Diabetes burden and prevention in Korea and the Western Pacific Region

Trends in Frailty Prevalence Among Older Adults in Korea: A Nationwide Study From 2008 to 2020

BACKGROUND

We aimed to evaluate the nationwide trend of the prevalence of frailty in older adults in Korea from 2008 to 2020 to inform future geriatric healthcare policies.

METHODS

The study used data of individuals aged 65 years and older from the Korea National Health and Nutrition Examination Survey, a nationwide repeated cross-sectional survey. Frailty was defined using frailty index, classified as non-frail (frailty index ≤ 0.15), pre-frail (0.15 < frailty index ≤ 0.25), or frail (frailty index > 0.25).

RESULTS

The study included 17,784 individuals, with the mean age of 72.4 and mean frailty index of 0.2. The prevalence of frailty in older adults in South Korea decreased significantly from 2008 (41.1%) to 2020 (23.1%). The decrease in the frailty index was observed in all age groups (all P < 0.05). As components of frailty index, we found that certain comorbidities, such as dyslipidemia, diabetes mellitus, and cardiovascular disease, have increased over time, while factors such as chewing difficulty, activity limitation, and smoking, have decreased.

CONCLUSION

The prevalence of frailty in older adults in South Korea has decreased significantly during the study period. Historical improvements in healthcare access and preventive measures may have contributed to this trend.

Effect of dipeptidyl peptidase IV inhibitors, thiazolidinedione, and sulfonylurea on osteoporosis in patients with type 2 diabetes: population-based cohort study

The population-based cohort study used the Korean National Health Insurance claims database to evaluate the effect of anti-diabetic drugs on osteoporosis. The use of DPP-IV inhibitors does not increase the risk of osteoporosis compared with the use of sulfonylureas in patients with type 2 diabetes mellitus, while a weak association was found between thiazolidinediones and increased risk of osteoporosis.

PURPOSE

The current study aimed to evaluate the effect of dipeptidyl peptidase IV inhibitors (DPP-IVi), thiazolidinedione (TZD), and sulfonylurea (SU) on osteoporosis in patients with type 2 diabetes.

METHODS

A population-based cohort study was conducted in the Republic of Korea using the Korean National Health Insurance claims database. Data from 2012 to 2017 for patients of 50-99 years of age who were prescribed DPP-IVi, TZD, or SU during 2013-2015 were extracted from the database. Based on pre-defined criteria, a total of 381,404 patients were analyzed after inverse probability of treatment weighting. The association between the study drugs and osteoporosis was estimated using Cox proportional hazards models. Data of 220,166 patients who were prescribed DPP-IVi, 18,630 who were prescribed TZD, and 142,608 patients who were prescribed SU were set.

RESULTS

In the multivariate-adjusted analysis, the hazard ratio (HR) of osteoporosis in the DPP-IVi group was not significantly different from that of the SU group (HR: 0.97; 95% confidence interval (CI) 0.94-1.00), whereas the HR of osteoporosis in the TZD group was higher (HR: 1.13; 95% CI 1.06-1.20). In the subgroup analysis, the HRs of osteoporosis were higher with pioglitazone (HR: 1.14; 95% CI 1.06-1.23) in the TZD group and with glibenclamides (HR: 1.39; 95% CI 1.09-1.77) in the SU group, whereas drugs with lower HR in the DPP-IVi group were saxagliptin (HR: 0.93; 95% CI 0.87-0.99) and sitagliptin (HR: 0.93; 95% CI 0.89-0.97).

CONCLUSION

DPP-IV inhibitors do not increase the risk of osteoporosis compared with sulfonylureas in patients with type 2 diabetes mellitus, while a weak association was found between thiazolidinediones and increased risk of osteoporosis.

