Relationship between Heart Rate Turbulence and Heart Rate Variability in Korean Adults with Structurally Normal Heart

BACKGROUND AND OBJECTIVES: Heart rate variability (HRV) illustrates the autonomic integration of the heart. Depressed HRV has been proven to be associated with an increased risk of cardiac death, whereas heart rate turbulence (HRT) is believed to reflect baroreflex sensitivity and it was recently introduced as another noninvasive tool for risk stratification. The aim of this study was to determine the relationship between the HRT and HRV parameters in Korean adults with a structurally normal heart. SUBJECTS AND METHODS: We studied 61 adults (males: 31) who showed ventricular premature complexes on 24 hour Holter recording and who were found to have normal hearts on full noninvasive investigation. We calculated the mean heart rate (RR interval), the number of VPBs, the time- and frequency-domain HRV parameters and two HRT parameters: turbulence onset (To) and turbulence slope (Ts). RESULTS: Ts showed a strong correlation with the HRV parameters (LF/HF ratio: r=0.35, p=0.006; VLF: r=0.32, p=0.013; LF: r=0.27, p=0.035; SDNN: r=0.28, p=0.029; SDANN: r=0.32, p=0.012), but To showed no significant correlation with the HRV parameters. CONCLUSION: The HRT parameters, and especially Ts, correlate strongly with the HRV parameters; therefore, Ts should be considered as a parameter that reflects the overall cardiac autonomic tone.

Association between two SNPs (+45T>G and +276G>T) of the adiponectin gene and coronary artery diseases / 대한내과학회지

BACKGROUND: Adiponectin, an adipocyte-secreted protein, is known to have anti-atherogenic, anti-inflammatory and anti-diabetic properties. Adiponectin levels are decreased in obesity, type 2 diabetes, and coronary artery disease. Several studies have been performed aiming to investigate the association of genetic variations in the adiponectin with obesity, insulin resistance, and type 2 diabetes but few studies were performed in association with coronary artery disease. Therefore we examined the association between two single nucleotide polymorphisms (SNPs) (+45T>G and +276G>T) of the adiponectin gene and coronary artery diseases (CAD). METHODS: One hundred fifty six subjects were enrolled in which coronary angiograms were performed due to chest pain in Kangbuk Samsung Hospital from April to August, 2003 (97 males, 59 females, mean age 57.40+/-11.15 yrs). Body mass index, fasting blood glucose, lipid profiles were measured in every subject. Single nucleotide polymorphisms (SNPs) in the adiponectin gene were determined by Taqman polymerase chain reaction (PCR) method. The presence of CAD was defined as a >50% reduction of coronary artery diameter. RESULTS: Among 156 subjects, the allele frequencies were 0.683 for G allele and 0.317 for T allele in SNP +276G>T and 0.705 for T allele and 0.295 for G allele in SNP +45T>G. Both genotypes were in compliance with Hardy-Weinberg equlibrium. Mean serum fasting glucose level was significantly higher and mean high-density lipoprotein cholesterol (HDL-C) level was lower in CAD groups (p=0.015, p=0.004). No association with the presence of CAD was observed for adiponectin gene SNP276 and SNP45 (p=0.954, p=0.843). Also, no significant association was observed between the severity of CAD and either SNPs (p=0.571, p=0.955). CONCLUSIONS: Our study showed that SNP +276G>T and +45T>G in adiponectin gene were not associated with the presence of CAD. Further studies will be necessary to confirm the role of SNP 276G>T and 45T>G in the development of CAD.

Concordance/Discordance between Apolipoprotein B Levels and the Cholesterol Indexes

BACKGROUND AND OBJECTIVES: Apolipoprotein B (Apo-B) has been reported to be a better predictor of the coronary artery disease (CAD) than the cholesterol indexes. The aim of this study was to examine the concordance/discordance between the apolipoprotein B levels and the cholesterol indexes, and to assess the factors affecting the discordance. SUBJECTS AND METHODS: A total of 11,816 participants (6,965 men and 4,851 women) were enrolled in this study from all the individuals who participated in medical screening examinations at the health promotion center in Kangbuk Samsung Hospital from January to December 2002. All the participants had no history of coronary artery disease. We assessed the concordance between the biochemical parameters of the atherogenic indexes, and we evaluated the factors affecting the discordance. RESULTS: Despite the fact that the Apo-B and the various cholesterol indexes were highly correlated, the concordance rate was merely 47-56%. Multinomial logistic regression analysis showed the possibility of an increased risk for the group of discordance in whom Apo-B level was disproportionately higher than LDL cholesterol in the elderly, the smokers, the men and the people having a larger waist circumference, a lower total cholesterol level, a higher triglyceride level and a higher HDL-C level. CONCLUSION: The measurement of apo B, along with the measurement of the standard lipid profile, could be a great help in evaluating the CAD risk and for aiding in the treatment of dyslipidemia in the elderly, the smokers, men and the people having a larger waist circumference, a lower total cholesterol level, a higher triglyceride level and a higher HDL-C level.

