Association between nonalcoholic fatty liver disease and left ventricular diastolic dysfunction: A 7-year retrospective cohort study of 3,380 adults using serial echocardiography

AIM

Left ventricular diastolic dysfunction (LVDD) has been observed in people with nonalcoholic fatty liver disease (NAFLD) in cross-sectional studies but the causal relationship is unclear. This study aimed to investigate the impact of NAFLD and the fibrotic progression of the disease on the development of LVDD, assessed by serial echocardiography, in a large population over a 7-year longitudinal setting.

METHODS

This retrospective cohort study included the data of 3,380 subjects from a medical health check-up program. We defined subjects having NAFLD by abdominal ultrasonography and assessed significant liver fibrosis by the aspartate transaminase (AST) to platelet ratio index (APRI), the NAFLD fibrosis score (NFS), and the fibrosis-4 (FIB-4) index. LVDD was defined using serial echocardiography. A parametric Cox proportional hazards model was used.

RESULTS

During 11,327 person-years of follow-up, there were 560 (16.0 %) incident cases of LVDD. After adjustment for multiple risk factors, subjects with NAFLD showed an increased adjusted hazard ratio (aHR) of 1.21 (95 % confidence interval [CI]=1.02-1.43) for incident LVDD compared to those without. The risk of LV diastolic dysfunction increased progressively with increasing degree of hepatic steatosis (P< 0.001). Compared to subjects without NAFLD, the multivariable-aHR (95 % CI) for LVDD in subjects with APRI < 0.5 and APRI ≥ 0.5 were 1.20 (1.01-1.42) and 1.36 (0.90-2.06), respectively (P= 0.036), while other fibrosis prediction models (NFS and FIB-4 index) showed insignificant results.

CONCLUSIONS

This study demonstrated that NAFLD was associated with an increased risk of LVDD in a large cohort. More severe forms of hepatic steatosis and/or significant liver fibrosis may increase the risk of developing LVDD.

Sustained Effectiveness and Safety of Therapeutic miR-10a/b in Alleviating Diabetes and Gastrointestinal Dysmotility without Inducing Cancer or Inflammation in Murine Liver and Colon

microRNAs (miRNAs) are key regulators of both physiological and pathophysiological mechanisms in diabetes and gastrointestinal (GI) dysmotility. Our previous studies have demonstrated the therapeutic potential of miR-10a-5p mimic and miR-10b-5p mimic (miR-10a/b mimics) in rescuing diabetes and GI dysmotility in murine models of diabetes. In this study, we elucidated the safety profile of a long-term treatment with miR-10a/b mimics in diabetic mice. Male C57BL/6 mice were fed a high-fat, high-sucrose diet (HFHSD) to induce diabetes and treated by five subcutaneous injections of miR-10a/b mimics for a 5 month period. We examined the long-term effects of the miRNA mimics on diabetes and GI dysmotility, including an assessment of potential risks for cancer and inflammation in the liver and colon using biomarkers. HFHSD-induced diabetic mice subcutaneously injected with miR-10a/b mimics on a monthly basis for 5 consecutive months exhibited a marked reduction in fasting blood glucose levels with restoration of insulin and significant weight loss, improved glucose and insulin intolerance, and restored GI transit time. In addition, the miR-10a/b mimic-treated diabetic mice showed no indication of risk for cancer development or inflammation induction in the liver, colon, and blood for 5 months post-injections. This longitudinal study demonstrates that miR-10a/b mimics, when subcutaneously administered in diabetic mice, effectively alleviate diabetes and GI dysmotility for 5 months with no discernible risk for cancer or inflammation in the liver and colon. The sustained efficacy and favorable safety profiles position miR-10a/b mimics as promising candidates in miRNA-based therapeutics for diabetes and GI dysmotility.

Erratum: Evaluation of medical nutrition therapy using the food-based index of dietary inflammatory potential (FBDI) in diabetes mellitus patients

[This corrects the article on p. 529 in vol. 17, PMID: 37266119.].

Evaluation of medical nutrition therapy using the food-based index of dietary inflammatory potential (FBDI) in diabetes mellitus patients

BACKGROUND/OBJECTIVES

Inflammation is often associated with chronic diseases, and numerous studies suggest that certain foods can modulate inflammatory status. This study aimed to assess the impact of intensive nutrition education on glycemic control and inflammation in patients with diabetes mellitus using the Korean food-based index of dietary inflammatory potential (FBDI).

