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.

Hand Grip Strength, Osteoporosis, and Quality of Life in Middle-Aged and Older Adults.

Background and Objectives: Hand grip strength (HGS) and osteoporosis are known to be closely related to the health condition of the elderly, respectively. Comprehensive studies including adults over middle age were insufficient. This study aimed to investigate the relationship between HGS with osteoporosis and health-related quality of life (HRQoL) in adults aged >40 years. Materials and Methods: This cross-sectional analysis included data from 13,966 people aged >40 years between 2015 to 2018 provided by the Korea National Health and Nutrition Examination Survey. The HGS was divided into strong and weak quartiles, defined as the highest and lowest quartiles, respectively. We used the European Quality of Life Scale-Five dimensions (EQ-5D) for HRQoL. We performed multiple logistic regression and post hoc analysis to confirm the relationship between the four groups and HRQoL. Results: Osteoporotic patients with weak HGS showed the lowest EQ-5D index (0.87 ± 0.01) among all groups and had a significantly impaired HRQoL in all EQ-5D dimensions, at least 1.75 times more than healthy individuals with strong HGS (0.95 ± 0.00). Osteoporotic patients with weak HGS showed, notably, 2.68 times more impaired mobility compared to healthy individuals with strong HGS among all five dimensions of the EQ-5D. In self-care, significant sex differences in impaired HRQoL were observed (males 6.03, 2.23-16.35; females 2.51, 1.70-3.71). Conclusions: Weak HGS and the presence of osteoporosis were associated with low HRQoL, respectively. Middle-aged and older adults with both weak HGS and osteoporosis showed poorer HRQoL compared to healthy middle-aged and older adults. This suggests that HGS is a possible factor for predicting poor HRQoL in adults aged >40 years with or without osteoporosis. It is necessary to assess the risk of low HRQoL by measuring HGS and confirming whether osteoporosis is accompanied in adults over middle age.

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.

Association between a Marine Healing Program and Metabolic Syndrome Components and Mental Health Indicators.

Background and Objectives: Metabolic syndrome is a growing health concern globally, and its prevalence continues to increase. This study investigated whether a marine healing program could improve metabolic syndrome indicators and mental health in adults with a metabolic syndrome and those at risk of developing it. Materials and Methods: This study enrolled 30 participants who were assigned to either the experimental or control groups. The duration of the study was set at 4 weeks. Both groups received metabolic syndrome management education, and the experimental group additionally participated in two marine healing programs. Anthropometric indicators, biochemical indicators, and mental health indicators were collected before and after the intervention. Results: The findings indicate that the experimental group had significantly lower systolic blood pressure, triglycerides, and body weight, as well as higher levels of high-density lipoprotein (HDL-C) and uric acid. Mental health indicators (Hospital Anxiety and Depression Scale and quality of life measures) additionally showed improvement. Pre-post comparisons between the experimental group and the control group showed that the experimental group had significantly decreased by 1.05 kg in body weight, whereas the control group increased by 0.29 kg in body weight. In addition, HDL-C decreased by 0.91 mg/dL in the control group and increased by 3.7 mg/dL in the experimental group. Conclusions: Overall, these results suggest that marine healing programs could improve metabolic syndrome indicators such as body weight and HDL-C better than the control treatment.

Obesity Fact Sheet in Korea, 2021: Trends in Obesity Prevalence and Obesity-Related Comorbidity Incidence Stratified by Age from 2009 to 2019.

Background: The global public health burden of obesity has increased with socio-economic development. The Korean Society for the Study of Obesity released the 2021 Obesity Fact Sheet to address trends in obesity prevalence and comorbid conditions by different age groups. Methods: Individuals ≥20 years old who underwent a health checkup provided by the Korean National Health Insurance Service between 2009 and 2019 were included. The prevalence of obesity and abdominal obesity was standardized by age and sex based on the 2010 population and housing census. The incidence of obesity-related comorbidities was tracked from 2009 to 2019, and the incidence per 1,000 person-years was calculated using Poisson regression adjusted for age and sex. Results: Obesity and abdominal obesity prevalence has increased for the entire population over the past 11 years. Obesity prevalence has risen rapidly in individuals in their 20s and 80s compared with other age groups. Additionally, class III obesity prevalence in both men and women has significantly increased by nearly threefold. The relative risk of developing type 2 diabetes, myocardial infarction, ischemic stroke, and cancers in people with obesity or abdominal obesity is greater than in people without obesity or abdominal obesity. The relative risk was higher in young and middle-aged individuals than in the older population. Conclusion: The findings based on the 2021 Obesity Fact Sheet suggest the need to better understand obesity characteristics according to age and sex and to establish individualized treatment strategies.

