Healthy Twin Study Research Articles

Relationship between Serum Testosterone Level and Carotid Intima-Media Thickness among Korean Men and Postmenopausal Women.

Given that the role of serum testosterone on incident cardiovascular disease has been uncertain, it is necessary to find out the relationship between serum testosterone and carotid atherosclerosis. The study participants included 1,302 Korean adults (873 men and 429 postmenopausal women) who participated in the Healthy Twin Study and were not receiving androgen deprivation therapy. The participants were classified into three groups: men aged <40 and ≥40 years and postmenopausal women. Total testosterone (TT) and sex hormone-binding globulin (SHBG) concentrations were measured using electrochemiluminescence immunoassays, and free testosterone (cFT) levels were calculated using Vermeulen's method. Carotid intima-media thickness (IMT) was measured at three levels using a high-resolution B-mode ultrasound equipped with a 7-MHz linear transducer. The associations between sex hormone concentrations and carotid IMT were evaluated using a mixed linear regression analysis. After adjusting for cardiovascular risk factors, TT was found to be inversely associated with common carotid IMT in men aged ≥40 years, with a 4.5% decrease in common carotid IMT for every one-standard deviation increase in TT concentration (P=0.0063). In contrast, TT was not significantly associated with carotid IMT in all segments in men aged <40 years and postmenopausal women. Additionally, SHBG and cFT were not associated with carotid IMT in any segment. The significant association between TT level and common carotid IMT in men aged ≥40 years suggests that decreased testosterone levels are involved in the development of atherosclerosis in men.

Comparison of Concordance of Peptic Ulcer Disease, Non-Adenomatous Intestinal Polyp, and Gallstone Disease in Korean Monozygotic and Dizygotic Twins: A Cross-Sectional Study.

Epidemiological studies have suggested the role of multiple genetic and environmental factors in the development of non-neoplastic gastrointestinal (GI) diseases; however, little information is available on these factors in the Korean population. Therefore, this cross-sectional study explored the effect of these factors by analyzing the concordance of several benign GI disorders in 525 monozygotic twins compared to that in 122 dizygotic twins aged >20 years from the Healthy Twin Study data of the Korean Genome and Epidemiology Study (2005–2014). Chi-square test, Wilcoxon rank-sum, and binomial and multinomial logistic regression models were used for statistical analysis. There was lack of concordance of gastric/duodenal ulcers and cholelithiasis/cholangitis between monozygotic twins compared to that in dizygotic twins, suggesting that environmental factors may mediate those concordant disease expressions in monozygotic twins. The concordance of intestinal polyps in monozygotic twins was 32% lower than that in dizygotic twins (p = 0.028), indicating that the effect of genetic factors on the risk for intestinal polyp development may be low. In conclusion, the lack or low concordance of several benign GI diseases between monozygotic and dizygotic twin groups suggests the relative importance of environmental factors, indicating that these are preventable diseases.

Comparison of the Coincidence of Osteoporosis, Fracture, Arthritis Histories, and DEXA T-Score between Monozygotic and Dizygotic Twins: A Cross-Sectional Study Using KoGES HTS Data.

We explored the genetic and environmental inter-relationships among osteoporosis, fracture, arthritis, and bone mineral density concordance in monozygotic twins compared to those in dizygotic twins. This cross-sectional research assessed data of 1032 monozygotic and 242 dizygotic twin pairs aged >20 years included in the Healthy Twin Study data of the Korean Genome and Epidemiology Study between 2005 and 2014. Outcomes of interest included illness concordance and absolute differences in dual-energy X-ray absorptiometry (DEXA) T-scores. We found comparable concordances of osteoporosis, fractures, osteoarthritis, and rheumatoid arthritis between monozygotic and dizygotic twins. Medical histories of osteoporosis, fractures caused by accident or falling, osteoarthritis, and rheumatoid arthritis were not distinct between monozygotic and dizygotic twins. Accidental fracture occurrence in both monozygotic twins showed significantly lower odds than that in dizygotic twins. Genetic influence on liability to fracture risk might thus be maintained. DEXA T-scores for bone mineral density indicated more comparable tendencies within monozygotic twin pairs than within dizygotic ones, suggesting the relative importance of genetic contribution to bone mineral density. The relative importance of genetic factors in bone mineral density is sustained between monozygotic twins; overt disease expression of osteoporosis, fractures, or arthritis may be affected by environmental factors.