Assessment of Factors Influencing Plasma BNP Level in Patients with Chronic Atrial Fibrillation and Preserved Left Ventricular Systolic Function

BACKGROUND AND OBJECTIVES: Several studies have reported that Brain Natriuretic Peptide (BNP) were increased in patients with chronic atrial fibrillation (AF). The objective of this study was to assess the factors influencing plasma BNP levels in patients with chronic AF and preserved left ventricular (LV) systolic function. SUBJECTS AND METHODS: Transthoracic echocardiography was performed in 55 patients (25 men, 30 women; mean age 66.6+/-11.5 years) with chronic AF. At the same time, plasma BNP was measured with a Triage(r) kit (Biosite, San Diego, California). RESULTS: Women, long duration of AF and hypertension were more prevalent in the highest quartile group of BNP levels than in the lowest quartile group of BNP levels. Significant correlations were observed between plasma BNP levels and the following: mitral E velocity (r=0.339), mitral annular E'-velocity (r=-0.396), ratio of mitral E-velocity and mitral annular E' velocity (r=0.473), left atrium (LA) size (r=0.648), LA volume index (r=0.744), right atrium (RA) volume index (r=0.554), maximal velocity (Vmax) of mitral regurgitation (MR) (r=0.444), tricuspid regurgitation (TR) Vmax (r=0.544), MR grade (r=0.431), TR grade (r=0.427) and LV mass index (r=0.570). In stepwise multiple linear regression analysis, LA volume index (beta=0.299, p=0.014), LV mass index (beta=0.404, p<0.001) and duration of AF (beta=0.488, p<0.001) independently predicted plasma BNP levels in this study subjects. The patients with increased LA volume index exhibited longer duration of AF, larger RA volume index and LV mass index, higher MR Vmax, TR Vmax, MR and TR grade and plasma BNP level. CONCLUSION: LA volume index, LV mass index and duration of AF were independent predictors of plama BNP level in patients with chronic AF and preserved LV systolic function.

The Relationship between Cardiovascular Risk Factors and the Serum Ferritin Level in Relation to C-Reactive Protein in Korean

BACKGROUND AND OBJECTIVES: Iron is a key component in the production of oxidized low density lipoprotein (LDL), which increases cardiovascular disease through inflammation. However, there is little data to suggest that oxidative stress is positively correlated with C-reactive protein (CRP). The purpose of this study was to examine the influence of the serum ferritin level and cardiovascular risk factors on CRP in a Korean population. SUBJECTS AND METHODS: A total of 808 subjects (465 men, 343 women), who had undergone a medical check-up at the health promotion center at Kangbuk Samsung Hospital, between September 2002 and November 2002, were included in this study. Logistic regression models were computed using elevated or nonelevated hsCRP, as dependent variable, with cardiovascular risk factors, such as, serum ferritin, total, LDL and HDL cholesterols, controlling for potential confounders, including age, gender, body mass index (BMI), hypertension, diabetes and smoking. RESULTS: Significant positive correlations were found between hsCRP and age, BMI, triglyceride and the level of serum ferritin, with a negative correlation found between hsCRP and HDL cholesterol. In age, gender, BMI, hypertension, diabetes, a smoking-adjusted model, an elevated ferritin level were not significantly associated with elevated hsCRP in low LDL subjects (OR=1.68, 95% CI=0.81-3.48), but significant associations were observed in high LDL subjects (OR=11.21, 95% CI=1.14-110.27). And we observed the significant effect modification of the association of hsCRP with serum ferritin level by LDL-cholesterol (p=0.002). CONCLUSION: Our results suggest that increased LDL cholesterol and ferritin have an effect on the increment of hsCRP. Thus, iron-catalyzed oxidation of LDL cholesterol may be an important step of the development of the inflammatory process. Further prospective studies will need to be performed to establish the relationship between the decreasing of the serum ferritin level and CRP for the prevention of cardiovascular disease.