Non-Alcoholic Fatty Liver Disease Defined by Fatty Liver Index and Incidence of Heart Failure in the Korean Population: A Nationwide Cohort Study.

Fatty liver index (FLI) is a simple and useful index that evaluates non-alcoholic fatty liver disease (NAFLD), particularly in large epidemiologic studies. Heart failure (HF) is becoming a burden to public health as the global trend toward an aging society continues. Thus, we investigated the effect of FLI on the incidence of HF using large cohort data from the Korean National Health Insurance health database. Methods and Results: A total of 7,958,538 subjects aged over 19 years without baseline HF (men = 4,142,264 and women = 3,816,274) were included. Anthropometric and biochemical measurements were evaluated. FLI scores were calculated and FLI ≥ 60 was considered as having NAFLD. Hazard ratios (HRs) and 95% confidence intervals (CIs) for HF incidence were analysed using multivariable time-dependent Cox proportional hazard models. During a mean follow up of 8.26 years, 17,104 participants developed HF. The FLI components associated with the incidence of HF and FLI showed a causal relationship with HF; the FLI ≥ 60 group had a higher HR for HF (HR 1.493; 95% CIs 1.41−1.581) than the FLI < 30 group. Subgroup analysis showed that fatty liver (FLI ≥ 60) with age ≥ 65 years or women displayed higher HR for HF than fatty liver with age < 65 or men, respectively. An increase in FLI score significantly increased the HR for HF except for those with a FLI score change from <30 to 30−60. Conclusion: NAFLD defined by FLI and increase in FLI score were associated with the incidence of HF. Further detailed prospective studies are needed.

Relation between Handgrip Strength and Quality of Life in Patients with Arthritis in Korea: The Korea National Health and Nutrition Examination Survey, 2015-2018.

Background and Objectives: This study aimed to investigate the relationship between handgrip strength (HGS) and quality of life (QOL) in patients diagnosed with osteoarthritis (OA) or rheumatoid arthritis (RA). Materials and Methods: We enrolled 13,966 from the Korea National Health and Nutrition Examination Survey from 2015 to 2018. All participants underwent the health-related QOL assessment using the European Quality of Life Scale-Five dimensions (EQ-5D) and measured the HGS. The weak HGS was defined as the lowest quartile. We investigated the difference in QOL between patients with arthritis and the healthy control group and evaluated the correlation between weak HGS and QOL in arthritis patients. Results: Those diagnosed with OA or RA had significantly lower QOL than healthy controls. The weak HGS was significantly correlated with lower QOL in arthritis patients. Among OA patients, those with weak HGS revealed significantly higher odds ratios for impairment in all dimensions of EQ-5D. RA patients with weak HGS had significantly higher odds ratios for impairment in dimensions of mobility, self-care, usual activity, and pain/discomfort than those with normal HGS. Conclusions: These results suggest that weak HGS is significantly associated with decreased QOL in patients with arthritis.

Association between living alone and incident type 2 diabetes among middle-aged individuals in Korea: a nationwide cohort study.

