Prediction of various insulin resistance indices for the risk of hypertension among military young adults: the CHIEF cohort study, 2014-2020.

BACKGROUND: Non-insulin-based insulin resistance (NI-IR) indices have been reported to have an association with prevalent hypertension, however, no cohort studies to date have compared their prediction of hypertension among young adults. METHODS: A total of 2,448 military men and women, aged 18-39 years, without baseline hypertension in Taiwan were followed for incident hypertension events from 2014 until the end of 2020. All subjects underwent annual health examinations including measurements of blood pressure (BP) in mmHg. Systolic BP (SBP) 130-139/diastolic BP (DBP) < 80, SBP < 130/DBP 80-89, and SBP 130-139/DBP 80-89 were respectively defined as stage I isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH) and combined hypertension (CH). The cut-off levels of stage II hypertension for SBP and DBP were 140-159 and 90-99, respectively. Four NI-IR indices included the ratio of serum triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C), TyG index defined as ln[TG* fasting glucose (FG)/2], Metabolic Score for IR (METS-IR) defined as ln[(2* FG) + TG)* body mass index (BMI)/(ln(HDL-C))], and ZJU index defined as BMI + FG + TG + 3* alanine transaminase/aspartate transaminase (+ 2 if female). Multivariable Cox regression analysis was performed with adjustments for baseline age, sex, body mass index, BP, substance use, family history for early onset cardiovascular diseases or hypertension, low-density lipoprotein cholesterol, kidney function, serum uric acid and physical activity to determine the associations. RESULTS: During a median follow-up of 6.0 years, there were 920 hypertension events (37.6%). Greater TyG, TG/HDL-C and METS-IR indices were associated with a higher risk of stage I IDH (hazard ratios (HRs) and 95% confidence intervals: 1.376 (1.123-1.687), 1.082 (1.039-1.127) and 3.455 (1.921-6.214), respectively), whereas only greater ZJU index was associated with a higher risk of stage II IDH [HRs: 1.011 (1.001-1.021)]. In addition, greater ZJU index was associated with a higher risk of stage II ISH [HR: 1.013 (1.003-1.023)], and greater TyG index was associated with a higher risk of stage II CH [HR: 2.821 (1.244-6.395)]. CONCLUSION: Insulin resistance assessed by various NI-IR indices was associated with a higher risk of hypertension in young adults, while the assessment ability for specific hypertension category may differ by NI-IR indices.

Electrocardiographic and echocardiographic predictors of greater carotid intima-media thickness in tactical athletes: The CHIEF atherosclerosis study.

OBJECTIVE: Both electrocardiographic and echocardiographic left ventricular hypertrophy (LVH) have been reported with an association with greater carotid intima-media thickness (cIMT), a marker of subclinical atherosclerosis in patients with hypertension, while the associations are unclear in physically fit young adults. METHODS: A total of 1822 Taiwanese military personnel, aged 18-40 years, received an annual health examination including electrocardiography (ECG) and echocardiography in 2018-2020. Left carotid bulb cIMT was measured by high-resolution ultrasonography. Multiple logistic regression analysis with adjustments for age, sex, smoking, alcohol consumption, body mass index, mean blood pressure, and physical fitness was used to determine the associations between echocardiographic and ECG parameters and the highest quintile of cIMT (≥0.8 mm). RESULTS: Cornell-based LVH, Myers et al.-based RVH and heart rate ≥75/min were associated with cIMT ≥0.8 mm [odds ratios (ORs) and 95% confidence intervals: 1.54 (1.01, 2.35), 1.66 (1.18, 2.33), and 1.39 (1.06, 1.83), respectively], while echocardiographic LVH defined as ≥46.0 g/m2.7 for men and ≥38.0 g/m2.7 for women was inversely associated with cIMT ≥0.8 mm [OR: 0.45 (0.24, 0.86)]. CONCLUSION: In tactical athletes of military, the associations of ECG and echocardiographic LVH with cIMT were in opposite directions. Higher physical fitness may cause cardiac muscle hypertrophy and reduce the atherosclerosis severity, possibly leading to the paradoxical echocardiographic finding. This study suggests that ECG-based LVH remains a good marker of subclinical atherosclerosis in our military population.