Seasonal Variation in Insulin Resistance in Koreans

BACKGROUND AND OBJECTIVES: There is a seasonal variation in the incidence of diabetes mellitus and cardiovascular disease. Insulin resistance is important in the development of both non-insulin dependent diabetes mellitus (Type II DM) and cardiovascular disease. Hyperinsulinemia, induced by an insulin resistant state, causes the development of a chronic inflammatory response in vascular structures, which is one of the main causes of cardiovascular disease. There have been several studies on seasonal variation in insulin resistance. Therefore, seasonal variation in insulin resistance were investigated to discover if any relationship existed. SUBJECTS AND METHODS: Korean people examined at a health care center were included. The subjects were divided into four groups, according to the season, and a homeostasis model assessment index (HOMA) calculated, as an indicator of insulin resistance, and compared between the groups. RESULTS: Using the homeostasis model assessment, the highest insulin resistance was observed during winter. Also, the body mass index and waist-hip ratio were highest during winter. CONCLUSION: Compensating for other metabolic factors (age, gender, body mass index, waist-hip ratio and season), insulin resistance was still found to be higher during winter. Seasonal variation in insulin resistance can be associated with the incidence of DM or cardiovascular disease. Therefore, a prospective study will be needed.

Effect of Exercise on Serum C-Reactive Protein

BACKGROUND AND OBJECTIVES: Regular exercise protects us against numerous chronic diseases, and reduces the risk of cardiovascular disease. Also, C-reactive protein, a marker of inflammation, is known to be associated with the risk and prognosis of cardiovascular disease. The present study was designed to assess the effects of regular exercise on the level of high sensitive C-reactive protein (hsCRP). SUBJECTS AND METHODS: The serum level of hsCRP and the anthropometric indices of adiposity, metabolic variables, blood pressure (BP) and several cardiovascular risk factors were measured in 18445 subjects. A prospective study of 42 subjects with high baseline levels of hsCRP was conducted. After 3 months of regular aerobic exercise their hsCRP levels were rechecked and the association between regular exercise and hsCRP analyzed using a cross sectional and prospective study. RESULTS: Age, smoking, hypertension, diabetes and body mass index were found to be independent determinants of an elevated hsCRP level, but exercise was not found to be associated with a decreased hsCRP level in the cross-sectional study. In the prospective study, the mean serum hsCRP value was significantly reduced after 3 months in the exercise group (3.02+/-1.06 vs. 2.05+/-1.23 p=0.015), but not in the controls (3.03+/-1.09 vs. 2.57+/-1.11 p=0.104). However, the interval changes in hsCRP levels were not different in the exercise compared to the control group (p=0.660). CONCLUSION: These results suggest that exercise is not an independent determinant of the CRP level. Three months of regular aerobic exercise show a tendency to be associated with a reduction in the hsCRP level, but this putative effect of exercise on the hsCRP level was not significant in healthy subjects. Further larger sample, prospective cohort studies will be required to establish the effect of exercise on the hsCRP level.

Relationship between Heart Rate Reduction and Insulin Resistance in Normoglycemic Individuals

BACKGROUND AND OBJECTIVES: It is well known that, regardless of whether a person has cardiovascular diseases, the reduction of heart rate after exercise reflects the impairment of the autonomic nervous system. It is also a predictive factor of death rate and it correlates to insulin resistance. Therefore, we assessed these correlations in normoglycemic subjects. SUBJECTS AND METHODS: Exercise stress testing was performed according to the Bruce protocol. Anthropometric indices of adiposity, metabolic variables, blood pressure (BP) and several cardiovascular risk factors were measured. The HOMA index was used as the insulin resistance, and the impairment of the autonomic nervous system was assessed by measuring the reduction of heart rate for 2 minutes after the cessation of exercise. RESULTS: The reduction of heart rate during 2 minutes after the cessation of exercise statistically correlated with the HOMA index, gender, age, body mass index, the waist circumference, heart rate during rest, the maximum heart rate, serum total cholesterol concentration, serum high density lipoprotein cholesterol concentration and serum low density lipoprotein cholesterol concentration, (p<0.05). However, on multiple regression analysis, the HOMA index, gender, heart rate during rest, and the maximum heart rate significantly correlated to the reduction of heart rate during 2 minutes after the cessation of exercise. CONCLUSION: In individuals with normal serum glucose levels, even after adjustment was made for other factors, the reduction of heart rate after the cessation of exercise correlated to insulin resistance. Hence, in individuals with normal serum glucose levels, efforts to improve insulin resistance have to be made, and prospective study on this subject is required.

