Hisamitsu Omori

Emphysema detected by lung cancer screening with low-dose spiral CT: Prevalence, and correlation with smoking habits and pulmonary function in Japanese male subjects

Objective:  Screening with low‐dose spiral CT is a promising new tool for early lung cancer detection. A study was undertaken to assess the prevalence of emphysema detected by CT screening, and to assess the correlation between the extent of emphysema and the severity defined according to the recently published Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria.

Reference values for spirometry, including vital capacity, in Japanese adults calculated with the LMS method and compared with previous values

BACKGROUND Reference values for lung function tests should be periodically updated because of birth cohort effects and improved technology. This study updates the spirometric reference values, including vital capacity (VC), for Japanese adults and compares the new reference values with previous Japanese reference values. METHODS Spirometric data from healthy non-smokers (20,341 individuals aged 17-95 years, 67% females) were collected from 12 centers across Japan, and reference equations were derived using the LMS method. This method incorporates modeling skewness (lambda: L), mean (mu: M), and coefficient of variation (sigma: S), which are functions of sex, age, and height. In addition, the age-specific lower limits of normal (LLN) were calculated. RESULTS Spirometric reference values for the 17-95-year age range and the age-dependent LLN for Japanese adults were derived. The new reference values for FEV(1) in males are smaller, while those for VC and FVC in middle age and elderly males and those for FEV(1), VC, and FVC in females are larger than the previous values. The LLN of the FEV(1)/FVC for females is larger than previous values. The FVC is significantly smaller than the VC in the elderly. CONCLUSIONS The new reference values faithfully reflect spirometric indices and provide an age-specific LLN for the 17-95-year age range, enabling improved diagnostic accuracy. Compared with previous prediction equations, they more accurately reflect the transition in pulmonary function during young adulthood. In elderly subjects, the FVC reference values are not interchangeable with the VC values.

Effect of smoking on FEV1 decline in a cross‐sectional and longitudinal study of a large cohort of Japanese males

Objective:  The effects of cigarette smoking and smoking cessation on age‐related pulmonary function decline was assessed in both cross‐sectional and longitudinal studies.

Secular changes in relative leg length confound height-based spirometric reference values.

BACKGROUND Most but not all data from different ethnic groups fit the Global Lung Function Initiative (GLI) spirometric reference model. This study investigates to what extent discrepancies are caused by secular changes in body proportions. METHODS FEV1 and FVC from 20,336 healthy Japanese subjects (13,492 women) aged 17 to 95 years were compared with GLI-2012 reference values for Europeans. Data on the sitting height/standing height ratio (Cormic index) in 17-year-old students, collected from 1949 to 2012 in successive birth cohorts, were used to assess secular changes in body frame. The cohort-specific Cormic index was used to assess how variation in body frame affected pulmonary function. RESULTS FEV1 and FVC were lower than GLI-2012 reference values, with values progressively falling until age 35 to 40 years and then rising to European levels in the elderly. The Cormic index rose until 1942, then fell, with a nadir in the 1970s, before rising again until 1995. Nearly one-half of the spirometric variability from predicted values could be explained by differences in the Cormic index between birth cohorts. CONCLUSIONS In low-income countries, improving health conditions are likely to drive increases in height and changes in relative leg length similar to those observed in Japan and, thus, to a change in body frame. This implies that height-based prediction equations for such populations will need to be periodically updated.

Computed-tomography findings of emphysema: correlation with spirometric values.

Purpose of review There is increasing interest in using multichannel computed-tomography scanning in the characterization of subjects with chronic obstructive pulmonary disease. Three distinct components – emphysema, large-airway inflammation and small-airway abnormality – have been evaluated using qualitative and quantitative approaches. Here we highlight computed-tomography findings of chronic obstructive pulmonary disease and correlation with spirometric values. Recent findings A considerable percentage of the subjects with emphysema detected by computed-tomography screening had normal spirometry. Severity of emphysema varies widely, even with same disease stage in chronic obstructive pulmonary disease. Studies of the relationship between high-resolution computed-tomography lung-attenuation measurements acquired under spirometric control of inspiratory and expiratory lung volume and pulmonary function showed that inspiratory measurements assess the extent of emphysema and that expiratory measurements reflect airflow limitation and air trapping. The evaluation using three-dimensional computed tomography demonstrates that airflow limitation is more closely related to the dimensions of small airways than large airways. Summary Volumetric computed-tomography scans allow diagnosis and quantification of the individual small airway and emphysema phenotypes present in people with chronic obstructive pulmonary disease. New computed-tomography scanning techniques should provide new insights into further understanding of the heterogeneity of chronic obstructive pulmonary disease.

Correlation of C-reactive protein with disease severity in CT diagnosed emphysema

Background and objective:  Recent studies suggest that CRP levels are related to airflow obstruction. However, limited data exist on the relevance of CRP levels in individuals with or without emphysema. The aim of this study was to assess the relationship between the extent of emphysema, COPD severity and serum CRP levels.