The relationship between serum sex hormone and cardiac echocardiographic findings in healthy men

Serum sex hormones are known to be associated with cardiovascular disease (CVD), but effects in healthy men on cardiac function have not been well quantified. The authors sought to evaluate an association of sex hormones with cardiac structure and function. Study participants were 857 Korean men without significant cardiovascular diseases participating in the Healthy Twin Study. We estimated the associations of total testosterone (TT) and sex hormone-binding globulin (SHBG) with cardiac structure and function measured by echocardiography using a linear mixed regression model with consideration of random and fixed effects of covariates. The ratio of peak early diastolic velocity of mitral inflow over peak early diastolic mitral annular velocity (E/e’) and left atrial volume index (LAVI), functional parameters reflecting left ventricle (LV) filling pressure, were inversely associated with TT even after further cross-adjustment for SHBG level. There was a positive association between LAVI and SHBG, regardless of TT adjustment. These findings suggest that serum testosterone level is positively associated with LV diastolic function independent of SHBG level.

Causal relationship between the timing of menarche and young adult body mass index with consideration to a trend of consistently decreasing age at menarche.

Younger age at menarche (AAM) is associated with higher body mass index (BMI) for young women. Considering that continuous trends in decreasing AAM and increasing BMI are found in many countries, we attempted to assess whether the observed negative association between AAM and young adult BMI is causal. We included 4,093 women from the Korean Genome and Epidemiology Study (KoGES) and Healthy twin Study (HTS) with relevant epidemiologic data and genome-wide marker information. To mitigate the remarkable differences in AAM across generations, we converted the AAM to a generation-standardized AAM (gsAAM). To test causality, we applied the Mendelian randomization (MR) approach, using a genetic risk score (GRS) based on 14 AAM-associated single nucleotide polymorphisms (SNPs). We constructed MR models adjusting for education level and validated the results using the inverse-variance weighted (IVW), weighted median (WM), MR-pleiotropy residual sum and outliers test (MR-PRESSO), and MR-Egger regression methods. We found a null association using observed AAM and BMI level (conventional regression; -0.05 [95% CIs -0.10–0.00] per 1-year higher AAM). This null association was replicated when gsAAM was applied instead of AAM. Using the two-stage least squares (2SLS) approach employing a univariate GRS, the association was also negated for both AAM and gsAAM, regardless of model specifications. All the MR diagnostics suggested statistically insignificant associations, but weakly negative trends, without evidence of confounding from pleiotropy. We did not observe a causal association between AAM and young adult BMI whether we considered the birth cohort effect or not. Our study alone does not exclude the possibility of existing a weak negative association, considering the modest power of our study design.

Genome-wide association study of non-tuberculous mycobacterial pulmonary disease

BackgroundThe prevalence of non-tuberculous mycobacterial pulmonary disease (NTM-PD) is increasing in South Korea and many parts of the world. However, the genetic factors underlying susceptibility to this disease remain elusive.MethodsTo...

Urinary Sodium and Potassium Levels and Blood Pressure in Population with High Sodium Intake.