The Relationship between the Serum Intercellular Adhesion Molecule-1 Level and the Prognosis of the Disease in Lung Cancer

BACKGROUND: Adhesion molecules are related to cell-to-cell interaction and inflammatory interaction. In addition, adhesive interactions between tumor cells and adjacent cells and/or extracellular matrix play important roles in the complex process of tumor growth and development. Among these adhesion molecules, expression of intercellular adhesion molecule-1 (ICAM-1) has been identified in colon cancer, bladder cancer, lung cancer, melanoma, pancreatic cancer and hepatocellular carcinoma. In the current study, we analyzed serum ICAM-1 concentrations to investigate the relationship between the serum ICAM-1 level and prognosis in patients with lung cancer METHODS: Serum ICAM-1 was measured in 84 patients with lung cancer according to the pathologic type and clinical stage using the ICAM-1 ELISA kit. The Kaplan-Meier method was used to analyse survival time. RESULTS: There was no difference in serum ICAM-1 concentration among the different stages of lung cancer. Furthermore, there was no difference observed between histologic tumor type with regard to serum ICAM-1 concentration. Although the difference was not significant, the overall survival times of patients with a low serum ICAM-1 concentration ( or=306 ng/mL) in non-small cell lung cancer patients. CONCLUSION: These results suggest that high levels of serum ICAM-1 reflect poor prognosis for patients with non-small cell lung cancer.

The Relationship of the Hypertension, Insulin Resistance, and Metabolic Syndrome in the Serum Uric Acid Level

BACKGROUND AND OBJECTIVE: The relationship between serum uric acid and metabolic syndrome variables has not been reported in Korea. Therefore, whether the circulating levels of serum uric acid are independently related to hypertension, insulin resistance and the variables of metabolic syndrome were assessed. SUCJECTS AND METHODS: A total of 53,477 health screen examinees were enrolled and divided into four groups (Quartile 1:6.29 mg/dL) according to their serum uric acid level. The blood pressure, lipid profiles, fasting plasma glucose, waist circumference, HOMA, high sensitivity CRP and apolipoprotein were compared between the four groups. RESULTS: There was a positive association between blood pressure and the serum uric acid level (p<0.001). After adjustment for covariates the prevalence of hypertension due to uric acid was 1.192 (95% CI, 1.038-1.368 p=0.013), and 1.408 (95% CI, 1.221-1.623 p<0.001) times higher in subjects in the third and fourth uric acid level quartiles, respectively, compared to the subjects in the first quartile. Insulin resistance and metabolic syndrome variables were positively correlated with the serum uric acid level. The number of metabolic syndrome variables was also increased with an elevated serum uric acid level. CONCLUSION: Our study suggests that serum uric acid levels were independently associated with hypertension, insulin resistance and the variables of metabolic syndrome in the Korean population. Although the serum uric acid level was normal value, the risk of metabolic syndrome was increased with an elevated serum uric acid level. However, because of the cross-sectional nature of our study, these findings should be confirmed in prospective cohort studies.

The Relationship between the serum intercellular adhesion molecule-1 level and the prognosis of the disease in lung cancer / 대한내과학회지

BACKGROUND: Adhesion molecule is related to cell-cell interaction and inflammatory interaction. In addition, adhesive interactions between tumor cells and adjacent cells and/or extracellular matrix are important role in the complex process of tumor growth and develpment. Of these adhesion molecules, expression of intercellular adhesion molecule-1 (ICAM-1) have been identified in colon cancer, bladder cancer, lung cancer, melanoma, pancreatic cancer, hepatocellular carcinoma. In the current study, we analyzed serum ICAM-1 concentrations to investigate the relationship between the sICAM-1 level and the prognosis of the disease in patients with lung cancer METHODS: Serum sICAM-1 was measured in 84 patients with lung cancer according to the pathologic types and clinical staging using ICAM-1 ELISA kit. The Kaplan-Meier method was used to analyse survival time. RESULTS: There was no difference in sICAM-1 concentration among the stage of lung cancer. And no difference was observed among histologic tumor types with regard to sICAM-1 concentration. The overall survival of patients with low sICAM-1 concentration (or=306 ng/mL) in non-small cell lung cancer patients, but no difference was observed in small cell lung cancer patients. CONCLUSION: These results suggest that high levels of sICAM-1 reflect the poor prognosis of patients with non-small cell lung cancer.

