Predictive value of the initial MELD score and its derivative scores for early survival rate after liver transplantation in patients with liver failure / 器官移植

Objective To explore the predictive values of the initial model for end-stage liver disease (MELD) score, MELD combined with serum sodium (MELD-Na) score and MELD combined with serum lactic acid (MELD-Lac) score for early survival rate after liver transplantation in patients with liver failure. Methods Clinical data of 135 recipients undergoing liver transplantation for liver failure were retrospectively analyzed. All patients were divided into the early survival group (n=110) and early death group (n=25) according to the survival at postoperative 28 d. Clinical data were compared between two groups. The optimal cut-off values of MELD, MELD-Na and MELD-Lac scores for predicting early survival rate after liver transplantation in patients with liver failure were determined by the receiver operating characteristic (ROC) curve. The predictive values of different scores for early survival rate after liver transplantation in patients with liver failure were evaluated. Results Significant differences were observed in the initial MELD, MELD-Na and MELD-Lac scores after liver transplantation between two groups (all P < 0.05). For the initial MELD, MELD-Na and MELD-Lac scores in predicting early survival rate after liver transplantation in patients with liver failure, the AUC were 0.653 [95% confidence interval (CI) 0.515-0.792], 0.648 (95%CI 0.514-0.781) and 0.809 (95%CI 0.718-0.900), the optimal cut-off values were 18.09, 18.09 and 19.97, Youden's indexes were 0.398, 0.380 and 0.525, the sensitivity was 0.680, 0.680 and 0.840, and the specificity was 0.720, 0.700 and 0.690, respectively. The AUC of MELD-Lac score was higher than those of MELD and MELD-Na scores, and the differences were statistically significant (both P < 0.05). Conclusions Compared with the initial MELD and MELD-Na scores after liver transplantation, the initial MELD-Lac score is a more reliable index for predicting early survival rate after liver transplantation in patients with liver failure.

Development of Plantar Force Assessment Model for Patients with Patellofemoral Pain / 医用生物力学

Objective To develop plantar force model of patellofemoral pain (PFP), so as to provide theoretical references for the assessment of PFP rehabilitation. Methods The case-control study was conducted, and a total of 126 patients with PFP and 126 healthy controls matched by gender and age were enrolled in the study. The participants were tested for plantar force and pressure during level walking, and twelve plantar regions were divided and recorded. Whether the participants suffered PFP was analyzed as dependent variable, meanwhile the peak force and peak pressure in 12 plantar regions of participants at selected speed during level walking were analyzed as independent variables. Conditional logistic regression (CLR) equations of peak force and peak pressure with PFP were established, respectively. The receiver-operating characteristic (ROC) curve of the corresponding equations was derived, and the area under ROC curve was calculated to analyzed the validity of different equations on PFP assessment. Results The CLC equation of peak force in 12 plantar regions of the participants with FFP was constructed, and only peak force of lateral heel was in the equation. The CLC equation of peak pressure in each plantar region included medial heel, midfoot, 1st and 2nd metatarsals. Meanwhile, the area under ROC curve of the pressure equation was larger than that of the force equation. Conclusions Peak force and pressure at different plantar regions can be used to assess PFP during level walking, and peak pressure is more effective for assessment.

Automatic Identification of Brain Injury Mechanism Based on Deep Learning / 法医学杂志

