Fat mass index and airway hyperresponsiveness in Korean adults.

OBJECTIVE: Airway hyperresponsiveness (AHR) is associated with asthma and obesity, which is defined as a high body mass index. Body mass mainly comprises fat mass (FM) and muscle mass (MM), which are independent of each other. We investigated the effect of changes in FM over time on the development of asymptomatic AHR in adults. METHODS: This long-term longitudinal study included adults who were underwent health checkups at the Seoul National University Hospital Gangnam Center. The participants underwent two methacholine bronchial provocation tests with a follow-up period (between the first and second tests) of more than 3 years and bioelectrical impedance analysis (BIA) at all visits. FM index (FMI; FM normalized for height) and MM index (MMI; MM normalized for height) were calculated using BIA. RESULTS: The study included 328 adult participants (61 women and 267 men). The mean number of BIA measurements was 6.96 and the follow-up duration was 6.69 years. In total, 13 participants showed a positive conversion of AHR. Multivariate analysis indicated that a high rate of change in FMI ([g/m2]/year), not MMI, was significantly associated with the risk of AHR development (P = 0.037) after adjustment for age, sex, smoking status, and FEV1 predicted. CONCLUSION: A rapid gain of FM over time may be a risk factor for developing AHR in adults. Prospective studies are needed to confirm our results and evaluate the role of FM reduction in preventing AHR development in obese adults.

Chronic viral hepatitis accelerates lung function decline in smokers.

Although hepatitis B virus (HBV) and hepatitis C virus (HCV) are hepatotrophic viruses, they may affect pulmonary diseases. The purpose of this study was to assess whether chronic viral hepatitis (CVH) infection was associated with a rapid decline in lung function. Repeated measurements of lung function were obtained from a well-curated health check-up database. A case was defined as an individual positive for HBsAg or anti-HCV antibody. A control was randomly selected (from the same dataset) after 1:1 matching in terms of age, sex, height, the body mass index, and smoking status. Separate analyses of non-smokers and smokers were performed. A total of 701 cases were enrolled (586 with HBV and 115 with HCV). In cross-sectional analysis, both forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) decreased significantly only in smokers (smoking cases vs. smoking controls) (adjusted p = 6.6 × 10-5 and adjusted p = 2.2 × 10-3, respectively). In longitudinal analysis, smoking cases showed significantly greater FEV1 and FVC decline rates than did smoking controls (adjusted p = 8.5 × 10-3 and adjusted p = 1.2 × 10-5, respectively). Such associations were particularly high in smoking cases at intermediate-to-high risk of hepatic fibrosis, as evaluated by the non-invasive Fibrosis-4 index. In summary, CVH was associated with both decreased lung function and accelerated lung function decline in smokers. A non-invasive measurement of hepatic fibrosis may be useful in predicting rapid lung function decline in smokers with CVH.

Relationships between lung function decline and skeletal muscle and fat mass changes: a longitudinal study in healthy individuals.

