Association of nonalcoholic fatty liver disease with new-onset atrial fibrillation stratified by age groups.

BACKGROUND: The association between nonalcoholic fatty liver disease (NAFLD) and atrial fibrillation (AF) has been inconsistent, and the impact of hepatic fibrosis on this relationship remains uncertain. We investigated the association between NAFLD and the risk of new-onset AF across different age groups. METHODS: A total of 3,179,582 participants from the 2009 Korean National Health Screening Program were divided into five groups based on NAFLD status: no NAFLD (fatty liver index [FLI] < 30); grade 1 NAFLD without advanced fibrosis (FLI 30-59 & BARD < 2); grade 1 NAFLD with advanced fibrosis (FLI 30-59 & BARD ≥ 2); grade 2 NAFLD without advanced fibrosis (FLI ≥ 60 & BARD < 2); and grade 2 NAFLD with advanced fibrosis (FLI ≥ 60 & BARD ≥ 2). The primary outcome was incident AF. RESULTS: During the median follow-up of 9.3 years, 62,542 patients were diagnosed with new-onset AF. In the age- and sex-adjusted model, the risk of new-onset AF increased across NAFLD grades and fibrosis categories: grade 1 NAFLD without advanced fibrosis (hazard ratio [HR] 1.120, 95% confidence interval [CI]: 1.081-1.161); grade 1 NAFLD with advanced fibrosis (HR 1.275, 95% CI 1.251-1.300); grade 2 NAFLD without advanced fibrosis (HR 1.305, 95% CI: 1.252-1.360); and grade 2 NAFLD with advanced fibrosis (HR 1.627, 95% CI: 1.586-1.670). In the multivariate model, the excess risk of AF in patients with NAFLD and advanced fibrosis remained significant, even in participants aged 20-39 years. CONCLUSION: Patients with NAFLD had a higher risk of new-onset AF, which increased progressively with NAFLD severity, particularly in those aged 20-29 years.

Risk Factors for Abdominal Aortic Aneurysm in Patients With Diabetes.

OBJECTIVE: Although diabetes has been shown to be negatively associated with development of abdominal aortic aneurysm (AAA), patients with diabetes may still develop aneurysms. In this study we examined risk factors for development of AAA in patients with diabetes. METHODS: Adults over 50 years with diabetes who underwent health screening between 2009 and 2012 were followed for incident AAA until December 31, 2019. Cox proportional hazard regression models were used to calculate multivariate hazard ratios (HR) and 95% confidence intervals (CI) for risk factors associated with AAA. RESULTS: Among 1,913,066 participants (55.3% men), 6,996 AAA cases were identified during a mean follow-up of 7.7 years. Increased AAA risk was observed for age ≥ 65 years (HR 2.69, 95% CI 2.55-2.83), men (HR 1.81, 95% CI 1.69-1.94), smoking (ex-smoker ≥ 20 pack-years, HR 1.75, 95% CI 1.61-1.89; current smoker < 20 pack-years, HR 1.76, 95% CI 1.59-1.94; current smoker ≥ 20 pack-years, HR 2.40, 95% CI 2.23-2.59), abdominal obesity (HR 1.30, 95% CI 1.23-1.38), and comorbidities: hypertension (HR 1.63, 95% CI 1.53-1.73), dyslipidemia (HR 1.35, 95% CI 1.29-1.42), chronic kidney disease (HR 1.52, 95% CI 1.44-1.61), cardiovascular disease (HR 1.71, 95% CI 1.58-1.86). Heavy (HR 0.67, 95% CI 0.61-0.74) and mild alcohol consumption (HR 0.78, 95% CI 0.74-0.83), overweight (HR 0.87, 95% CI 0.81-0.93) and obesity (HR 0.81, 95% CI 0.75-0.87), longer diabetes duration (≥ 5 years: HR 0.74, 95% CI 0.70-0.78), and using ≥ 3 oral hypoglycemic agents (HR 0.84, 95% CI 0.79-0.90) were associated with decreased AAA risk, while insulin use was associated with a marginally increased risk (HR 1.09, 95% CI 1.00-1.18). Among the oral hypoglycemic agents, metformin (HR 0.95, 95% CI 0.90-1.00), thiazolidinedione (HR 0.87, 95% CI 0.79-0.97), and sulfonylurea (HR 0.88, 95% CI 0.83-0.93) were associated with decreased risk of AAA. CONCLUSIONS: Although diabetes is associated with decreased AAA risk, those with comorbid cardiometabolic diseases, abdominal obesity, and smoking history should be aware of increased AAA risk. Further studies are warranted to verify the potential use of oral hypoglycemic agents for reducing AAA risk.