OBJECTIVES@#To apply the convolutional neural network (CNN) Inception_v3 model in automatic identification of acceleration and deceleration injury based on CT images of brain, and to explore the application prospect of deep learning technology in forensic brain injury mechanism inference.@*METHODS@#CT images from 190 cases with acceleration and deceleration brain injury were selected as the experimental group, and CT images from 130 normal brain cases were used as the control group. The above-mentioned 320 imaging data were divided into training validation dataset and testing dataset according to random sampling method. The model classification performance was evaluated by the accuracy rate, precision rate, recall rate, F1-value and AUC value.@*RESULTS@#In the training process and validation process, the accuracy rate of the model to classify acceleration injury, deceleration injury and normal brain was 99.00% and 87.21%, which met the requirements. The optimized model was used to test the data of the testing dataset, the result showed that the accuracy rate of the model in the test set was 87.18%, and the precision rate, recall rate, F1-score and AUC of the model to recognize acceleration injury were 84.38%, 90.00%, 87.10% and 0.98, respectively, to recognize deceleration injury were 86.67%, 72.22%, 78.79% and 0.92, respectively, to recognize normal brain were 88.57%, 89.86%, 89.21% and 0.93, respectively.@*CONCLUSIONS@#Inception_v3 model has potential application value in distinguishing acceleration and deceleration injury based on brain CT images, and is expected to become an auxiliary tool to infer the mechanism of head injury.

Multivariate Analysis of Solid Pulmonary Nodules Smaller than 1 cm in Distinguishing Lung Cancer from Intrapulmonary Lymph Nodes / 中国肺癌杂志

BACKGROUND@#Preoperative diagnosis and differential diagnosis of small solid pulmonary nodules are very difficult. Computed tomography (CT), as a common method for lung cancer screening, is widely used in clinical practice. The aim of this study was to analyze the clinical data of patients with malignant pulmonary nodules and intrapulmonary lymph nodes in the clinical diagnosis and treatment of <1 cm solid pulmonary nodules, so as to provide reference for the differentiation of the two.@*METHODS@#Patients with solid pulmonary nodules who underwent surgery from June 2017 to June 2020 were analyzed retrospectively. The clinical data of 145 nodules (lung adenocarcinoma 60, lung carcinoid 2, malignant mesothelioma 1, sarcomatoid carcinoma 1, lymph node 81) were collected and finally divided into two groups: lung adenocarcinoma and intrapulmonary lymph nodes, and their clinical data were statistically analyzed. According to the results of univariate analysis (χ² test, t test), the variables with statistical differences were selected and included in Logistic regression multivariate analysis. The predictive variables were determined and the receiver operating characteristic (ROC) curve was drawn to get the area under the curve (AUC) value of the area under the curve.@*RESULTS@#Logistic regression analysis showed that the longest diameter, Max CT value, lobulation sign and spiculation sign were important indicators for distinguishing lung adenocarcinoma from intrapulmonary lymph nodes, and the risk ratios were 106.645 (95%CI: 3.828-2,971.220, P<0.01), 0.980 (95%CI: 0.969-0.991, P<0.01), 3.550 (95%CI: 1.299-9.701, P=0.01), 3.618 (95%CI: 1.288-10.163, P=0.02). According to the results of Logistic regression analysis, the prediction model is determined, the ROC curve is drawn, and the AUC value under the curve is calculated to be 0.877 (95%CI: 0.821-0.933, P<0.01).@*CONCLUSIONS@#For <1 cm solid pulmonary nodules, among many factors, the longest diameter, Max CT value, lobulation sign and spiculation sign are more important in distinguishing malignant pulmonary nodules from intrapulmonary lymph nodes.

Clinical study of value of serum Klotho level of elderly donors in predicting postoperative renal graft function in recipients / 器官移植