BACKGROUND: The associations between long-term changes in body mass composition and decline in lung function in healthy adults are unknown. METHODS: Using a well-defined health check-up database, we first assessed individual longitudinal changes in muscle mass (MM) and fat mass (FM) measured via bioelectrical impedance analyses. Then we classified the enrolled individuals into five body composition groups according to their MM index (MMI) [MM (kg)/height (m)2 ] or FM index (FMI) [FM (kg)/height (m)2 ] change rate quartiles. Linear mixed models adjusted for age, smoking status, height, and body mass index were used to analyse the rate of forced expiratory volume in 1 s (FEV1) decline and body composition groups. RESULTS: A total of 15 476 middle-aged individuals (6088 women [mean age ± standard deviation: 50.74 ± 7.44] and 9388 men [mean age ± standard deviation: 49.36 ± 6.99]) were enrolled. The mean number of measurements was 6.96 (interquartile range [IQR]: 5-9) over an average follow-up period of 8.95 years (IQR: 6.73-11.10). Decrease in MMI was significantly associated with accelerated FEV1 decline in men only (P = 1.7 × 10-9 ), while increase in FMI was significantly associated with accelerated FEV1 decline in both women and men (P = 7.9 × 10-10 and P < 2.0 × 10-16 respectively). Linear mixed model analyses indicated that annual increase of 0.1 kg/m2 in MMI was related to accelerated FEV1 decline by 30.79 mL/year (95% confidence interval [CI]: 26.10 to 35.48 mL/year) in men. Annual increase of 0.1 kg/m2 in FMI was related to accelerated FEV1 decline by 59.65 mL/year in men (95% CI: 56.84 to 62.28 mL/year) and by 22.84 mL/year in women (95% CI: 18.95 to 26.74 mL/year). In body composition analysis, we found increase in MMI was significantly associated with attenuated FEV1 decline in men only (P = 1.7 × 10-9 ), while increase in FMI was significantly associated with accelerated FEV1 decline in both women and men (P = 7.9 × 10-10 and P < 2.0 × 10-16 respectively). Individuals characterized with gain MM combined with loss of FM were associated with the most favourable outcome (i.e. the smallest rate of decline in FEV1) in both women and men. In men, loss of FM over time is more closely related with attenuated FEV1 decline than change in MM (gain or loss). CONCLUSIONS: Change in body composition over time can be used to identify healthy middle-aged individuals at high risk for rapid FEV1 decline.

Lung function decline is associated with serum uric acid in Korean health screening individuals.

We performed a retrospective cohort study of 19,237 individuals who underwent at least three health screenings with follow-up periods of over 5 years to find a routinely checked serum marker that predicts lung function decline. Using linear regression models to analyze associations between the rate of decline in the forced expiratory volume in 1 s (FEV1) and the level of 10 serum markers (calcium, phosphorus, uric acid, total cholesterol, total protein, total bilirubin, alkaline phosphatase, aspartate aminotransferase, creatinine, and C-reactive protein) measured at two different times (at the first and third health screenings), we found that an increased uric acid level was significantly associated with an accelerated FEV1 decline (P = 0.0014 and P = 0.037, respectively) and reduced FEV1 predicted % (P = 0.0074 and P = 8.64 × 10-7, respectively) at both visits only in non-smoking individuals. In addition, we confirmed that accelerated forced vital capacity (FVC) and FEV1/FVC ratio declines were observed in non-smoking individuals with increased serum uric acid levels using linear mixed models. The serum uric acid level thus potentially predicts an acceleration in lung function decline in a non-smoking general population.

Vitamin D deficiency and lung function decline in healthy individuals: A large longitudinal observation study.

AIM: A reliable evidence from a comprehensive large-scale study supporting associations between serum vitamin D (25-hydroxyvitamin D) level (SVDL) and lung function decline (LFD) in healthy individuals has been unavailable. Using a well-established health screening database, we assessed the associations between SVDL and LFDs, measured as the forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1) and FEV1/FVC ratio. METHODS: Serial SVDL and lung function data were analyzed using linear mixed models, which were performed in smokers and non-smokers, separately. Vitamin D-deficient individuals (VDDs) were defined when their SVDLs were consistently lower than 20 ng/mL at all measurements. RESULTS: A total of 1371 individuals were analyzed. The mean FEV1 decline rates of VDDs and vitamin D-normal individuals (VDNs) in smokers were -33.35 mL/year (95% CI: 39.44 to -27.26 mL/year) and -15.61 mL/year (95% CI: 27.29 to -4.21 mL/year) respectively, over a mean of 6.29 years of observation with statistical significance (P < 0.001). However, there was no significant differences observed between decline rates of FEV1 in non-smokers. Similarly, FVC decline rates of VDDs were significantly greater than those of VDNs only in smokers (P < 0.001). However, FEV1/FVC ratio decline rates showed no significant difference between VDDs and VDNs regardless of their smoking status. CONCLUSIONS: Consistently low SVDLs predicted more rapid FEV1 and FVC declines in smokers. However, FEV1/FVC decline rate was not associated with SVDL. SVDL may be used to identify healthy smoking individuals at high risk for accelerated LFD.