Mitral valve prolapse and physical performance in Asian military males: The CHIEF Heart study.

The impact of mitral valve prolapse (MVP) and mitral regurgitation (MR) on physical performance has not been examined. Of 1,808 physically fit Asian military males, we compared the physical fitness between 62 subjects with MVP (MVP(+)) and 1,311 age- and anthropometrics-matched controls from the 1,746 participants without MVP (MVP(-)). MVP and MR grade were defined based on the American Society of Echocardiography criteria. Aerobic endurance capacity was evaluated by a 3000-m run and muscular endurance capacity was separately evaluated by 2-min sit-ups and 2-min push-ups. Analysis of covariance was used to determine the difference between groups. As compared to the MVP(-), the MVP(+) completed the 3000-m run test faster (839.2 ± 65.3 sec vs. 866.6 ± 86.8 sec, p = 0.019), but did fewer push-ups (41.3 ± 3.92 vs. 48.0 ± 10.1, p = 0.02) and similar sit-ups within 2 min. Of the MVP(+), those with any MR (trivial, mild or moderate) completed the 3000-m run test faster than those without MR (830.6 ± 61.7 sec vs. 877.2 ± 61.7 sec, p = 0.02). Our findings suggest that in physically active Asian military males, the MVP(+) may have greater aerobic endurance capacity but lower muscular endurance capacity than the MVP(-). The presence of MR may play a role for the MVP(+) to have greater aerobic endurance capacity.

Fusion extracted features from deep learning for identification of multiple positioning errors in dental panoramic imaging.

BACKGROUND: Dental panoramic imaging plays a pivotal role in dentistry for diagnosis and treatment planning. However, correctly positioning patients can be challenging for technicians due to the complexity of the imaging equipment and variations in patient anatomy, leading to positioning errors. These errors can compromise image quality and potentially result in misdiagnoses. OBJECTIVE: This research aims to develop and validate a deep learning model capable of accurately and efficiently identifying multiple positioning errors in dental panoramic imaging. METHODS AND MATERIALS: This retrospective study used 552 panoramic images selected from a hospital Picture Archiving and Communication System (PACS). We defined six types of errors (E1-E6) namely, (1) slumped position, (2) chin tipped low, (3) open lip, (4) head turned to one side, (5) head tilted to one side, and (6) tongue against the palate. First, six Convolutional Neural Network (CNN) models were employed to extract image features, which were then fused using transfer learning. Next, a Support Vector Machine (SVM) was applied to create a classifier for multiple positioning errors, using the fused image features. Finally, the classifier performance was evaluated using 3 indices of precision, recall rate, and accuracy. RESULTS: Experimental results show that the fusion of image features with six binary SVM classifiers yielded high accuracy, recall rates, and precision. Specifically, the classifier achieved an accuracy of 0.832 for identifying multiple positioning errors. CONCLUSIONS: This study demonstrates that six SVM classifiers effectively identify multiple positioning errors in dental panoramic imaging. The fusion of extracted image features and the employment of SVM classifiers improve diagnostic precision, suggesting potential enhancements in dental imaging efficiency and diagnostic accuracy. Future research should consider larger datasets and explore real-time clinical application.

Asian Female Athlete's Heart: The CHIEF Heart Study.

