Metabolic and Lipid Biomarkers as Correlates of Pulmonary Function in Middle-Aged Non-Smokers

Authors

Carson Greenwood, Tarleton State UniversityFollow
Mandy E. Parra, Tarleton State UniversityFollow
Micheal Luera, Tarleton State University, StephenvilleFollow
Olivia Russell, Tarleton State UniversityFollow
Leroy BoldenFollow
Craig Hermans, Tarleton State UniversityFollow
Jeffrey Forsse, Baylor University
Tomas J. Chapman-Lopez, Tarleton State UniversityFollow

Abstract

Pulmonary function testing is widely used to assess respiratory health and detect early functional decline. While relationships between lung function and systemic biomarkers have been described in clinical populations, limited data exist examining these associations in metabolically healthy adults without diagnosed chronic disease. PURPOSE: To examine the relationships between blood-based metabolic, lipid, renal, and hematologic biomarkers and pulmonary function in middle-aged, metabolically healthy adults. METHODS: Participants were recruited through a university-based health outreach program conducted between 2020 and 2024. Inclusion criteria included participants aged between 40 – 65 years, non-smoking status, and absence of diagnosed pulmonary, cardiovascular, renal, or metabolic disease. Eighty-nine adults [Females: n = 52 (52.7 ± 8.1years), Males: n = 37 (50.2 ± 6.3y)] completed standardized fasting blood collection (metabolic, lipid, and complete blood cell count) and spirometry testing. Pulmonary outcomes included forced expiratory volume in one second (FEV₁), forced vital capacity (FVC), and the FEV₁/FVC ratio. Pearson correlations assessed bivariate relationships, and multiple linear regression identified independent predictors of FEV₁ adjusting for age, sex, and BMI. RESULTS: Males exhibited higher pulmonary volumes than females (FEV₁: 3.60 ± 0.75L vs. 2.64 ± 0.63L; FVC: 4.58 ± 0.79L vs. 3.24 ± 0.65L), while FEV₁/FVC ratios were similar between sexes. FEV₁ was positively correlated with creatinine (r = 0.535, p < .001), RBC count (r = 0.419, p < .001), hemoglobin (r = 0.430, p < .001), and hematocrit (r = 0.412, p < .001), and inversely correlated with HDL-cholesterol (r = –0.364, p < .001). Similar associations were observed for FVC. No biomarkers were significantly associated with FEV₁/FVC. In multivariable regression, age (B = –0.032 L/year, p = .001) and sex (B = 0.701L, p < .001) were independent predictors of FEV₁, while blood biomarkers were not independently associated after adjustment. The model explained 44.5% of FEV₁ variance (adjusted R² = 0.412). CONCLUSION: Several blood biomarkers are associated with lung volumes in unadjusted analyses; however, demographic factors primarily explain pulmonary function variability in metabolically healthy middle-aged adults. These findings suggest that systemic biomarker–lung volume relationships reflect underlying physiologic differences rather than early airway impairment in healthy populations.

Recommended Citation

Greenwood, Carson; Parra, Mandy E.; Luera, Micheal; Russell, Olivia; Bolden, Leroy; Hermans, Craig; Forsse, Jeffrey; and Chapman-Lopez, Tomas J. (2026) "Metabolic and Lipid Biomarkers as Correlates of Pulmonary Function in Middle-Aged Non-Smokers," International Journal of Exercise Science: Conference Proceedings: Vol. 2: Iss. 18, Article 160.
Available at: https://digitalcommons.wku.edu/ijesab/vol2/iss18/160