The effect of smoking on nontuberculous mycobacterial pulmonary disease and tuberculosis: a nationwide retrospective cohort study.

Although smoking is an established risk factor for Mycobacterial infection, the association between smoking and nontuberculous mycobacterial pulmonary disease (NTM-PD) remains unclear. We evaluated the association between smoking and NTM-PD and tuberculosis (TB) using a population-based South Korean nationwide cohort. Using the Korean National Health Insurance Database, we screened individuals over 20 years of age who underwent the national health screening program in 2009. Out of 3,774,308 eligible populations, we identified 2,964 and 26,112 cases of newly developed NTM-PD and TB, respectively. We used multivariate Cox proportional hazards models to estimate the adjusted hazard ratios (aHRs) of risk factors for NTM-PD and TB. The incidence rates for developing NTM-PD and TB were 0.08 and 0.68 per 1,000 person-years, respectively. Current smokers (aHR 0.63, 95% confidence interval [CI] 0.56-0.71) and current heavy smokers (≥ 20 pack-years, aHR 0.74, 95% CI 0.63-0.86) were at lower risk for NTM-PD development than never smokers. On the contrary, current smokers (aHR 1.19, 95% CI 1.15-1.23) and current heavy smokers (aHR 1.27, 95% CI 1.22-1.33) had a higher risk for TB development than never smokers. These trends were augmented if individuals started smoking before age 20 years. In subgroup analyses stratified by age, these trends were prominent in the 40-64 years age range. Current smoking was associated with a decreased risk of NTM-PD and increased risk of TB. These risks were augmented by early smoking initiation and in the middle age population.

Different Associations between Lipid Levels and Risk for Heart Failure according to Diabetes Progression.

Background: The relationship between circulating lipid levels and the risk for heart failure (HF) is controversial. We aimed to examine this association, and whether it is modified by the duration of diabetes or treatment regimens in people with type 2 diabetes mellitus. Methods: Individuals (n=2,439,978) who underwent health examinations in 2015 to 2016 were identified from the Korean National Health Information Database. Subjects were categorized according to the duration of diabetes (new-onset, <5, 5-10, or ≥10 years) and number of antidiabetic medications. Incident HF was defined according to the International Classification of Diseases, 10th Revision (ICD-10) code I50 as the primary diagnosis during hospitalization. The risk for HF was estimated using multivariate Cox proportional hazard analysis. Results: During a median follow-up of 4.0 years, 151,624 cases of HF occurred. An inverse association between low-density lipoprotein cholesterol (LDL-C) levels and incident HF was observed in the new-onset diabetes group, with an approximately 25% lower risk in those with LDL-C levels of 100-129, 130-159, and ≥160 mg/dL, compared to those with levels <70 mg/dL. However, J-shaped associations were noted in the long-standing diabetes group, with a 16% higher risk in those with LDL-C level ≥160 mg/dL, compared to those with levels <70 mg/dL. Similar patterns were observed in the relationship between total cholesterol or non-high-density lipoprotein cholesterol and the risk for HF, and when subjects were grouped according to the number of antidiabetic medications instead of diabetes duration. Conclusion: Different associations between lipid levels and the risk for HF were noted according to disease progression status among individuals with diabetes.

Lifestyle Behaviors in Patients With Gastric Cancer: Continuous Need for Alcohol Abstinence and Muscle Strength Training Education.

