We appreciate the comments on our study "The Relationship between Lung Function and Metabolic Syndrome in Obese and Non-Obese Korean Adult Males," which was published in Korean Diabetes J 2010;34:253-260. We reported that insulin resistance, and other metabolic risk factors appear to be related to forced vital capacity (FVC), irrespective of obesity in Korean males. The age, height, and disease were the major determinants of ventilatory function [1]. In our study, there was a significant difference of age between metabolic syndrome (MetS) and non-MetS. So, we studied the relationship between MetS and FVC after adjusting for age. After adjusting age, there was still a significant difference in FVC between MetS and non-MetS groups (93.1 ± 12.1 vs. 97.0 ± 11.5, P < 0.05). Furthermore, insulin resistance and other metabolic components such as waist circumference were independently associated with FVC in a multi-linear regression analysis after adjusting for age and height, the major determinants of ventilatory function, and this was consistent with previous studies [2-5]. It has been reported that lung function is affected by several factors such as body composition and fat distribution, physical activity level, handgrip strength and respiratory muscle power [6-9]. Our study was performed on a limited cross-section of the population, so we could not control the potential biases due to differences in physical activity or respiratory muscle power. However, several studies have reported that insulin resistance is independently associated with lung function [3,10]. These studies reported that the lung function is still inversely associated with insulin resistance after adjusting for compounding factors such as age, height, smoking, and physical activity. Furthermore, Lazarus et al. [11,12] reported that skeletal muscle weakness served as a marker for future risk of insulin resistance, and that impaired lung function can aid in the prediction of development of insulin resistance. They suggested that some metabolic change that eventually leads to insulin resistance may initially induce diminished muscle strength and diminished ventilatory function [12]. So diminished muscle strength may be not confounding factor, but an early marker of insulin resistance. Several reports have suggested that impaired lung function is associated with glucose intolerance, hypertension, and cardiovascular disease, and that lung function is a reliable long-term predictor of mortality in the general population. We suggested that decreased FVC is associated with increased metabolic risk and insulin resistance in Korean males. Further prospective study to elucidate the relationship between lung function and metabolic risk is needed.
Corresponding author: Bon Jeong Ku Department of Internal Medicine, Chungnam National University School of Medicine, 33 Munhwa-ro, Jung-gu, Daejeon 301-721, Korea E-mail: bonjeong@cnu.ac.kr Thank you for your interest in this study, the results of which showed that there is no substantial difference in bone mineral density (BMD) T-score measured using a quantitative ultrasound (QUS) between control and prediabetic men between 40 and 70 years of age [1]. The calcaneal QUS is an evaluation tool used to detect osteoporosis and risk of fractures based on measurements of the foot. It is very useful for clinical application due to its low-cost and high-mobility [2]. Generally, broadband ultrasound attenuation (BUA) and the speed of sound (SOS) are measured and used to calculate BMD. However, in this study, there was a limitation for that data which cannot be presented through a loss of data for BUA and SOS results. Dual-energy X-ray absorptiometry (DXA) has been used as a method to measure BMD [3]. However, due to radiation exposure or mobility restrictions, different examination methods are used to evaluate BMD and risk of fractures depending on the situation. In the case of epidemiologic studies like this one, QUS is used to determine BMD. There have been many reports that the t-scores derived from QUS measurements are correlated with the t-scores derived from DXA measurements [4-6]. In addition, the results of QUS measurements have been expressed as BMD in several studies [4,7,8]. Although DXA is the golden standard for measuring BMD, 100% accuracy in reflecting the real physiological state has not been achieved. Although ‘t-score assessed by QUS’ is a more accurate representation of our measurement than is BMD, we can use BMD as broader meaning when considering the correlation between QUS and DXA. It is a well known fact that insulin has an anabolic effect on bone cells [9,10]. As noted in your comment, the correlation between insulin and BMD showed confusing results in this study [1]. As indicated, statistical limitations or non-linear relationships are likely to be seen. The BMD in type 2 diabetes patients have reported conflicting results according to the study subjects or age groups [11-13]. Because we targeted the aforementioned prediabetic patient group, the BMD in diabetes patients could be projected through this study; however, there was no observed significant difference between prediabetic subjects and the control group. The participants in this study were males between 40 and 70 years of age. Many factors that have an effect on BMD were not considered in this study; therefore, we believe that a prospective control study is required to overcome this limitation. This study is the first to analyze BMD in Korean prediabetic patients, and the results are expected to be clinically useful. We would like to thank you once again for your comments and interest in this study.