The purpose of this study was to examine the association of urinary sodium-to-creatinine ratio and potassium-to-creatinine ratio with blood pressure in a cross-sectional study comprising Korean adults who participated in the Healthy Twin Study. The participants consisted of 2653 men and women in the Healthy Twin Study aged ≥19 years. Participants’ urinary excretion of sodium, potassium, and creatinine was measured from overnight half-day urine samples. Food intake was assessed using a validated food frequency questionnaire. We examined systolic and diastolic blood pressures according to sodium- or potassium-to-creatinine ratios using the generalized linear model. We determined food groups explaining high urinary sodium- or potassium-to-creatinine ratio using the reduced rank regression and calculated sodium- or potassium-contributing food score. We observed that systolic blood pressure was higher among men and women in the highest quintile of urinary sodium-to-creatinine ratio or sodium-to-potassium ratio than it was in the lowest quintile. Geometric means (95% CIs) of the lowest and the highest quintiles of systolic blood pressure (mmHg) were 113.4 (111.8–115.0) and 115.6 (114.1–117.2; P for trend = 0.02), respectively, for sodium-to-creatinine ratio. The association between urinary sodium-to-creatinine and systolic blood pressure was more pronounced among individuals whose body mass index (BMI) was less than 25 kg/m2 (P for interaction = 0.03). We found that vegetables, kimchi and seaweed intake contributed to high sodium intake and a sodium-contributing food score were associated with increased blood pressure. In our study, we identified the food groups contributing to high sodium intake and found that high urinary sodium levels were associated with increasing blood pressure among Korean adults.

Heritability of macular ganglion cell inner plexiform layer thickness as determined by optical coherence tomography: the Healthy Twin Study

PurposeTo evaluate genetic influence on macular ganglion cell inner plexiform layer (GCIPL) thickness.MethodsMacular GCIPL thickness was measured with optical coherence tomography in nine macular subfields defined by the E TDRS....

Heritability of Inner Retinal Layer and Outer Retinal Layer Thickness: The Healthy Twin Study

The purpose of the study is to evaluate the heritability of inner retinal layer (IRL) and outer retinal layer (ORL) thicknesses in the healthy Korean population. This was a cross-sectional, twin and family study. We included 374 Korean adults with healthy eyes from 89 families. IRL thickness (from the internal limiting membrane to the external limiting membrane) and ORL thickness (from the external limiting membrane to the outer border of the retinal pigment epithelium layer) were measured in the nine macular subfields as defined by the Early Treatment of Diabetic Retinopathy Study using optical coherence tomography. The heritability on IRL and ORL thicknesses were investigated using a variance decomposition model. The heritability of IRL thickness was 0.87, 0.58, 0.85, 0.89, and 0.74 for the central, inner superior, inner inferior, inner temporal, inner nasal subfields, respectively; and 0.62, 0.83, 0.62, and 0.60 for the outer superior, outer inferior, outer temporal, outer nasal subfields, respectively. The heritability of ORL thickness was 0.56, 0.75, 0.66, 0.72, and 0.56 for the central, inner superior, inner inferior, inner temporal, inner nasal subfields, respectively; and 0.64, 0.63, 0.73, 0.54 for the outer superior, outer inferior, outer temporal, and outer nasal subfields, respectively. The heritability estimates of IRL thickness and ORL thickness ranged from moderate to high. The IRL thickness at the central, inner temporal, and inner inferior subfields had particularly high heritability.

Potentially modifiable blood triglyceride levels by the control of conventional risk factors

BackgroundsTriglyceride (TG) is known to be regulated by multiple lifestyle factors rather than genetic factors. This cross-sectional and community-based study (Healthy Twin study in Korea) aimed to estimate the “modifiable TG level” by identifying non-genetic risk factors of TG.MethodsParticipants were recruited between 2006 and 2011 who fulfilled health examinations and detail surveys: 3079 Korean adults including 949 monozygotic twins and 222 dizygotic twins. In order to investigate conventional risk factors, a mixed model accounting for family as a random effect was performed. In addition, we conducted a co-twin control analysis for 452 monozygotic twin (MZ) pairs, to examine non-genetic risk factors and potentially modifiable serum triglyceride levels.ResultsAfter excluding patients on dyslipidemia or diabetes medication, 2672 individuals (1029 men, with mean age of 43.9; and 1643 women with mean age of 43.3; 949 MZ pairs, 222 dizygotic twin pairs, and 1501sibling pairs) were analyzed. Fasting blood sugar (FBS), lipid panel, height, weight, waist (WC) and hip circumference, body mass index (BMI), amount of dietary intake and amount of physical activity was examined after adjusting for age and sex. For conventional analysis, WC, fat %, and BMI were identified as significant factors influencing serum triglyceride levels. Examination of non-genetic factors from the Co-twin control study revealed BMI (beta coefficient 9.94 with C.I. 3.42 to 16.46) and amount of alcohol intake (beta coefficient 0.08 with C.I. 0.02 to 0.14) as significant factors.ConclusionOur findings suggest that controlling body weight and alcohol intake might be effective to control TG; moderate weight control (BMI 1 reduction) and reducing alcohol consumption by 50 g/week (about two glassed of beer) might reduce TG level by 9.94 and 4.0 mg/dL.