We studied the association between living alone and the risk of incident type 2 diabetes in middle-aged individuals using nationwide cohort data from the Korean population. 11,686, 677 middle-aged individuals aged 40-64 years who underwent health examinations by the Korean National Health Insurance System between 2009 and 2012 were followed up until December 31, 2015. The hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox proportional hazards regression analysis. During the median follow-up duration of 5.6 years, 393,438 individuals developed type 2 diabetes. Living alone was significantly associated with incident type 2 diabetes in all adjusted models (HR 1.08; 95% CI 1.07-1.09 in model 4). Individuals who lived alone for < 1 year and 1-7 years were associated with increased HRs of 1.07 (1.04-1.09) and 1.08 (1.07-1.09). Living alone was associated with incident type 2 diabetes in all subgroups. The association was stronger in men than in women and younger individuals than in older individuals. Living alone, even for a short duration, may be an important factor in type 2 diabetes development. Better household conditions and appropriate support to one-person households may be needed to prevent type 2 diabetes.

Anti-Obesity Effects of Artemisia annua Extract in Zucker Fatty Rats and High-Fat Diet Sprague Dawley Rats through Upregulation of Uncoupling Protein 1.

BACKGROUND: Obesity is a widespread disease and is caused mainly by excessive adipocyte differentiation and fat accumulation. Peroxisome proliferation-activated receptor γ (PPARγ) and CCAAT/enhancer-binding proteins (C/EBP) are major components for regulating adipocyte differentiation. Uncoupling protein 1 (UCP1) is a transmembrane protein that can convert white fat to brown adipose tissue. Artemisia annua L. has long been used in East Asia as an herbal drug for anti-oxidant, anti-bacterial, and anti-obesity purposes. METHODS: We investigated the effects of water extracts of A. annua (WEAA) in C3H10T1/2, a mesenchymal stem cell line, by measuring the level of intracellular fat accumulation and the expression of genes associated with adipocyte differentiation. We also evaluated anti-obesity effects of WEAA in Zucker rats, a genetic model for the study of obesity, and in Sprague Dawley rats with high-fat diet (HFD)-induced obesity. RESULTS: In this study, WEAA reduced the expression levels of PPARγ and C/EBPα in C3H10T1/2 cells, as well as the expression of enzymes that regulate fatty acid metabolism. In the Zucker fatty rat model and the HFD-induced obesity rat model, WEAA significantly decreased adipogenic differentiation and white fat accumulation between the scapulae, in contrast to the brown fat that remained unchanged between the groups. A. annua suppressed the expression of the adipocyte differentiation-promoting genes, while increasing the expression of UCP1. CONCLUSION: These results indicated that WEAA could reduce adipocyte differentiation and fat accumulation in in vitro and in vivo model systems, resulting in suppression of obesity and the occurrence of fatty liver due to a HFD.

A Randomized, Double-Blind, Placebo-Controlled, Multi-Centered Clinical Study to Evaluate the Efficacy and Safety of Artemisia annua L. Extract for Improvement of Liver Function.

Non-alcoholic fatty liver disease (NAFLD) has the potential to develop into hepatic steatosis and progress to terminal liver diseases such as cirrhosis and hepatocellular carcinoma. This human clinical study was aimed to demonstrate that SPB-201 (powdered-water extract of Artemisia annua) can improve liver function in subjects with non-alcoholic liver dysfunction at mild to moderate levels. A decrease of 271% in aspartate aminotransferase (AST) level and a significant decrease of 334% in alanine aminotransferase (ALT) level was observed in the test group as compared to the control group at the 4 weeks follow-up. In addition, after 8 weeks, decreases of 199% in AST level and 216% in ALT level were reported in the test group as compared to the control group. These results confirmed that SPB-201 intake significantly enhanced liver function and health. Moreover, the Multidimensional Fatigue Scale score of the test group decreased but that of the control group increased, implicating that SPB-201 also eliminated overall fatigue. No significant adverse events were observed among all subjects during the study. Taken together, our clinical study confirmed the excellent efficacy and safety of SPB-201 in liver function improvement, showing the possibility of SPB-201 as a functional food to restore liver dysfunction and treat liver diseases.

Body Weight Variability and the Risk of Cardiovascular Outcomes and Mortality in Patients With Type 2 Diabetes: A Nationwide Cohort Study.

