Limits...
Novel equations better predict lung age: a retrospective analysis using two cohorts of participants with medical check-up examinations in Japan.

Ishida Y, Ichikawa YE, Fukakusa M, Kawatsu A, Masuda K - NPJ Prim Care Respir Med (2015)

Bottom Line: As a result of the linear regression analysis for forced expiratory volume in 1 s (FEV1), spirometric variables using forced vital capacity (FVC) improved the adjusted R(2) values to greater than 0.8.On the basis of the scatter plots between chronological age and SDL age, the best model included the equations using FEV1 and %FVC in females and males (R(2)=0.66 and 0.55, respectively), which was confirmed by the validation cohort.This study produced novel SDL age equations for Japanese adults using data from a large number of healthy never-smokers with both normal spirometric measurements and BMIs.

View Article: PubMed Central - PubMed

Affiliation: Pediatric Medical Center, Ehime Prefectural Central Hospital, Ehime, Japan.

ABSTRACT

Background: The lung age equations developed by the Japanese Respiratory Society encounter several problems when being applied in a clinical setting.

Aims: To establish novel spirometry-derived lung age (SDL age) equations using data from a large number of Japanese healthy never-smokers with normal spirometric measurements and normal body mass indices (BMIs).

Methods: The participants had undergone medical check-ups at the Center for Preventive Medicine of St Luke's International Hospital between 2004 and 2012. A total of 15,238 Japanese participants (5,499 males and 9,739 females) were chosen for the discovery cohort. The other independent 2,079 individuals were selected for the validation cohort. The original method of Morris and Temple was applied to the discovery cohort.

Results: As a result of the linear regression analysis for forced expiratory volume in 1 s (FEV1), spirometric variables using forced vital capacity (FVC) improved the adjusted R(2) values to greater than 0.8. On the basis of the scatter plots between chronological age and SDL age, the best model included the equations using FEV1 and %FVC in females and males (R(2)=0.66 and 0.55, respectively), which was confirmed by the validation cohort. The following equations were developed: SDL age (females)=0.84×%FVC+50.2-40×FEV1 (l) and SDL age (males)=1.00×%FVC+50.7-33.3×FEV1 (l).

Conclusions: This study produced novel SDL age equations for Japanese adults using data from a large number of healthy never-smokers with both normal spirometric measurements and BMIs.

Show MeSH

Related in: MedlinePlus

The scatter plots between chronological age (years) and SDL age (years) in non-smokers with normal spirometric measurements and normal BMI in Group 2. Scatter plots between chronological age and SDL age in never/non-smokers with normal spirometric measurements and BMIs in Group 2. SDL age was determined in females and males according to the JRS equations (a and b, respectively), model 2 equations (c and d, respectively) and model 3 equations (e and f, respectively). The lines of best fit for SDL age (y) against chronological age (x) are expressed by solid lines. Dotted lines indicate identity lines (y=x).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4373493&req=5

fig4: The scatter plots between chronological age (years) and SDL age (years) in non-smokers with normal spirometric measurements and normal BMI in Group 2. Scatter plots between chronological age and SDL age in never/non-smokers with normal spirometric measurements and BMIs in Group 2. SDL age was determined in females and males according to the JRS equations (a and b, respectively), model 2 equations (c and d, respectively) and model 3 equations (e and f, respectively). The lines of best fit for SDL age (y) against chronological age (x) are expressed by solid lines. Dotted lines indicate identity lines (y=x).

Mentions: We conducted the validation study using an independent cohort (Group 2). The scatter plots of the relationships between chronological age and SDL age in never-smokers with normal spirometric measurements and normal BMIs in Group 2 are shown in Figure 4. We compared model 2 and model 3 with the original JRS model. Similar to Group 1, model 3 was considered the best model in both females and males because of the values of R2. However, the slopes of model 2 and model 3 were from 0.73 to 0.80 (there were some discrepancies to 1). The box and whisker plots of the lung age deficit according to smoking status in Group 2 are shown in Supplementary Figure 3. Similar to Group 1, the lung age deficit values distributed more widely in the JRS method compared with model 3.