Eating behavior and metabolic syndrome over time.

We evaluated the longitudinal associations between eating behaviors (EB) and risk of metabolic syndrome (MetS). We obtained complete data on EB, assessed using the Dutch Eating Behavior Questionnaire, and MetS components at baseline and follow-up. Participants included 1876 individuals (704 men, 1172 women; mean age, 45.0 ± 12.8years) from those participating in the Korean Healthy Twin study. A generalized estimating equation model was applied, with sociodemographic factors, health-related factors, follow-up interval, and EB (baseline and changes over time) as independent factors. MetS at baseline was 21.5%, while incident MetS and persistent MetS were 12.0% and 66.6%, respectively, at the 3.13 ± 1.38years follow-up period. In men, baseline restrained EB had positive associations with concurrent MetS (odds ratio [95% confidence interval] per 1 point increase in the score, 1.55 [1.33-1.81]) and persistent MetS (1.53 [1.16-2.01]); baseline external EB and change in external EB had positive associations with persistent MetS (1.56 [1.04-2.33], 1.37 [1.01-2.22], respectively). In women, baseline restrained EB had a positive association with concurrent MetS (1.14 [1.01-1.30]); baseline external EB had an inverse association with persistent MetS (0.71[0.52-0.98]); baseline emotional EB had positive associations with concurrent, incident, and persistent MetS (1.23 [1.01-1.50], 2.14 [1.50-3.06], and 1.92 [1.40-2.64], respectively); and change in emotional EB had positive associations with incident and persistent MetS (1.50 [1.05-2.15], 1.62 [1.14-2.29], respectively). Higher restrained and external EB, and an increase in external EB in men; and higher restrained and emotional EB, and an increase in emotional EB in women may be associated with increased risk of concurrent, incident, or persistent MetS. III, cohort study.

Genetic influence on serum 25-hydroxyvitamin D concentration in Korean men: a cross-sectional study

BackgroundHypovitaminosis D is prevalent worldwide. It is more prevalent in Eastern Asia region, including Korea. In addition to various environmental factors that influence serum 25-hydroxyvitamin D (25(OH)D) concentration, genetic influence also plays a significant role based on studies estimating the heritability of 25(OH)D in non-Asian populations. The objective of this study was to determine the genetic influence on serum 25(OH)D concentration in Korean men using the twin and family data.MethodsA total of 1126 Korean male adult twins and family members from the Healthy Twin Study with serum 25(OH)D measurement were included in this cross-sectional study. Intraclass correlation coefficients (ICCs) and heritability were calculated by mixed linear regression analysis and quantitative genetic analysis after adjusting for environmental and lifestyle factors.ResultsMean (± standard deviation; SD) of serum 25(OH)D concentration was 15.34 ± 6.18 ng/ml. The prevalence of vitamin D insufficiency was 19.8% and that of vitamin D deficiency was 77.9%. After adjusting for age, the highest ICC (0.61) was observed for monozygotic twin pairs while the lowest ICC (0.31) was found for father-son pairs. Age-adjusted heritability was estimated to be 58%. When physical activity, multivitamin intake and season of blood sampling were further considered, the ICC and heritability did not materially change. In the sensitivity analysis after excluding known multivitamin users, age-adjusted heritability was reduced to 44%.ConclusionsIn our study of Korean male twins and family members, heritability of 25(OH)D was moderately high. This supports the finding that genetic factors have significant influence on vitamin D status.

