Table 4

Rapid decline in lung function between CARDIA Y10 and Y20 (mean ages of 35–45 years) is temporally associated with incident metabolic syndrome at Y20 or Y25 (mean age of 45 or 50 years)

%Incident metabolic syndromeUnadjusted modelAdjusted model*
OR (95% CI)OR (95% CI)
Rapid FEV1 decline (n=754)26.91.58 (1.29 to 1.95) 
p<0.001
1.56 (1.26 to 1.94) 
p<0.001
Non-rapid FEV1 decline (n=1504)18.9
Rapid FVC decline (n=753)30.02.04 (1.67 to 2.50) 
p<0.001
2.10 (1.69 to 2.61) 
p<0.001
Non-rapid FVC decline (n=1505)17.3
  • Note 1: The adjusted models* were rerun in exploratory analyses set 1, including additional covariates. For separate analyses using rapid decline in FEV1 and FVC as outcomes, additional adjustment for BMI, HTN and family history of diabetes mellitus, at CARDIA Y10, did not change the results with OR 1.54 (1.22, 1.95) p<0.001 for rapid decline in FEV1 and OR 1.85 (1.46, 2.34) p<0.001 for rapid decline in FVC. Additional adjustment for current smoking status and pack-years at Y15 and at Y20 to the exploratory model did not change the results; p<0.001 for analyses involving both predictors.

  • Note 2: The association between rapid decline in FEV1 and incident metabolic syndrome was no longer significant after adjustment for intrathoracic visceral adiposity OR 1.16 (0.90, 1.50) p=0.26. The association remained unchanged after adjustment in separate models for the other CT adiposity measures. For rapid decline in FVC, similar results were seen as with FEV1. The association was attenuated but remained statistically significant after adjustment for intrathoracic visceral adiposity OR 1.50 (1.16, 1.93) p=0.002. The association remained unchanged after adjustment in separate models for the other CT adiposity measures.

  • Note 3: There was no significant interaction between sex and rapid lung function decline on the metabolic syndrome (unadjusted interaction p=0.44 and 0.80 for rapid FEV1 decline and rapid FVC decline, respectively).

  • Note 4: Rapid decline was measured between CARDIA Y10 and Y20 as the tertile with the greatest decline in lung function and was compared with the group including subjects in the bottom two tertiles. Rapid FEV1 and FVC decline between CARDIA Y10 and Y20 was defined by 44.2 mL/year and 48.1 mL/year, respectively. Analyses with decline in lung function as continuous, and ternary variables showed similar results and are presented in tables E-IV and E-V, respectively, in the online data supplementary file 1.

  • *Adjusted models included standard covariates, all measured at Y10.

  • BMI, body mass index; CARDIA, Coronary Artery Risk Development in Young Adults; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; HDL, high-density lipoprotein.