Gender Differences in the Relationship between Type 2 Diabetes Mellitus and Employment: Evidence from the Korea Health Panel Study

Previous studies have analyzed the impact of diabetes mellitus on labor market participation by men and women, but gender difference between type 2 diabetes mellitus (T2DM) and employment has not been the focus. This study aims to explore gender differences between T2DM and employment status. Data from the Korea Health Panel Study, 2013-2015 were analyzed by distinguishingT2DM and non-diabetes (N = 11,216). The empirical model was established and the generalized two-stage least squares (2SLS) was estimated, controlling for endogeneity. A family history of diabetes, as an instrumental variable, was related to an individual's genetic predisposition to develop diabetes. The estimated results for the 2SLS showed the interaction effects between T2DM and employment. T2DM had a statistically significant and negative effect on employment for women only. The comparison with non-diabetes showed that women with T2DM had a lower probability of employment by 51.9% (p < 0.05). Exposing gender bias in employment suggests that healthcare policies and disease management programs for diabetic patients should adopt gender-specific remedies.

Differential Effects of Typical Korean Versus American-Style Diets on Gut Microbial Composition and Metabolic Profile in Healthy Overweight Koreans: A Randomized Crossover Trial

The Westernized diet has been associated with the pathogenesis of metabolic diseases, whereas a Korean diet has been reported to exert beneficial effects on health in several studies. However, the effects of Western and Korean diets on the gut microbiome and host metabolome are unclear. To examine the diet-specific effects on microbiome and metabolome, we conducted a randomized crossover clinical trial of typical Korean diet (TKD), typical American diet (TAD), and recommended American diet (RAD). The trial involved a 4-week consumption of an experimental diet followed by a 2-week interval before diet crossover. 16S rRNA sequencing analysis identified 16, 10, and 14 differential bacteria genera specific to TKD, RAD, and TAD, respectively. The Firmucutes-Bacteroidetes ratio was increased by TKD. Nuclear magnetic resonance metabolome profiling revealed that TKD enriched branched chain amino acid metabolism, whereas ketone body metabolism was evident in RAD and TAD. Microbiome and metabolome responses to the experimental diets varied with individual enterotypes. These findings provide evidence that the gut microbiome and host metabolome rapidly respond to different cultural diets. The findings will inform clarification of the diet-related communication networks of the gut microbiome and host metabolome in humans.

Identification of Dietary Patterns Associated with Incidence of Hyperglycemia in Middle-Aged and Older Korean Adults

Little is known about the association between dietary patterns and hyperglycemia incidence among Korean adults. Hence, we aimed to prospectively investigate the major dietary patterns associated with hyperglycemia among middle-aged and older Korean adults. In total, 55,457 adults (18,292 men and 37,165 women) aged 40 to 79 years, who were previously enrolled in the Health Examinee Study of the Korean Genome and Epidemiology Study and had no history of type 2 diabetes mellitus (T2DM) or cancer at baseline, were included. Dietary patterns were identified by a factor analysis based on dietary data, which were assessed at baseline using a validated food-frequency questionnaire. Participants were classified as having hyperglycemia if fasting blood glucose levels were ≥126 mg/dL or physician diagnosed T2DM during follow-up. Multivariable Cox proportional hazard models were used to examine the associations between each dietary pattern and future hyperglycemia risk after adjusting for potential confounders. After a mean follow-up of 4.9 years, 2574 new cases of hyperglycemia were identified. Using a factor analysis, four distinct dietary patterns were identified: “prudent;” “fatty fish, meat, and flour-based food;” “coffee and sweets;” and “whole grain (men)” or “white rice (women).” The “prudent” pattern was inversely associated with hyperglycemia risk only in women (hazard ratio [HR], 0.75; 95% confidence interval [CI], 0.63–0.89; p for trend = 0.0003). Conversely, women in the highest quintile of the “fatty fish, meat, and flour-based food” pattern showed an increased risk of hyperglycemia (HR, 1.22; 95% CI, 1.03–1.44; p for trend = 0.0210) compared with those in the lowest quintile. The “coffee and sweets” and “white rice” patterns were not associated with hyperglycemia risk in women. The dietary patterns observed in men had no associations with hyperglycemia incidence. Our findings suggest that a diet rich in vegetables, mushrooms, seaweeds, fruits, and soy products and low in fatty fish and high-fat meat may potentially play a protective role in T2DM development with sex differences in middle-aged and older Korean adults.