B-Type Natriuretic Peptide Blood Concentrations in Differential Diagnosis of Dyspnea and its Association to 6 Minute Walk

BACKGROUND AND OBJECTIVES: This study was performed to, 1) evaluate the diagnostic value of the Brain Natriuretic Peptide (BNP), which is known to be present in the heart ventricle, for patients with dyspnea for the assessing its causes;diastolic or systolic heart failure or pulmonary disease, and 2) find if the BNP is correlated with the distance walked in 6 minutes, which is known to be a prognostic indicator for heart failure. SUBJECTS AND METHODS: Fifty-seven patients who admitted to the Kangbuk Samsung Medical Center, with the chief complaint of dyspnea, were enrolled in the study. The subjects were classified into three groups according to the causes of their dyspnea, which were systolic heart failure, diastolic heart failure and chronic obstructive pulmonary disease. The plasma BNP levels were measured by a radioimmunoassay, both at admission and discharge. The BNP levels at admission were compared among the three groups. The presence of a correlation between the distance walked in 6 minutes and the BNP at discharge were also evaluated. RESULTS: The patients group with systolic heart failure had the highest mean BNP concentration of 934.6+/-386.7 pg/mL. The other two groups had significantly lower levels of BNP. The patients group with chronic obstructive pulmonary disease had significantly lower level than the group with diastolic heart failure (33.2+/-25.6 vs. 181.8+/-222.2 pg/mL). The BNP concentrations at discharge, and the distance walked in 6 minutes, between the three groups showed no statistical significance (p=0.69). CONCLUSION: This study showed that the mean plasma BNP level was highest in the group with systolic heart failure, followed by diastolic heart failure and lastly chronic obstructive pulmonary disease. These findings suggest that diagnostic value of the plasma BNP concentration in the assessment of the causes of dyspnea. Although this study has failed to show a correlation between the plasma BNP concentration at discharge and the distance walked in 6 minutes, prospective cohort studies, with larger sample sizes, need to be performed to establish the relationship, if any.

Sex difference in the relationship between insulin resistance and QTc interval in Korean non-diabetic subjects / 대한내과학회지

BACKGROUND: Men with prolonged corrected QT interval (QTc) are at increased risk for cardiovascular mortality and sudden death, even in healthy person. Also prolonged QTc predicts the mortality in diabetic persons. However the relationship between insulin resistance and QTc is not well known in healthy people without diabetes. This study was performed to observe the association between QTc and insulin resistance in Korean non-diabetic subjects. METHODS: Total 874 subjects (520 men, 354 women, mean age 45.9+/-11.0 years) who underwent medical check-up at health promotion center in Kangbuk Samsung Hospital from January 2002 to May 2002 were included in this study. Age, sex, height, body weight, blood pressure, blood cholesterol, triglyceride, HDL cholesterol, fasting insulin, and fasting glucose levels were measured. QT intervals were corrected with Bazett's formula (QTc=QT/ RR). HOMA (Homeostasis model assessment) were calculated in order to assess the correlations between insulin resistance indices and QTc interval. RESULTS: The means of QTc intervals were significantly longer in females (417.0+/-24.0 msec) compared to males (402.4+/-22.7 msec)(p<0.001). Significant positive correlation were found between QTc and age, glucose, blood pressure in male subjects. There were a positive correlation between QTc and age, glucose, blood pressure, blood chlesterol, LDL-cholesterol, triglyceride, fasting insulin, HOMA index and negative correlation between QTc and HDL-cholesterol in female subjects. With multiple regression analysis, age (beta=0.480, p<0.001) and diastolic blood pressure (beta=0.280, p<0.001) were predictors of QTc in men, age (beta=0.321, p=0.008), diastolic blood pressure (beta=0.324, p=0.006) and HOMA index (beta=3.508, p=0.033) were predictors of QTc in women. CONCLUSION: This study shows that QTc was more prolonged in female than in male among Korean healthy persons. In normoglycemic female subjects, there was correlation between insulin resistance and the prolongation of QTc.