SUBJECTS/METHODS

A total of 120 patients (male: 70, 58.3%) were randomly divided into two groups of 60 each, to be given intensive nutritional education (IE) and basic nutritional education (BE), respectively. As part of the nutrition education intervention, basic diabetes-related nutrition education was provided to both groups initially. In addition, the IE was provided two face-to-face nutrition education sessions based on FBDI over six months, and text transmissions were made at least eight times. We surveyed the anthropometric measurements, biochemical indicators, inflammatory markers, and dietary intake before and after the interventions. We analyzed the effects of the intensive nutrition education using the t-test, χ² test and paired t-test.

RESULTS

Of the subjects, 76.7% (46/60) of the IE and 86.7% (52/60) of the BE completed the study. The results of the paired t-test to evaluate the effectiveness of nutrition education using FBDI showed that high density lipoprotein-cholesterol increased significantly from 42.6 mg/dL before intervention to 49.2 mg/dL after intervention (P = 0.009), tumor necrosis factor-α significantly decreased from 1.25 pg/mL before intervention to 1.11 pg/mL after intervention (P =.012) in the IE. Also, glycated hemoglobin decreased from 8.0% to 7.5% in the IE but increased from 7.4% to 7.7% in the BE, and the differences between the groups were significant (P = 0.008).

CONCLUSION

These findings suggest that providing intensive FBDI-based education on anti-inflammatory foods positively affected glycemic control and inflammatory status in diabetes patients. Therefore, practical dietary plans using FBDI should be considered for diabetes patients to prevent increased inflammation.

The effectiveness of eHealth interventions on moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants: a systematic review and meta-analysis

Background

Cardiac rehabilitation is a class IA recommendation for patients with cardiovascular diseases. Physical activity is the core component and core competency of cardiac rehabilitation programs. Cardiac rehabilitation guidelines recommend patients achieve at least thirty minutes of moderate-to-vigorous intensity physical activity five or more days per week. However many patients with cardiovascular diseases are failing to meet recommended daily physical activity levels. eHealth interventions may increase moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants.

Objectives

The objective of this study was to review the evidence of the effectiveness of eHealth interventions to increase moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants. The secondary objective was to examine the effectiveness of eHealth interventions on improving exercise capacity, cardiovascular risk profile and health-related quality of life.

Methods

A comprehensive search strategy was developed for four electronic databases (PubMed, Web of Science, Embase and The Cochrane Library); through December 16, 2021. All studies reporting on eHealth interventions designed to increase moderate-to-vigorous physical activity among cardiac rehabilitation participants were included. Multiple not-blind reviewers determined study eligibility and extracted data. Risk of bias was evaluated using the Cochrane Collaboration Tool for randomized controlled trials and using the Effective Practice and Organisation of Care Cochrane Review Group for non-randomized controlled trials. Data quality using the Grading of Recommendations Assessment, Development and Evaluation professional guideline development tool. Data were pooled using a random-effects model. All statistical analyses were performed using Stata 17.

Results

Twenty-one studies were included in the review which fifteen were in the meta-analysis. The meta-analysis demonstrated eHealth interventions improved moderate-to-vigorous physical activity (standard mean difference = 0.17, 95% confidence interval: 0.07, 0.27, P&lt;0.001). No changes were observed in exercise capacity (P=0.09), cardiovascular risk profile (body mass index, P=0.19; waist circumference, P=0.7; systolic blood pressure, P=0.36; total cholesterol, P=0.72; plasma glucose, P=0.41) and health-related quality of life (P=0.12).

Conclusions

eHealth interventions are effective at increasing minutes/week of moderate-to-vigorous intensity physical activity among cardiac rehabilitation participants. Future high-quality empirical studies are needed to evaluate the effectiveness of eHealth interventions delivered, with these sub-types (wearable devices, online web portal, smart phone application, messaging services and telephone calls) delivered alone or in combination delivered more conducive to moderate-to-high intensity physical activity.

Funding Acknowledgement

Type of funding sources: None.

Delayed heart rate recovery after exercise predicts development of metabolic syndrome: A retrospective cohort study

AIMS/INTRODUCTION

Several cross-sectional studies have shown that delayed heart rate recovery (HRR) after exercise is associated with the development of metabolic syndrome (MetS). However, there has been a lack of comprehensively designed longitudinal studies. Therefore, our aim was to evaluate the longitudinal association of delayed HRR following a graded exercise treadmill test (GTX) with incident MetS.