Objective To explore the feasibility of serum Klotho level in the elderly donors to predict the renal graft function in the recipients. Methods Clinical data of 16 elderly donors and 27 recipients undergoing renal transplantation were collected. The general status of the recipients was observed. The levels of serum Klotho and serum creatinine (Scr) in the elderly donors were measured on the day of renal transplantation. The Scr levels in the recipients were measured at postoperative 1, 3 and 12 months respectively. The estimated glomerular filtration rate (eGFR) was calculated. The correlation between the serum Klotho level of the donors and postoperative graft function of the recipients was analyzed. Results The cold ischemia time during renal transplantation was (649±245) min. The incidence rate of delayed graft function (DGF) was 26%. The incidence rate of acute rejection was 7%. In the elderly donors, the serum Klotho level was 537 (245-793) pg/mL and the Scr level was (164±62) μmol/L. At postoperative 1, 3 and 12 months, the Scr levels in the recipients were (136±47), (132±43) and (133±46) μmol/L, respectively. The corresponding eGFR was (52±20), (52±19) and (53±21) mL/(min?1.73m2), respectively. The serum Klotho level in the elderly donors was negatively correlated with the renal graft function at postoperative 1 month in the recipients (P < 0.05). The sensitivity and specificity of serum Klotho level in predicting the renal graft insufficiency at postoperative 1 month were 0.909 and 0.769. Conclusions The preoperative serum Klotho level in the elderly donors have predictive value for renal graft function in the recipients at postoperative 1 month.

Characteristics and risk factors analysis of infection after liver transplantation from donor liver of donation after citizen's death / 器官移植

Objective To investigate the characteristics and risk factors of infection after liver transplantation from donor liver of donation after citizen's death. Methods Clinical data of 68 recipients after liver transplantation from donor liver of donation after citizen's death were analyzed retrospectively. The recipients were divided into infection group (33 cases) and non-infection group (35 cases) according to the presence of infection after operation. Major infection characteristics of the 68 recipients after liver transplantation were summarized. Univariate analysis was conducted on the possible risk factors of infection after liver transplantation, and multivariate analysis was further conducted on the risk factors with statistical significance, so as to find out the independent risk factors. In addition, accuracy of predicting infection after liver transplantation was analyzed using receiver operating characteristic (ROC) curves. Results Thirty-three recipients were infected after liver transplantation, accounting for 49% of the total recipients with bacterial infection and fungal infection mainly. These recipients mainly presented pulmonary infection and abdominal cavity infection. Univariate analysis results showed that a total of 8 factors contributed to infection after liver transplantation from donor liver of organ donation, including the donors' open injury, recipients' preoperative hemoglobin level, platelet count, Child-Pugh classification of liver function, model for end-stage liver disease (MELD) score, intraoperative erythrocyte infusion, gamma-glutamyl transpeptidase (GGT) on day 1 after operation and postoperative stay time of intensive care unit (ICU) (all P<0.05). Multivariate Logistic regression results analysis showed that preoperative hemoglobin level <120 g/L and postoperative stay time of ICU >96 h were the independent risk factors of infection after liver transplantation from donor liver of organ donation (both P<0.05). Analysis results of ROC curves showed that preoperative hemoglobin level<114 g/L and postoperative stay time of ICU >102 h resulted in higher accuracy for predicting postoperative infection. Conclusions Infection after liver transplantation from donation after citizen's death presents high incidence, dominated by bacterial infection and fungal infection in lung and abdominal cavity. Low preoperative hemoglobin level and long postoperative stay time of ICU of recipients can increase the risk of infection after liver transplantation.

Diagnostic value of flow cytometry in postoperative infection after renal transplantation / 器官移植