OBJECTIVE: Obesity and type 2 diabetes are risk factors for cardiovascular diseases and mortality, and they commonly result in weight variabilities. We aimed to investigate the association between body weight variability and risk of major cardiovascular outcomes and mortality in individuals with type 2 diabetes using large-scale, nationwide cohort data on the Korean population. RESEARCH DESIGN AND METHODS: We enrolled 624,237 individuals with type 2 diabetes who underwent health examinations provided by the Korean National Health Insurance System between 2009 and 2010, with three or more body weight measurements within 5 years since enrollment and followed up until the end of 2017. We assessed body weight variability using four indices, including variability independent of the mean (VIM). A multivariate-adjusted Cox proportional hazards regression analysis was performed. RESULTS: During the follow-up, 15,832, 25,038, and 44,716 cases of myocardial infarction (MI), stroke, and all-cause mortality, respectively, were recorded. Body weight variability was associated with increased risks of major cardiovascular outcomes after adjusting for confounding variables. Compared with the hazard ratios (HRs) of the lowest quartile group, the HRs (95% CIs) of the highest quartile group of VIM for body weight were 1.15 (1.10-1.20), 1.22 (1.18-1.26), and 1.58 (1.53-1.62) for MI, stroke, and all-cause mortality, respectively. CONCLUSIONS: Body weight variability was associated with increased risks of MI, stroke, and all-cause mortality in patients with type 2 diabetes and may be a predictor of cardiovascular outcomes in such patients. Appropriate interventions to maintain stable weight could positively influence health outcomes in patients with type 2 diabetes.

Associations between Living Alone and Smoking and Alcohol Consumption in Korean Adults.

BACKGROUND: Recently, single-person households have increased in Korea and this trend may have potential public health implications and affect various health behaviors. This study investigated the associations between living alone and health behaviors such as smoking and alcohol consumption among Korean adults. METHODS: We used data from the 6th Korea National Health and Nutrition Examination Survey between 2013 and 2015 and a total of 17,088 adults were included. We performed a multivariable logistic regression analysis and calculated odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: Single-person households accounted for about 10% of the total participants. The proportions of currently smoking and heavy alcohol consumption were higher among individuals living alone than those living together among younger women and middle-aged and elderly men and women. In the multivariable logistic regression analysis, living alone was associated with increased odds of currently smoking compared to living together among middle-aged men and women (OR, 7.37; 95% CI, 2.33-23.32 in men and OR, 2.36; 95% CI, 1.04-5.36 in women) after adjusting for confounding variables. CONCLUSION: From this nationwide, population-based study, we found that living alone is associated with increased odds of currently smoking, especially in middle-aged people. Public health concerns may be warranted for middle-aged single-person households to reduce health risks related to smoking.

Variabilities in Weight and Waist Circumference and Risk of Myocardial Infarction, Stroke, and Mortality: A Nationwide Cohort Study.

BACKGROUND: Evidence regarding the association between variabilities in obesity measures and health outcomes is limited. We aimed to examine the association between variabilities in obesity measures and cardiovascular outcomes and all-cause mortality. METHODS: We identified 4,244,460 individuals who underwent health examination conducted by the Korean National Health Insurance Service during 2012, with ≥3 anthropometric measurements between 2009 and 2012. Variabilities in body weight (BW) and waist circumference (WC) were assessed using four indices including variability independent of the mean (VIM). We performed multivariable Cox proportional hazards regression analyses. RESULTS: During follow-up of 4.4 years, 16,095, 18,957, and 30,200 cases of myocardial infarction (MI), stroke, and all-cause mortality were recorded. Compared to individuals with the lowest quartiles, incrementally higher risks of study outcomes and those of stroke and all-cause mortality were observed among individuals in higher quartiles of VIM for BW and VIM for WC, respectively. The multivariable adjusted hazard ratios and 95% confidence intervals comparing the highest versus lowest quartile groups of VIM for BW were 1.17 (1.12 to 1.22) for MI, 1.20 (1.16 to 1.25) for stroke, and 1.66 (1.60 to 1.71) for all-cause mortality; 1.07 (1.03 to 1.12) for stroke and 1.29 (1.25 to 1.33) for all-cause mortality regarding VIM for WC. These associations were similar with respect to the other indices for variability. CONCLUSION: This study revealed positive associations between variabilities in BW and WC and cardiovascular outcomes and allcause mortality. Our findings suggest that variabilities in obesity measures are associated with adverse health outcomes in the general population.