Why health policies should be transnational: A case for East Asia Pacific countries

This paper argues that health policies should transcend national boundaries yet should not reach the supranational level. Along with multinational global health efforts, such cross-national health policies are essential to leverage joint efforts by countries learning from their peers that experience similar health system challenges. In our analysis, we used World Bank Health, Nutrition, and Population (HNP) data from 1995 to 2014 for East Asia Pacific (EAP) countries to explore health system comparability across member nations. We applied a hierarchical cluster analysis using Ward's method and a squared Euclidean distance approach to classify 24 EAP countries into four relatively stable clusters based on their (dis)similarities over nine selected health expenditure and health system performance related indicators. One-way analysis of variance (ANOVA) was used to assess the discreteness of the formed clusters. Each cluster had unique characteristics based on the included indicators and health system performance of the member countries. We present transnational health policy recommendations for the EAP region based on both our use of robust methodology and the resulting comparative clusters.

Trends in the prevalence and management of diabetes in Korea: 2007-2017

OBJECTIVES

This study analyzed Korea National Health and Nutrition Examination Survey data from 2007 to 2017 to assess trends in the prevalence, treatment, and control of diabetes in Korean adults ≥30 years of age.

METHODS

Prevalent diabetes was defined as a fasting plasma glucose level ≥126 mg/dL, self-reported use of anti-diabetic treatment (insulin or oral anti-diabetic drugs), or diabetes diagnosis by a physician. Target levels were defined as glycosylated hemoglobin <6.5% or <7.0%, blood pressure <130/80 mmHg, and total cholesterol <200 mg/dL. All survey waves were age-standardized to the 2005 Korean census population.

RESULTS

Diabetes prevalence increased from 9.6% in 2007-2009 to 10.8% in 2016-2017 (p<0.001). Impaired fasting glucose prevalence significantly increased in both genders and almost every age group. Diabetes awareness and glycemic control did not show an increasing trend; however, the treatment rate and proportion of people diagnosed with diabetes achieving target blood pressure and total cholesterol levels improved from 57.2% to 63.5% (p=0.008), from 41.1% to 53.2% (p<0.001), and from 65.0% to 78.0% (p<0.001), respectively.

CONCLUSIONS

From 2007 to 2017, the prevalence of diabetes increased moderately in Korea, whereas the diabetes treatment rate and the proportion of people diagnosed with diabetes achieving target blood pressure and total cholesterol levels improved. However, awareness of diabetes and glycemic control require significant improvements. A national-level action plan is required to raise awareness about diabetes and prediabetes, with the goal of improving glycemic control and minimizing the occurrence of adverse health outcomes.

Association of C-Reactive Protein with Risk of Developing Type 2 Diabetes Mellitus, and Role of Obesity and Hypertension: A Large Population-Based Korean Cohort Study

This study was undertaken to assess the associations of C-reactive protein (CRP) with incident type-2 diabetes mellitus (T2DM) and to determine the joint effect of obesity and hypertension on them in the large-scale population-based Korean cohort of the Korean Genome and Epidemiology study (KoGES). We included 22,946 men and women from 11 rural communities at baseline (2005–2011). Epidemiological data and blood samples were collected. Incident physician-diagnosed T2DM cases (130 men and 148 women) were self-reported or based on fasting glucose ≥126 mg/dL or HbA1c level ≥6.5% during a median follow-up of 3.0 years (58,916 person-years) between 2007 and 2014. After multivariate adjustment for T2DM risk factors, the hazard ratios for developing T2DM in the highest CRP tertile (T3), compared with the lowest (T1), was 2.80 (1.73–4.52; p for trend <0.0001) in women and 1.67 (1.00–2.45; p for trend 0.02) in men. The associations between CRP and incident T2DM were more prominent among the older group (≥50 years). And CRP and its combination with obesity and hypertension were associated with increased risk of T2DM. In conclusion, we found positive associations between CRP and incident T2DM in a large population-based Korean cohort.