MATERIALS AND METHODS

This was a retrospective longitudinal cohort study of participants without MetS, diabetes, or cardiovascular diseases. The HRR was calculated as the peak heart rate minus the resting heart rate after a 1 min rest (HRR1), a 2 min rest (HRR2), and a 3 min rest (HRR3). Multivariate Cox proportional hazards analysis was performed to investigate the association between HRR and development of MetS.

RESULTS

There were 676 (31.2%) incident cases of MetS identified during the follow-up period (9,683 person-years). The only statistically significant relationship was between HRR3 and the development of MetS. The hazard ratios (HRs) (95% confidence interval [CI]) of incident MetS comparing the first and second tertiles to the third tertile of HRR3 were 1.492 (1.146-1.943) and 1.277 (1.004-1.624) with P = 0.003 after adjustment for multiple risk factors. As a continuous variable, the HR (95% CI) of incident MetS associated with each one-beat decrease in HRR3 was 1.015 (1.005-1.026) with P = 0.004 after full adjustments. An HRR3 value ≤45 beats per minute (bpm) was associated with a higher risk of incident MetS compared with values >45 bpm, with an HR (95% CI) of 1.304 (1.061-1.602) and P = 0.001.

CONCLUSIONS

The slow phase of HRR, particularly HRR3, might be more sensitive at predicting the risk of MetS.

Associations between vascular risk factors and subsequent Alzheimer's disease in older adults

Background

The clinical guidelines related to the primary prevention of Alzheimer’s disease (AD) have focused on the management of vascular risk factors. However, the link between vascular risk factors and AD in older adults remains unclear. This study aimed to determine the association between vascular risk factors and subsequent AD in 178,586 older adults (age ≥ 65 years).

Methods

Participants were recruited from 2009 through 2010 and followed up for 6 years. We assessed various vascular risk factors (total cholesterol [TC], low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], triglycerides [TG], fasting glucose [FG], systolic blood pressure [SBP], diastolic blood pressure [DBP], pulse pressure [PP], and body mass index [BMI]) and their association with AD incidence, categorizing each vascular factor using current clinical guidelines.

Results

AD was observed in 6.0% of participants at follow-up. All lipid profiles (TC, LDL-C, HDL-C and TG) were positively associated with the risk of AD. SBP and PP were in negative associations with AD, and DBP was positively associated with AD. BMI exhibited a negative association with AD incidence. We found no significant association between FG and AD risk. The sex difference was observed to have effects on vascular risk factors.

Conclusions

In this study, we comprehensively investigated the association between eight vascular risk factors and the risk of incident AD. Our findings suggest that multiple vascular risk factors are related to the development of AD in older adults. These results can help inform future guidelines for reducing AD risk.

[Short-term efficacy of robotic-assisted total mesorectal excision with and without lateral lymph node dissection for mid-low advanced rectal cancer: a propensity score matching analysis]

Objective: To evaluate the feasibility, safety and efficacy of robotic-assisted lateral lymph node dissection for mid-low advanced rectal cancer. Methods: A retrospective cohort study was performed. Inclusion criteria: (1) age between 18 and 80 years old; (2) rectal adenocarcinoma diagnosed by pathology; (3) without distant metastasis by preoperative CT or MRI; (4) patients underwent robotic-assisted total mesorectal resection (TME). Exclusion criteria: (1) conversion to open surgery; (2) multiple primary tumors; (3) patients underwent combined multiple organ resection. According to the above criteria, 137 patients undergoing robotic-assisted mid-low rectal cancer resection in the First Affiliated Hospital of Xi'an Jiaotong University from December 2016 to April 2019 were enrolled. Ninety-seven cases underwent robotic-assisted total mesorectal excision (TME group) and 40 underwent robotic-assisted total mesorectal resection with lateral lymph node dissection (LLND) (TME+LLND group, pelvic LLND was performed with neurovascular guidance to retain pelvic autonomic nerves in the order of the left side the first and then the right side). The propensity score matching of 1:1 was performed with R software, based on age, sex, BMI, ASA classification, distance from tumor to the anal verge, preoperative chemoradiotherapy history, preoperative abdominal surgery history, the size of tumors and TNM stage. The operative indicators, postoperative recovery, pathology and postoperative complications within 30 days were compared between the two groups. Results: A total of 72 cases were successfully matched (36 in each group), and there were no statistically significant differences in baseline data between the two groups (all P>0.05). The operation time of TME+LLND group was significantly longer than that of TME group [275.0 (180-405) minutes vs. 220.0 (140-320) minutes, Z=-3.680, P<0.001], while there were no statistically significant differences in blood loss during operation, time to postoperative first flatus, postoperative hospital stay, total hospital cost, tumor differentiation, and distal resection length of margin (all P>0.05). Circumferential resection margin was all negative in both groups. The number of harvested lymph modes in the TME+LLND groups was higher than that in the TME group [26 (18-37) vs. 14 (9-36), Z=-6.407, P<0.001]. In addition, there were no statistically significant differences in postoperative morbidity and Clavien-Dindo classification of complication within 30 days between the two groups (both P>0.05). Conclusions: Although robotic lateral lymph node dissection requires longer operation time, it is a feasible, safe and effective procedure.

