Being Fit May Slow Lung Function Decline as We Age

Newswise — ATS 2016, SAN FRANCISCO – Being fit may reduce the decline in lung function that occurs as we grow older, according to research presented at the ATS 2016 International Conference.

“While everyone’s lung function declines with age, the actual trajectory of this decline varies among individuals, “ said Lillian Benck, MD, a medical resident at Northwestern University Feinberg School of Medicine, Chicago, Illinois, and study lead investigator. “What is less known is, beyond smoking, what factors affect this rate of decline.”

Dr. Benck added that even though the majority of people will not develop lung disease in their lifetime, “declining lung function is known to increase overall morbidity and mortality even in the absence of overt pulmonary disease.”

Dr. Benck and her colleagues analyzed data from the National Heart, Lung, and Blood Institute’s CARDIA (Coronary Risk Development in Young Adults Study), which began in 1985-86 with 5,115 healthy black and white men and women, aged 18-30. The study has measured participant’s cardiopulmonary fitness periodically over 20 years using a graded treadmill test. At the beginning of the study and at each follow-up assessment, pulmonary function (PF) was also assessed by measuring forced expiratory volume in one second (FEV1) and forced vital capacity (FVC).

After adjusting for age, smoking, body mass index and change in BMI, the association between fitness and lung function remained statistically significant.

Researchers found that participants:• in the top quartile of baseline fitness experienced the least annual decline in PF.

• with the greatest decline in fitness experienced the greatest decline in FEV1and PF over 20 years.

• with sustained or improved fitness experienced the least decline in PF over 20 years.

Dr. Benck said that the last finding is noteworthy because it indicates that fitness matters, not just at a single point in time but over many years. “Fitness early in life and at middle age appears to attenuate this natural decline,” she said, noting that the benefit of fitness was even seen among smokers.

Because it is an observational study, researchers cannot claim cause and effect. However, they noted several important strengths, including a large study population and long-term follow-up and objective measurements of fitness and lung health.

Dr. Benck said that CARDIA will continue to follow participants and may eventually provide insights into whether fitness not only preserves lung function, but also reduces the risk of developing lung disease.Contact for study: Lillian Benck, MD, [email protected]

Abstract 10510Sustained or Relative Increases in Cardiopulmonary Fitness Are Associated with Preserved Lung Health from Young Adulthood to Middle AgeL. Benck1, M. Cuttica1, L. Colangelo1, S. Sidney2, M.T. Dransfield3, C. Lewis4, D.R. Jacobs, Jr.5, N. Zhu6, D. Mannino7, M. Carnethon1, K. Liu1, R.Kalhan11Northwestern University Feinberg School of Medicine - Chicago, IL/US, 2Kaiser Permanente - Oakland, CA/US, 3University of Alabama at Birmingham - Birmingham, AL/US, 4University of Alabama at Birmingham - Birmingham/US, 5University of Minnesota - Minneapolis, MN/US, 6DEPT OF INTERNAL MED MILLS - Bronx, NY/US, 7University of Kentucky - Lexington, KY/US

Rationale: Beyond smoking there are limited data on factors associated with changes in lung health. We evaluated whether cardiopulmonaryfitness is associated with preservation of lung health over time in acohort of healthy young adults. We hypothesized that both maintainingand improving to a relatively high-level of fitness is associated with lessloss of lung health compared to maintaining or worsening to a low-levelof fitness independent of obesity and smoking.

Methods: The CARDIA study was initiated in 1985 among healthy 18 to30 year old black and white individuals. Cardiopulmonary fitness wasmeasured by symptom-limited, graded treadmill test at years 0 and 20.Cardiopulmonary fitness was divided into race-sex specific quartiles bybaseline fitness (N=3330) and longitudinal fitness change (N=2733).Sustained higher fitness was defined as being above the race-sex specificmedian at years 0 and 20, sustained lower fitness as below the median atyears 0 and 20, relatively increased fitness as below the median at year0, above at year 20, relatively decreased fitness as above the median atyear 0, below at year 20. Multivariable linear regression was used todetermine year 20 FVC and FEV1 and decline in FVC and FEV1 from peakto year 20 across baseline fitness quartiles and longitudinal fitnesschange groups adjusting for age, race-sex group, smoking, BMI, and BMIchange.

Results: Participants in the highest quartile of baseline fitness hadsignificantly less decline in FVC compared to individuals in the first (535mL vs 574 mL; p=0.02) and second (535 mL vs. 562 mL; p=0.04)quartiles. Participants with sustained higher fitness had significantly lessdecline in lung function than those with sustained lower fitness (FEV1:539 mL vs. 626 mL; p<0.001; FVC: 477 mL vs. 580 mL;p<0.001) andrelatively decreased fitness (FEV1: 539 mL vs. 654 mL; p<0.001; FVC:477 mL vs. 615 mL; p<0.001). Participants with relatively increasedfitness had significantly less decline in lung function compared tosustained lower fitness (FEV1: 533 mL vs. 626 ml; p<0.001 and FVC:473 mL vs. 580 mL; p<0.001), and relatively decreased fitness (FEV1:533 mL vs. 654 mL; p<0.001; FVC: 473 mL vs 615 mL; p<0.001).

Conclusion: Greater cardiopulmonary fitness in young adulthood andachieving relatively increased level of fitness from young adulthood tomiddle age are associated with less decline in pulmonary function overtime, suggesting an association with preservation of lung healthindependent of BMI and smoking.