PURPOSE: This study was performed to assess the lifestyle-related behaviors of patients with gastric cancer (GC) and to investigate the associations between the time since GC diagnosis and these behaviors. MATERIALS AND METHODS: This study included 29,478 adults (including 338 patients with GC) aged ≥ 40 years who participated in the Korea National Health and Nutrition Examination Survey 2014-2021. Multiple logistic regression analysis explored the associations between the time since GC diagnosis (patients diagnosed with GC less than 5 years ago [<5 years group] and those diagnosed with GC 5 or more than years ago [≥5 years group]) and lifestyle factors. Subgroup analyses were conducted based on age and sex. RESULTS: The current smoking rate was not lower in the GC group than in the healthy group, regardless of time since diagnosis. Compared to the healthy controls, monthly alcohol intake was lower in the <5 years group (odds ratio [OR], 0.450; 95% confidence interval [CI], 0.275-0.736). The ≥5 years group showed a lower rate of strength training (OR, 0.548; CI, 0.359-0.838), compared with the healthy control group. Subgroup analysis focusing on the ≥5 years group revealed a significantly lower rate of strength training, particularly in patients aged ≥65 years and male patients (OR, 0.519 and 0.553; CI, 0.302-0.890 and 0.340-0.901, respectively). CONCLUSIONS: Clinicians should continue educating patients on lifestyle behavior modifications, particularly alcohol abstinence, even beyond 5 years after GC diagnosis. Education on strength training is especially important for patients ≥65 years or male patients.

Low household income increases risks for chronic obstructive pulmonary disease in young population: a nationwide retrospective cohort study in South Korea.

BACKGROUND: Low socioeconomic status is a risk factor for chronic obstructive pulmonary disease (COPD); however, the association between low household income and COPD in young populations remains unclear. METHODS: We screened individuals aged 20-39 years who underwent the national health examination between 2009 and 2012 using the Korean National Health Information Database, which was searched until December 2019. We identified 5 965 366 eligible individuals, and 13 296 had newly developed COPD based on health insurance claims. We evaluated household income levels based on the health insurance premiums, categorised them into quartiles and 'Medical aid' (the lowest 3% income group), and assessed the annual income status from the preceding 4 years. Multivariate Cox proportional hazard models were used to estimate the adjusted HR (aHR) of risk factors for COPD. RESULTS: In the Medical aid group, the incidence rate for developing COPD was 0.56/1000 person-years, with an aHR of 2.45 (95% CI 1.91 to 3.13) compared with that of the highest income quartile group. This association was prominent in consecutive recipients of Medical aid (aHR 2.37, 95% CI 1.80 to 3.11) compared with those who had never been Medical aid beneficiaries. Those who experienced a decline in household income between the previous (preceding 4 years) and baseline time points had an increased risk of developing COPD, regardless of previous income status. CONCLUSION: Low household income was associated with an increased risk of developing COPD in the young population. This risk was augmented by sustained low income and declining income status.

Editor's Choice - Glycaemic Status and Risk of Abdominal Aortic Aneurysm: A Nationwide Cohort Study of Four Million Adults using Korean National Health Screening Data.

OBJECTIVE: This retrospective cohort study aimed to confirm the previously reported inverse association between diabetes mellitus (DM) and abdominal aortic aneurysm (AAA) using large population based data. It also investigated the associations between AAA and impaired fasting glucose (IFG) and new onset DM (not yet treated). METHODS: A representative dataset was obtained from the Korean National Health Insurance Service. Participants who were aged ≥ 50 years and received a national health examination in 2009 were included and followed until 31 December 2019. Glycaemic status was defined based on fasting plasma glucose level and the relevant diagnostic codes. AAA was ascertained using medical facility use records with relevant diagnostic codes or aneurysm repair surgery. A Cox proportional hazards model was used to examine the association between glycaemic status and AAA, with adjustment for confounders. Additionally, the interactions between glycaemic status and subgroups based on baseline characteristics were examined. RESULTS: The study population comprised 4 162 640 participants. Participants with IFG or DM were significantly more likely to be male, older, and have comorbidities compared with normoglycaemic participants at baseline. The incidence of AAA was lower in participants with IFG or DM compared with normoglycaemic participants. The AAA risk was lower in patients with DM than in patients with IFG, and decreased linearly according to glycaemic status: the adjusted hazard ratio was 0.88 (95% confidence interval [CI] 0.85 - 0.91) for IFG, 0.72 (95% CI 0.67 - 0.78) for newly diagnosed DM, 0.65 (95% CI 0.61 - 0.69) for DM duration < 5 years, and 0.47 (95% CI 0.44 - 0.51) for DM duration ≥ 5 years compared with the normoglycaemia group. Both IFG and DM were related to reduced AAA risk in all subgroups, suggesting an independent association. CONCLUSION: Both IFG and DM, even when not treated with antihyperglycaemic medication, were associated with a lower incidence of AAA. The AAA risk decreased linearly according to DM duration.