Blood Eosinophil Count as a Predictor of Lung Function Decline in Healthy Individuals.

BACKGROUND: Little is known about the effect of blood eosinophil count (BEC) on a decline in lung function in healthy individuals. OBJECTIVE: Using a well-established health screening database, we assessed the associations between BEC and a decline in lung function, measured as the forced expiratory volume in 1 second (FEV1). METHODS: Serial BEC and FEV1 data were analyzed using linear mixed models adjusted for gender, height, and smoking status. The association between BEC consistency and a decline in FEV1 was evaluated in subpopulation analyses. RESULTS: A total of 4634 individuals were enrolled. The mean number of health screenings was 7.49 over an average of 11.74 years of observation. A higher log2-transformed BEC was significantly associated with a greater decline in FEV1 that was stronger in nonsmokers (P = 8.56 × 10-8) than in smokers (P = 1.52 × 10-3). In subpopulation analyses of 2018 individuals with consistent BECs, those with BECs consistently ≥100/µL (P = 4.58 × 10-6), ≥200/µL (P = 3.53 × 10-7), and ≥300/µL (P = 1.12 × 10-3) had a significantly higher dose-dependent FEV1 decline than those with BECs consistently <100/µL. A BEC threshold of 100/µL in nonsmokers and 200/µL in smokers may predict an accelerated decline in FEV1. CONCLUSIONS: BEC is associated with a decline in FEV1, and a consistently high BEC is an independent risk factor for an accelerated decline in FEV1. These results suggest the use of the BEC to identify healthy individuals at high risk for developing chronic lung disease, which in turn may enable a tailored preventive strategy.

Multifaceted interventions to reduce acute exacerbations in elderly asthmatics.

BACKGROUND: Although many risk factors are known to be associated with poor asthma outcomes in the elderly, the literature on the effect of risk factor control on asthma outcomes in the elderly is very sparse. OBJECTIVE: To evaluate the role of multifaceted interventions in reducing acute exacerbations in elderly asthmatics. METHODS: A total of 100 subjects were randomly selected from our prospective cohort of elderly asthmatics aged 65 years or older and were provided multifaceted intervention for 1 year. Our multifaceted interventions included repeated education on asthma and inhaler technique for patients and their caregivers, provision of an action plan to cope with acute exacerbations, short message service to prevent follow-up losses, and oral replacement of magnesium. The primary outcome was an acute asthma exacerbation rate compared to the previous year. RESULTS: Ninety-two subjects completed this study, although only 58 subjects continued to take magnesium. Compared to the previous year, the acute asthma exacerbation rate showed a significant reduction from 67% to 50% (p = 0001) and significant improvement was observed in forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) (p = 0.04, p = 0.036 for each). Interestingly, a subgroup analysis revealed that predicted value of FEV1 increased significantly in subjects who continued to take magnesium from 79.6% to 87.1% (p = 0.008). CONCLUSION: To reduce acute exacerbations in elderly asthmatics, a multifaceted approach in increase medical awareness, proficiency and adherence to inhaler, assistance of caregivers and correction of micronutrients deficiency is likely to be effective. In addition, a continuous oral replacement of magnesium may increase FEV1 in elderly asthmatics.

Diagnostic accuracy of fractional exhaled nitric oxide measurement in predicting cough-variant asthma and eosinophilic bronchitis in adults with chronic cough: A systematic review and meta-analysis.