Development of the Psychiatric Nurse Job Stressor Scale (PNJSS)

Aims:  The aim of the present study was to develop a tool, the Psychiatric Nurse Job Stressor Scale (PNJSS), for measuring the stress of psychiatric nurses, and to evaluate the reliability and validity of the PNJSS.

A Large Cohort Study Concerning Age-Dependent Impacts of Anthropometric Variables on Spirometric Parameters in Nonsmoking Healthy Adults

Backgrounds Although height (H) has been considered the principal anthropometric variable governing lung function, the age-dependent differences in its influences on determining spirometric parameters (SPs) have not been conclusively investigated. Moreover, there has been no study centered on age-dependent effects of other anthropometric variables, including body weight (BW) and body fat mass (BFM) on SPs. In addition, the age-dependent influences of these anthropometric variables are anticipated to differ quantitatively between male and female participants. Methods A total of 16,919 nonsmoking healthy Japanese adults (men: 6,116, women: 10,803) were partitioned into six groups stratified by gender and age at intervals of 20-years: young-, middle-, and advanced-age groups of either gender. Using a model in which a SP was described by a logarithmic additive function of age, H, BW, and BFM, we determined the partial regression coefficients of the respective anthropometric variables to predict the reference means of SPs, including FVC, FEV1, FEV1/FVC, PEF, FEF50, and FEF75, in the six groups. Results/Discussion Although the impact of H on FVC and FEV1 was relatively homogeneous irrespective of gender and age, its homogeneity faded for flow parameters, particularly in the female middle- and advanced-age groups, indicating that the age-dependent contribution of H to SPs was enhanced more in women. The impact of BW on SPs differed depending on age, and this effect was also more conspicuous for female participants. H and BW generally exerted positive effects on SPs, whereas BFM had negative effects. Opposite effects of BW and BFM were observed in the female middle-age group in particular. Conclusions The effects of anthropometric variables on spirometric parameters are highly age-dependent, particularly in women, leading to the conclusion that the assumption of age-independent, constant partial regression coefficients of anthropometric variables while predicting the reference mean of a certain spirometric parameter may result in substantial errors.

Novel regression equations predicting lung age from varied spirometric parameters

Although lung age calculated backward from regression formulas constructed for FEV(1) estimation is widely used, it possesses a couple of faults. We developed novel equations predicting lung age from varied spirometric parameters (spirometry-derived lung age (SDL-age)). Applying multiple regression analysis, equations predicting SDL-age were invented using data from 8015 never-smokers with normal spirometry (group I). Validation was made based on data from 6398 never-smokers with normal spirometry (group II). Equations were further applied for 446 subjects with airflow limitation. FEV(1), FEV(1)/FVC, FEF(50), and PEF were selected as explanatory variables for reference value of SDL-age. Normal limits of difference between SDL-age and chronological-age were ± 13.4 years in the male and ± 15.0 years in the female. Established equations predicted SDL-age of group II. SDL-age was older than chronological-age only in subjects with severe airflow limitation. Novel regression equations allowing prediction of reference value of SDL-age and normal limits of difference between SDL-age and chronological-age were elaborated in both genders.

Association between Airflow Limitation Severity and Arterial Stiffness as Determined by the Brachial-Ankle Pulse Wave Velocity: A Cross-Sectional Study

Objective Chronic obstructive pulmonary disease (COPD) is often associated with concomitant systemic manifestations and comorbidities, such as cardiovascular disease. There are limited data regarding airflow limitation (AL) and atherosclerosis in Japanese patients, and the potential association between AL and arterial stiffness has not yet been investigated in Japanese patients. Therefore, the purpose of this study was to investigate the association between AL severity and arterial stiffness using the brachial-ankle pulse wave velocity (baPWV). Methods This cross-sectional study included 1,356 subjects aged 40-79 years without clinical cardiovascular diseases who underwent a comprehensive health screening that included spirometry, the baPWV measurement, and blood sampling during medical check-ups in 2009 at the Japanese Red Cross Kumamoto Health Care Center. AL was defined in accordance with the Global Initiative for COPD criteria (forced expiratory volume in one second / forced vital capacity of < 0.7). A cut-off baPWV value of >1,400 cm/s was used for risk prediction and screening. Results The average baPWV (SD) results were 1,578.0 (317.9), 1,647.3 (374.4), and 1,747.3 (320.1) cm/s in the patients with a normal pulmonary function, mild AL, and moderate-to-severe AL, respectively (p< 0.001). Using logistic regression models adjusted for the age, body mass index, smoking status, hypersensitive C-reactive protein levels, hypertension, hyperglycemia, and dyslipidemia, an increased baPWV (>1,400 cm/s) was significantly associated with moderate-to-severe AL compared with a normal pulmonary function (odds ratio=2.76; 95% confidence intervals, 1.37-5.55; p=0.004). Conclusion Our results indicated an association between AL and increased arterial stiffness. Arterial stiffness may therefore worsen with an increase in the severity of AL.