Background: The cardiac characteristics of Asian female endurance athletes and strength athletes have rarely been investigated. Methods: This study included 177 Taiwanese young women undergoing military training. Cardiac features were assessed by electrocardiography (ECG) and echocardiography. Then, all participants completed a 3000-meter run to assess endurance capacity, and 89 participants completed a 2-minute push-up test to assess muscular strength. Athletes were those whose exercise performance fell one standard deviation above the mean, and the remaining participants were defined as controls. Multiple logistic regression analysis was used to determine the predictors of the cardiac characteristics of female athletes. Results: Compared to the female controls, female endurance athletes had a greater QRS duration (ms) (92.12 ± 10.35 vs. 87.26 ± 9.89, p = 0.01) and a higher prevalence of right axis deviation (RAD) (34.9% vs. 11.1%, p < 0.001). There were no differences in any echocardiographic parameters. Greater QRS duration and RAD and lower systolic blood pressure were independent predictors of female endurance athletes [odds ratios (OR) and 95% confidence intervals: 1.05 (1.01-1.09), 2.91 (1.12-7.59) and 0.93 (0.88-0.98), respectively]. Female strength athletes had a greater right ventricular outflow tract (RVOT) (mm) (28.06 ± 3.57 vs. 25.38 ± 3.61, p = 0.007) but revealed no differences in ECG variables. Greater RVOT was the only predictor of female strength athletes [OR: 1.26 (1.05-1.50)]. Conclusions: In Asian military women, a wider QRS duration and the presence of RAD in ECG rather than heart structure and function were found to characterize endurance athletes, whereas a wider RVOT but no ECG features were found to characterize strength athletes.

Association of hepatic and systemic inflammation with localized stage II/III periodontitis in young males: The CHIEF oral health study.

AIM: To clarify the association between systemic and hepatic inflammation and localized periodontitis which has been reported to vary among races. MATERIALS AND METHODS: The study included 1112 military males, aged 18-40 years, in Taiwan. Participants were classified as periodontally healthy/stage I (n = 796) or stage II/III periodontitis (n = 316), according to the 2017 world workshop criteria. Systemic and hepatic inflammation were defined by the highest tertiles of blood leukocyte counts (7.51 × 103 /µl) and alanine aminotransferase (30 U/L), respectively. Multiple logistic regression analysis with adjustments for age, metabolic syndrome, betel nut consumption and smoking was carried out. RESULTS: There was a significant association between high systemic inflammation, irrespective of hepatic inflammation severity, and localized stage II/III periodontitis (odds ratio [OR], 1.62 [1.09-2.42] and 1.47 [1.00-2.15], respectively, in the presence of high or no hepatic inflammation. However, no significant association was found among participants with low systemic inflammation, irrespective of the severity of hepatic inflammation (OR, 1.31 [0.91-1.91]). CONCLUSIONS: An association between hepatic inflammation and localized periodontitis in Taiwanese was observed only if systemic inflammation coexisted, possibly accounting for the reported differences in the association between Japanese and non-Asian populations in prior studies.

Erythrocyte indices and localized stage II/III periodontitis in military young men and women: CHIEF oral health study.

BACKGROUND: Prior studies have shown an association between generalized periodontitis and anemia in older or undernourished adults. The aim of the study was to examine the associations of erythrocyte indices with localized periodontitis in robust young adults, which has never been reported before. METHODS: The study included 1286 military participants, aged 19-40 years, with regular exercise training in Hualien, Taiwan. Localized periodontitis was grouped to healthy/stage I and stage II/III (n = 803 and 325) in men and (n = 130 and 28) in women according to the 2017 criteria of the world workshop. Systemic inflammation was evaluated by leukocyte counts. Multiple logistic regression analysis with adjustment for age, tobacco smoking status, betel nut chewing status, body mass index and leucocyte counts were used to determine the associations. RESULTS: Greater mean corpuscular volume in young men [odds ratio (OR) and 95% confidence intervals 1.03 (1.01-1.06)], and greater hematocrit and hemoglobin levels in young women were associated with a higher risk of localized stage II/III periodontitis [OR: 1.17 (1.02-1.34) and 1.60 (1.06-2.41), respectively]. However, there were no associations for erythrocyte counts. CONCLUSIONS: The localized stage II/III periodontitis risk increased with greater erythrocyte indices in robust young adults. This finding could be explained in part by that localized periodontitis may promote physical stress, possibly resulting in an increase of erythrocyte indices. On the other side, greater physical fitness associated with a lower risk of periodontitis may consume iron storage in the body, leading to exercise-induced anemia or smaller erythrocyte volume.

Dental caries and periodontitis and the risk of myopia in young adults: CHIEF oral health study.