Subjective cognitive decline and subsequent dementia: a nationwide cohort study of 579,710 people aged 66 years in South Korea

Background

Subjective cognitive decline (SCD) is a potential risk factor for dementia. We aimed to investigate the association between SCD and subsequent dementia in a nationwide population-based cohort in South Korea.

Methods

This cohort included 579,710 66-year-old adults who were followed for a total of 3,870,293 person-years (average 6.68 ± 1.33 years per person). All subjects completed a questionnaire about subjective memory impairment, the Pre-screening Korean Dementia Screening Questionnaire (KDSQ-P), which included a validated 5-item derivative, and were determined to have SCD based on a single question assessing memory decline. Depressive symptoms were assessed in all subjects using a 3-item modified geriatric depression scale. Hazard ratios were estimated using the Cox proportional hazards model and compared between subjects with and without SCD.

Results

Compared to subjects without SCD, those with SCD were more likely to develop dementia (incidence per 1000 person-years: non-SCD, 5.66; SCD, 8.59). After adjusting for potential confounding factors, the risk of subsequent dementia significantly increased in subjects with SCD, with an adjusted hazard ratio (aHR) of 1.38 (95% confidence interval [CI] 1.34 to 1.41). The risk of subsequent dementia was greatly increased in subjects with higher KDSQ-P scores (aHR = 2.77, 95% CI 2.35 to 3.27). A significant association between SCD and dementia was observed in both depressive and non-depressive symptom groups (aHR = 1.50, 95% CI 1.42 to 1.57 in subjects with depressive symptoms; aHR = 1.33, 95% CI 1.29 to 1.37 in subjects without depressive symptoms; P = 0.001).

Conclusions

In this population of 66-year-old individuals, SCD was significantly associated with an increased risk of subsequent dementia. This association was found in both depressive and non-depressive groups, with an increased risk of dementia in the presence of depressive symptoms. Our findings suggest that SCD indicates a risk for dementia. Further studies are needed to delineate potential approaches to preventing the development of dementia in individuals with SCD.

Low-dose glucocorticoid can lead to hypokalemic paralysis

Glucocorticoids are widely used in clinical practice, and a rare adverse effect of glucocorticoid administration is hypokalemic paralysis. Recently, we experienced two cases of hypokalemic paralysis after low-dose glucocorticoid administration for urticaria in healthy men. Excluding possible endocrinologic disorders, we concluded that hypokalemic paralysis could be attributed to glucocorticoid administration in our patients. Only few cases of hypokalemic paralysis induced by relatively high glucocorticoid dose are reported. In our cases, we suggest that a very low dose of glucocorticoid injection results in hypokalemic paralysis, even in healthy individuals. Clinicians should be aware that a very low dose of glucocorticoid can cause hypokalemic paralysis. Furthermore, when evaluating patient complaints of muscle weakness with hypokalemia, history of glucocorticoid administration should be thoroughly reviewed.

The Protective Effects of Increasing Serum Uric Acid Level on Development of Metabolic Syndrome

BACKGROUND

It has not been determined whether changes in serum uric acid (SUA) level are associated with incident metabolic syndrome (MetS). The aim of the current study was to investigate the relationship between changes in SUA level and development of MetS in a large number of subjects.

METHODS

In total, 13,057 subjects participating in a medical health check-up program without a diagnosis of MetS at baseline were enrolled. Cox proportional hazards models were used to test the independent association of percent changes in SUA level with development of MetS.