Physical Activity and the incidence of sepsis: A 10-year observational study among 4 million adults.

BACKGROUND: As the group at high risk for sepsis is increasing with the aging of the population, physical activity (PA), which has beneficial effects on various diseases, needs to be considered as a personalized prevention strategy for sepsis without direct anti-sepsis drug. PURPOSE: To examine the association between the amount of PA (based on intensity, duration, and frequency) and the incidence rates of sepsis and mortality after sepsis. METHODS: This was a large-scale, retrospective, longitudinal cohort study using data from the Korean National Health Insurance Service and the biennial general health screening program. The amount of PA self-reported at the time of the health screening was categorized as non-PA, mild (<500 metabolic equivalents [METs]-Min/Week), moderate (500-1000), severe (1000-1500), and extreme (≥1500). The multivariable regression model was adjusted for age, sex, income, body mass index, smoking, alcohol consumption, diabetes, hypertension, dyslipidemia, and chronic diseases. RESULTS: From 4,234,415 individuals who underwent a health screening in 2009, 3,929,165 subjects were selected after exclusion for wash-out period and a 1-year lag period, and then observed for the event of sepsis or all-cause death until December 2020. During a median 10.3 years of follow-up, 83,011 incidents of sepsis were detected. The moderate-PA group showed the lowest incidence (1.56/1000 person-years) and risk for sepsis, with an adjusted hazard ratio (aHR) of 0.73 (95% CI, 0.72-0.75, P < 0.001) compared with the non-PA group. The occurrence of sepsis among people aged ≥65 years and ex-smokers were significantly lower in the moderate-PA group (aHR; 0.77, 95% CI; 0.74-0.79; and 0.68, 0.64-0.71, respectively, Ps < 0.001). The long-term all-cause mortality after sepsis was significantly lower in the PA group than in the non-PA group (overall P = 0.003). CONCLUSIONS: Physical activity is associated with a lower risk of sepsis, especially in elderly people who have the highest incidence of sepsis. The protective effects of aerobic PA on sepsis might need to be incorporated with other interventions in sepsis guidelines through the accumulation of future studies.

Risk of Head and Neck Cancer in Patients with Psoriasis: A Nationwide Population-based Study.

An association between psoriasis and cancer risk has been suggested in prior studies, but few have focused on head and neck cancers. Using the Korean National Health Insurance Service database, the relevance between psoriasis and head and neck cancer risks was investigated in a cross-sectional study of 3,869,264 individuals over 20 years of age, who received general health examination in 2009 and were followed until 2020. Head and neck cancer incidence rates were compared between individuals with and without psoriasis, and contributing factors were analysed. The head and neck cancer risk was significantly increased in the psoriasis group compared with the non-psoriasis group (hazard ratio [HR] 1.36; 95% confidence interval [CI] 1.07-1.74; p = 0.01) after adjusting for age, sex, body mass index, income, smoking, alcohol, exercise, diabetes mellitus, hypertension and dyslipidaemia. The risk was especially elevated for nasopharyngeal (HR 2.04; 95% CI 1.12-3.70; p = 0.02) and salivary gland cancer (HR 1.96; 95% CI 1.08-3.56; p = 0.03). Alcohol consumption significantly influenced the risk, particularly for oropharyngeal and oral cavity cancer. Our study provides insights into the potential risks of head and neck cancer in patients with psoriasis, which could aid in refining patient management strategies.

Gamma-glutamyl transferase and the risk of all-cause and disease-specific mortality in patients with diabetes: A nationwide cohort study.