AIM: Oral health and ocular diseases may be associated with collagen defects and inflammation status. However, the results from prior studies are conflicting. The aim of this study was to explore the association of dental caries and periodontitis with myopia in young adults. MATERIALS AND METHODS: A total of 938 military personnel aged 19-39 years receiving both oral and eye examinations from 2018 through 2020 were included in this study in Taiwan. The severity of myopia was graded as no myopia (diopters > - 0.5, N = 459), low myopia (diopters: - 0.5 to -5.9, N = 225) and high myopia (diopters ≤ - 6.0, N = 254). A multiple logistic regression analysis with adjustments for age, body mass index, systolic blood pressure, smoking, alcohol consumption, missing teeth numbers, blood leucocyte counts, triglycerides, high-density lipoprotein, and uric acid were used to determine the associations of actively dental caries, filled teeth and stage II/III periodontitis with myopia. RESULTS: The presence of any actively dental caries was significantly associated with a higher risk of any myopia (low or high) (odds ratio [OR] and 95% confidence intervals [95% CI] 1.42 [1.04-1.94]), whereas there was no association for filled teeth. Moreover, the association for stage II/III periodontitis was only observed with high myopia (OR: 1.52 [1.07-2.15]) and was not observed with low myopia. CONCLUSIONS: Our findings suggest that only actively dental caries and a higher severity of periodontitis were associated with myopia among young adults, thus highlighting the dental inflammation status in the oral cavity as a potential link to ocular diseases.

Associations between metabolic biomarkers and localized stage II/III periodontitis in young adults: The CHIEF Oral Health study.

AIM: To investigate the associations between metabolic risk factors and periodontitis in young adults. MATERIALS AND METHODS: The study included 1123 participants, aged 19-40 years, in Taiwan. Metabolic syndrome components were defined by the International Diabetes Federation criteria. Localized periodontitis was graded to healthy (n = 828) and stage II/III (n = 295) according to the 2017 criteria of the World Workshop. Multiple logistic regression analysis with adjustment for sex, age, betel nut consumption, and smoking were used to determine the associations. RESULTS: Greater waist circumference, serum triglycerides, and serum uric acid were associated with higher localized stage II/III periodontitis risk [odds ratio (OR) and 95% confidence interval (CI): 1.04 (1.02-1.05), 1.004 (1.002-1.006), and 1.10 (1.00-1.21), respectively]. There were no associations for total cholesterol, high-density lipoprotein, and blood pressure. There was a non-linear association between fasting glucose and localized stage II/III periodontitis, where the turning point was 105 mg/dl [OR: 0.97 (0.95-0.99) and 1.06 (1.00-1.13) when the levels were <105 and ≥105 mg/dl, respectively]. CONCLUSIONS: The risks of localized stage II/III periodontitis vary with metabolic components, in which waist circumference, serum triglycerides, and serum uric acid are the risk factors, whereas plasma glucose shows a non-linear relationship in young adults.

Association of red blood cell size and physical fitness in a military male cohort: The CHIEF study.

Anemia manifested as reduced red blood cell (RBC) amounts or hemoglobin levels has been associated with lower cardiorespiratory fitness. However, the relationship of smaller RBC with physical fitness was unknown. We included 2933 non-anemic military males (hemoglobin levels: 11.1-15.9 g/dL and mean corpuscular volume (MCV) <100 fL) in Taiwan during 2014. Aerobic fitness was assessed by time for a 3000-meter run, and anaerobic fitness was evaluated by numbers of sit-ups and push-ups, each performed within 2 minutes. Multiple linear and logistic regression models adjusting for age, service specialty, lipid profiles, and hemoglobin levels were used to determine the associations. Microcytosis and normocytosis were defined as MCV ≤ 70 fL (n = 190) and MCV > 70 fL (n = 2743), respectively. The linear regression shows that as compared with microcytosis, normocytosis was associated with more numbers of sit-ups performed within 2 minutes (ß = 1.51, P-value = 0.02). The logistic regression also reveals that those males with microcytosis had higher probability as the worst 10% performers in the 2-minute push-up test (odds ratio: 1.91, 95% confidence intervals: 1.18-3.12). By contrast, there was no association of microcytosis with 3000-meter running time. Our study suggests that non-anemic microcytosis was associated with lower anaerobic fitness but not with aerobic fitness. Whether the causative factors for microcytosis such as iron deficiency status and thalassemia trait unavailable in the study might account for the relationship needs further investigations.

