ≥2 times/day (aHR 0.92, 95% CI 0.89-0.95). Consistent results were noted for AD and VaD and in various subgroup analyses. CONCLUSION AND IMPLICATIONS: Periodontal disease, dental caries, and a high number of missing teeth were independently associated with a higher risk of dementia. Conversely, improved oral hygiene care, such as professional dental cleaning and frequent tooth brushing, may modify the risk of dementia associated with dental diseases.

Association of Sustained Low or High Income and Income Changes With Risk of Incident Type 2 Diabetes Among Individuals Aged 30 to 64 Years.

Importance: Evidence of the association between income fluctuation and risk of type 2 diabetes (T2D) is scarce. Objective: To investigate whether sustained low or high income and income changes are associated with incidence of T2D. Design, Setting, and Participants: In this population-based cohort study, more than 7.8 million adults without T2D aged 30 to 64 years from a nationally representative sample from the Korean Health Insurance Service database were enrolled in 2012 and followed up to 2019 (median follow-up, 6.3 years [IQR, 6.1-6.6 years]). Exposures: Twenty quantiles of monthly health insurance premiums determined income levels. Income quartiles were annually analyzed from 2008 to 2012. Beneficiaries of the Medical Aid Program were regarded as those with very low income. A decrease in income was indicated as a reduction of 25% or more in income compared with income in the previous year. Main Outcomes and Measures: The primary outcome was incident T2D based on the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes E11 to E14, 1 or more claims of antidiabetic medication, or a fasting glucose level of 126 mg/dL or higher. Multivariable Cox proportional hazards models were used to assess the association of low- or high-income status and income changes with incidence of T2D. Results: Of 7 821 227 participants (mean [SD] age, 46.4 [9.3] years; 54.9% men), 359 931 (4.6%) developed T2D at least 1 year after enrollment. Individuals who repeatedly experienced low and very low income for 5 years showed 22% (hazard ratio [HR], 1.22 [95% CI, 1.21-1.23]) and 57% (1.57 [95% CI, 1.53-1.62]) higher T2D risk compared with those who never experienced low and very low income, respectively. In contrast, individuals who were repeatedly in high-income quartiles showed lower T2D risk compared with those who never experienced high income (HR, 0.86 [95% CI, 0.85-0.86]). The number of income decreases was associated with elevated T2D risk (≥2 vs 0 income decreases: HR, 1.08 [95% CI, 1.06-1.11]; P < .001 for trend). When income quartile status was compared between 2008 and 2012, individuals who experienced an income increase had lowered T2D risk, while those who experienced an income decrease had elevated T2D risk in each income quartile group. Conclusions and Relevance: This cohort study found that individuals who experienced sustained low-income status or an income decrease had elevated T2D risk, while those who had sustained high-income status or an income increase had lowered T2D risk.

Bone Mineral Density and the Risk of Parkinson's Disease in Postmenopausal Women.

BACKGROUND: Whether bone mineral density (BMD) is related to the risk of Parkinson's disease (PD) is unclear. OBJECTIVES: The objective of this study was to examine the association between BMD status and incident PD in postmenopausal women. METHODS: We retrospectively examined a nationwide cohort of 272,604 women aged 66 years who participated in the 2009-2012 Korean national health screening for transitional ages. BMD was evaluated using dual-energy X-ray absorptiometry of the central bones. The use of antiosteoporosis medications (AOMs) was assessed. We performed multivariable Cox proportional hazards regression to evaluate the association between BMD and PD risk by calculating hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: During the median follow-up of 7.7 years, 2,884 (1.1%) incident PD cases developed. After adjusting for confounding factors, lower BMD was associated with an increased risk of PD (P for trend <0.001). Individuals with osteoporosis had a 1.40-fold higher HR (1.40, 95% CI: 1.25-1.56) than those with a normal BMD. Sensitivity analyses suggested the associations robust to longer lag periods and further adjustment. These associations were prominent in individuals without AOM use before or after enrollment (P for interaction = 0.031 and 0.014). Increased risks of PD in individuals with osteopenia and osteoporosis who did not use AOMs were attenuated by the medication use during the follow-up period, regardless of previous AOM use. CONCLUSIONS: Lower postmenopausal BMD and osteoporosis were associated with an increased risk of PD. In addition, this association could be mitigated using AOMs. Proper management of BMD in postmenopausal women may help prevent PD. © 2023 International Parkinson and Movement Disorder Society.