BACKGROUND:This study was conducted to evaluate the factors affecting medication adherence in geriatric diabetic patients treated at private clinics and tertiary hospitals. We compared the factors affecting medication adherence between these two patient groups.METHODS:We included 108 diabetic patients older than 65 years treated at one tertiary hospital and 157 patients older than 65 years treated at two private clinics. We conducted an interview survey based on the Health Belief Model, and used a questionnaire that included the self-efficacy variable. For the medication adherence, Morisky's self-report was used.RESULTS:The medication adherence based on Morisky's self-report was significantly higher in tertiary hospital patients (61.1%) compared to private clinic patients (43.2%) (P < 0.01). The results showed that drug storage and self-efficacy were factors affecting adherence to medication in tertiary hospital patients (P < 0.05). The adherence was high in cases of proper drug storage (odds ratio [OR], 5.401) and in cases with high self-efficacy (OR, 13.114). In private clinic patients, financial level (P < 0.05), recognition of the seriousness of diabetes complications (P < 0.05) and self-efficacy (P < 0.01) were associated with medication adherence. The medication adherence was significantly lower in patients whose financial state were moderate than those with lower (OR, 0.410), and medication adherence was significantly higher in patients who had higher perceived severity (OR, 2.936) and in patients with higher self-efficacy (OR, 4.040).CONCLUSION:Different strategies should be used to increase medication adherence in geriatric diabetic patients, depending on institutions whether they are treated.
Reduction of beta cell function and a beta cell mass is observed in both type 1 and type 2 diabetes. Therefore, restoration of this deficiency might be a therapeutic option for treatment of diabetes. Islet transplantation has benefits, such as reduced incidence of hypoglycemia and achievement of insulin independence. However, the major drawback is an insufficient supply of islet donors. Transplantation of cells differentiated in vitro or in vivo regeneration of insulin-producing cells are possible approaches for beta cell/islet regenerative therapy. Embryonic and adult stem cells, pancreatic ductal progenitor cells, acinar cells, and other endocrine cells have been shown to differentiate into pancreatic beta cells. Formation of fully functional beta cells and the safety of these cells are critical issues for successful clinical application.
BACKGROUND:Our aim was to assess the validity of a semi-quantitative food frequency questionnaire (FFQ) by comparison with the 3-day diet record (DR) in patients with type 2 diabetes.METHODS:Eighty five type 2 diabetic patients (aged 33 to 70 years) from the Korean National Diabetes Program (KNDP) completed 3-day DR and FFQ. The FFQ was designed to reflect the eating pattern of Korean type 2 diabetic patients, and was based on the 2003 Korean National Health and Nutrition Examination Survey. The FFQ consists of 85 food items and 12 food groups. The validity of FFQ was assessed by comparison with the 3-day DR.RESULTS:The mean age was 49 +/- 10 years. Clinical characteristic including body weight, diabetic duration, and HbA1c were not different from the total cohort subjects (n = 1,478). There were no significant differences in the mean intake of protein, fat and calcium estimated by the FFQ and the 3-day DR. Energy and carbohydrate estimated by the FFQ were higher than those estimated by the 3-day DR. The correlation coefficient was highest for energy (r = 0.740; P < 0.00) and lowest for iron (r = 0.269; P < 0.05). The Kappa values for energy, carbohydrate, protein, fat and calcium were 0.54, 0.37, 0.36, 0.46, and 0.19, respectively.CONCLUSION:The FFQ is a reasonable instrument for assessing the intake of most macronutrients in Korean type 2 diabetes, although careful consideration is required for the food groups and nutrients for which the FFQ had low validity.