Epicardial Fat Thickness and Bone Mineral Content: The Healthy Twin Study in Korea.

BackgroundThe conventional concept of positive association between general obesity and bone health was challenged in recent studies reporting the different effects of specific fat deposition on bone health. In the present study, we investigated the association between epicardial fat and bone health.MethodsWe measured echocardiographic epicardial fat thickness (EFT) and bone mineral content (BMC) in a twin-family cohort of Koreans (n = 1,198; 525 men, 460 pre- and 213 post-menopausal women). A total 121 pairs of monozygotic twin (MZ) and 404 pairs of dizygotic twin and sibling pairs (DZ/Sib) were included.ResultsEFT was positively associated with BMC in total, as well as in three subgroups (β = 0.107, 0.076, and 0.058 for men, pre-, and post-menopausal women, respectively). The positive association between EFT and BMC remained for DZ/Sib difference analysis, but was absent for MZ comparisons. The positive association between BMI and BMC was consistent for DZ/Sib and MZ difference analysis. After adjusting for the effect of general obesity via BMI, the association between BMC and EFT was statistically non-significant (β = 0.020, 0.000, and −0.009 for men, pre-, and post-menopausal women, respectively).ConclusionOur findings do not support epicardial fat’s beneficial effects on bone health, whereas general adiposity has an osteotropic effect. The association between EFT and BMC is through common genetic component factors.

Association Between Excessive Alcohol Consumption and Echocardiographic Parameters According to the Presence of Flushing Reaction in Korean Men: A Community-Based Study.

The objective of this study was to investigate the effect of excessive alcohol consumption on heart reflected by various echocardiographic parameters according to the presence or absence of flushing reaction that might reflect acetaldehyde metabolism. A total of 854 Korean men without significant cardiovascular diseases who underwent echocardiography and participated in the Korean Healthy Twin Study were used as subjects of this study. These subjects were classified into 3 categories: nondrinker, moderate drinker (≤196g/wk), and heavy drinker (>196g/wk) within 2 strata of flushing reaction to alcohol drinking. Association between echocardiographic measurements and categories of the amount of alcohol consumption considering flushing reaction were evaluated using mixed linear regression model. The proportion of flushers among drinkers was 39.5% (278 of 703). In stratified analysis by flushing reaction, nonflushers showed significantly higher left ventricular mass index (β: 4.605; 95% CI: 0.966, 8.243) and significantly lower ratio of peak early diastolic velocities (E peak) over peak late diastolic velocities of mitral inflow (β: -0.103; 95% CI: -0.198, -0.008) in heavy drinkers compared to nondrinkers. Flushers showed significantly higher left atrial (LA) volume index (β: 2.712; 95% CI: 0.456, 4.968) in heavy drinkers and significantly lower ratio of E peak over the peak early diastolic mitral annular velocities (β: -0.493; 95% CI: -0.902, -0.085) in moderate drinkers compared to nondrinkers. However, the interaction according to flushing reaction was only statistically significant for the association between alcohol consumption and LA volume index (p for interaction=0.004). Alcohol consumption is associated with changes in cardiac structure and function. Such association might be influenced by acetaldehyde metabolism.

Neural mechanism and heritability of complex motor sequence and audiovisual integration: A healthy twin study.

Complex motor sequencing and sensory integration are two key items in scales assessing neurological soft signs. However, the underlying neural mechanism and heritability of these two functions is not known. Using a healthy twin design, we adopted two functional brain imaging tasks focusing on fist-edge-palm (FEP) complex motor sequence and audiovisual integration (AVI). Fifty-six monozygotic twins and 56 dizygotic twins were recruited in this study. The pre- and postcentral, temporal and parietal gyri, the supplementary motor area, and the cerebellum were activated during the FEP motor sequence, whereas the precentral, temporal, and fusiform gyri, the thalamus, and the caudate were activated during AVI. Activation in the supplementary motor area during FEP motor sequence and activation in the precentral gyrus and the thalamic nuclei during AVI exhibited significant heritability estimates, ranging from 0.5 to 0.62. These results suggest that activation in cortical motor areas, the thalamus and the cerebellum associated with complex motor sequencing and audiovisual integration function may be heritable.