Objective To assess the value of flow cytometry in the diagnosis of postoperative infection following renal transplantation. Methods According to postoperative imaging findings and laboratory examination outcomes, 51 recipients undergoing the first renal transplantation were divided into the bacteria (n=33), fungus (n=9) and BK virus (n=9) groups. Twenty-eight recipients with stable conditions after renal transplantation were assigned into the stable group. Flow cytometry was adopted to detect the percentage and absolute counting of lymphocyte subpopulation in the peripheral blood of recipients in each group. Renal function, percentage and absolute counting of lymphocyte subpopulation in the peripheral blood were statistically compared among different groups. Receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic value of the percentage and absolute counting of lymphocyte subpopulation in infectious diseases after renal transplantation. Results Compared with the stable group, the serum creatinine (Scr) and blood urea nitrogen (BUN) levels in the bacteria, fungus and BK virus groups were significantly up-regulated, respectively (P=0.035, 0.007, 0.024; 0.037, 0.006, 0.032). Compared with the stable group, the percentage of CD16+CD56+natural killer (NK) cells was significantly declined in the bacterial (P=0.036) and fungus groups (P=0.015), and the proportion of CD4+/CD8+T cells was dramatically decreased in the fungus group (P=0.004). Compared with the bacterial group, the percentage of CD3+CD8+T cells was significantly elevated (P=0.013 and 0.008), the proportion of CD3+CD4+T cells was considerably declined (P=0.003 and 0.010), and the percentage of CD4+/CD8+T cells was significantly declined (P=0.003 and 0.005) in the fungus and BK virus groups. Compared with the stable group, the quantity of CD3+T cells, CD3+CD8+T cells and CD16+CD56+NK cells was significantly declined in the bacterial, fungus and BK virus groups, respectively (P=0.025, 0.002, 0.003; 0.015, 0.005, 0.006; 0.001, 0.001, 0.031). In addition, the quantity of CD3+CD4+T cells was considerably decreased in the fungus and BK virus groups (P=0.001, 0.003). The quantity of CD19+B cells was significantly reduced in the BK virus group (P=0.019). Compared with the bacterial group, the quantity of CD3+CD4+T cells was considerably lower in the fungus group (P=0.023). ROC curve analysis revealed that the quantity of CD3+CD4+T cells [area under curve(AUC)=0.8492] and CD16+CD56+NK cells (AUC=0.8889) yielded relatively high accuracy in the diagnosis of fungal infection. The quantity of CD3+T cells (AUC=0.8472), CD3+CD4+T cells (AUC=0.8452) and CD19+B cells (AUC=0.8115) yielded relatively high accuracy in the diagnosis of BK virus infection. Conclusions Flow cytometry detection of the lymphocyte subpopulation in peripheral blood can evaluate the immune function of patients. Absolute counting of lymphocyte subpopulation can directly assess the degree of immunity. These two combined parameters provide guiding significance for the diagnosis and differential diagnosis of infectious diseases in recipients after renal transplantation.

Optimal Cutoff Points of Anthropometric Parameters to Identify High Coronary Heart Disease Risk in Korean Adults

Several published studies have reported the need to change the cutoff points of anthropometric indices for obesity. We therefore conducted a cross-sectional study to estimate anthropometric cutoff points predicting high coronary heart disease (CHD) risk in Korean adults. We analyzed the Korean National Health and Nutrition Examination Survey data from 2007 to 2010. A total of 21,399 subjects aged 20 to 79 yr were included in this study (9,204 men and 12,195 women). We calculated the 10-yr Framingham coronary heart disease risk score for all individuals. We then estimated receiver-operating characteristic (ROC) curves for body mass index (BMI), waist circumference, and waist-to-height ratio to predict a 10-yr CHD risk of 20% or more. For sensitivity analysis, we conducted the same analysis for a 10-yr CHD risk of 10% or more. For a CHD risk of 20% or more, the area under the curve of waist-to-height ratio was the highest, followed by waist circumference and BMI. The optimal cutoff points in men and women were 22.7 kg/m2 and 23.3 kg/m2 for BMI, 83.2 cm and 79.7 cm for waist circumference, and 0.50 and 0.52 for waist-to-height ratio, respectively. In sensitivity analysis, the results were the same as those reported above except for BMI in women. Our results support the re-classification of anthropometric indices and suggest the clinical use of waist-to-height ratio as a marker for obesity in Korean adults.