BACKGROUND: Individual studies have suggested the utility of fractional exhaled nitric oxide (Feno) measurement in detecting cough-variant asthma (CVA) and eosinophilic bronchitis (EB) in patients with chronic cough. OBJECTIVE: We sought to obtain summary estimates of diagnostic test accuracy of Feno measurement in predicting CVA, EB, or both in adults with chronic cough. METHODS: Electronic databases were searched for studies published until January 2016, without language restriction. Cross-sectional studies that reported the diagnostic accuracy of Feno measurement for detecting CVA or EB were included. Risk of bias was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. Random effects meta-analyses were performed to obtain summary estimates of the diagnostic accuracy of Feno measurement. RESULTS: A total of 15 studies involving 2187 adults with chronic cough were identified. Feno measurement had a moderate diagnostic accuracy in predicting CVA in patients with chronic cough, showing the summary area under the curve to be 0.87 (95% CI, 0.83-0.89). Specificity was higher and more consistent than sensitivity (0.85 [95% CI, 0.81-0.88] and 0.72 [95% CI, 0.61-0.81], respectively). However, in the nonasthmatic population with chronic cough, the diagnostic accuracy to predict EB was found to be relatively lower (summary area under the curve, 0.81 [95% CI, 0.77-0.84]), and specificity was inconsistent. CONCLUSIONS: The present meta-analyses indicated the diagnostic potential of Feno measurement as a rule-in test for detecting CVA in adult patients with chronic cough. However, Feno measurement may not be useful to predict EB in nonasthmatic subjects with chronic cough. These findings warrant further studies to validate the roles of Feno measurement in clinical practice of patients with chronic cough.

The efficacy of single premedication with antihistamines for radiocontrast media hypersensitivity.

BACKGROUND: Single premedication with antihistamines for radiocontrast media (RCM) hypersensitivity is frequently used in real world at the emergent situation although its efficacy is not proven. OBJECTIVE: To evaluate the effect of intravenous antihistamines as a premedication in general population who had experience of mild adverse reactions to iodinated RCM. METHODS: A retrospective observational study on 14,785 subjects who had RCM-enhanced computed tomography scans between January 2014 and December 2015 in Seoul National University Hospital Gangnam Healthcare Center, Seoul, South Korea. RESULTS: Among 453 subjects who had a history of mild RCM-induced hypersensitivity reactions, 273 subjects had a single premedication of intravenous antihistamine. When comparing antihistamine-premedication group and nonpremedication group, there is no protective effect of antihistamines on the incidence rate and severity of hypersensitivity (10.6% vs. 11.7%, p = 0.729). CONCLUSION: The clinical efficacy of a single premedication of antihistamines for mild RCM-induced hypersensitivity was not confirmed.

Validation of the Korean version of the European Community Respiratory Health Survey screening questionnaire for use in epidemiologic studies for adult asthma.

BACKGROUND: Standardized questionnaire is one of key instruments for general population surveys. OBJECTIVE: The present study aimed to develop and validate the Korean version of the European Community Respiratory Health Survey (ECRHS) screening questionnaire for adult asthma surveys. METHODS: The ECRHS screening questionnaire was translated into Korean language according to the international criteria. Study participants were prospectively recruited from six referral hospitals and one health check-up center. Comprehensibility of the translation was tested in a pilot study of 10 patients. The reliability was evaluated by internal consistency and test-retest repeatability. Validity was assess with regard to physician-diagnosed asthma. RESULTS: A total of 100 adult asthma patients and 134 volunteers were recruited. Reliability was examined for 10 items in 100 asthmatics; Cronbach α coefficients were 0.84, and test-retest repeatability was good (Cohen κ coefficient, 0.71-1.00). Validity was assessed for 8 items in 234 participants; in particular, 'recent wheeze' showed a high sensitivity (0.89) for physician-diagnosed asthma. 'Recent asthma attack' and 'current asthma medication' showed high specificity (0.96-0.98). CONCLUSION: The present study demonstrated that the Korean version of the ECRHS screening questionnaire was comprehensible, reliable and valid. We suggest the questionnaire to be utilized in further epidemiological studies for asthma in Korean adult populations.

Influence of chronic sinusitis and nasal polyp on the lower airway of subjects without lower airway diseases.