Association of Dental Diseases and Oral Hygiene Care With the Risk of Heart Failure in Patients With Type 2 Diabetes: A Nationwide Cohort Study.

Background To evaluate the association of dental diseases and oral hygiene care with incidence of heart failure (HF) among patients with type 2 diabetes. Methods and Results This study included 173 927 patients with type 2 diabetes aged ≥40 years, who underwent Korean National Health Insurance Service health examinations in 2008 and were followed up until the end of 2017. Hazard ratios (HRs) and 95% CIs for HF were estimated using multivariable Cox proportional hazards regression analysis. During a median follow-up of 9.3 years, 1.94% of participants developed HF. An increased number of missing teeth was associated with a higher risk of HF (P<0.001). HRs of HF increased among individuals with ≥15 missing teeth (HR, 1.37 [95% CI, 1.14-1.64]) compared with those without missing teeth. Decreased risk of HF was observed in individuals with ≥1 time/year of professional dental cleaning (HR, 0.93 [95% CI, 0.87-0.99]) and in those with ≥2 times/d of toothbrushing (HR, 0.90 [95% CI, 0.82-0.98]) compared with those without these practices. While combined presence of missing teeth and periodontal disease (P=0.004) or dental caries (P=0.007) increased HF risk, combined oral hygiene care was associated with further HF risk reduction (P=0.024). Better oral hygiene care was associated with decreased HF risk, even as the number of missing teeth increased (P<0.001). Conclusions Among patients with type 2 diabetes, dental diseases and oral hygiene care are important determinants of HF development. Dental disease management and good oral care may prevent HF in patients with type 2 diabetes.

Weight Gain, Comorbidities, and Its Associated Factors Among Korean Adults.

BACKGROUND: Weight gain in adults is associated with an increased risk of obesity-related diseases and high healthcare costs. However, there have been limited studies on weight gain in Asians. This study investigated the prevalence, comorbidities, and associated factors of weight gain in the Korean population. METHODS: This is a cross-sectional study of Korean adults aged 19-64 years who participated in the Korea National Health and Nutritional Examination Survey 2016-2019. We used data from 15,514 adults (subjects 1) to analyze the prevalence of weight gain. Finally, after excluding adults with suspicious debilitating conditions among them, 11,477 adults (subjects 2) were used to analyze comorbidities and associated factors. Weight changes and lifestyle factors were assessed using a self-report questionnaire. We analyzed odds ratios and 95% confidence intervals using multivariable logistic regression analysis to examine factors associated with weight gain. RESULTS: The overall prevalence of weight gain was 25.7% in men and 31.3% in women and decreased significantly with age in both sexes. Weight gain of ≥ 6 kg was evident in 10.5% of men and 9.8% of women and was more pronounced with a higher baseline body mass index (BMI). Most metabolic comorbidities worsened the greater the weight gain. Young age was the strongest associated factor for weight gain. Other factors associated with weight gain were being unmarried, blue-collar job, lower income, and alcohol consumption in men; being married in women; smoking and skipping breakfast in both sexes. CONCLUSION: Weight gain was much more pronounced in younger adults and at a higher baseline BMI in both sexes. Public education and health policies to prevent unnecessary weight gain should be strengthened by considering the associated harmful factors in Korean adults.

Evaluation and Treatment of Obesity and Its Comorbidities: 2022 Update of Clinical Practice Guidelines for Obesity by the Korean Society for the Study of Obesity.