BACKGROUND: There exists a paucity of data regarding whether gamma-glutamyl transferase is associated with disease-specific mortality in patients with type 2 diabetes mellitus. This study aimed to investigate the association of serum gamma-glutamyl transferase levels with all-cause and disease-specific mortality in patients with diabetes mellitus using a Korean nationwide health-screening database. METHODS: A total of 9 687 066 patients without viral hepatitis or liver cirrhosis who underwent health examination in 2009 were included. These patients were divided into four groups according to sex-specific quartiles of serum gamma-glutamyl transferase levels. RESULTS: During a median follow-up period of 8.1 years, 222 242 deaths were identified. The all-cause mortality rate increased as the serum gamma-glutamyl transferase levels became higher (highest quartile vs lowest quartile: hazard ratio [HR], 1.57; 95% confidence interval [CI], 1.55-1.59; p for trend <.001). Similar trends were observed for cardiovascular disease (HR, 1.57; 95% CI, 1.53-1.62), ischemic heart disease (HR, 1.40; 95% CI, 1.33-1.48), and stroke (HR, 1.72; 95% CI, 1.60-1.85) in the highest quartile, as compared with the lowest quartile (p for trend <.001). As the gamma-glutamyl transferase quartiles became higher, mortality rates related to cancer (HR, 1.56; 95% CI, 1.52-1.60), liver disease (HR, 9.42; 95% CI, 8.81-10.07), respiratory disease (HR, 1.55; 95% CI, 1.49-1.62), and infectious disease (HR, 1.73; 95% CI, 1.59-1.87) also increased in the highest quartile, compared with the lowest quartile (p for trend <.001). CONCLUSIONS: Serum gamma-glutamyl transferase levels may be useful for the risk assessment of all-cause and disease-specific mortality among patients with type 2 diabetes mellitus.

The Relation Between Cigarette Smoking and Development of Sepsis: A 10-Year Follow-Up Study of Four Million Adults from the National Health Screening Program.

BACKGROUND: Sepsis remains a growing global health concern with soaring mortality and no direct anti-sepsis drug. Although smoking has distinct deleterious effects on chronic inflammatory illnesses and can impair immune function, a comprehensive analysis of the connection between sepsis and smoking is lacking. METHODS: This large-scale longitudinal cohort study retrospectively assessed adults aged ≥ 20 years who underwent national health checkups under the Korean National Health Insurance Service between January and December 2009 (N = 4,234,415) and were followed up for 10 years. Sepsis was identified based on the International Classification of Diseases, 10th Revision codes, and smoking status, including accumulated amount, was collected through a self-administered questionnaire. The Cox proportional hazard regression model was used, adjusting for age, sex, household income, body mass index, drinking, exercise, diabetes, hypertension, dyslipidemia, and chronic renal disease. RESULTS: After excluding cases with sepsis occurring before follow-up or after ≤ 1 year of follow-up, 3,881,958 participants, including non-smokers (N = 2,342,841), former smokers (N = 539,850), and active smokers (N = 999,267), were included. Compared to non-smokers, all active smokers (adjust hazard ratio: 1.41, 95% confidence interval 1.38-1.44) and former smokers (1.10, 1.07-1.14) with ≥ 20 pack-years exhibited a significantly higher risk of sepsis (p < 0.001). Smoking of ≥ 30 pack-years in former and active smokers groups significantly increased sepsis incidence (adjust hazard ratio [95% confidence interval] 1.34 [1.31-1.38], p < 0.001). CONCLUSIONS: Smoking is closely associated with the incidence of sepsis. Smoking cessation may help in the primary prevention of sepsis.

Diabetes duration, cholesterol levels, and risk of cardiovascular diseases in individuals with type 2 diabetes.

OBJECTIVE: To investigate the association of diabetes duration with cardiovascular disease (CVD) risk and to examine the relationship between lipid levels and CVD risk over the duration. METHODS: Using the Korean National Health Insurance Service Cohort database, we identified 2,359,243 subjects with type 2 DM aged ≥20 years in 2015-2016. Baseline lipid levels and diabetes duration were evaluated, and followed up until December 2020 (mean follow-up, 3.9 years). Subjects were categorized according to diabetes duration (new-onset, <5 years, 5-9 years, or ≥10 years). We analyzed the new-onset diabetes group with low-density lipoprotein cholesterol (LDL-C), <70 mg/dL, as the reference group. The hazard ratios (HRs) and 95% confidence intervals (CIs) of myocardial infarction (MI), and ischemic stroke (IS) were estimated using a Cox proportional hazards model adjusted for potential confounders. RESULTS: During follow-up, 45,883 cases of MI and 53,538 cases of IS were identified. The risk of MI or IS began to increase at LDL-C ≥160 mg/dL in the new-onset diabetes group, and at LDL-C ≥130 mg/dL in the diabetes duration <5 years group. Among subjects with a diabetes duration of 5-9 years, LDL-C 100-129 mg/dL, LDL-C 130-159 mg/dL, and ≥160 mg/dL were significantly associated with the risk of MI, with HRs (95% CI) of 1.13 (1.04-1.22), 1.28 (1.17-1.39), and 1.58 (1.42-1.76), respectively. The risk of MI in the diabetes duration ≥10 years group was increased by 16%, even in the LDL-C 70-99 mg/dL population (HR [95% CI] 1.16 [1.08-1.25]). CONCLUSIONS: This population-based longitudinal study revealed that the LDL-C cutoff level for increasing the risk of cardiovascular disease varied with diabetes duration, and that the target LDL-C level should depend on the duration.