Association of Single Measurement of dipstick proteinuria with physical performance of military males: the CHIEF study.

BACKGROUND: Proteinuria, a marker of kidney injury, may be related to skeletal muscle loss. Whether the severity of proteinuria is associated with physical performance is unclear. METHODS: We examined the association of proteinuria severity with physical performance cross-sectionally in 3357 military young males, free of chronic kidney disease, from the cardiorespiratory fitness and hospitalization events in armed Forces (CHIEF) study in Taiwan. The grades of proteinuria were classified according to one dipstick urinalysis which were collected at morning after an 8-h fast as unremarkable (0, +/-, and 1+), moderate (2+) and severe (3+ and 4+). Aerobic physical performance was evaluated by time for a 3000-m run and anaerobic physical performance was evaluated by numbers of 2-min sit-ups and 2-min push-ups, separately. Multiple linear regressions were used to determine the relationship. RESULTS: As compared with unremarkable proteinuria, moderate and severe proteinuria were dose-dependently correlated with 3000-m running time (ß: 4.74 (95% confidence intervals (CI): - 0.55, 10.02) and 7.63 (95% CI: 3.21, 12.05), respectively), and inversely with numbers of 2-min push-ups (ß = - 1.13 (- 1.97, - 0.29), and - 1.00 (- 1.71, - 0.28), respectively) with adjustments for age, service specialty, body mass index, blood pressure, alcohol intake, smoking, fasting plasma glucose, blood urea nitrogen, serum creatinine and physical activity. However, there was no association between proteinuria severity and 2-min sit-ups. CONCLUSIONS: Our findings show a relationship of dipstick proteinuria with aerobic physical performance and parts of anaerobic physical performance in military healthy males. This mechanism is not fully understood and requires further investigations.

Association of betel nut chewing with exercise performance in a military male cohort: the CHIEF study.

INTRODUCTION: Betel nut chewing may cause obesity, neurohormonal activation and inflammation, possibly impairing exercise performances. METHODS: We examined the cross-sectional association in 4388 military male adults aged 18-50 years from the cardiorespiratory fitness in armed forces study in Taiwan between 2013 and 2014. The status of betel nut chewing was classified as current and former/never based on each participant's response to a questionnaire. Physical fitness was evaluated by three basic exercise tests including 3000 m running, 2 min sit-ups and 2 min push-ups. Multiple logistic regression for the best 10% and the worst 10% performers in each exercise, and linear regression were used to determine the relationship. RESULTS: There were 564 current chewers and 3824 non-current chewers for the analysis. The linear regression shows that current betel nut chewing was positively correlated with 3000 m running duration (r=0.37, p=0.042) after adjusting for age, service specialty, body mass index, exercise frequency and alcohol intake. In addition, the logistic regression shows that as compared with non-current chewers, current chewers had lower odds of being the top 10% performers in 2 min push-ups and higher odds of being the bottom 10% performers in 2 min sit-ups (ORs and 95% CIs: 0.71 (0.50 to 0.99) and 1.32 (1.00 to 1.75), respectively). However, the associations between betel nut chewing and physical fitness were all insignificant after further adjusting for current smoking. CONCLUSIONS: Our findings suggest that the impairment of physical fitness associated with betel nut chewing of military young men might be mainly mediated or moderated by the coexisted cigarette smoking.

A comparison of various insulin resistance indices and the possibility of hypertension in military adults: CHIEF study.