A conference was convened by the Korean Diabetes Association and the Korean Endocrine Society on September 7, 2009 to discuss and organize the results of research on intensive glucose control for the prevention of cardiovascular disease in patients with type 2 diabetes. Professor Kyung Soo Park led the conference, and Professors Kwang Won Kim and Ho Young Son acted as chairmen. Professors Doo Man Kim, Tae Sun Park, and Bong Soo Cha reported on intensive glucose control and diabetic complications, including the UK Prospective Diabetes Study (UKPDS), Diabetes Control and Complication Trial (DCCT) research results, the recently published Action to Control Cardiovascular Risk in Diabetes (ACCORD), Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE), and Veterans Affairs Diabetes Trial (VADT) research, as well as meta-analyses. Professor Jeong-Taek Woo reported on the manuscript written by the committee for the Korean Diabetes Association which dealt with the treatment of diabetes mellitus. Professors Kyung Soo Ko, Joong Yeol Park, Hyun Shik Son, Moon-Kyu Lee, Dong-Won Byun, and Yoon-Sok Chung participated in the discussion and collected information for the manuscript from all of the participants. The aim of the debate was to determine how to establish target goals for intensive glucose control and how to individualize those goals. The participants concluded that there was no need to modify the recommendation of maintaining an HbA1c under 6.5%, the current blood glucose treatment goal that is recommended by the Korean Diabetes Association. In addition, individual target goals for glucose control were recommended depending on the situation of each patient. We report on the consensus statement from the meeting.
To the Editor: We read with interest the study by Noh et al., which demonstrated that the duration of diabetes could be a marker for left ventricular (LV) diastolic dysfunction, independent of other diastolic dysfunction-related variables in type 2 diabetic patients without hypertension or ischemic heart disease [1]. Diabetic cardiomyopathy is diabetes-associated changes in the structure and function of the myocardium that are not directly attributable to other confounding factors, such as coronary artery disease. It is characterized by a latent subclinical period, during which there is evidence of diastolic dysfunction and left ventricular hypertrophy before overt clinical deterioration and systolic failure ensue [2]. Noh’s study demonstrated that diabetes duration is an independent risk factor of LV diastolic dysfunction in a Korean population with type 2 diabetes. Noh’s study included type 2 diabetic patients with normal ECG and without history of ischemic heart disease. However, many diabetic patients have asymptomatic coronary heart disease. Thus, screening patients with only past medical history and normal resting ECG could limit the value of excluding patients with ischemic heart disease. Incorporating exercise testing into patient selection could provide more ideal study subjects [3]. Previous studies reported that LV diastolic dysfunction in diabetic patients is also associated with hyperglycemia, duration of diabetes, insulin resistance, and obesity [2,4]. Noh’s study showed that higher body mass index and longer duration of diabetes were associated with LV diastolic dysfunction in patients with type 2 diabetes. These findings were consistent with the previous reports. Diastolic dysfunction is believed to be the earliest functional change in diabetic cardiomyopathy and is closely correlated with glycated haemoglobin [4]. Hyperglycaemic patients demonstrate an 8% increase in the risk of developing heart failure with every 1% elevation of glycosylated hemoglobin [4]. However, in authors’ study, there was no significant difference in the level of HbA1c between the two groups. The small number of study subjects is one possible explanation for the negative result. Another is relatively poor glycemic control in both groups. Comparison of LV diastolic dysfunction between patients with good glycemic control (HbA1C < 7%) and patients with poor glycemic control (HbA1C ≥ 7%) is necessary to examine the association of glycemic control and LV diastolic dysfunction. Echocardiography was used as a tool to diagnos LV dysfunction. A recent study showed that asymptomatic diabetic patients, even with normal resting LV dimensions and function, experience exercise-induced delayed onset of LV relaxation [5]. Although the predictive value of echocardiography for LV dysfunction is good, it might have not ruled out LV dysfunction completely. Therefore, stress tests, such as treadmill or dobutamine stress echocardiography, could detect
The metabolic syndrome refers to a well defined group of risk factors, including central obesity and inflammation, for the development of diabetes and cardiovascular disease. Interestingly, many studies have recently led to the emergence of somewhat unexpected relationships between several infectious diseases and various aspects of the metabolic syndrome. Our understanding of the mechanisms underlying these interactions is also rapidly developing and some of these are summarized in this article. We will focus first on bacterial infection, and most notably the role of gut microbiota in regulaton of both obesity and inflammation. In particular, we focus on the role of inflammasomes and propose that understanding the role of Toll-like receptors and Nod-like receptors in the pathogenesis of inflammatory disorders with or without infection may provide novel targets for prevention and/or treatment of associated diseases. Secondly, chronic bacterial or viral infection and emerging links with metabolism will be reviewed. Finally, consideratons of biomarkers for metabolic syndrome, in particular lipocalin-2, and their link with infection will be discussed.