Risk of Depression according to Cumulative Exposure to a Low-Household Income Status in Individuals with Type 2 Diabetes Mellitus: A Nationwide Population- Based Study.

BACKGRUOUND: We aimed to identify the risk of incident depression according to cumulative exposure to a low-household income status in individuals with type 2 diabetes mellitus (T2DM). METHODS: For this retrospective longitudinal population-based cohort study, we used Korean National Health Insurance Service data from 2002 to 2018. Risk of depression was assessed according to cumulative exposure to low-household income status (defined as Medical Aid registration) during the previous 5 years among adults (aged ≥20 years) with T2DM and without baseline depression who underwent health examinations from 2009 to 2012 (n=2,027,317). RESULTS: During an average 6.23 years of follow-up, 401,175 incident depression cases occurred. Advance in cumulative number of years registered for medical aid during the previous 5 years from baseline was associated with an increased risk of depression in a dose-dependent manner (hazard ratio [HR], 1.44 [95% confidence interval (CI), 1.38 to 1.50]; HR, 1.40 [95% CI, 1.35 to 1.46]; HR, 1.42, [95% CI, 1.37 to 1.48]; HR, 1.46, [95% CI, 1.40 to 1.53]; HR, 1.69, [95% CI, 1.63 to 1.74] in groups with 1 to 5 exposed years, respectively). Insulin users exposed for 5 years to a low-household income state had the highest risk of depression among groups categorized by insulin use and duration of low-household income status. CONCLUSION: Cumulative duration of low-household income status, defined as medical aid registration, was associated with an increased risk of depression in a dose-response manner in individuals with T2DM.

Smoking Behavior Change and the Risk of Heart Failure in Patients With Type 2 Diabetes: Nationwide Retrospective Cohort Study.

BACKGROUND: Heart failure (HF) is one of the most common initial manifestations of cardiovascular disease in patients with type 2 diabetes. Although smoking is an independent risk factor for HF, there is a lack of data for the incidence of HF according to changes in smoking behaviors in patients with type 2 diabetes. OBJECTIVE: We aimed to examine the association between interval changes in smoking behavior and the risk of HF among patients with type 2 diabetes. METHODS: We conducted a retrospective cohort study using the National Health Insurance Service database. We identified 365,352 current smokers with type 2 diabetes who had 2 consecutive health screenings (2009-2012) and followed them until December 31, 2018, for the incident HF. Based on smoking behavior changes between 2 consecutive health screenings, participants were categorized into quitter, reducer I (≥50% reduction) and II (<50% reduction), sustainer (reference group), and increaser groups. RESULTS: During a median follow-up of 5.1 (IQR 4.0-6.1) years, there were 13,879 HF cases (7.8 per 1000 person-years). Compared to sustainers, smoking cessation was associated with lower risks of HF (adjusted hazard ratio [aHR] 0.90, 95% CI0.86-0.95), whereas increasers showed higher risks of HF than sustainers; heavy smokers who increased their level of smoking had a higher risk of HF (aHR 1.13, 95% CI 1.04-1.24). In the case of reducers, the risk of HF was not reduced but rather increased slightly (reducer I: aHR 1.14, 95% CI 1.08-1.21; reducer II: aHR 1.03, 95% CI 0.98-1.09). Consistent results were noted for subgroup analyses including type 2 diabetes severity, age, and sex. CONCLUSIONS: Smoking cessation was associated with a lower risk of HF among patients with type 2 diabetes, while increasing smoking amount was associated with a higher risk for HF than in those sustaining their smoking amount. There was no benefit from reduction in smoking amount.

Cumulative effect of impaired fasting glucose on the risk of dementia in middle-aged and elderly people: a nationwide cohort study.