RESULTS

After adjustment for age, systolic blood pressure, body mass index, fat-free mass (%), estimated glomerular filtration rate, smoking status, fasting glucose, triglyceride, low density lipoprotein cholesterol, high density lipoprotein cholesterol, and baseline SUA levels, the hazard ratios (HRs) (95% confidence intervals [CIs]) for incident MetS in the second, third, and fourth quartiles compared to the first quartile of percent change in SUA level were 1.055 (0.936 to 1.190), 0.927 (0.818 to 1.050), and 0.807 (0.707 to 0.922) in male (P for trend <0.001) and 1.000 (0.843 to 1.186), 0.744 (0.615 to 0.900), and 0.684 (0.557 to 0.840) in female (P for trend <0.001), respectively. As a continuous variable in the fully-adjusted model, each one-standard deviation increase in percent change in SUA level was associated with an HR (95% CI) for incident MetS of 0.944 (0.906 to 0.982) in male (P=0.005) and 0.851 (0.801 to 0.905) in female (P<0.001).

CONCLUSION

The current study demonstrated that increasing SUA level independently protected against the development of MetS, suggesting a possible role of SUA as an antioxidant in the pathogenesis of incident MetS.

Development of a food-based index of dietary inflammatory potential for Koreans and its relationship with metabolic syndrome

BACKGROUND/OBJECTIVES

Inflammation is known to be a risk factor for metabolic diseases. This study aimed to develop a Food-based Index of Dietary Inflammatory Potential (FBDI) and examine its association with metabolic biomarkers.

SUBJECTS/METHODS

This study analyzed the raw data from the 2012-2014 Korean Genome and Epidemiology Study data of 17,771 people. To analyze the relationship between foods consumed by Koreans and inflammation, we conducted a correlation analysis between 51 food groups and hs-CRP levels. The FBDI was developed from 17 food groups selected by multiple regression method. We examined whether FBDI was associated with metabolic markers (waist circumference, blood pressure, fasting glucose, triglyceride, and HDL-cholesterol) in the 6th Korea National Health and Nutrition Examination Survey (KNHANES). We used binary logistic regression analysis to examine the association.

RESULTS

The FBDI model included seven of the anti-inflammatory food groups and three of the pro-inflammatory food groups. The FBDI formula was calculated by multiplying the intake of food group by β-coefficients derived from the multiple regression model based on the correlation analysis. The FBDI was significantly associated with waist circumference (P < 0.001), blood pressure (P < 0.001), triglyceride level (P < 0.001), and HDL-cholesterol (P < 0.001) level among adults aged 20-64 years in the KNHANES. The prevalence of metabolic syndrome was 2.618 times higher in the group with the highest FBDI than in the group with the lowest one (95% confidence interval: 1.778-3.856, P for trend < 0.001).

CONCLUSIONS

This study established an FBDI reflecting food intake patterns of Koreans, which showed a significant relationship with the prevalence of metabolic syndrome.

Association between Bone Mineral Density and Albuminuria: Cross-Sectional Analysis of Data from the 2011 Korea National Health and Nutrition Examination Survey V-2

BACKGROUND

Albuminuria is known to be independently associated with progression of renal and cardiovascular disease. However, little is known regarding the exact relationship between albuminuria and bone mineral density (BMD). The aim of this population-based study conducted in Korea was to identify the association between albuminuria and BMD.

METHODS

We performed a cross-sectional analysis of data from the Korea National Health and Nutrition Examination Survey (KNHANES V-2) 2011. BMD was measured for total hip (TH), femur neck (FN), and lumbar spine (LS). Analysis of covariance was used to compare BMD levels between the groups at the TH, FN, and LS sites, after adjusting for age. Separate analyses were performed according to sex; women were divided into two groups according to menopausal status and each group was subdivided into three according to urine albumin-to-creatinine ratio (level 1, <30 mg/g; level 2, 30 to 299 mg/g; level 3, ≥300 mg/g).

RESULTS

Data on a total of 1,831 adults (857 men and 974 women) were analyzed. In postmenopausal women, after adjusting for age, BMD of TH tended to decrease as levels of albuminuria increased (0.767±0.117, 0.757±0.129, 0.752±0.118, respectively; P=0.040). However, there was no significant difference in BMD according to albuminuria level in premenopausal women and men.