Background Hypertension and age are recognized as important risk factors for left ventricular (LV) diastolic dysfunction. Some studies have shown that diabetes itself may also be an independent risk factor for LV diastolic dysfunction, although this is controversial. The aim of this study was to determine the factors associated with LV diastolic dysfunction in patients with type 2 diabetes in the absence of hypertension or ischemic heart disease (IHD). Methods Participants in this study consisted of 65 type 2 diabetes patients (M : F = 45 : 20; mean age 51 [26 to 76] years; mean body mass index [BMI] 25.0 ± 2.5 kg/m2) without hypertension, heart disease, or renal disease. Individuals with ischemic electrocardiographic changes were excluded. LV diastolic function was evaluated by Doppler echocardiographic studies. Results Fifteen patients (23.1%) showed LV diastolic dysfunction on Doppler echocardiographic studies. Patients with LV diastolic dysfunction were older than those without diastolic dysfunction (60.0 ± 2.5 vs. 50.5 ± 1.9 years; P < 0.01). After adjusting for age and sex, BMI was higher (26.6 ± 0.7 vs. 24.6 ± 0.3 kg/m2; P < 0.01) and diabetes duration was longer (9.65 ± 1.48 vs. 4.71 ± 0.78 years; P < 0.01) in patients with LV diastolic dysfunction than in those without diastolic dysfunction. There were no differences in sex, smoking, blood pressure, lipid profiles, hemoglobin A1C, fasting glucose, fasting insulin, or diabetic microvascular complications between the LV diastolic dysfunction group and the normal diastolic function group. After adjusting for age, sex, and BMI, diabetes duration was found to be independently associated with LV diastolic dysfunction (odds ratio 1.38; confidence interval 1.12 to 1.72; P = 0.003). Conclusion These results suggest that diabetes duration may be a risk factor for LV diastolic dysfunction in type 2 diabetic patients without hypertension or IHD.
BACKGROUND:The purpose of the current study was to investigate the association between the level of obesity and physical fitness (PF) during adolescence and the risk factors of metabolic disorders during adulthood.METHODS:In the current analysis, 3,993 Korean adults (mean age, 38.70 +/- 1.69 years) were recruited. The level of body index (BI) and PF were examined during adolescence through high school record, and their health examination data, including systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose (FG), total cholesterol (TC), and current body mass index (BMI) were obtained from National Health Insurance Corporation Data. Gender-specific analyses were administered to compare health exam data across the level of BI, the level of PF, and a mixed level of BI and PF.RESULTS:Most obese males during high school had statistically higher SBP, DBP, FG, and BMI in adulthood, and most obese females had higher BMI, as compared to most lean males or females. Least fit males during high school had statistically higher BMI in adulthood, and least fit females had statistically higher SBP, DBP, FG, TC, and BMI, as compared to most fit males or females. There was a significant relationship between the mixed level of BI and PF and SBP, DBP, TC and current BMI in both genders.CONCLUSION:Maintaining a healthy level of body weight and PF during adolescence is recommended to prevent the development of metabolic diseases in adulthood.
Background Kidney function is critical in homocysteine clearance, and plasma homocysteine level is frequently increased in patients with renal failure. On the other hand, recent studies in animals have shown that hyperhomocysteinemia induces renal injury. In this study, we determined whether hyperhomocysteinemia can be a risk factor for the development of microalbuminuria in patients with type 2 diabetes. Methods A nested case-control study. Of 887 patients with type 2 diabetes who did not have microalbuminuria at baseline, 76 developed microalbuminuria during follow-up (mean, 36.0 ± 11.7 months; range, 18 to 76 months). The control group consisted of 152 age- and sex-matched subjects who did not develop microalbuminuria. Baseline plasma homocysteine concentrations were measured in stored samples. Results Baseline plasma homocysteine concentrations and mean HbA1C levels during follow-up were significantly higher in patients who developed microalbuminuria than in those who remained normoalbuminuric. Multivariate logistic regression analysis showed that baseline plasma homocysteine level and mean HbA1C were independent predictors of microalbuminuria in type 2 diabetes. Conclusion Hyperhomocysteinemia was associated with increased risk of microalbuminuria in patients with type 2 diabetes supporting the concept that hyperhomocysteinemia has an etiologic role in the pathogenesis of diabetic nephropathy.