PURPOSE: Upper and lower respiratory tract pathologies are believed to be interrelated; however, the impact of upper airway inflammation on lung function in subjects without lung disease has not been evaluated. This study investigated the association of CT finding suggesting chronic sinusitis and lung function in healthy subjects without lung disease. METHODS: This was a retrospective study of prospectively collected data from 284 subjects who underwent a pulmonary function test, bronchial provocation test, rhinoscopy, and osteomeatal unit computed tomography offered as a private health check-up option. RESULTS: CT findings showed that the sinusitis group had a significantly lower FEV1/FVC ratio than subjects without sinusitis finding (78.62% vs 84.19%, P=0.019). Among the sinusitis group, subjects classified by CT findings as the extensive disease group had a slightly lower FEV1/FVC than those of the limited disease group (76.6% vs 79.5%, P=0.014) and the associations were independent of the presence of airway hyperresponsiveness. The subjects with nasal polyp had also lower FEV1 and FEV1/FVC than subjects without nasal polyp (FEV1: 100.0% vs 103.6%, P=0.045, FEV1/FVC: 77.4% vs 80.0%, P=0.005). CONCLUSIONS: CT findings suggesting chronic sinusitis and nasal polyp were associated with subclinical lower airway flow limitation even in the absence of underlying lung disease.

Association of insulin resistance with bronchial hyperreactivity.

BACKGROUND: Several epidemiologic studies showed the significant association of insulin resistance with asthma. OBJECTIVE: The aim of this study was to evaluate the association of insulin resistance with airway hyperresponsiveness (AHR) in adult population. METHODS: 1,058 subjects who visited to the Seoul National University Hospital Gangnam Center from October 2007 to January 2009 for a routine health check-up were enrolled. All subjects completed a questionnaire, anthropometric measurements such as body mass index (BMI) and waist circumference, blood tests, pulmonary function test, and methacholine bronchial provocation test (MBPT). Insulin resistance was estimated from the homeostasis model of assessment of insulin resistance (HOMA-IR). RESULTS: Thirty-three subjects (3.1%) had AHR based on MBPT. The subjects with AHR had higher BMI, waist circumference, and HOMA-IR than those without AHR (p < 0.001, p = 0.003, and p = 0.002, respectively). In case of men, fasting insulin level and HOMA-IR had significant correlation with forced expiratory volume in 1 second (%) (r = -0.1440, p = 0.011, and r = -0.1156, p = 0.042, respectively). Fasting insulin level and HOMA-IR were higher in men with AHR than in those without (p = 0.046 and p = 0.040, respectively). In binary logistic regression analysis after adjustment for age, HOMA-IR was the significant risk factor for AHR in men (HOMA-IR: odds ratio [OR], 3.21; 95% confidence interval [CI], 1.00-10.30). In case of women, fasting insulin, glucose level, or insulin resistance had no significant correlation with lung function. BMI, waist circumference, and HOMA-IR were significantly higher in women with AHR than in those without (p = 0.001, p = 0.011, and p = 0.010, respectively). In binary logistic regression analysis after adjustment for age, BMI and HOMA-IR were the significant risk factors for AHR in women (BMI: OR, 2.20; 95% CI, 1.23-3.82; insulin resistance: OR, 1.05; 95% CI, 1.00-1.09). CONCLUSION: Insulin resistance was significantly associated with bronchial hyperreactivity, which is the most characteristic feature of asthma.

Are asthmatic patients prone to bone loss?