The goal of the 8th edition of the Clinical Practice Guidelines for Obesity is to help primary care physician provide safe, effective care to patients with obesity by offering evidence-based recommendations to improve the quality of treatment. The Committee for Clinical Practice Guidelines comprised individuals with multidisciplinary expertise in obesity management. A steering board of seven experts oversaw the entire project. Recommendations were developed as the answers to key questions formulated in patient/problem, intervention, comparison, outcomes (PICO) format. Guidelines underwent multi-level review and cross-checking and received endorsement from relevant scientific societies. This edition of the guidelines includes criteria for diagnosing obesity, abdominal obesity, and metabolic syndrome; evaluation of obesity and its complications; weight loss goals; and treatment options such as diet, exercise, behavioral therapy, pharmacotherapy, and bariatric and metabolic surgery for Korean people with obesity. Compared to the previous edition of the guidelines, the current edition includes five new topics to keep up with the constantly evolving field of obesity: diagnosis of obesity, obesity in women, obesity in patients with mental illness, weight maintenance after weight loss, and the use of information and communication technology-based interventions for obesity treatment. This edition of the guidelines features has improved organization, more clearly linking key questions in PICO format to recommendations and key references. We are confident that these new Clinical Practice Guidelines for Obesity will be a valuable resource for all healthcare professionals as they describe the most current and evidence-based treatment options for obesity in a well-organized format.

Body mass index, waist circumference and cardiovascular diseases in transitional ages (40 and 66 years).

BACKGROUND: There is lack of data on effect modification by age on the association between body mass index (BMI) or waist circumference (WC) and cardiovascular diseases (CVDs). We aimed to investigate the impact of BMI and WC on incident CVDs in individuals aged 40 and 66 years. METHODS: Overall, 2 430 510 participants who underwent a national health screening for transitional ages provided by the Korean National Health Insurance Service between 2009 and 2012 were included. The adjusted hazard ratios and 95% confidence intervals for myocardial infarction (MI), ischaemic stroke and CVDs as a composite outcome of MI and ischaemic stroke were calculated using multivariable Cox proportional hazard regression analysis. RESULTS: During a mean follow-up of 7.7 years, 24 884 MI and 29 415 ischaemic stroke events occurred. Among participants aged 40 years, there was a J-shaped association of BMI with incident CVDs, MI and ischaemic stroke with nadir at BMI 18.5-22.9 kg/m2 (P for trend < 0.001 for all). Among those aged 66 years, there were significant U-shaped associations of BMI with CVDs and MI with nadir at a BMI of 23.0-24.9 kg/m2 (P for trend 0.013 and 0.017, respectively). WC was linearly associated with all study outcomes in both age groups (P for trend < 0.001). The impact of general and abdominal obesity on both study outcomes was more prominent in those aged 40 years than in those aged 66 years (P for interaction < 0.001). CONCLUSIONS: To prevent cardiovascular risk, weight loss intervention should be cautiously implemented and individualized according to age. The maintenance of muscle mass may be essential in managing weight loss particularly in older population.

Association between metabolic syndrome and mortality in patients with COVID-19: A nationwide cohort study.

OBJECTIVES: We investigated the association between metabolic syndrome (MetS) and mortality among coronavirus disease 2019 (COVID-19) patients in Korea. METHODS: We analyzed 3876 individuals aged ≥ 20 years who were confirmed with COVID-19 from January 1 to June 4, 2020 based on the Korea National Health Insurance Service (NHIS)-COVID-19 database and had undergone health examination by NHIS between 2015 and 2017. Multivariable Cox proportional hazard regression analyses were performed. RESULTS: Of total participants, the prevalence of MetS was 21.0% (n = 815). During 58.6 days of mean follow-up, 3.1 % (n = 120) of the participants died. Compared to individuals without MetS, COVID-19 patients with MetS had a significantly increased mortality risk after adjusting for confounders in total participants (hazard ratio [HR]: 1.68, 95 % confidence interval [CI]: 1.14-2.47) and women (HR: 2.41, 95 % CI: 1.17-4.96). A low high-density lipoprotein cholesterol level in total participants (HR: 1.63, 95 % CI: 1.12-2.37) and hyperglycemia in women (HR: 1.97, 95 % CI: 1.01-3.84) was associated with higher mortality risk. The mortality risk increased as the number of MetS components increased among total participants and women (P for trend = 0.009 and 0.016, respectively). In addition, MetS groups had higher mortality risk in aged ≥ 60 years (HR: 1.60, 95 % CI: 1.07-2.39), and never-smokers (2.08, 1.21-3.59). CONCLUSIONS: The presence of MetS and greater number of its components were associated with increased mortality risks particularly in female patients with COVID-19. Managing MetS may contribute to better outcomes of COVID-19.