Dear Respected Members of Korean Diabetes Association, As an official journal of the Korean Diabetes Association (KDA), the Korean Diabetes Journal has been published with the aim of contributing to the study of diabetes through the exchange of up-to-date academic information with foreign scholars as well as association members. The journal has played a leading role in the development of the study of diabetes in South Korea and I thank to the efforts and active participation of our association members. Now is the time when we should take a new leap forward to actively address domestic and foreign research trends that have changed drastically in recent years. Currently, most Korean scholars place top priority on submitting manuscripts to SCI-level journals, as papers published in SCI-level journals are highly rated when evaluating grant applications and evaluating achievements in South Korea. Accordingly, the number of papers published in domestic academic journals is decreasing. Given the current circumstances, unless the Korean Diabetes Journal is listed in international database such as Medline and SCI, we may witness a reduction in the number of submitted papers and thus the lowering of the journal's level. Therefore, publication of our journal in English is not an option, but a necessity. There are Korean-language journals posted on the SCIE, but only based on a temporary special policy, which will not last for a long time. In addition, the continued globalization of the KDA requires the continued exchange of information with scholars around the world, which necessitates the publication of the journal in English. Many of our members see their papers published in SCI-level journals every year. Furthermore, now is the time when our association should embrace a leadership role. Hence, our objective is to disseminate domestic findings regarding the study of diabetes, contribute to medical development, and play to a leading role on the global stage of diabetes. It is expected that many difficulties will occur during the initial stages of this transition, but they may be thought of as a rite of passage we must go through. Our association will not reach the goal of internationalizing or globalizing our journal without the voluntary cooperation of our members. Therefore, I earnestly ask you to contribute English-language papers to our journal, and to refer to papers from our journal in papers that are to be published in other SCI-level journals. Lastly, I thank to all members of KDA for their devotion to the society and wish your health and happiness.
BACKGROUND:The purpose of the current study was to investigate the association of obesity level, physical fitness level, hemoglobin A1c (HbA1c) level and metabolic syndrome (MetS) risk factors among Korean adults.METHODS:A total of 557 adults (272 males and 285 females) who underwent medical check-up at local hospital were recruited. In addition to regular health check-up, cardiopulmonary fitness, muscular endurance were measured and their association were analyzed.RESULTS:The prevalence of MetS was 31.7% for males and 23.7% for females. Females with the higher muscular endurance had lower waist circumference, triglyceride level, and HbA1c level than those with the lower muscular endurance. Males with the higher level of cardiopulmonary fitness had lower diastolic blood pressure, lower high-sensitivity C-reactive protein level and higher high density lipoprotein cholesterol level than males with the lower level of cardiopulmonary fitness. Females with the higher level of cardiopulmonary fitness had lower body weight, body mass index, systolic blood pressure, and fasting blood glucose level than females with the lower level of cardiopulmonary fitness. Participants with the higher level of adiposity and the lower level of physical fitness were 5.26 times (95% confidence interval [CI], 2.19 to 12.62), 5.71 times (95% CI, 2.23 to 14.60) more likely to have MetS, respectively, in male and female compared to participants who were neither obese nor have the lower level of fitness.CONCLUSION:This study suggests that maintaining a healthy body weight as well as a certain level of fitness is important for the prevention of MetS.
BACKGROUND:The main source of carbohydrate in the Korean diet is rice, which is usually served in a rice bowl. This study investigated the impact of a meal plan using smaller rice bowls on dietary energy intake and macronutrient composition in overweight or obese patients with type 2 diabetes mellitus. METHODS:A total of 67 women with type 2 diabetes were enrolled in our study. We divided these participants into three groups: a normal-weight group (NW; body mass index [BMI] < 23 kg/m(2); n = 17), an overweight group (OW; 23 = BMI < 25 kg/m(2); n = 24) and an obese group (OB; BMI >/= 25 kg/m(2); n = 26). Three-day dietary records were analyzed for total energy intake (TEI) and macronutrient composition both before enrollment and two weeks after patients received instruction in a dietary plan based on using a small (200 mL) rice bowl. RESULTS:After the intervention, TEI decreased in the OW and OB groups. Decreased carbohydrate (NW, -4 +/- 5%; OW, -4 +/- 5%; OB, -3 +/- 6%) and increased fat intakes were found in all three groups, which complies with Korean Diabetes Association recommendations. The protein proportion of TEI significantly increased only in the OW group. Body weight decreased both in the OW and OB groups. CONCLUSION:A short-term, small-rice-bowl-based meal plan was effective for body weight control and macronutrient balance in overweight or obese women in Korea with type 2 diabetes.