Heritability of the morphology of optic nerve head and surrounding structures: The Healthy Twin Study.

BackgroundOptic nerve head (ONH) and surrounding structures such as β-zone peripapillary atrophy (PPA) are important structures in glaucomatous pathogenesis. Thus, for understanding genetic components in glaucoma pathogenesis, it is necessary to evaluate the heritability of ONH and surrounding structures. The present study investigated the genetic influences on ONH and surrounding structures such as β-zone PPA and retinal vessels.MethodsA total of 1,205 adult twins and their family members (362 monozygotic (MZ) twin subjects (181 pairs), 64 dizygotic (DZ) twin subjects (32 pairs), and 779 singletons from 261 families), were part of the Korean Healthy Twin Study. ONH parameters including the vertical cup-to-disc ratio, the presence, the area and the location of β-zone PPA and the angular location of retinal vein were measured. The genetic influences on the structures were evaluated using variance-component methods.ResultsThe intraclass correlation coefficient (ICC) values of axial length were highest among the parameters. The ICCs of the area and location of PPA were similar to those of vertical cup-to-disc ratio. However, retinal vessel angular locations showed low ICC values even in MZ twins. After age and sex adjustment, for axial length, vertical cup-to-disc ratio, the presence, area and location of PPA, the estimated narrow-sense heritability was 0.85, 0.48, 0.76, 0.50 and 0.65 in the right eye and 0.84, 0.47, 0.72, 0.46 and 0.72 in the left eye, respectively. The estimated narrow-sense heritability of angular location of the superior and inferior vein was 0.17 and 0.12 in the right eye and 0.13 and 0.05 in the left eye, respectively.ConclusionsONH and surrounding structures such as vertical cup-to-disc ratio and the presence, the area and the location of β-zone PPA seemed to be determined by the substantial genetic influence, whereas the venous angular location did not.

Cross-sectional association between testosterone, sex hormone-binding globulin and metabolic syndrome: The Healthy Twin Study.

This study evaluated an association between testosterone, sex hormone-binding globulin (SHBG) and metabolic syndrome (MetS).We also evaluated the genetic and environmental influences on the association. Cross-sectional. Community-based study. A total of 1098 Korean adult men including 139 monozygotic twin pairs. MetS was defined using the National Cholesterol Education Program-Third Adult Treatment Panel (NCEP ATP III) and International Diabetes Federation (IDF) criteria. The associations between MetS and sex hormones were evaluated using linear mixed model and generalized estimating equation model. After considering covariates such as smoking, alcohol consumption and physical exercises as well as SHBG or testosterone, the risk of MetS defined by NCEP ATP III criteria decreased by 31%, 29%, and 48%, respectively, with 1-standard deviation increase in total testosterone (TT), free testosterone (cFT) and SHBG. Similar findings were revealed with IDF criteria. Metabolic component specific analysis showed that sex hormones were inversely associated with several components of MetS: TT with abdominal obesity, low high-density lipoprotein cholesterol (HDL-C) and high blood pressure; cFT with abdominal obesity and high blood pressure; SHBG with all components except high blood pressure. Cotwin control analysis found an inverse correlation between within-pair differences in testosterone and SHBG levels and within-pair differences in waist circumference only. Both testosterone and SHBG were inversely associated with MetS although the inverse associations with the sex hormones were not consistently found across individual metabolic components. Findings from cotwin analysis suggest a significant contribution of unshared unique environmental effect to the association between testosterone and SHBG and abdominal obesity.

Associations Between Adiposity and Metabolic Syndrome Over Time: The Healthy Twin Study.