CONCLUSION

Level of albuminuria was closely related with BMD of TH in postmenopausal women, after adjusting for age, but there was no significant relationship between albuminuria and BMD in premenopausal women and men.

Utilization of Osteoporosis-Related Health Services: Use of Data from the Korean National Health Insurance Database 2008-2012

BACKGROUND

Osteoporosis and its related fractures are increasingly being recognized as major health problems because of the rapidly increasing elderly population. In this study, we investigated the annual trend of osteoporosis-related health services utilization.

METHODS

Participants aged over 50 years were identified from the Korean National Health Insurance Service database between 2008 and 2012. Health service utilization rate and treatment rate were calculated through the operational definition.

RESULTS

In this period, the number of osteoporosis patients, aged over 50 years, using the medical service, increased by 33.2%. This increase was higher in males than in females. Moreover, the number of newly diagnosed osteoporosis patients increased by 4.3% in women and 20.4% in men. To estimate the proportion of osteoporosis patients who utilize medical services, we analyzed prevalence data from the Korea National Health and Nutrition Examination Survey from 2008 to 2010. Less than 60% of patients with osteoporosis were estimated to have utilized medical services because of osteoporosis. Drug treatment rates were 34.1%, 31.1%, and 33.5% in 2008, 2009, and 2010, respectively.

CONCLUSION

This study demonstrated an increasing trend in the utilization of the osteoporosis-related health services from 2008 to 2012 in Korea. The proportion of newly diagnosed osteoporosis patients and the prevalence of access to medical services increased more in men than in women. Therefore, an increasing need for prevention and treatment of male osteoporosis was observed. The osteoporosis treatment rate was lower than that for other chronic diseases; more efforts are needed to improve awareness regarding osteoporosis treatment.

Serum 25-hydroxyvitamin D cutoffs for functional bone measures in postmenopausal osteoporosis

This study sought to determine the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health in postmenopausal women with low bone mass. A serum 25(OH)D concentration of 20 ng/mL rather than 30 ng/mL was appropriate for bone health.

INTRODUCTION

There is no consensus on the minimal serum 25-hydroxyvitamin D [25(OH)D] concentration required to maintain bone health. The aim of this study was to investigate the relationship between 25(OH)D measured via liquid chromatography-mass spectrometry (LC-MS/MS), which is the current gold standard, and biochemical markers of bone turnover, PTH, and bone mineral densitometry (BMD).

METHODS

The medical records of 750 postmenopausal women newly diagnosed with osteoporosis or osteopenia at Samsung Medical Center from 2009 to 2014 were investigated. Subjects were divided into four groups according to serum 25(OH)D concentration: <10, 10-20, 20-30, and ≥30 ng/mL. Serum concentrations of bone-specific alkaline phosphatase (BS-ALP), carboxy-terminal cross-linking telopeptide of type 1 collagen (CTx), intact PTH (iPTH), and BMD were compared among the four groups using analysis of covariance. Thresholds of 25(OH)D were then assessed using spline plots and locally weighted regression smoothing (LOESS) plots.

RESULTS

25(OH)D was negatively correlated with serum BS-ALP, CTx, and iPTH. Only femur neck and total femur BMD had significant positive relationships with 25(OH)D. Cutoff values of 11.9 and 9.7 ng/mL were estimated from the spline plots of femur neck and total femur BMD, respectively. For iPTH, the LOESS plot showed a steep decrease to a serum 25(OH)D concentration of about 20 ng/mL, followed by a plateau.

CONCLUSIONS

According to this study, a serum 25(OH)D concentration of 20 ng/mL, rather than 30 ng/mL, was appropriate for bone health.

Serum Calcium and the Risk of Incident Metabolic Syndrome: A 4.3-Year Retrospective Longitudinal Study

BACKGROUND

An association between serum calcium level and risk of metabolic syndrome (MetS) has been suggested in cross-sectional studies. This study aimed to evaluate the association between baseline serum calcium level and risk of incident MetS in a longitudinal study.

METHODS

We conducted a retrospective longitudinal study of 12,706 participants without MetS who participated in a health screening program, had normal range serum calcium level at baseline (mean age, 51 years), and were followed up for 4.3 years (18,925 person-years). The risk of developing MetS was analyzed according to the baseline serum calcium levels.