Age at menopause and risk of heart failure and atrial fibrillation: a nationwide cohort study.

AIMS: This study aimed to examine the association of premature menopause and age at menopause with the risk of heart failure (HF) and atrial fibrillation (AF). METHODS AND RESULTS: A total of 1 401 175 postmenopausal women, who had undergone health examination provided by the Korean National Health Insurance Service, were included, and their reproductive histories were collected. Multivariable Cox proportional hazard models were performed to determine the hazard ratios (HRs) and 95% confidence intervals (CIs) of incident HF and AF, according to the history of premature menopause and age at menopause. At a mean follow-up of 9.1 years, there were 42 699 (3.0%) and 44 834 (3.2%) new cases of HF and AF, respectively. Women with history of premature menopause had an increased risk of HF (HR: 1.33, 95% CI: 1.26-1.40) and AF (HR: 1.09, 95% CI: 1.02-1.16), compared to women without the history. Compared with women aged ≥50 years at menopause, those aged 45-49, 40-44, and <40 years at menopause showed a significantly increased trend in HRs for the incident risk of both HF and AF (P for trend <0.001). The robustness of the results of a series of sensitivity analyses further strengthens the main findings. CONCLUSION: Our findings suggest that postmenopausal women with a history of premature menopause or early menopausal age may have an increased risk of HF and AF. These reproductive factors need to be considered for preventing the future risk of HF and AF.

COVID-19 and related social distancing measures induce significant metabolic complications without prominent weight gain in Korean adults.

Background: This study using multi-center health examination data from Korean adults was conducted to confirm changes in weight, and their related cardiometabolic parameters, before and after strengthening of social distancing regulations. Methods: A retrospective cohort study was conducted using health check-up data from 13 university hospitals. The study period was from January 2018 to July 2020. To examine the effect of systematic social distancing measures, participants who underwent a health check-up (Visit 3) between July 2020 and July 2021 (during full scale social distancing), and had undergone two previous health check-ups (Visits 1 and 2) between January 2018 and June 2020 (before social distancing), were selected. In total, data from 7,875 participants were analyzed. Linear mixed-effect models were used to calculate estimates of anthropometric indices and metabolic markers measured on Visits 2 and 3, compared with measurements from Visit 1. Results: There were no significant differences in body weight, body mass index, waist circumference, and body composition on Visit 3 than on Visits 1 and 2. However, the odds of metabolic syndrome and its components, including hypertension, high glucose, diabetes, hypercholesterolemia, hypertriglyceridemia, hyper-non-high-density lipoprotein cholesterolemia, and dyslipidemia were significantly higher on Visit 3 than on Visits 1 and 2. The increase in metabolic complications was marked, particularly in relatively young adults who visited health check-up centers located in the capital area. Conclusion: Metabolic syndrome and its components were significantly worse after high level social distancing, although there were no significant increases in anthropometric indices and body fat levels. Healthcare providers need to prevent and manage worsening of metabolic parameters in subpopulations prone to be more sedentary and eat unhealthy food during the COVID-19 pandemic and associated social distancing measures.

Fatty Liver Change in Korean Adults in a Systematic Social Distancing System Amid the COVID-19 Pandemic: A Multicenter Analysis.