Using receiver operating characteristic curve analysis in detecting excess adiposity in 9-13-year old South African children / Uso del análisis de la curva de las características operativas del receptor (ROC) para detectar el exceso de adiposidad en niños Sudafricanos de 9 a 13 años de edad

OBJECTIVE: Little is known concerning the applicability of receiver operating characteristic (ROC) curve analysis in detecting excess adiposity in preadolescent South African children. Therefore, the purpose of this study was to evaluate the sensitivity and specificity of body mass index (BMI) and skinfold thickness:BMI (subcutaneous to overall fat) in detecting excess adiposity in preadolescent urban South African school children. METHODS: This was a cross-sectional survey of 1136 randomly selected children (548 boys and 588 girls) aged 9-13 years old in urban (Pretoria Central) South Africa. Body mass, stature, skinfolds (subscapular, triceps, supraspinale and biceps) and waist circumference were measured. Receiver operating characteristic curve analysis was used to assess the sensitivity and specificity of BMI, and log10 SF4:BMI to detect excess adiposity. Excess adiposity was defined as levels of log10 SF4 greater than the internally derived 85th percentile (log10 SF4 > 85th percentile). RESULTS: Compared to log10 SF4:BMI, BMI had a high specificity (0.88; 95% CI 0.84, 0.90). The log10 SF4:BMI identified excess adiposity with a sensitivity and specificity of 0.62 (95% CI 0.60, 0.67) and 0.68 (95% CI 0.64, 0.70), respectively. Besides, a decrease in overall misclassification with the use of log10 SF4:BMI instead of BMI at the 95th percentile (9.7% versus 27.1%) was observed. CONCLUSION: Similar to other studies, although with varying degrees, the present study confirms that log10 SF4:BMI at conventional cut-off points has a relatively high sensitivity and specificity in detecting excess adiposity, and therefore could be used to identify the excess adiposity in South African children. As such, defining obesity based on population-specific percentiles rather than using cut-off points derived from other geographical settings with contrasting levels of socio-economic development becomes imperative.

OBJETIVO: Poco se sabe acerca de las posibilidades de aplicación del análisis de la curva de las características operativas del receptor (ROC) para detectar el exceso de adiposidad en preadolescentes sudafricanos. Por consiguiente, el propósito de este estudio fue evaluar la sensibilidad y especificidad del índice de masa corporal, y grosor de los pliegues cutáneos:IMC (subcutáneo con respecto a la grasa general) a la hora de detectar el exceso de adiposidad en los escolares preadolescentes urbanos de Sudáfrica. MÉTODOS: Se realizó un estudio transversal de 1136 niños seleccionados de manera aleatoria (548 varones y 588 hembras) de 9 a 13 años de edad en la Sudáfrica urbana (Pretoria Central). Se midieron la masa corporal, la estatura, los pliegues cutáneos (subescapular, supraespinal, así como del tríceps y el bíceps) y la circunferencia de la cintura. Se hizo uso del análisis de la curva de las características operativas del receptor para evaluar la sensibilidad y especificidad del IMC, y el log10 PC4: IMC, a fin de detectar el exceso de adiposidad. El exceso de adiposidad fue definido en términos de la medida en que los niveles del log10 PC4 fueran mayores que el percentil 85 (log10 PC4 > percentil 85). RESULTADOS: Comparado con el log10 SF4:IMC, el IMC tenía una alta especificidad (0.88; 95% CI 0.84, 0.90). El log10 SF4:IMC identificó exceso de adiposidad con una sensibilidad y especificidad de 0.62 (95% CI 0.60, 0.67) y 0.68 (95% CI 0.64, 0.70), respectivamente. Además, una disminución en los errores de clasificación global con el uso del log10 SF4:IMC en lugar del IMC en el percentil 95 (9.7% frente a 27.1%) se observó. CONCLUSIÓN: Similar a otros estudios, aunque con diferencias de grados, el estudio presente confirma que el log10 SF4:IMC a ciertos puntos convencionales límites, posee una sensibilidad y una especificidad relativamente altas a la hora de detectar la adiposidad en exceso, y por consiguiente podría usarse para identificar el exceso de adiposidad en los niños sudafricanos. Siendo así, resulta imperativo definir la obesidad sobre la base de los percentiles específicos de la población, más bien que a partir del uso de puntos de corte derivados de otros sitios geográficos con niveles contrastantes de desarrollo económico.