We evaluated the association between changes in adiposity traits including anthropometric and fat mass indicators and changes in metabolic syndrome traits including metabolic syndrome clustering and individual components over time. We also assessed the shared genetic and environmental correlations between the two traits. Participants were 284 South Korean twin individuals and 279 nontwin family members had complete data for changes in adiposity traits and metabolic syndrome traits of the Healthy Twin study. Mixed linear model and bivariate variance-component analysis were applied. Over a period of 3.1 ± 0.6 years of study, changes in adiposity traits [body mass index (BMI), waist circumference, total fat mass, and fat mass to lean mass ratio] had significant associations with changes in metabolic syndrome clustering [high blood pressure, high serum glucose, high triglycerides (TG), and low high-density lipoprotein cholesterol] after adjusting for intra-familial and sibling correlations, age, sex, baseline metabolic syndrome clustering, and socioeconomic factors and health behaviors at follow-up. Change in BMI associated significantly with changes in individual metabolic syndrome components compared to other adiposity traits. Change in metabolic syndrome component TG was a better predictor of changes in adiposity traits compared to changes in other metabolic components. These associations were explained by significant environmental correlations but not by genetic correlations. Changes in anthropometric and fat mass indicators were positively associated with changes in metabolic syndrome clustering and those associations appeared to be regulated by environmental influences.

Relationships Between Self-awareness and Clinical Diagnostic Findings of Abnormal Foot Arch Height in Koreans.

ObjectiveTo see how people think about their own feet, and evaluate whether there are correlations among self-awareness of the participants and clinical examination findings.MethodsAdult twins and their families who participated in the Healthy Twin study from May 2008 to April 2010 were recruited. Participants were asked whether they thought their feet were normal, flat, or cavus. The lateral talometatarsal angles were measured on foot X-rays to determine the foot arch height. Using the podoscopic footprints taken with the podobaroscope, the Staheli arch index was also measured. Kappa statistics were used to calculate degree of agreement among the three measurement methods.ResultsSelf-awareness and radiographic findings were significantly different (Pearson chi-square test, p=0.000) and only slightly agreed (kappa measure of agreement=0.136, p=0.000). Self-awareness and podoscopy results revealed a significant difference (Pearson chi-square test, p=0.000), with only slight agreement (kappa measure of agreement=0.072, p=0.000).ConclusionThere is significant disagreement between patients' perception of their feet and actual test results. Many people may have an incorrect assumption about their own foot conditions that may be reflected in improper management. Dissemination of accurate information about foot disorders by foot clinicians would be helpful.

Association between Lumbar Bone Mineral Density and Carotid Intima-Media Thickness in Korean Adults: a Cross-sectional Study of Healthy Twin Study.

Bone mineral density (BMD) has been suggested to be associated with atherosclerosis. In the present study, we evaluated the association between lumbar BMD and the segments of carotid intima-media thickness (CIMT), a surrogate marker of subclinical atherosclerosis, in Korean adults, with consideration of sex and menopause status. Among 1,679 Korean adults who enrolled in a Healthy Twin Study, 723 men, 690 premenopausal women, and 266 postmenopausal women measured the CIMT at the common carotid artery intima-media thickness (CCA-IMT), carotid bifurcation intima-media thickness (BIF-IMT), internal carotid artery intima-media thickness (ICA-IMT) using B-mode ultrasound and lumbar BMD using dual-energy X-ray absorptiometry. The composite CIMT was calculated as the mean value of three CIMTs. The association was evaluated using linear mixed models. In premenopausal women, lumbar BMD was positively associated with composite CIMT and with CCA-IMT (P = 0.008 and 0.002, respectively). However, no association was observed between BMD and CIMT in men or in postmenopausal women. Stratified analysis revealed the effect of body mass index (BMI) on the association between BMD and CIME. The positive association in premenopausal women persisted only in low BMI (< 25 kg/m2) group, whereas a positive association appeared at high BMI (≥ 25 kg/m2) group in men. A high lumbar BMD may indicate an elevated risk of subclinical atherosclerosis in premenopausal women and men with high BMI.