BACKGROUND:The Korean National Health and Nutrition Examination Surveys reported 65% of daily energy intake (EI) as carbohydrate (CHO) in the Korean population and main source of CHO was cooked rice. We used a standardized-small sized rice bowl for diet education and investigated its effectiveness on body weight, glucose and lipid, compared to the conventional food exchange system in type 2 diabetes obese women. METHODS:Type 2 diabetic women with body mass index >/= 23 kg/m(2) were randomly assigned to small rice bowl-based meal plan (BM) and food exchange-based meal plan (ExM) group. Both groups were asked to reduce their EI by 500 kcal/day for 12 weeks. The macronutrient composition was instructed: 55 to 60% of EI as CHO, 15 to 20% as protein, and 20 to 25% as fat. BM group received only a simple instruction for application of the rice bowl. Nutrient intake was estimated with the 3-day dietary records. RESULTS:Finally, 44 subjects finished the study. The percent reduction of body weight was significant both BM group (-5.1 +/- 2.6%) and ExM group (-4.8 +/- 2.8%) after 12 weeks (P < 0.001) but there was no difference between the groups. There was no difference in the proportional change of CHO, protein and fat in EI between the groups. Additionally, the change of HbA1c and low density lipoprotein-cholesterol were not significantly different between the two groups. CONCLUSION:The BM group was as effective as ExM for body weight and glucose control in type 2 diabetes obese women.
Background There have been no systematic observations regarding changes in early phase insulin secretion among Korean prediabetes and early stage type 2 diabetes mellitus (T2DM) patients. Methods We conducted 75-g oral glucose tolerance tests (OGTT) in 873 subjects with suspected abnormal glucose tolerance. All subjects were diagnosed as having normal glucose tolerance (NGT), prediabetes (preDM), or T2DM according to the OGTT results and the insulin secretory and insulin resistance indices of each subject were calculated. Additionally, we analyzed the changes in early phase insulin secretion according to changes in fasting (Glc0), post-prandial (Glc120) glucose and HbA1c (A1c) levels. Results As compared to subjects with NGT, the insulin secretory indices of the preDM and T2DM subjects progressively declined, and the insulin resistance indices were progressively aggravated. Early phase insulin secretion decreased rapidly according to the increments of Glc0, Glc120 and A1c, and these changes were most prominent in the NGT stage. Compared to the control group, the early phase insulin secretion levels of the preDM or T2DM subjects were less than 50% when Glc0 was over 100 mg/dL, Glc120 was over 145 mg/dL, and A1c was over 5.8%. Conclusion This study suggests that progressive beta cell dysfunction in Koreans may be initiated and rapidly aggravated during the period generally designated as 'normal.'
Background Aerobic exercise can effectively reduce visceral fat. However, few studies have examined the effect of daily physical activity on obesity and cardiopulmonary function in the subjects with diabetes. We examined the effect of moderate intensity of walking in obese diabetes patients by monitoring of daily activity and measuring the change in abdominal fat area, muscle are and maximal muscle strength. Methods We randomly assigned 27 obese women with type 2 diabetes to an aerobic exercise group (AG, n = 13) and control group (CG, n = 14). The AG performed moderate intensity walking for 60 minutes per exercise, 5 times per week, and for 12 weeks. The activity energy expenditure was monitored by a multi-record accelerometer. The CG maintained routine daily activities. At the time of the initiation of the study and after 12 weeks of exercise, the aerobic exercise capacity was assessed using oxygen consumption rate at anaerobic threshold (VO2-AT). The abdominal fat area and the quadriceps muscle area were measured by computed tomography, and the maximum muscle strength of the upper and lower limbs was measured by a chest press and a leg press, respectively. Results The mean age of the study subjects was 56.6 ± 8.0 years, the mean duration of diabetes was 6.3 ± 6.0 years, and the body weight index (BMI) was 27.3 ± 2.7 kg/m2. The BMI of the AG was significantly decreased (P = 0.003). In the AG, the visceral fat area and subcutaneous fat area were also significantly decreased (P = 0.018 and P < 0.001, respectively) but not in CG. VO2-AT of the AG was significantly improved, while that of the CG did not change (P = 0.009 and P = 0.115, respectively). The quadriceps muscle mass and the maximal muscle strength of the AG did not change, however, the CG showed a significant decrease. Duration of moderate intensity exercise was correlated with the decrease in total abdominal fat area (r = -0.484; P = 0.011) and that of high intensity exercise was correlated with improvement of cardiopulmonary function (r = 0.414; P = 0.032). Conclusion Daily moderate intensity aerobic exercise is effective at reducing abdominal fat mass, while high intensity exercise improves cardiopulmonary function.