Evaluation of Waist Circumference Cut-off Values as a Marker for Fatty Liver among Japanese Workers

OBJECTIVES: Metabolic syndrome has received attention as a risk factor for cardiovascular disease, with particular importance attached to visceral fat accumulation, which is associated with lifestyle-related diseases and is strongly correlated with waist circumference. In this study, our aim is to propose waist circumference cut-off values that can be used as a marker for fatty liver based on a sample of workers receiving health checkups in Japan. METHODS: This study was conducted in a total of 21,866 workers who underwent periodic health checkups between January 2007 and December 2007. The mean age of the subjects was 47.4 years for men (standard deviation [SD]: 8.0) and 44.7 years for women (SD: 6.9). Evaluation included abdominal ultrasound and measurement of waist circumference, body mass index, fasting blood glucose, triglycerides, high-density lipoprotein cholesterol, and blood pressure. RESULTS: Based on receiver operating characteristic curve analysis, the optimal waist circumference cut-off values were shown as 85.0 cm (sensitivity 0.72, specificity 0.69) for men and 80.0 cm (sensitivity 0.75, specificity 0.78) for women. CONCLUSION: Abdominal ultrasound is the most efficient means of diagnosing fatty liver, but this examination seldom occurs because the test is not routinely performed at workers' health checkups. In people found to have a high risk of fatty liver, recommendations can be made for abdominal ultrasound based on the waist circumference cut-off values obtained in this study. That is, waist circumference can be used in high risk individuals as an effective marker for early detection of fatty liver.

Evaluation of Waist Circumference Cut-off Values as a Marker for Fatty Liver among Japanese Workers

OBJECTIVES: Metabolic syndrome has received attention as a risk factor for cardiovascular disease, with particular importance attached to visceral fat accumulation, which is associated with lifestyle-related diseases and is strongly correlated with waist circumference. In this study, our aim is to propose waist circumference cut-off values that can be used as a marker for fatty liver based on a sample of workers receiving health checkups in Japan. METHODS: This study was conducted in a total of 21,866 workers who underwent periodic health checkups between January 2007 and December 2007. The mean age of the subjects was 47.4 years for men (standard deviation [SD]: 8.0) and 44.7 years for women (SD: 6.9). Evaluation included abdominal ultrasound and measurement of waist circumference, body mass index, fasting blood glucose, triglycerides, high-density lipoprotein cholesterol, and blood pressure. RESULTS: Based on receiver operating characteristic curve analysis, the optimal waist circumference cut-off values were shown as 85.0 cm (sensitivity 0.72, specificity 0.69) for men and 80.0 cm (sensitivity 0.75, specificity 0.78) for women. CONCLUSION: Abdominal ultrasound is the most efficient means of diagnosing fatty liver, but this examination seldom occurs because the test is not routinely performed at workers' health checkups. In people found to have a high risk of fatty liver, recommendations can be made for abdominal ultrasound based on the waist circumference cut-off values obtained in this study. That is, waist circumference can be used in high risk individuals as an effective marker for early detection of fatty liver.

REFERENCE INTERVAL OF MAXIMAL OXYGEN UPTAKE (VO₂max) AS ONE OF THE DETERMINANTS OF HEALTH-RELATED PHYSICAL FITNESS IN JAPAN / 体力科学