BACKGROUND: Insulin resistance is associated with the development of hypertension, whereas there were rare studies comparing various non-insulin based insulin resistance (NI-IR) indices for the possibility of hypertension among young and middle-aged adults. METHODS: This cross-sectional study included a total of 4,080 military personnel, aged 18-50 years, without antihypertensive medications therapy in 2014. All subjects received annual health examinations for blood pressure (BP) measurements. Stage I isolated diastolic hypertension (IDH) and isolated systolic hypertension (ISH) and combined hypertension were respectively defined as systolic BP (SBP) < 130 mmHg/diastolic BP (DBP) 80-89 mmHg, SBP 130-139 mmHg/DBP < 80 mmHg, and SBP 130-139 mmHg/DBP 80-89 mmHg. The cut-off values of stage II hypertension for SBP and DBP were 140-159 mmHg and 90-99 mmHg, respectively. Four NI-IR indices included the serum triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C) ratio, TyG index, Metabolic Score for IR (METS-IR) and ZJU index which were defined according to their specific formula. Multiple logistic regression analysis with adjustments for age, sex, anthropometrics, substance use, kidney function, serum uric acid, atherogenic cholesterols and physical activity was performed to determine the associations. RESULTS: There were 1,024 subjects with hypertension (25.1%) in which 739 were stage I hypertension, and 285 were stage II hypertension. For total hypertension, there were an association with TyG and METS-IR indices [odds ratios (ORs) and 95% confidence intervals: 1.432 (1.215-1.688) and 1.553 (1.040-2.321), respectively]. For hypertension subtypes, TyG index was positively associated with overall, stage I, and stage II ISH [ORs: 1.447 (1.149-1.823), 1.317 (1.029-1.687), and 2.011 (1.351-2.994), respectively], while TG/HDL-C, METS-IR and ZJU indices were merely associated with stage II ISH [ORs: 1.053 (1.006-1.103), 3.001 (1.171-7.696) and 1.009 (1.000-1.017), respectively]. In addition, TyG and METS-IR indices were positively associated with stage II IDH [ORs: 1.813 (1.207-2.721) and 2.85 (1.080-7.520), respectively], and TyG index was also associated with combined hypertension [OR: 1.425 (1.007-1.833)]. CONCLUSION: Among young and middle-aged adults, insulin resistance assessed by the four NI-IR indices was positively associated with stage II ISH, while only TyG index had a significant association for both stage II IDH and combined hypertension.

Does the guideline-based physical activity level for cardiovascular health also benefit periodontal health?

Abstract Background/purpose: It is unclear about whether the guideline-based physical activity (PA) level for cardiovascular health also benefits periodontal health. Therefore, this study aimed to clarify the association between guideline-based PA levels and periodontitis in young adults. Materials and methods: This was a cross-sectional study which included 334 military participants, aged 18-44 years in Taiwan. The PA level was assessed by total running time per week (wk) in the past 6 months from a self-reported questionnaire, and was classified as moderate intensity PA <150, 150-299, and ≥300 min/wk according to the American guideline for cardiovascular health. Periodontitis was defined based on the 2017 World Workshop. Multiple logistic regression analysis was used to determine the association with adjustment for age, sex, educational level, tobacco smoking, alcohol intake, body mass index, waist circumference, blood pressure and teeth brushing frequency. Results: As compared to the PA: 150-299 min/wk, the PA <150 min/wk was associated with a greater possibility of periodontitis (odds ratio (OR): 2.45 (95% confidence interval (CI): 1.24-4.82), whereas the PA ≥300 min/wk was not associated with periodontitis (OR: 0.98 (95% CI: 0.13-1.09)) in young adults. Conclusion: The guideline-based moderate intensity PA level ≥150 min/wk is found to have superior periodontal health in young adults. However, there is no additional benefit in more exercise time to obtain better periodontal health when the suggested PA level has been achieved.

The combined effect of cardiorespiratory and muscular fitness on the incidence of metabolic syndrome before midlife.