Evaluating the prevalence, awareness, and control of hypertension, diabetes, and dyslipidemia in Korea using the NHIS-NSC database: A cross-sectional analysis

This study aimed to evaluate the prevalence, awareness, and control of hypertension, diabetes, and dyslipidemia in Korea according to sex and age, and to identify factors that were associated with the prevalence, awareness, and control of these cardiovascular risk factors among middle-aged Koreans.A cross-sectional analysis was conducted using 2013 data from the National Health Insurance Service-National Sample Cohort (NHIS-NSC) database. A total of 136,755 individuals were considered eligible based on no history of stroke or heart disease, age of 40 to 64 years at the examination, and completion of health examinations. Data regarding demographic factors and cardiovascular risk factors had been obtained using questionnaires, physical examinations, and blood tests.Hypertension was the most prevalent condition among middle-aged Koreans (25.76%), followed by dyslipidemia (16.58%) and diabetes (10.22%). Among these three conditions, dyslipidemia was associated with the lowest awareness rates (24.14%). Hypertension and diabetes were more prevalent among men than among women, although the prevalence of dyslipidemia was higher among women > 50 years old. The prevalence of hypertension and diabetes increased with advancing age among men and women, although the prevalence of dyslipidemia decreased with age among men (highest prevalence: 50.59% among men aged between 40 and 44 years). Among Korean men (relative to women), the odds ratios were 1.50 for hypertension, 1.96 for diabetes, and 0.82 for dyslipidemia. Age, central obesity, and body mass index were significantly associated with the development of all 3 conditions.There are sex- and age-specific patterns in the prevalence, awareness, and control of hypertension, diabetes, and dyslipidemia in Korea. Dyslipidemia is becoming increasingly common although most middle-aged Koreans are not aware of this condition leading to low control rate. These results may help identify population subgroups at a high risk of hypertension, diabetes, and dyslipidemia, and may guide the management of cardiovascular disease in Korea.

Clinical implication of fasting glucose and systolic/diastolic blood pressure on the prevalence of periodontitis in non-diabetic and non-hypertensive adults using nationally representative data

The prevalence of diabetes mellitus and hypertension is increasing worldwide and an association between fasting glucose/blood pressure and periodontitis has been suggested. The present study was performed to assess the association between fasting glucose and systolic/diastolic blood pressure on the prevalence of periodontitis in non-diabetic and non-hypertensive adults using nationally representative data. Subgroup analysis was performed to evaluate the combined effects of obesity/abdominal obesity and impaired fasting glucose. This study involved a cross-sectional analysis using data from the Republic of Korean National Health and Nutrition Examination Survey from 2013 to 2015. A total of 8,341 respondents without diabetes and hypertension over 19 years old without missing values were included in the present study. A significant increase was observed in the prevalence of periodontitis with increasing systolic blood pressure and diastolic blood pressure. The percentage of periodontitis increased with increased glucose levels, with similar trends in glycated hemoglobin. The odds ratios (ORs) and 95% confidence intervals (CIs) for systolic blood pressure of 90≤x<100, 100≤x<110, 110≤x<120, 120≤x<130 and 130≤x<140 were 1.116 (0.591-2.107), 1.165 (0.624-2.175), 1.238 (0.673-2.278), 1.008 (0.538-1.888) and 1.042 (0.545-1.993), respectively, when systolic blood pressure <90 was considered as a reference. The ORs and 95% CIs for glucose of 90≤x<100, 100≤x<110 and 110≤x<126 were 1.074 (0.92-1.253), 1.214 (0.986-1.494) and 1.358 (1.005-1.834), respectively when glucose <90 was considered as a reference. The association between fasting glucose/blood pressure and periodontitis was confirmed by multiple logistic regression analyses after adjusting for confounding factors among non-diabetic and non-hypertensive Republic of Korean adults. Subgroup analysis revealed that higher ORs of periodontitis were observed in participants with impaired glucose level and obesity when compared with individuals without impaired glucose level or obesity. The results of the present study suggest that detection of fasting glucose and blood pressure may serve as a risk indicator for periodontal disease.