Novel equations better predict lung age: a retrospective analysis using two cohorts of participants with medical check-up examinations in Japan.

Ishida Y, Ichikawa YE, Fukakusa M, Kawatsu A, Masuda K - NPJ Prim Care Respir Med (2015)

The scatter plots between chronological age (years) and SDL age (years) in non-smokers with normal spirometric measurements and normal BMI in Group 2. Scatter plots between chronological age and SDL age in never/non-smokers with normal spirometric measurements and BMIs in Group 2. SDL age was determined in females and males according to the JRS equations (a and b, respectively), model 2 equations (c and d, respectively) and model 3 equations (e and f, respectively). The lines of best fit for SDL age (y) against chronological age (x) are expressed by solid lines. Dotted lines indicate identity lines (y=x).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4373493&req=5

fig4: The scatter plots between chronological age (years) and SDL age (years) in non-smokers with normal spirometric measurements and normal BMI in Group 2. Scatter plots between chronological age and SDL age in never/non-smokers with normal spirometric measurements and BMIs in Group 2. SDL age was determined in females and males according to the JRS equations (a and b, respectively), model 2 equations (c and d, respectively) and model 3 equations (e and f, respectively). The lines of best fit for SDL age (y) against chronological age (x) are expressed by solid lines. Dotted lines indicate identity lines (y=x).
Mentions: We conducted the validation study using an independent cohort (Group 2). The scatter plots of the relationships between chronological age and SDL age in never-smokers with normal spirometric measurements and normal BMIs in Group 2 are shown in Figure 4. We compared model 2 and model 3 with the original JRS model. Similar to Group 1, model 3 was considered the best model in both females and males because of the values of R2. However, the slopes of model 2 and model 3 were from 0.73 to 0.80 (there were some discrepancies to 1). The box and whisker plots of the lung age deficit according to smoking status in Group 2 are shown in Supplementary Figure 3. Similar to Group 1, the lung age deficit values distributed more widely in the JRS method compared with model 3.

Bottom Line: As a result of the linear regression analysis for forced expiratory volume in 1 s (FEV1), spirometric variables using forced vital capacity (FVC) improved the adjusted R(2) values to greater than 0.8.On the basis of the scatter plots between chronological age and SDL age, the best model included the equations using FEV1 and %FVC in females and males (R(2)=0.66 and 0.55, respectively), which was confirmed by the validation cohort.This study produced novel SDL age equations for Japanese adults using data from a large number of healthy never-smokers with both normal spirometric measurements and BMIs.

View Article: PubMed Central - PubMed

Affiliation: Pediatric Medical Center, Ehime Prefectural Central Hospital, Ehime, Japan.

ABSTRACT

Background: The lung age equations developed by the Japanese Respiratory Society encounter several problems when being applied in a clinical setting.

Aims: To establish novel spirometry-derived lung age (SDL age) equations using data from a large number of Japanese healthy never-smokers with normal spirometric measurements and normal body mass indices (BMIs).

Methods: The participants had undergone medical check-ups at the Center for Preventive Medicine of St Luke's International Hospital between 2004 and 2012. A total of 15,238 Japanese participants (5,499 males and 9,739 females) were chosen for the discovery cohort. The other independent 2,079 individuals were selected for the validation cohort. The original method of Morris and Temple was applied to the discovery cohort.

Results: As a result of the linear regression analysis for forced expiratory volume in 1 s (FEV1), spirometric variables using forced vital capacity (FVC) improved the adjusted R(2) values to greater than 0.8. On the basis of the scatter plots between chronological age and SDL age, the best model included the equations using FEV1 and %FVC in females and males (R(2)=0.66 and 0.55, respectively), which was confirmed by the validation cohort. The following equations were developed: SDL age (females)=0.84×%FVC+50.2-40×FEV1 (l) and SDL age (males)=1.00×%FVC+50.7-33.3×FEV1 (l).

Conclusions: This study produced novel SDL age equations for Japanese adults using data from a large number of healthy never-smokers with both normal spirometric measurements and BMIs.

Show MeSH
Related in: MedlinePlus