The relationship between prediabetes and dementia remains controversial. We aimed to examine the association between cumulative exposure to impaired fasting glucose (IFG) and the risk of dementia in the general population. 1,463,066 middle-aged and elderly subjects who had had health examinations for four consecutive years were identified from a Korean nationwide population-based cohort database. IFG was defined as fasting blood glucose 100-125 mg/dL, and the risk of dementia-according to the number of IFG exposure (range 0-4)-was analyzed using the multivariable Cox proportional-hazards model. During the median 6.4 years of follow-up, 7614 cases of all-cause dementia, 5603 cases of Alzheimer's disease, and 1257 cases of vascular dementia occurred. There was a significant trend towards a higher risk of all-cause dementia (P for trend = 0.014) and Alzheimer's disease ( Pfor trend = 0.005) according to the cumulative exposure to IFG, but with a modest (approximately 7-14%) increase in the hazards. A significant stepwise increase in the risk of all-cause dementia and Alzheimer's disease was seen in non-obese subjects, whereas no significant association was observed in obese subjects. This study supports the association between prediabetes and incident dementia and emphasizes that even mild hyperglycemia should not be overlooked.

Metabolic syndrome and the risk of abdominal aortic aneurysm: A nationwide cohort study.

BACKGROUND AND AIMS: The association between metabolic syndrome (MetS) and abdominal aortic aneurysm (AAA) remains unclear. We investigated the potential association between AAA and MetS and its components in a large population-based cohort. METHODS: We used the Korean National Health Insurance Service database including 4,162,640 participants aged ≥50 years who received a routine health examination in 2009. Cox proportional hazards models were used to analyze the association between MetS and its components (elevated waist circumference, blood pressure, glucose, triglycerides, and reduced high-density lipoprotein cholesterol [HDL-C]) with AAA incidence, with adjustment for confounders. RESULTS: During a median 9.4 years of follow-up, 18,160 participants developed incident AAA. MetS was associated with an increased risk of AAA compared to the non-MetS group (adjusted hazard ratio [aHR], 1.38; 95% confidence interval [CI], 1.34-1.43). Among the individual components, elevated waist circumference, blood pressure, triglycerides, and reduced HDL-C were associated with increased AAA risk, while elevated glucose alone was associated with reduced AAA risk (aHR, 0.85; 95% CI, 0.82-0.87). AAA risk also increased linearly with the increasing number of MetS components, with the highest risk found in the presence of all 5 components (aHR, 1.98, 95% CI, 1.83-2.15). CONCLUSIONS: MetS and its individual components, with the exclusion of elevated glucose, were associated with higher risk of AAA. Further studies are warranted to elucidate the association between MetS and AAA.

Smoking behavior change and the risk of pneumonia hospitalization among smokers with diabetes mellitus.

Smoking patients with diabetes mellitus (DM) are at greater risk of developing pneumonia. How smoking behavior changes affect the risk of pneumonia hospitalization, however, remains unclear. Therefore, we investigated the association between smoking behavior change and the risk of pneumonia hospitalization in patients with DM. From January 1, 2009 and December 31, 2018, we investigated the association between smoking behavior change and the risk of pneumonia hospitalization in patients with DM. A total of 332,798 adult patients with DM from the Korean National Health Insurance System database who underwent health screening examination between 2009 and 2012, and were smokers at the first health examination were included. During a mean follow-up of 4.89 years, 14,598 (4.39%) incident pneumonia hospitalization cases were identified. Reducers had a slightly increased risk of pneumonia hospitalization (aHR 1.06, 95% CI 1.01-1.10) compared to sustainers. Quitters did not have a significant association with incidence of pneumonia hospitalization. However, increasers had 13% higher risk of pneumonia hospitalization (aHR 1.13, 95% CI 1.07-1.18), regardless of whether initial smoking was light, moderate, or heavy. Our study showed that an increase in smoking intensity was associated with an increased risk of pneumonia hospitalization in people with DM. However, a protective effect of smoking reduction or cessation on pneumonia risk was not demonstrated.

Effect of smoking on the development of chronic obstructive pulmonary disease in young individuals: a nationwide cohort study.

