Although both obesity and menopause are associated with increased risk of diabetes mellitus (DM), the association between obesity and DM according to menopausal status remains uncertain. Therefore, we conducted a study to examine the relationship between obesity and incidence of diabetes mellitus (DM) in premenopausal and postmenopausal women. Total of 926,196 premenopausal and 1,193,881 postmenopausal women who underwent health examinations from 2009 to 2014 were identified using the database of the Korean National Health Insurance Service. We compared the incidence and risk of DM according to body mass index (BMI) and waist circumference (WC) in the two groups of women. Cox proportional hazards analyses were performed to evaluate the association between the presence of obesity and risk of DM according to menopausal state. During the 7.8-year follow-up period, 37,736 (4.1%) premenopausal women and 121,102 (10.1%) postmenopausal women were diagnosed with DM. Compared to the reference group (BMI 18.5–23), a stronger association between obesity and risk of DM was observed in both pre- and postmenopausal women: multivariable-adjusted hazard ratios and 95% confidence intervals for BMI subgroups 30 were 0.62 (0.54, 0.70), 1.91 (1.85, 1.97), 3.38 (3.28, 3.47), and 6.25 (6.02, 6.48), respectively (p trend < 0.001) in premenopausal women and 0.87 (0.82, 0.92), 1.44 (1.41, 1.46), 2.00 (1.97, 2.03), and 2.96 (2.89, 3.02) in postmenopausal women (p trend < 0.001, p-interaction < 0.001). A similar trend was observed for WC. Subgroup analyses of women aged 45 to 55 also showed a stronger association with DM in premenopausal than in postmenopausal women. In conclusion, the association between obesity and DM was stronger in premenopausal women than in postmenopausal women. As estrogens are synthesized in adipose tissue by aromatization of androgens after menopause, increased estrogen levels in obese postmenopausal might have a protective effect against DM.

Background and Objectives: Muscle strength is associated with adverse mental health outcomes in adults; however, few studies have examined this association among adolescents. This study investigated the association between handgrip strength and mental health in a nationally representative sample of Korean adolescents. Methods: We performed a cross-sectional study of 3530 adolescent (12–18 years old) from the 2014–2017 Korean National Health and Nutrition Survey. Handgrip strength was defined as the maximum measurement in kilograms from the dominant hand. Adverse mental health included the presence of perceived stress, depressive mood and suicidal ideation. Logistic regression models were used with adjustment for potential confounders. Results: The mean age ± SD of the study participants was 14.9 ± 2.0 years. Girls (47.5% of participants) had poorer mental health than boys. For boys, each 1-kg increase in handgrip strength was associated with a 3% decrease in the odds of having perceived stress and depressive moods. For girls, there was a positive association between handgrip strength and perceived stress. The relationship between handgrip strength and perceived stress was dose dependent for both sexes. Conclusions: Low handgrip strength was associated with poor mental health among boys. Future research is required to validate our findings and to establish whether interventions to increase muscular strength can reduce the prevalence of perceived stress and depressive mood in boys.

Background: Non-alcoholic fatty liver disease (NAFLD) is regarded as a risk factor for type 2 diabetes mellitus (DM). Menopausal status also influences T2DM risk, where estrogen is presumed to play a protective role by decreasing insulin resistance. As such, we investigated the association between NAFLD and DM risk according to menopausal status. Objectives: We sought to examine the association between NAFLD and DM incidence in pre- and post-menopausal women. Methods: A total of 842,772 pre-menopausal and 1,074,767 post-menopausal women who underwent health examinations between 2009 and 2014 were included from the Korean National Health Insurance Service database. Multivariate Cox proportional hazard analyses were performed to evaluate the association between the risk of DM according to menopausal status and NAFLD, defined by a fatty liver index >60. Results: During the mean follow-up period (7.8 years), DM was diagnosed in 33,461 (4.0%) of pre-menopausal women and 121,102 (9.4%) post-menopausal women. A stronger association between NAFLD and the risk of DM was found in pre-menopausal women (multivariable-adjusted hazard ratio [aHR], 3.60; 95% confidence interval [CI], 3.48–3.71) than in post-menopausal women (aHR, 2.24; 95% CI, 2.21–2.28) (P-interaction < 0.01). Subgroup analyses among women aged 45 to 55 years also showed a stronger association in pre-menopausal (aHR, 3.35; 95% CI, 3.21–3.49) than in post-menopausal women (aHR, 2.83; 95% CI, 2.68–2.98) (P-interaction < 0.01). Conclusions: The association between NAFLD and DM was stronger in pre-menopausal women than in post-menopausal women. This might be due to the protective effect of estrogen, which is possibly in higher production in the peripheral fat tissue of post-menopausal women with NAFLD.

Background: This study aimed to investigate the relationship between changes in physical activity patterns following a new diagnosis of type 2 diabetes mellitus (T2DM) and the risk of developing depression.Methods: This study used comprehensive diabetes data from the National Health Insurance Service of South Korea. From this dataset, we included 254,619 individuals newly diagnosed with T2DM between 2009 and 2015 who had health examination data within 2 years before and after their diagnosis date and no prior history of depression. Physical activity levels were quantified using the metabolic equivalent of task (MET) method.Results: Compared with individuals with 0 MET-min/wk of physical activity before a new T2DM diagnosis, those who increased their activity levels to 500–999 MET-min/wk after diagnosis showed a 23% reduction in the risk of depression, while an increase to ≥1,000 MET-min/wk was associated with a 25% reduction in depression risk. Conversely, individuals with 1–499 MET-min/wk before diagnosis who became inactive after diagnosis experienced a 25% increased risk of depression. A similar trend toward increased depression risk was observed among those who reduced their physical activity from 500–999 or ≥1,000 MET-min/wk.Conclusion: Changes in physical activity levels before and after a new diagnosis of T2DM significantly influence the risk of developing depression, with increased activity reducing the risk and decreased activity elevating it. This finding underscores the importance of encouraging physical activity to support mental health in patients with newly diagnosed T2DM.