BACKGROUND: Recent studies suggest an association between allergic diseases, including asthma, and lower vitamin D level, a well-known risk factor of osteoporosis. However, it is not yet clearly known whether patients with asthma are prone to bone loss. OBJECTIVE: To evaluate whether the occurrence of airway hyperresponsiveness (AHR) or asthma is related to significant changes in bone mineral density (BMD). METHODS: We retrospectively enrolled 7,034 patients who had undergone a health checkup program, including BMD tests and methacholine bronchial challenge tests, at the Seoul National University Hospital, Healthcare System Gangnam Center, from November 1, 2004 to April 30, 2011. Asthma was ascertained by self-reported medical diagnosis by a physician. Patients with a history of systemic corticosteroid medication use were excluded from the study. RESULTS: Among a total of 7,034 patients, 216 (3.1%) had a positive AHR test result, and 217 (3.1%) had a history of asthma. Lumbar spine and femur BMD of patients with AHR were significantly lower than those without AHR (-0.53 ± 1.50 vs -0.03 ± 1.49, -0.47 ± 0.97 vs -0.22 ± 0.99, respectively; P < .001 for both). After being adjusted for age, sex, body mass index, smoking status, postmenopausal state, and previous history of hormone replacement therapy, the proportion of patients with osteopenia or osteoporosis was much higher in the AHR-positive group than in the AHR-negative group (odds ratio, 1.715; 95% confidence interval, 1.252-2.349) and in the ever-asthma group than in the never-asthma group (odds ratio, 1.526; 95% confidence interval, 1.120-2.079). CONCLUSION: In the current study, AHR and asthma were related to clinically meaningful BMD decrease, although the causal relationship is unclear.

Influence of the Adjuvants and Genetic Background on the Asthma Model Using Recombinant Der f 2 in Mice.

Der f 2 is the group 2 major allergen of a house dust mite (Dermatophagoides farinae) and its function has been recently suggested. To determine the optimal condition of sensitization to recombinant Der f 2 (rDer f 2) in murine model of asthma, we compared the effectiveness with different adjuvants in BALB/c and C57BL/6 mice. Mice from both strains sensitized with rDer f 2 by intraperitoneal injection or subcutaneous injection on days 1 and 14. The dosage was 20 µg. Freund's adjuvants with pertussis toxin (FP) or alum alone were used as adjuvants. On days 28, 29, and 30, mice were challenged intranasally with 0.1% rDer f 2. We evaluated airway hyperresponsivenss, eosinophil proportion in lung lavage, airway inflammation, and serum allergen specific antibody responses. Naive mice were used as controls. Airway hyperresponsiveness was increased in C57BL/6 with FP, and BALB/c with alum (PC200: 13.5±6.3, 13.2±6.7 vs. >50 mg/ml, p<0.05). The eosinophil proportion was increased in all groups; C57BL/6 with FP, BALB/c with FP, C57BL/6 with alum, BALB/c with alum (24.8±3.6, 20.3±10.3, 11.0±6.9, 5.7±2.8, vs. 0.0±0.0%, p<0.05). The serum allergen specific IgE levels were increased in C57BL/6 with FP or alum (OD: 0.8±1.4, 1.1±0.8, vs. 0.0±0.0). C57BL/6 mice were better responders to rDer f 2 and as for adjuvants, Freund's adjuvant with pertussis toxin was better.

Clinical characteristics and long-term outcomes related to sputum eosinophilia in Korean asthmatics.

BACKGROUND: Bronchial asthma is usually associated with high sputum eosinophil levels. However, recent reports have suggested the importance of noneosinophilic asthma (NEA) as a distinct phenotype of asthma. OBJECTIVE: The aim of this study was to evaluate clinical significance of sputum eosinophilia and long-term treatment outcomes related to sputum eosinophilia in Korean asthmatics. METHODS: A total of 201 steroid-naive asthmatics who had undergone induced sputum analysis at baseline were selected from the Cohort for Reality and Evolution of Adult Asthma study population. Clinical evaluation, spirometry, a skin-prick test, a methacholine bronchial provocation test, and sputum eosinophil analysis were performed initially, and patients received the treatment recommended by the Global Initiative for Asthma. Lung function was evaluated every 6 months, and 53 patients completed 24 months of regular follow-up visits. Sputum eosinophilia was defined as a sputum eosinophil count of >3%. RESULTS: Of the 201 steroid-naive asthmatics, 97 patients had NEA and 104 had eosinophilic asthma (EA). Only 52% of steroid-naive asthmatic subjects had elevated baseline sputum eosinophil levels. A higher percentage of sputum eosinophils was associated with a lower PC20 (r = -0.193; p = 0.009, Spearman correlation), but not with forced expiratory volume in one second (FEV1) (r = 0.045; p = 0.525). During the 24-month study period, the percentage change of FEV1 was significantly lower in the NEA group than in the EA group at 6, 12, 18, and 24 months (p < 0.05). The NEA group, unlike the EA group, showed no significant improvement in FEV1 at 6, 12, 18, or 24 months (p > 0.05). CONCLUSION: A higher sputum eosinophil percentage was correlated with a higher airway hyperresponsiveness. Compared with EA patients, NEA patients had poor treatment outcomes in the 2-year follow-up of a Korean asthma cohort population.