Background: Cigarette smoking is an important risk factor for developing chronic obstructive pulmonary disease (COPD). However, the effect of smoking on the development of COPD in young individuals remains unclear. We aimed to evaluate the effect of smoking on COPD development in young individuals. Methods: Using the Korean National Health Information Database, we screened individuals aged 20-39 years who participated in the national health check-up between 2009 and 2012. We defined physician-diagnosed COPD based on health insurance claims and searched the database until December 2019. We identified 6,307,576 eligible individuals, and 13,789 had newly developed COPD. We used multivariate Cox proportional hazards models to estimate the adjusted hazard ratio (aHR) of risk factors for COPD. Results: The incidence rate for developing COPD was 0.26/1000 person-year. The risk of developing COPD was significantly higher in current smokers [aHR 1.46, 95% confidence interval (CI) 1.39-1.53] and former smokers (aHR 1.21, 95% CI 1.14-1.29) than in non-smokers. Furthermore, the risk increased with increasing smoking amounts (≥20 pack-years, aHR 2.24; 10-20 pack-years, aHR 1.55; <10 pack-years, aHR 1.27). Female participants had a higher relative risk of developing COPD due to smoking, compared with their male counterparts. Conclusion: Cigarette smoking increased the risk of developing COPD in young individuals. Current and heavy smokers had higher risks of developing COPD than non-smokers. Female smokers were more likely to develop COPD than male smokers.

Diabetes-Related Risk Factors for Exudative Age-Related Macular Degeneration: A Nationwide Cohort Study of a Diabetic Population.

Purpose: The purpose of this study was to identify diabetes-related risk factors for exudative age-related macular degeneration (AMD). Methods: This was a nationwide population-based cohort study using authorized clinical data provided by the Korean National Health Insurance Service. A total of 1,768,018 participants with diabetes over 50 years of age participated in the Korean National Health Screening Program between 2009 and 2012. Data on covariates, including age, sex, income level, systemic comorbidities, behavioral factors, and diabetes-related parameters, including duration of diabetes, use of insulin for diabetes control, number of oral hypoglycemic agents used, and accompanying vision-threatening diabetic retinopathy, were collected from health screening results and claims data. Patients were followed up until December 2018. Incident cases of exudative AMD were identified using registered diagnostic codes from the claims data. The prospective association of diabetes-related parameters with incident exudative AMD was investigated using the multivariable-adjusted Cox proportional hazard model. Results: During an average follow-up period of 5.93 years, 7331 patients were newly diagnosed with exudative AMD. Compared to those who had diabetes for less than 5 years, individuals with diabetes for 5 years or more had a greater risk of future exudative AMD development, with a hazard ratio (95% confidence interval) of 1.13 (1.07-1.18) in the fully adjusted model. Use of insulin for diabetes control and the presence of vision-threatening diabetic retinopathy were also associated with an increased risk of exudative AMD with a hazard ratio (95% confidence interval) of 1.16 (1.07-1.25) and 1.40 (1.23-1.61), respectively. Conclusions: A longer duration of diabetes, administration of insulin for diabetes control, and comorbid vision-threatening diabetic retinopathy were associated with an increased risk of developing exudative AMD.

Smoking behavior change and risk of cardiovascular disease incidence and mortality in patients with type 2 diabetes mellitus.

BACKGROUND: We aimed to examine the association between smoking behavior change and risk of cardiovascular disease (CVD) incidence and mortality in patients with type 2 diabetes mellitus (T2DM). METHODS: This study used nationwide data from the Korean National Health Insurance System and included 349,137 T2DM patients who smoked. Smoking behavior changes were defined with five groups: quitters, reducers I (≥ 50% reduction), reducers II (20-50% reduction), sustainers (± 20%), and increasers (≥ 20% increase) from the number of cigarettes/day at the baseline. RESULTS: During a median follow-up of 5.1 years, 6,514 cases of myocardial infarction (MI) (1.9%), 7,837 cases of ischemic stroke (IS) (2.2%), and 14,932 deaths (4.3%) were identified. Quitters had a significantly decreased risk of MI (adjusted hazard ratio [aHR] 0.80, 95% CI 0.75-0.86) and IS (aHR 0.80, 95% CI 0.75-0.85) compared to sustainers, whereas reducers did not have a significant association with the risk of MI (aHR 1.03, 95% CI 0.94-1.13) and IS (aHR 1.00, 95% CI 0.92-1.08) in reducer I. Quitters also had a lower all-cause and CVD mortality than sustainers. CONCLUSIONS: Smoking cessation was associated with decreased CVD incidence, and all-cause and CVD mortality among T2DM patients. However, smoking reduction was not associated with decreased risks for these.