Thyroid Dysfunction and Their Relation to Cardiovascular Risk Factors such as Lipid Profile, hsCRP, and Waist Hip Ratio in Korea

BACKGROUND: Thyroid abnormalities affect a considerable portion of the population, and overt hypothyroidism is associated with an elevated risk of cardiovascular disease and adverse changes in blood lipids. Subclinical hypothyroidism is also associated with an increase risk of cardiovascular disease. So, we undertook this study to investigate the prevalence of overt and subclinical thyroid disorders and their associations with cardiovascular risk factors. METHODS: This study involved 66260 subjects (43588 men, 22672 women ; between 20~80 years of age, mean age 41.5 +/- 9.6). Serum free thyroxine (FT4), thyroid stimulating hormone (TSH), total cholesterol, low density lipoprotein cholesterol (LDL-C), and high density lipoprotein cholesterol (HDL-C) were measured by RIA using commercial kits. High sensitivity C-reactive protein (hsCRP) levels were determined by nephelometry. RESULTS: The prevalences of overt thyrotoxicosis, subclinical thyrotoxicosis, overt hypothyroidism and subclinical hypothyroidism were 5/1000 (334 subjects), 6.4/1000 (426 subjects), 1.6/1000 (108 subjects), and 6.4/1000 (375 subjects). Mean plasma total cholesterol and LDL-C were elevated in overt hypothyroidism than in normal controls (202.1 mg/dL and 121.8 mg/dL versus 197.1 mg/dL and 120.1 mg/dL, respectively) (p< 0.05). In subclinical hypothyroidism, mean total cholesterol and LDL-C levels were also elevated (201.9 mg/dL and 123.7 mg/dL) (p=0.015, p=0.047). Waist-to-hip ratio (WHR) was lower in overt thyrotoxicosis and higher in hypothyroidism. CONCLUSION: The prevalence of thyroid dysfunction in Korea is not significantly different from that reported by other countries. It was also age dependent and higher in women, but this elevation in women was lower than expected. Patients with hypothyroidism exhibited higher waist-to-hip ratios, an index of obesity. Patients with subclinical hypothyroidism exhibited elevated atherogenic parameters (Total cholesterol, LDL-C). Therefore screening and treatment for subclinical hypothyroidism may be warranted due to its adverse effects on lipid metabolism.

Prevalence of Helicobacter pylori infection and its association with cardiovascular risk factors in Korean adults / 대한내과학회지

BACKGROUND: Chronic inflammation plays an important role in the pathophysiology of atherosclerosis. Among the many pathogens causing chronic inflammation, Helicobacter pylori is the major pathogen for gastric diseases in Korean people. The purpose of this study is to evaluate the prevalence of Helicobacter pylori infection and its association with cardiovascular risk factors in healthy Korean adults. METHODS: In 32,998 healthy subjects, the proportion of seroposive subjects for H. pylori and its association with cardiovascular risk factors were evaluated in participants in health screening program. H. pylori infection status was tested with serum IgG antibody test with ELISA and blood pressure, body mass index, serum lipid profiles, hsCRP were tested. RESULTS: 67% of participants were infected with H. pylori serologic test. Seropositivity was highest in age group of over sixty and male subjects tended to be more infected with H. pylori (p0.05). In multiple logistic regression models, adjusted by age, sex and other variables, total cholesterol was associated with H. pylori seropositivity (odds ratio 1.004, 95% confidence intervals 1.002~1.006, p<0.001) and HDL was inversely related with H. pylori independently (odds ratio 0.990, 95% confidence intervals 0.987~0.992, p<0.001). Age and sex was also positively associated with H. pylori (odds ratio for age 1.029, 95% confidence intervals 1.026~1.032, p<0.001, odds ratio for women to men 0.818, 95% confidence intervals 0.750~0.893, p<0.001). CONCLUSION: The results of this study is that H. pylori infection is prevalent in Korean adults and is independently correlated with cardiovascular risk factors such as total cholesterol and HDL in atherogenic way in healthy subjects. This may support the previous hypothesises that H. pylori might be one of the atherosclerotic pathogens.