Global region of birth is an independent risk factor for type 2 diabetes in Stockholm, Sweden

Background

In Stockholm, type 2 diabetes (T2D) is a public health concern and much more prevalent in areas with a high proportion of foreign-born individuals. One in five individuals in Stockholm County are born outside of Sweden, and we therefore investigated if global region of birth was associated with diabetes risk, adjusting for established risk factors. Cross-sectional data from the population-based Stockholm Public Health Survey 2010 ( N = 69 115) was combined with registry-based information on country of birth grouped into eight global geographical regions. Cases of T2D were identified through self-reported physician-diagnosed diabetes and age at diagnosis. Region of birth was the independent risk factor and multivariable logistic regression analysis was performed adjusting for the risk factors age, sex, weight status, educational level, multiple dietary factors, tobacco, alcohol and physical activity. T2D prevalence was 5.1% in the sample. Relative to Swedish-born participants, higher odds ratio (OR) were found in those born in Asia [OR 3.2, 95% confidence interval (CI) 2.2-4.7], Sub-Saharan Africa (OR 2.5, 95% CI 1.5-4.1) and North Africa/the Middle East (OR 2.1, 95% CI 1.6-2.8), after adjustment for established risk factors. Participants from Eastern Europe and Latin America had an elevated risk but this did not remain after adjustment for other risk factors. Region of birth was found to be an independent risk factor for T2D for participants born in Asia, Africa and the Middle East. This increased risk should be taken into consideration when allocating resources for prevention, detection and care.

Trends in the pervasiveness of type 2 diabetes, impaired fasting glucose and co-morbidities during an 8-year-follow-up of nationwide Korean population

The prevalence and incidence of type 2 diabetes, impaired fasting glucose, and co-morbidities from 2006 to 2013 in the population aged ≥30 years were estimated using the Korean NHIS database. The prevalence of type 2 diabetes increased 0.2–0.5% annually, from 5.6% in 2006 to 8% in 2013. The prevalence of type 2 diabetes was higher in men than in women and increased with age. The incidence of type 2 diabetes was 0.81% in 2013 and was 1.4 times higher in men than in women and increased with age. An overall decrease in the incidence rate occurred from 2006 to 2013(from 0.95 to 0.81%), which was mirrored in all age groups except the 30–39-year-old group. The prevalence of IFG was 25% in 2013. The prevalence of hypertension(62.5 vs 16.9%) and dyslipidemia(49.5 vs 9.7%) were more prevalent in patients with type 2 diabetes compared to non-diabetic cases. This study shows that type 2 diabetes is both common and increasing and that one-quarter of the Korean adult population has IFG. We also confirmed that the prevalence of hypertension and dyslipidemia are 3.7-fold and 5.1-fold higher, respectively, in diabetic patients than in non-diabetic adults.

Incidence and predictors of type 2 diabetes among Koreans: A 12-year follow up of the Korean Genome and Epidemiology Study

AIM

Because the incidence of type 2 diabetes in Korea has not been clearly defined, we examined the incidence of this condition and its association with impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and other risk factors in a 12-year follow-up Korean community-based prospective cohort study.

METHODS

We recruited 7542 subjects aged 40-69years without diabetes at baseline examination from the Korean Genome and Epidemiology Study and followed these subjects for 12years biennially. Diabetes was defined according to the 2010 American Diabetes Association criteria. The incidence of type 2 diabetes and the predictors of progression to diabetes were analyzed according to baseline glucose tolerance.

RESULTS

The overall incidence of type 2 diabetes was 22.1 per 1000person-years. Subjects with combined IFG-IGT at baseline had the highest incidence of diabetes, which was more than two-fold that of individuals with isolated IFG or isolated IGT (114.4 vs. 51.3 vs. 53.1 per 1000person-years). A multivariate Cox proportional hazards model analysis showed that combined IFG-IGT, which were strong predictors of diabetes, as well as age, urban residence, family history of diabetes, smoking status, abdominal obesity, hypertension, high triglycerides and low HDL cholesterols were also independently associated with progression to diabetes.

CONCLUSIONS

The incidence of type 2 diabetes is relatively high in our Korean community-based sample. Combined IFG-IGT are strong predictors of type 2 diabetes. Measurement of 2-hour plasma glucose in addition to fasting plasma glucose is necessary for the detection of individuals at high risk for development of diabetes.