RESULTS

A total of 3,448 incident cases (27.1%) of MetS developed during the follow-up period. The hazard ratio (HR) for incident MetS did not increase with increasing tertile of serum calcium level in an age- and sex-matched model (P for trend=0.915). The HRs (95% confidence interval [CI]) for incident MetS comparing the second and the third tertiles to the first tertile of baseline serum calcium level were 0.91 (95% CI, 0.84 to 0.99) and 0.85 (95% CI, 0.78 to 0.92) in a fully adjusted model, respectively (P for trend=0.001). A decreased risk of incident MetS in higher tertiles of serum calcium level was observed in subjects with central obesity and/or a metabolically unhealthy state at baseline.

CONCLUSION

There was no positive correlation between baseline serum calcium levels and incident risk of MetS in this longitudinal study. There was an association between higher serum calcium levels and decreased incident MetS in individuals with central obesity or two components of MetS at baseline.

Delayed heart rate recovery after exercise as a risk factor of incident type 2 diabetes mellitus after adjusting for glycometabolic parameters in men

BACKGROUND

Some studies have reported that delayed heart rate recovery (HRR) after exercise is associated with incident type 2 diabetes mellitus (T2DM). This study aimed to investigate the longitudinal association of delayed HRR following a graded exercise treadmill test (GTX) with the development of T2DM including glucose-associated parameters as an adjusting factor in healthy Korean men.

MATERIAL AND METHODS

Analyses including fasting plasma glucose, HOMA-IR, HOMA-β, and HbA1c as confounding factors and known confounders were performed. HRR was calculated as peak heart rate minus heart rate after a 1-min rest (HRR 1). Cox proportional hazards model was used to quantify the independent association between HRR and incident T2DM.

RESULTS

During 9082 person-years of follow-up between 2006 and 2012, there were 180 (10.1%) incident cases of T2DM. After adjustment for age, BMI, systolic BP, diastolic BP, smoking status, peak heart rate, peak oxygen uptake, TG, LDL-C, HDL-C, fasting plasma glucose, HOMA-IR, HOMA-β, and HbA1c, the hazard ratios (HRs) [95% confidence interval (CI)] of incident T2DM comparing the second and third tertiles to the first tertile of HRR 1 were 0.867 (0.609-1.235) and 0.624 (0.426-0.915), respectively (p for trend=0.017). As a continuous variable, in the fully-adjusted model, the HR (95% CI) of incident T2DM associated with each 1 beat increase in HRR 1 was 0.980 (0.960-1.000) (p=0.048).

CONCLUSIONS

This study demonstrated that delayed HRR after exercise predicts incident T2DM in men, even after adjusting for fasting glucose, HOMA-IR, HOMA-β, and HbA1c. However, only HRR 1 had clinical significance.

Serum uric acid: A strong and independent predictor of metabolic syndrome after adjusting for body composition

BACKGROUND

Some observational studies have suggested that serum uric acid (SUA) levels are one of the determinants of the metabolic syndrome (MetS). However, previous studies reported combined results for men and women after adjusting for sex and few studies take body composition into consideration. Therefore, we performed this sex-specific longitudinal study to investigate how baseline SUA levels influence incident MetS, including body composition as an adjusting factor in a large number of subjects.

METHODS

A total of 14,442 participants (8715 men and 5727 women) participating in a medical health check-up program without diagnosed MetS at baseline were enrolled. Separate analyses were performed for men and women including body composition as a confounding factor. Cox proportional hazards models were used to quantify independent associations between SUA levels and incident MetS.

RESULTS

During 63,940person-years of follow-up, there were 4215 (2974 men, 1241 women) incident cases of MetS between 2006 and 2012. After adjustments for age, systolic BP, diastolic BP, BMI, eGFR, smoking status, TG, LDL-C, HDL-C, fasting glucose, and proportion of fat-free mass (100-fat mass, %), the hazard ratios (HR) [95% confidence interval (CI)] for incident MetS comparing the second, the third, and the fourth quartiles to the first quartile of SUA levels were 0.862 (0.770-0.965), 1.102 (0.991-1.225), and 1.246 (1.121-1.385) in men (p for trend<0.001), and 1.045 (0.862-1.266), 1.251 (1.050-1.490), and 1.321 (1.109-1.574) in women (p for trend<0.001), respectively. As a continuous variable, in fully-adjusted models, the HRs (95% CI) for incident MetS associated with each increase of 1mg/dl of SUA levels were 1.094 (1.060-1.130) in men (p<0.001) and 1.148 (1.072-1.228) in women (p<0.001), respectively.