Maximal oxygen uptake (VO₂max) is an important determinant of health-related physical fitness. In 2006, the Japan Ministry of Health, Labour and Welfare (JMHLW) officially declared a standard reference value and reference interval of VO₂max. However, these values were established on the basis of a systematic review of reports published in Western countries and were not based on actual VO₂max data of the Japanese population. Therefore, we conducted a study entitled “The study on a minimum zone of VO₂max as one of the determinants of health-related physical fitness in Japan” from 2004 to 2006 as a project of the Japanese Society of Physical Fitness and Sports Medicine (JSPFSM). In addition, we collected published VO₂max data of the Japanese population from the JSPEFM website. In the present study, we attempted to determine the reference interval of VO₂max with regard to age, gender, and different methods of exercise. Further, we established a cut-off value of VO₂max for determining metabolic syndrome (MS).1. Reference interval of VO₂maxFor both men and women, 325 and 364 values for the treadmill exercise, and 1175 and 2178 values for the cycle ergometer exercise, respectively, were collected. This data revealed a balanced distribution of VO₂max with regard to age. Data that satisfied the VO₂max criterion were used for the analysis. These data were regressed to age on gender and methods of exercise. The percentage of VO₂max was calculated using the following equation: %VO₂max = measured VO₂max × 100/age-estimated VO₂max. The iterative truncation method was used to calculate the reference interval of VO₂max (70%∼130% VO₂max) from the crude data of %VO₂max, and then converted to actual VO₂max. Thus, the reference interval of VO₂max for healthy Japanese was determined with regard to age, gender, and different methods of exercise.2. Cut-off value of VO₂max for determining MSUsing the VO₂max data of subjects with body mass index (BMI) of ≧25kg/m² and ≧2 MS risk factors, and the data of subjects with normal BMI without any risk factors, we calculated sensitivity and specificity. The cut-off value was determined using the receiver operating characteristic curve. This cut-off value was defined as the critical value of VO₂max that should be maintained to avoid MS and remain healthy.

Receiver Operating Characteristic (ROC) Curve: Practical Review for Radiologists

The receiver operating characteristic (ROC) curve, which is defined as a plot of test sensitivity as the y coordinate versus its 1-specificity or false positive rate (FPR) as the x coordinate, is an effective method of evaluating the performance of diagnostic tests. The purpose of this article is to provide a nonmathematical introduction to ROC analysis. Important concepts involved in the correct use and interpretation of this analysis, such as smooth and empirical ROC curves, parametric and nonparametric methods, the area under the ROC curve and its 95% confidence interval, the sensitivity at a particular FPR, and the use of a partial area under the ROC curve are discussed. Various considerations concerning the collection of data in radiological ROC studies are briefly discussed. An introduction to the software frequently used for performing ROC analyses is also presented.

Critical and desirable levels of health-related physical fitness (HRPF) in men-Established levels based on health examination and risk factors caused by lifestyle habits- / 体力科学

This study tried to establish both critical and desirable levels of health-related physical fitness (HRPF) including muscle strength (relative grip strength), flexibility and estimated VO<SUB>2</SUB>max. Subjects were 3102 males aged 20 to 59 years. Four batteries of health index score (HIS-A-D) were made based on health examinations and lifestyle habits. Subjects who had 0 to 1 points were defined as healthy individuals, and subjects who had more than 3 or 4 points were defined as unhealthy. Receiver-operating characteristic (ROC) curves were drawn by HRPF test in each battery of HIS. The HIS-B was selected as the most valid battery of HIS. Sensitivity, specificity and the Youden index were calculated using cut-off values which were mean values of each HRPF test measurement in each group who had 0, 1, 2, 3 and>4 points in HIS-B. The critical levels were defined the highest specificity and/or Youden index in each HRPF test. There were seen in groups having > 4 points. The desirable levels were defined as the HRPF test levels in healthy individuals who had 0 to 1 points in HIS-B. The critical and desirable levels of VO<SUB>2</SUB>max were 41.8 and 50.2 at 20y, 40.9 and 46.2 at 30y, 40.0 and 46.2 at 40y, and 37.8 and 45.5 ml/kg/min at 50y, respectively. The levels of other HRPF test were also calculated in the present study. Exercise guidance after health check-ups should be done to attain desirable levels rather than to just maintain critical levels of HRPF.