Effects of resistance training and aerobic exercise on insulin sensitivity in overweight korean adolescents: a controlled randomized trial.

BACKGROUND: Data on the impact of resistance training on insulin resistance in overweight or obese children are inconclusive. METHODS: Thirty overweight South Korean adolescents (mean age of 13.10 years) were divided by sex, and then randomly assigned to one of three treatment groups, which were the diet only (DO), diet with aerobic exercise (AE), or diet with resistance training (RT) group. Physiologic and metabolic parameters were assessed at baseline and after 12 weeks of exercise training and diet modification. RESULTS: Both exercise groups (aerobic and resistance) showed significant improvements in their insulin area under the curve and insulin sensitivity index values when compared to their baseline values while the DO group showed no significant changes in these variables. Age-, sex-, and body mass index (BMI)-adjusted intergroup comparison analyses showed a marked reduction in BMI and a significant reduction in muscle mass in the AE group when compared to the RT group and the DO group, respectively. CONCLUSION: A 12-week exercise training program of either resistance or aerobic activity improved insulin sensitivity in overweight adolescents, although it failed to show superiority over a DO program. Aerobic exercise decreased both body weight and BMI, and it was noted that this group also had a significant reduction in muscle mass when compared to the DO group.

Association between subcutaneous abdominal fat and airway hyperresponsiveness.

Epidemiological studies have shown that obesity is significantly associated with airway hyperresponsiveness (AHR). The aim of this study was to determine the effect of abdominal fat distribution on the prevalence of AHR. This study was conducted on subjects who visited the Seoul National University Hospital Gangnam Center from October 2003 to January 2009. Medical records of 3205 subjects who had both a methacholine bronchial provocation test and an abdominal CT scan were retrospectively reviewed. One hundred sixty-one subjects with AHR and their 161 controls were selected for the analysis. Total, subcutaneous, and visceral abdominal fat were objectively measured by an abdominal CT scan. Both body mass index (BMI) and waist circumference were significantly associated with AHR after adjustment for smoking (BMI: OR, 1.20; 95% confidence interval [CI], 1.07-1.35; waist circumference: OR, 1.07; 95% CI, 1.02-1.11). Total and subcutaneous abdominal fat increased the risk of AHR with an OR of 1.47 (95% CI, 1.08-2.02) in the case of total abdominal fat, and an OR of 1.99 (95% CI, 1.19-3.31) in the case of subcutaneous abdominal fat. However, visceral abdominal fat was not associated with AHR. The association between subcutaneous abdominal fat and AHR was consistent, especially in men. Subcutaneous abdominal fat was significantly associated with AHR, but visceral abdominal fat was not. These results suggest a possible role for subcutaneous fat on the later development of asthma.

Outcomes of premedication for non-ionic radio-contrast media hypersensitivity reactions in Korea.