Thyroid dysfunction and their relation to cardiovascular risk factors such as lipid profile, hsCRP, waist hip ratio in Korea / 대한내과학회지

BACKGROUND: Thyroid abnormalities affect a considerable portion of the population. Overt hypothyroidism is associated with an elevated risk of cardiovascular disease and adverse changes in blood lipids. Subclinical hypothyroidism is also associated with an increase risk of cardiovascular disease. So we performed the study to investigate the prevalence of overt and subclinical thyroid disorders and their association between cardiovascular risk factors. METHODS: This study was performed in 66,260 subjects (43,588 men, 22,672 women ; between 20~80 years of age, mean age 41.5+/-9.6). Serum free thyroxine (FT4), thyroid stimulating hormone (TSH), total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) were measured with RIA using commercial kits. High sensitivity C-reactive protein (hsCRP) were measured with nephelometry. RESULTS: The prevalence of overt thyrotoxicosis, subclinical thyrotoxicosis, overt hypothyroidism and subclinical hypothyroidism was 5/1000 (334 subjects), 6.4/1000 (426 subjects), 1.6/1000 (108 subjects), 6.4/1000 (375 subjects) population. Mean plasma total cholesterol and LDL-C were elevated in overt hypothyroidism than normal (202.1 mg/dL and 121.8 mg/dL versus 197.1 mg/dL and 120.1 mg/dL)(p < 0.05). Also in subclinical hypothyroidism, mean total cholesterol and LDL-C level were elevated compared to normal group (201.9 mg/dL and 123.7 mg/dL)(p=0.015, p=0.047). Waist-to-hip ratio (WHR) was lower in overt thyrotoxicosis and was higher in hypothyroidism. CONCLUSION: The prevalence of thyroid dysfunction was not significantly different from those of other countries. It was also age dependent and higher in women but it was lower than expected. Patients with hypothyroidism exhibit higher levels of waist-to-hip ratio as index of obesity. Patients with subclinical hypothyroidism exhibited increased levels of the atherogenic parameters (Total cholesterol, LDL-C). Therefore screening and treatment for subclinical hypothyroidism may be warranted due to the adverse effects on lipid metabolism.

Thyroid dysfunction and their relation to cardiovascular risk factors such as lipid profile, hsCRP, waist hip ratio in Korea / 대한내과학회지

BACKGROUND: Thyroid abnormalities affect a considerable portion of the population. Overt hypothyroidism is associated with an elevated risk of cardiovascular disease and adverse changes in blood lipids. Subclinical hypothyroidism is also associated with an increase risk of cardiovascular disease. So we performed the study to investigate the prevalence of overt and subclinical thyroid disorders and their association between cardiovascular risk factors. METHODS: This study was performed in 66,260 subjects (43,588 men, 22,672 women ; between 20~80 years of age, mean age 41.5+/-9.6). Serum free thyroxine (FT4), thyroid stimulating hormone (TSH), total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) were measured with RIA using commercial kits. High sensitivity C-reactive protein (hsCRP) were measured with nephelometry. RESULTS: The prevalence of overt thyrotoxicosis, subclinical thyrotoxicosis, overt hypothyroidism and subclinical hypothyroidism was 5/1000 (334 subjects), 6.4/1000 (426 subjects), 1.6/1000 (108 subjects), 6.4/1000 (375 subjects) population. Mean plasma total cholesterol and LDL-C were elevated in overt hypothyroidism than normal (202.1 mg/dL and 121.8 mg/dL versus 197.1 mg/dL and 120.1 mg/dL)(p < 0.05). Also in subclinical hypothyroidism, mean total cholesterol and LDL-C level were elevated compared to normal group (201.9 mg/dL and 123.7 mg/dL)(p=0.015, p=0.047). Waist-to-hip ratio (WHR) was lower in overt thyrotoxicosis and was higher in hypothyroidism. CONCLUSION: The prevalence of thyroid dysfunction was not significantly different from those of other countries. It was also age dependent and higher in women but it was lower than expected. Patients with hypothyroidism exhibit higher levels of waist-to-hip ratio as index of obesity. Patients with subclinical hypothyroidism exhibited increased levels of the atherogenic parameters (Total cholesterol, LDL-C). Therefore screening and treatment for subclinical hypothyroidism may be warranted due to the adverse effects on lipid metabolism.