Poor Control of Blood Glucose, Lifestyle, and Cardiometabolic Parameters in Younger Adult Patients with Type 2 Diabetes Mellitus.

This study investigated the awareness, treatment, and control of type 2 diabetes mellitus (T2DM), lifestyle factors, and cardiometabolic parameters according to age groups among patients with T2DM. Data of 1507 patients with T2DM aged ≥35 years in the Korea National Health and Nutrition Examination Survey VI (2013-2015) were analyzed. Multivariable logistic regression models were used to compare the awareness, treatment, and control rate of T2DM and lifestyle and cardiometabolic parameters according to age groups. The adjusted odds ratios (ORs) for lack of awareness about and non-treatment of T2DM, as well as poor glycemic control, were significantly increased with younger age in both men and women. ORs for heavy drinkers and current smokers also significantly increased with younger age in both men and women. The adjusted ORs for high low-density lipoprotein cholesterol (≥100 mg/dL), hypertriglyceridemia (≥150 mg/dL), and obesity significantly increased with younger age in men, but not in women. Among Korean adults with T2DM, awareness, treatment, and control rates of the condition were poorer in younger patients than in older patients. Education regarding the control of glycemia, cardiovascular risk factors, and improvement of lifestyles should be reinforced among younger-aged adults for the long-term management of T2DM.

Obesity, abdominal obesity and subsequent risk of kidney cancer: a cohort study of 23.3 million East Asians.

BACKGROUND: Limited evidence exists regarding associations between obesity and kidney cancer among Asians. We examined the associations between obesity measures and risk of kidney cancer. METHODS: We included 23,313,046 adults who underwent health examinations provided by the Korean National Health Insurance Service 2009-2012 and performed multivariable Cox proportional hazards regression analyses. RESULTS: During 5.4 years of follow-up, 18,036 cases of kidney cancer were recorded, and cumulative incidence was 0.12%. General and abdominal obesity were associated with 1.32-fold increased risk of kidney cancer compared with groups without either obesity status. Underweight individuals showed decreased adjusted hazard ratio (HR) for kidney cancer (0.76, 95% confidence interval: 0.68-0.85) compared to those with normal body mass index (BMI), while the HRs increased among individuals with BMI 23-24.9 kg/m2 (1.23, 1.18-1.28), 25-29.9 kg/m2 (1.41, 1.36-1.46) and ≥30 kg/m2 (1.77, 1.65-1.90) (P for trend < 0.001). HRs of kidney cancer increased with increasing waist circumference (WC) (P for trend < 0.001). Compared to non-obese condition, the coexistence of general and abdominal obesity increased the HR (1.45, 1.40-1.50). CONCLUSIONS: This study demonstrated positive associations of BMI and WC with kidney cancer risk. General and abdominal obesity may be risk factors of kidney cancer.

Chronic renal dysfunction, proteinuria, and risk of Parkinson's disease in the elderly.

BACKGROUND: The roles of chronic kidney disease and proteinuria in the development of Parkinson's disease have not been widely studied. The objective of this study was to examine the associations of chronic renal dysfunction and proteinuria with the risk of PD in older adults using cohort data of the whole South Korean population. METHODS: We included 3,580,435 individuals aged ≥65 years who had undergone health checkups provided by the National Health Insurance Service of South Korea between 2009 and 2012 and were followed until 2015. Multivariable Cox proportional hazards regression models were performed. RESULTS: During a mean follow-up of 5.2 ± 1.3 years, 30,813 individuals (0.86% of the total population) developed PD. Lower estimated glomerular filtration rate and a higher degree of proteinuria on a dipstick test were associated with higher incidence probability of PD (log-rank P < 0.001). In Cox regression models, chronic renal dysfunction graded by estimated glomerular filtration rate (mL/min/1.73 m2 ) was associated with increased risk of PD after adjusting for potential confounding variables; hazard ratio (95% confidence interval) was 1.13 (1.10-1.17) for estimated glomerular filtration rate 60-90, 1.36 (1.31-1.42) for estimated glomerular filtration rate 30-60, and 1.47 (1.32-1.63) for estimated glomerular filtration rate <30 (P for trend <0.001). Proteinuria ≥1+ was also associated with increased risk of PD development (hazard ratio, 1.12; 95% confidence interval, 1.06-1.18). Coexistence of chronic kidney disease and proteinuria showed an increased hazard ratio of 1.33 (95% confidence interval, 1.23-1.45) for PD occurrence. CONCLUSIONS: Our findings suggest that chronic renal dysfunction and dipstick-positive proteinuria may be independent risk factors for the development of PD in older adults. © 2019 International Parkinson and Movement Disorder Society.