BACKGROUND: Cardiorespiratory fitness (CRF) could reduce the risk of metabolic syndrome (MetS) while the association between muscular endurance capacity (MEC) and incident MetS has rarely been investigated in young adults. METHODS: A total of 2890 military men and women, aged 18-39 years, free of baseline MetS in Taiwan, were followed for incident MetS from baseline (2014) until the end of 2020. All subjects received annual health examinations for assessment of MetS. Physical fitness was assessed by CRF (estimated maximal oxygen uptake, VO2 max [mL/kg/min], in a 3000-m run) and MEC (numbers of 2-min push-ups). MetS was defined according to the International Diabetes Federation (IDF) criteria. Multiple Cox regression analysis was conducted with adjustments for baseline age, sex, substance use status and physical activity to determine the associations of CRF and MEC with incidences of new-onset MetS and related features, for example, central obesity, hypertension, dyslipidaemia and prediabetes or diabetes. To examine the combined effects of CRF and MEC status on incidence of MetS, high and low levels of CRF and MEC were separately defined by over and under the sex-specific median in each exercise test. RESULTS: During a median follow-up of 5.8 years, there were 673 (23.3%) new-onset MetS. Higher CRF was associated with a lower incidence of MetS (hazard ratio [HR] and 95% confidence interval: 0.905 [0.877-0.933]), and its components separately, except hypertension. No association was observed between MEC and incident MetS, and its components separately, except hypertension. When evaluating the combined effects of MEC and CRF status on the incidence of MetS, it was observed that compared with the low CRF/low MEC, the high CRF/high MEC (HR: 0.553 [0.439-0.697]) and the high CRF/low MEC (HR: 0.730 [0.580-0.918]) had a lower incidence of new-onset MetS (P value for the intergroup difference = 0.04). There was no significant result for the low CRF/high MEC. CONCLUSIONS: This study highlights that although the protective effects of MEC to reduce the incidence of MetS and most of its related features were mainly driven by CRF in young adults, there was an addictive effect of greater MEC on CRF to prevent the development of new-onset MetS before midlife.

Obesity Phenotypes and Dental Calculus in Young Adults: CHIEF Oral Health Study.

AIM: The study aimed to examine the association of obesity phenotypes with dental calculus. BACKGROUND: Obesity has been recognized as a risk factor for kidney and gallbladder stones formation and periodontitis. OBJECTIVE: We have investigated the association between obesity, metabolic risk factors, and dental calculus, which is a sequela following periodontitis. METHODS: This study included 5,281 military members, aged 19-45 years, without antihypertensive medications in Taiwan. Obesity was defined as body mass index ≥27.5 kg/m2, and metabolic syndrome (MetS) was defined according to the modified ATP III criteria. Supragingival calculus in any teeth, except for impacted teeth and the third molar, was the outcome of interest. Multiple linear regression analysis with adjustments for age, sex, toxic substance use, brushing teeth frequency, and blood leukocyte counts, was used to determine the association of obesity with dental calculus numbers. Multiple logistic regression analysis was used to assess the association between obesity with or without MetS and the presence of any dental calculus. RESULTS: BMI was positively correlated to dental calculus numbers [ß and confidence intervals (CI) = 0.023 (0.014, 0.032)]. Compared to the obesity(-)/MetS(-) group, there were dosedependent associations for the obesity(-)/MetS(+), obesity(+)/MetS(-), and obesity(+)/MetS(+) groups with the presence of any dental calculus [odds ratios (ORs): 1.08 (0.76, 1.53), 1.31 (1.08, 1.58), and 1.51 (1.20, 1.90), respectively]. Of the metabolic risk factors, abdominal obesity and hypertension were independently associated with dental calculus [ORs: 1.33 (1.13, 1.55) and 1.30 (1.11, 1.52), respectively]. CONCLUSION: This study suggests general obesity as an independent risk factor for dental calculus formation, and MetS, particularly the components of abdominal obesity, and hypertension may also increase the prevalence of dental calculus. Diet control and regular exercise might be preventive measures for the development of both obesity and dental calculus.

Substance use and incidence of metabolic syndrome before midlife among military adults: the CHIEF cohort study.

