. Author manuscript; available in PMC: 2011 Jul 22.

Published in final edited form as: N Engl J Med. 2010 Jul 7;363(4):321–330. doi: 10.1056/NEJMoa0907897

Table 3.

Associations between Lung Function and Covariates of Ancestry-Based Models among Participants in the CARDIA Study, According to Sex.^*

Covariate	Men (N = 309)			Women (N = 468)
	FEV₁	FVC	FEV₁:FVC	FEV₁	FVC	FEV₁:FVC
	milliliters		FEV₁:FVC	milliliters		FEV₁:FVC
Intercept^†	3885.6	4763.9	81.8	2892.0	3368.4	86.1
Age (per yr)^‡	3.75	20.57	−0.29	−9.55	0.23	−0.31
African ancestry (per percentage point)^§	−8.14	−12.12	0.04	−5.54	−5.41	−0.03
Lifetime smoking (per pack-yr)^¶	−9.13	−7.82	0.00	−14.95	−8.72	−0.22
BMI (per unit)^\|\|	9.11	20.17	−0.15	−0.69	−0.12	−0.03
Height (per cm)^**	38.53	53.70	−0.12	33.62	42.58	−0.07
Square of height (per cm²)^††	−0.37	0.06	−0.01	0.004	0.16	−0.01
Study site
Chicago^‡‡	−91.64	−206.26	1.61	4.12	60.64	−1.67
Minnesota	56.15	−22.97	1.46	−56.82	−57.75	−0.18
Oakland^§§	−44.11	−193.85	2.29	−58.77	−91.08	0.57

The data are the milliliters (for forced expiratory volume in 1 second [FEV₁] and forced vital capacity [FVC]) or ratios (for FEV₁:FVC) associated with each listed covariate, after adjustment for all other covariates listed. The intercept value is added to the covariate value (after appropriate weighting) to obtain the lung-function estimate. Bold type indicates a significant association (P<0.05). CARDIA denotes the Coronary Artery Risk Development in Young Adults study.

^†

P<0.001 for all coefficients for intercept.

^‡

For coefficients for age, P = 0.03 and P = 0.007 for FVC and FEV₁:FVC among men, respectively, and P = 0.03 and P<0.001 for FEV₁ and FEV₁:FVC among women, respectively.

^§

For coefficients for African ancestry, P = 0.004 and P<0.001 for FEV₁ and FVC among men, respectively, and P = 0.001 and P = 0.007 for FEV₁ and FVC among women, respectively.

^¶

For coefficients for pack-years of smoking, P = 0.003 and P = 0.004 for FEV₁ and FEV₁:FVC among women, respectively.

^||

The body-mass index (BMI) is the weight in kilograms divided by the square of the height in meters. For the coefficient for BMI, P = 0.01 for FVC among men.

^**

For coefficients for height, P<0.001 for FEV₁ and FVC among men and women, and P = 0.03 and P = 0.04 for FEV₁:FVC among men and among women, respectively.

^††

For the coefficient for the square of height, P = 0.051 for FEV₁:FVC among women.

^‡‡

For the coefficients for Chicago, P = 0.03 for FVC among men and P = 0.02 for FEV₁:FVC among women.

^§§

For the coefficients for Oakland, P = 0.02 for FVC and for FEV₁:FVC among men.