In response to the COVID-19 pandemic, the Korean government implemented policies including the systematic social distancing (SSD) system which started on 28 June 2020. The present study investigated the development and aggravation of fatty liver measured using ultrasonography during the transition period (from pre-SSD to SSD) compared to the fatty liver changes during the pre-SSD period. Changes in fatty liver and liver enzymes were assessed in different groups stratified by alcohol consumption. Our retrospective cohort analysis included 5668 participants who underwent health checkups at 13 university hospitals during the SSD period and two or more checkups before the SSD period. Fatty liver developed and aggravated more in the transition period (13.6% development and 12.0% aggravation) than in the pre-SSD period (10.8% development and 10.1% aggravation) in the alcohol consumption group. This finding was more prominent in women than in men. Abnormal alanine transaminase levels were more often developed in the transition period than in the pre-SSD period, especially in men (11.1% vs. 8.6% in each period). In conclusion, the SSD system may contribute to fatty liver changes in individuals who regularly consume alcohol. Further research of the post-pandemic period is needed to assess long-term changes in fatty liver disease.

Body weight variability and the risk of dementia in patients with type 2 diabetes mellitus: A nationwide cohort study in Korea.

AIMS: This study aimed to examine the association between body weight variability and dementia risk using a large-scale cohort data of Korean patients with type 2 diabetes mellitus (T2DM). METHODS: A population-based cohort of 1,206,764 individuals with T2DM aged ≥ 40 years who underwent ≥ 3 Korean national health screenings were followed up until the end of 2019. Body weight variability was assessed using variability independent of the mean (VIM). A multivariate Cox proportional hazard regression was performed with calculating hazard ratios (HRs) with 95 % confidence intervals (CIs) of dementia incidence. RESULTS: During a median follow-up of 7.9 years, 162,615 (13.4 %) individuals developed dementia. Individuals with greater body weight variability tended to be associated with higher risk of all types of dementia (P for trend < 0.001). Individuals in the highest quartile of VIM showed 26 % (HR: 1.26, 95 % CI: 1.24-1.28), 33 % (HR: 1.33, 95 % CI: 1.30-1.36) and 28 % (HR: 1.28, 95 % CI: 1.23-1.33) higher risk for all-cause dementia, Alzheimer's disease, and vascular dementia, compared with those in the lowest quartile. These associations persisted in all body mass index categories (P for trend < 0.001). CONCLUSIONS: Maintaining an appropriate body weight may help mitigate dementia risk in patients with T2DM.

Waist circumference and risk of Parkinson's disease.

Although many studies support the association of obesity with neurodegenerative diseases, such as Parkinson's disease (PD), there are limited data regarding the association between abdominal obesity and PD, with mixed findings. The aim of this study was to examine the association of waist circumference (WC) with the risk of PD incidence. We retrospectively analyzed a large-scale nationwide cohort of 6,925,646 individuals aged ≥40 years who underwent the Korean National Health Screening during 2009. We performed multivariable Cox proportional hazards regression to evaluate the association of WC and abdominal obesity with PD risk and calculated hazard ratios (HRs) with 95% confidence intervals (CIs) of PD incidence. During a median follow-up period of 8.35 years, 33,300 cases of PD developed. PD incidence was positively associated with increases in WC (P for trend < 0.001). The risk of PD incidence tended to elevate as WC increased (P for trend < 0.001), indicating that the adjusted HRs of PD incidence in the highest WC group versus the reference group was 1.16 (95% CI, 1.10-1.23), whereas it was 0.91 (95% CI 0.84-0.98) in the lowest WC group. Individuals with abdominal obesity were significantly associated with an increased PD risk (HR 1.10, 95% CI: 1.07-1.13). These associations persisted even after adjustment for body mass index and stratification by sex. Even among non-obese individuals, abdominal obesity was associated with a higher PD risk (adjusted HR 1.13, 95% CI: 1.09-1.18). Taken together, higher WC and abdominal obesity were associated with increased PD risk. Even in non-obese individuals, abdominal obesity was associated with an increased PD risk.