CONCLUSION

We demonstrated that SUA levels are strong and independent predictors of MetS. This relationship remained significant after full adjustments for multiple associated confounders including body composition in both men and women.

Expression of phosphorylated histone H2AX in cultured cell lines following exposure to X-rays

PURPOSE

Exposure to ionizing radiation results in phosphorylation of histone H2AX (gammaH2AX) at sites of DNA double-strand breaks. To determine the relationship between gammaH2AX formation and radiosensitivity, the rate of formation and loss of gammaH2AX were examined in several cultured cell lines following exposure to 253 kV X-rays.

MATERIALS AND METHODS

Flow and image cytometry were both performed using a mouse monoclonal antibody against gammaH2AX. Immunoblotting was used to confirm cell line-dependent differences in antibody staining. Cell lines examined included V79 and CHO-K1 hamster cells, the human tumour cell lines SiHa, WiDr, DU145, WIL-2NS, HT144, HCC1937 and U87, and the normal cell strain HFL1. Radiosensitivity was measured using a standard clonogenic assay.

RESULTS

Using flow cytometry, gammaH2AX formation was detected 1 h after doses as low as 20 cGy. Peak levels of gammaH2AX were observed within 15-30 min after irradiation and both the rate of radiation-induced gammaH2AX formation and loss were cell type dependent. Maximum levels of gammaH2AX formation were lower for HT144 cells mutant for the ataxia telangiectasia gene. Half-times of loss after irradiation ranged from 1.6 to 7.2 h and were associated with a decrease in the total number of foci per cell. The half-time of loss of gammaH2AX was correlated with clonogenic survival for 10 cell lines (r2=0.66).

CONCLUSIONS

GammaH2AX can be detected with excellent sensitivity using both flow and image analysis. The rate of gammaH2AX loss may be an important factor in the response of cells to ionizing radiation, with more rapid loss and less retention associated with more radioresistant cell lines.

Pore-to-pore hopping model for the interpretation of the pulsed gradient spin echo attenuation of water diffusion in cell suspension systems

A simplified pore-to-pore hopping model for the two-phase diffusion problem is developed for the analysis of the pulsed gradient spin echo (PGSE) attenuation of water diffusion in the condensed cell suspension systems. In this model, the two phases inside and outside the cells are treated as two different kinds of pores, and the spin-bearing molecules perform hopping diffusion between them. The size and the orientations of those two respective pores are considered, and then the diffraction pattern of the PGSE attenuation may be well simulated. Nevertheless, the intensity of the characteristic peak decreases with increasing membrane permeability, from which the exchange time may be estimated. We then analyze the experimental 1H PGSE results of the erythrocytes suspension system. The water-residence lifetime in the erythrocyte is obtained to be 10 ms, which is the same as that estimated from the two-region approximation. Furthermore, the PGSE attenuation curve of addition of p-Chloromercuribenzenesulfonate (p-CMBS) is also discussed. It predicts that the alignment of erythrocytes will become normal to the magnetic field direction after the addition of p-CMBS, and inspection using a light microscope confirms that result.

Optimized combinations of abatement strategies for urban mobile sources

The maximum incremental reactivity (MIR) scale was chosen as a practical index for quantifying ozone-forming impacts. The integer linear and nonlinear programming techniques were employed as the optimization method to maximize MIR and volatile organic compound (VOC) reductions, and minimize ozone's marginal cost with varied control costs. Mobile vehicles were divided into nine categories according to the demands of decision makers and the distinctive features of local circumstance in metro-Taipei. The emission factor (EF) and vehicle kilometers traveled (VKT) of each kind of vehicle were estimated by MOBILE5B model via native parameters and questionnaires. Compressed natural gas (CNG) and inspection and maintenance (I/M) were the alternative control programs for buses and touring buses; liquefied petroleum gas (LPG), I/M, methanol, electrical vehicle (EV) were for taxis and low duty gasoline vehicles. EV, methanol, and I/M were the possible control methods for two-stroke and four-stroke engine motorcycles; I/M programs for low-duty diesel trucks, heavy-duty diesel trucks, and low-duty gasoline trucks. The results include the emission ratios of specific vehicle to all vehicles, the best combination of abated measures based on different objectives, and the marginal cost for ozone and VOC with varied control costs.