Backgrounds: Habitual substance use, i. e., alcohol, tobacco and betel nut, has been found with an increased risk of metabolic syndrome (MetS) in the general population, whereas the association remains unclear in physically fit military personnel. This study aimed to investigate the combination of these substances use and their associations with new-onset MetS in the military. Methods: A total of 2,890 military men and women, aged 18-39 years, without MetS were obtained from the cardiorespiratory fitness and health in eastern armed forces study (CHIEF) in Taiwan and followed for incident MetS from baseline (2014) through the end of 2020. Incident MetS event was defined by the International Diabetes Federation guideline and confirmed in the annual health examinations. A self-report was used to assess the alcohol, tobacco and betel nut use status (active vs. former/never). Multivariable Cox regression model was performed to determine the association with adjustments for sex, age, body mass index and physical activity at baseline. Results: At baseline, there were 279 active betel nut chewers (9.7%), 991 active smokers (34.3%) and 1,159 active alcohol consumers (40.1%). During a mean follow-up of 6.0 years, 673 incident MetS (23.3%) were observed. As compared to no substance users, only one substance, and two and three substances users had a greater risk of incident MetS [hazard ratios (HRs) and 95% confidence intervals: 1.27 (1.06-1.54), 1.38 (1.12-1.69) and 1.78 (1.37-2.32), respectively]. In subgroup analyses, the risk of incident MetS in two and three substances users was significantly greater in those free of baseline low high-density lipoprotein [HRs: 1.54 (1.21-1.95) and 2.57 (1.92-3.46), respectively], as compared to their counterparts (both p for interactions <0.05). Conclusion: A dose-response association of more substances use for new-onset MetS was noted in military personnel. This finding suggests that the combined alcohol, tobacco and betel nut use may play a role in the development of MetS. Further study is required to establish causation and to investigate the potential benefits of substance use cessation in reducing the risk of MetS.

Oral health and physical performance in Asian military males: The cardiorespiratory fitness and health in armed forces.

Background/purpose: It is unclear about whether the oral health has impact on physical performance. Therefore, this study aimed to examine the association between oral health and physical performance in 300 military adults in Taiwan. Materials and methods: Oral health was assessed by the presence of periodontitis and dental caries. The status of cardiorespiratory and muscular endurance capacity was respectively assessed by tertiles of time for a 3000-m run and 2-min push-up numbers. Multivariable logistic and linear regression analyses with adjustments for age, smoking, alcohol drinking, blood pressure, anthropometric variables, lipid profile, fasting glucose and physical activity were used to determine the association. Results: Participants with periodontitis were more likely to have worse 3000-m running performance classified in the lowest tertile [odds ratio (OR) and 95% confidence interval: 1.94 (1.03, 3.66)]. Participants with any dental caries were more likely to have worse push-ups performance classified in the lowest tertile [OR: 2.50 (1.27, 4.92)]. In linear regression analyses, dental caries numbers were inversely correlated with 2-min push-ups numbers [ß = -1.04 (-2.07, -0.01)]. Conclusion: This study suggests that oral health is crucial to maintain physical fitness, and dental caries and periodontitis may affect differently on aerobic and muscular endurance capacities.

Estimated power output for a distance run and maximal oxygen uptake in young adults.

Background: Both cardiopulmonary exercise testing (CPET) and run field tests are recommended by the American Heart Association for assessing the maximal oxygen uptake (VO2 max) of youth. Power output was highly correlated with VO2 max in CPET. However, it is unclear regarding the correlations of time and estimated power output (EPO) for a run field test with VO2 max obtained from CPET in young adults. Methods: This study included 45 participants, aged 20-40 years, from a sample of 1,120 military personnel who completed a 3,000-m run field test in Taiwan in 2020. The participants subsequently received CPET using the Bruce protocol to assess VO2 max in the same year. According to the physics rule, EPO (watts) for the run field test was defined as the product of half body mass (kg) and [distance (3000-m)/time (s) for a run field test]. Pearson product-moment correlation analyses were performed. Results: The Pearson correlation coefficient (r) of time against EPO for the run field test was estimated to be 0.708 (p <0.001). The correlation coefficient between the time for the run field test and VO2 max (L/min) in CPET was estimated to be 0.462 (p = 0.001). In contrast, the correlation coefficient between time for the run field test and VO2 max scaled to body mass in CPET was estimated to be 0.729 (p <0.001). The correlation coefficient of EPO for the run field test against VO2 max in CPET was estimated to be 0.813 (p <0.001). Conclusion: In young adults, although the time for a run field test was a reliable estimate of VO2 max scaled to body mass, EPO proportional to the mean square velocity was found as a superior estimate of VO2 max.