Cardiovascular (CV) disease, including coronary artery disease (CAD) is the leading cause of death in adults with type 2 diabetes [1], because accompanied other risk factors such as dyslipidemia, hypertension, prothrombic and proinflammatory factors each contribute to accelerated atherosclerosis in obese type 2 diabetes mellitus [2]. Still, the pathophysiologic mechanisms accounting for a substantially increased risk for CAD in adult type 2 diabetes remain unclear. A great efforts for discovery and validation of the novel risk factors in order to potentially identify high-risk individuals that may benefit from aggressive preventive strategies have been performed nowadays.
We would like to express our appreciation to Dr. Won for his letter regarding our manuscript, Lack of association between serum cystatin C level and coronary artery disease in diabetic patients. Cystatin C is a low molecular mass protein that is passed freely through the glomerular membrane. Unlike creatinine, cystatin C is eliminated from circulation almost exclusively by the kidney and is affected less by renal tubular secretion, theoretically making it an ideal marker of glomerular filtration rate. A recent meta-analysis suggested serum cystatin C level as a better indicator of kidney function than serum creatinine level [1]. Cystatin C is produced by all nucleated cells, and its level is independent of body composition, in contrast to creatinine, which is produced almost exclusively by skeletal muscles [2,3]. It has been reported that serum cystatin C level is a strong predictor of mortality and cardiovascular events in elderly patients with chronic renal disease or coronary artery disease (CAD) [4,5]. In addition, Maahs et al. [6] reported a statistically important relationship between serum cystatin C level and CAD in type 1 diabetic patients. In contrast, we found no association between serum cystatin C level and CAD in type 2 diabetic patients [7]. Serum cystatin C level was significantly higher in patients with diabetic nephropathy, both in CAD patients and in non-CAD patients. On the other hand, there was no significant difference in serum cystatin C level between CAD and non-CAD patients, regardless of the presence of diabetic nephropathy. The cause of this discrepancy between studies is not clear, but several other studies have reported similar results to those of our study. Serum cystatin C has been used to predict chronic renal disease, but not CAD [8]. In a study of middle-aged subjects, carotid atherosclerosis was found to be associated with microalbuminuria but not with serum cystatin C level [9]. In addition, a recent study by Maahs et al. [10] also reported that, in persons without diabetes mellitus and having relatively normal renal function, increased cystatin C was associated with decreased, rather than increased, CAD progression. In conclusion, we believe that serum cystatin C level is a useful marker for the assessment of renal function but is not a marker for CAD. However, our study is limited because it was a retrospective case-control study, the study sample was relatively small, and we did not evaluate the associations among cystatin C level and other markers of inflammation or BMI. Further prospective studies with larger sample sizes are needed to evaluate the relationship between serum cystatin C and cardiovascular disease.
New diabetes management systems based on interactive communication have been introduced recently, accompanying rapid advances in information technology; these systems are referred to as "ubiquitous diabetes management systems." In such ubiquitous systems, patients and medical teams can communicate via Internet or telecommunications, with patients uploading their glucose data and personal information, and medical teams sending optimal feedback. Clinical evidence from both long-term and short-term trials has been reported by some researchers. Such systems appear to be effective not only in reducing the levels of HbA1c but also in stabilizing glucose control. However, most notably, evidence for the cost-effectiveness of such a system should be demonstrated before it can be propagated out to the general population in actual clinical practice. To establish a cost-effective model, various types of clinical decision supporting software designed to reduce the labor time of physicians must first be developed. A number of sensors and devices for monitoring patients' data are expected to be available in the near future; thus, methods for automatic interconnections between devices and web charts were also developed. Further investigations to demonstrate the clinical outcomes of such a system should be conducted, hopefully leading to a new paradigm of diabetes management.