Factors Associated with Participation in Diabetes Education: The Korea National Health and Nutrition Examination Survey 2007 to 2009

BACKGROUND

A recent study revealed that the participation rate in diabetes education among diabetic patients was only about 50% in Korea. We investigated the factors associated with participation in diabetes education.

METHODS

The study included 1,255 patients (≥19 years old) diagnosed with diabetes drawn from the total Korea National Health and Nutrition Examination Survey 2007 to 2009 population comprising 30,705 individuals. We compared age, sex, and age- and sex-adjusted clinical characteristics in patients who had received diabetes education versus those who had not.

RESULTS

Of the 1,255 patients, 19.8% (n=248) had received diabetes education. Patients in the group who received diabetes education were younger, diagnosed at an earlier age, had a longer diabetes duration and were more likely to be using insulin therapy compared with the group who did not receive diabetes education (P<0.001). The group who received diabetes education included fewer manual workers (P<0.001) but more college graduates (P=0.004) compared with the group who did not receive diabetes education. Logistic regression analysis revealed that longer diabetes duration increased the likelihood of receiving diabetes education (odds ratio [OR], 1.04; 95% confidence interval [CI], 1.01 to 1.06; P=0.004). Junior high school (OR, 0.47; 95% CI, 0.24 to 0.91; P=0.026) and elementary school education levels (OR, 0.34; 95% CI, 0.17 to 0.65; P=0.001) versus college graduation were inversely correlated with participation in diabetes self-management education. Non-insulin therapy reduced the likelihood of receiving diabetes education (OR, 0.37; 95% CI, 0.21 to 0.64; P<0.001).

CONCLUSION

Longer diabetes duration, insulin therapy, and higher education level were positively associated with the completion of diabetes education.

The Diabetes Epidemic in Korea

Diabetes is one of the foremost public health issues worldwide that can lead to complications in many organ systems, and has become a significant cause of morbidity and mortality in Korea. According to data from the National Health Insurance Service (NHIS), about 2.7 million Koreans (8.0%) aged 30 years or older had type 2 diabetes mellitus (T2DM) in 2013. The prevalence of T2DM increased with age and rose from 5.6% in 2006 to 8.0% in 2013. Using data based on The Health Screening Service of the NHIS, 25% of Korean adults were reported to have prediabetes in 2013. The prevalence of an impaired fasting glucose tended to increase over time from 21.5% in 2006 to 25.0% in 2013. Even though nationwide health screening has been regularly conducted as a public service, the proportion of undiagnosed cases of diabetes was still reported to be on the higher side in the latest study. Based on the results of these epidemic studies, further actions will be needed to effectively implement lifestyle changes on a social level and increase measures for the early detection of diabetes to stem the tide of the epidemic.

Trends in Diabetes Incidence in the Last Decade Based on Korean National Health Insurance Claims Data

BACKGROUND

Epidemiological data is useful to estimate the necessary manpower and resources used for disease control and prevention of prevalent chronic diseases. We aimed to evaluate the incidence of diabetes and identify its trends based on the claims data from the National Health Insurance Service database over the last decade.

METHODS

We extracted claims data on diabetes as the principal and first additional diagnoses of National Health Insurance from January 2003 to December 2012. We investigated the number of newly claimed subjects with diabetes codes, the number of claims and the demographic characteristics of this population.

RESULTS

Total numbers of claimed cases and populations with diabetes continuously increased from 1,377,319 in 2003 to 2,571,067 by 2012. However, the annual number of newly claimed diabetic subjects decreased in the last decade. The total number of new claim patients with diabetes codes decreased as 30.9% over 2005 to 2009. Since 2009, the incidence of new diabetes claim patients has not experienced significant change. The 9-year average incidence rate was 0.98% and 1.01% in men and women, respectively. The data showed an increasing proportion of new diabetic subjects of younger age (<60 years) combined with a sharply decreasing proportion of subjects of older age (≥60 years).

CONCLUSION

There were increasing numbers of newly claimed subjects with diabetes codes of younger age over the last 10 years. This increasing number of diabetic patients will require management throughout their life courses because Korea is rapidly becoming an aging society.