BACKGROUND: Radio-contrast media (CM)-related adverse reactions are important clinical problems that may cause fatal anaphylaxis. Accordingly, it has been common practice to premedicate patients who have had previous reactions to CM with corticosteroids, antihistamines, and H2 blockers to prevent hypersensitive reactions. However, the effectiveness of premedication has not been properly demonstrated, especially in cases related to non-ionic CM. In this study, we evaluated the effectiveness of premedication at preventing of non-ionic CM immediate-type hypersensitivity reactions. METHODS: A total of 30 patients who had been pretreated with corticosteroid and H1 antihistamines and/or H2 blockers in a 3-year period were enrolled. The results of premedication were evaluated in terms of clinical characteristics and the features of breakthrough reactions. RESULTS: Hypersensitivity reactions were not prevented in 5 of the 30 patients who had experienced prior CM reactions (overall recurrence rate after premedication 16.7%; 4/17 patients with mild previous reactions, and 1/13 patients with severe previous reactions). The recurrence rate after premedication was significantly higher in patients with mild previous reactions than in those with severe reactions (23.5% vs. 7.7%; p<0.001). The breakthrough reactions were similar to the prior reactions in terms of severity and clinical manifestations. CONCLUSION: Premedication with corticosteroid and H1 antihistamines and/or H2 blockers effectively prevent non-ionic CM-related adverse events in most patients who have had severe previous reactions to CM. However, physicians should be aware of the possibility of premedication failing and of breakthrough reactions, even in cases in which the previous reactions were mild.

Physicians' preferences for asthma guidelines implementation.

PURPOSE: Patient care based on asthma guidelines is cost-effective and leads to improved treatment outcomes. However, ineffective implementation strategies interfere with the use of these recommendations in clinical practice. This study investigated physicians' preferences for asthma guidelines, including content, supporting evidence, learning strategies, format, and placement in the clinical workplace. METHODS: We obtained information through a questionnaire survey. The questionnaire was distributed to physicians attending continuing medical education courses and sent to other physicians by airmail, e-mail, and facsimile. RESULTS: A total of 183 physicians responded (male to female ratio, 2.3:1; mean age, 40.4±9.9 years); 89.9% of respondents were internists or pediatricians, and 51.7% were primary care physicians. Physicians preferred information that described asthma medications, classified the disease according to severity and level of control, and provided methods of evaluation/treatment/monitoring and management of acute exacerbation. The most effective strategies for encouraging the use of the guidelines were through continuing medical education and discussions with colleagues. Physicians required supporting evidence in the form of randomized controlled trials and expert consensus. They preferred that the guidelines be presented as algorithms or flow charts/flow diagrams on plastic sheets, pocket cards, or in electronic medical records. CONCLUSIONS: This study identified the items of the asthma guidelines preferred by physicians in Korea. Asthma guidelines with physicians' preferences would encourage their implementation in clinical practice.

Sagittal abdominal diameter is a strong anthropometric measure of visceral adipose tissue in the Asian general population.

OBJECTIVE: Finding the anthropometric measure of visceral obesity is essential to clinical practice, because it predicts cardiovascular and metabolic risks. Sagittal abdominal diameter (SAD) has been proposed as an estimate of visceral adipose tissue (VAT). The aim of the present study was to evaluate the usefulness of SAD in predicting visceral obesity by comparing SAD to other anthropometric measures. RESEARCH DESIGN AND METHODS: Estimation of subcutaneous and visceral adipose tissue and measurement of SAD and transverse abdominal diameter using computed tomography at the umbilical level were obtained in 5,257 men and women who were enrolled in a health checkup program in Korea. To compare SAD to other anthropometric measures, linear regression analyses were used to determine correlations between anthropometrics and visceral obesity. RESULTS: SAD showed a stronger correlation to VAT than waist circumference, BMI, and transverse abdominal diameter in the both sexes (men: r = 0.804, women: r = 0.724). Waist circumference showed generally stronger associations to subcutaneous adipose tissue (SAT) than to VAT (men: r = 0.789 vs. 0.705, women: r = 0.820 vs. 0.636). Even after subdividing according to age or BMI in both sexes and analyzing multiple regressions, SAD showed the strongest correlation to VAT. CONCLUSIONS: SAD showed the strongest correlation to VAT irrespective of age, sex, and the degree of obesity compared with other anthropometric measures, whereas waist circumference may have a stronger correlation to SAT than to VAT. The clinical use of SAD has advantages over other anthropometric measures in predicting VAT.