Associations between Breastfeeding and Type 2 Diabetes Mellitus and Glycemic Control in Parous Women: A Nationwide, Population-Based Study.

We investigated associations between breastfeeding duration and number of children breastfed and type 2 diabetes mellitus (T2DM) and glycemic control among parous women. We performed a cross-sectional analysis of data for 9,960 parous women from the Korea National Health and Nutritional Examination Survey (2010 to 2013). Having ever breastfed was inversely associated with prevalent T2DM (adjusted odds ratio [OR], 0.60; 95% confidence interval [CI], 0.42 to 0.87). All ranges of total and average breastfeeding duration showed inverse associations with T2DM. Even short periods of breastfeeding were inversely associated with T2DM (adjusted OR, 0.61; 95% CI, 0.38 to 0.99 for a total breastfeeding duration ≤12 months; adjusted OR, 0.65; 95% CI, 0.42 to 0.99 for an average breastfeeding duration per child ≤6 months). A longer duration of breastfeeding was associated with better glycemic control in parous women with T2DM (P trend=0.004 for total breastfeeding duration; P trend <0.001 for average breastfeeding duration per child). Breastfeeding may be associated with a lower risk of T2DM and good glycemic control in parous women with T2DM. Breastfeeding may be a feasible method to prevent T2DM and improve glycemic control.

Impact of body mass index and body weight variabilities on mortality: a nationwide cohort study.

BACKGROUND/OBJECTIVES: There is limited information regarding the impact of body mass index (BMI) and body weight (BWt) variabilities on mortality. This study aimed to investigate the association between BMI, BWt variabilities and subsequent mortality in the Korean population. SUBJECTS/METHODS: This study used a representative sample cohort enrolled in the national health examination program conducted by the Korean National Health Insurance Service, and 125,391 individuals were included and followed up until 2013 (mean follow-up period = 84 months). BMI and BWt variabilities were estimated as the standard deviation (SD) and coefficient of variation (CV) of serial measurements of BMI and BWt (BMI_SD, BWt_SD, BMI_CV, and BWt_CV). Cox proportional hazard regression models were used to evaluate the all-cause and cause-specific mortality according to variability indices. RESULTS: Baseline BMI showed a non-linear association with all-cause mortality. The highest quartile (Q4) groups of variability indices were associated with increased all-cause mortality risk compared to the lowest quartile (Q1) groups after adjusting for confounding factors (hazard ratio [95% confidence interval] = 1.23 [1.11-1.37] for BMI_SD; 1.25 [1.06-1.47] for BMI_CV; 1.33 [1.20-1.48] for BWt_SD; 1.42 [1.28-1.58] for BWt_CV). The hazard ratios of all-cause mortality increased from the Q2 to the Q4 groups of variability indices, in each sex group and among individuals aged ≥40 years. Furthermore, Q4 groups of variability indices were positively associated with cause-specific mortality compared to groups with Q1-Q3 of the indices (1.28 [1.05-1.56] for BWt_SD, 1.21 [1.001-1.47] for BMI_CV, 1.29 [1.06-1.56] for BWt_CV regarding cardiovascular diseases mortality; 1.18 [1.03-1.36] for BWt_SD, 1.21 [1.06-1.39] for BMI_CV, 1.26 [1.10-1.44] for BWt_CV regarding cancer mortality). CONCLUSIONS: Our results suggest that BMI and BWt variabilities are independent risk factors for all-cause and cause-specific mortality.