Table 1

Characteristics of patients with chronic obstructive pulmonary disease (COPD) and smoking-related phenotypes studied

Cohort
NETT n=362*Norway n=851*ECLIPSE n=1734*COPDGene n=494*
Characteristics
 Men*, n (%)234 (64.6)511 (60.0)1160 (66.9)242 (49.0)
 Age in years*, Mean (SD)67.4 (5.8)65.5 (10.1)63.7 (7.1)64.7 (8.1)
 Pack-years smoked*, Mean (SD)66.1 (30.9)32.1 (18.6)50.4 (27.4)54.8 (26.8)
 Post-bronchodilator FEV1 (% pred.)*, Mean (SD)29.1 (7.8)50.7 (17.5)44.8 (14.7)48.7 (18.4)
 Post-bronchodilator FEV1/FVC*, Mean (SD)0.32 (0.06)0.51 (0.13)0.45 (0.12)0.48 (0.13)
 Enrolment, Years1998–20022003–20052005–20072008–2009
 Genotyping technology, ChipIllumina Quad 610Illumina HumanHap 550 V1, V3, and DuoIllumina HumanHap 550 V3Illumina Human Omni1-Quad
Phenotype studied
 Age at smoking initiation
  Mean (SD)16.6 (3.6)18.7 (5.1)16.9 (4.4)16.8 (4.4)
  Number of patients with non-missing phenotype3628511690494
  Lambda inflation factor0.9860.9891.0190.997
 Lifetime average CPD
  Mean (SD)32.4 (13.5)15.7 (7.8)25.5 (12.4)27.6 (11.8)
  Number of patients with non-missing phenotype3618511734494
  Lambda inflation factor1.0020.9961.0180.996
 Smoking cessation
  Current smokers, n (%)0 (0)404 (47.5)610 (35.3)150 (30.6)
  Former smokers, n (%)362 (100)447 (52.5)1120 (64.7)340 (69.4)
  Lambda inflation factor1.0000.9980.995
 Current CPD
  Mean (SD)13.1 (6.9)15.6 (10.8)18.4 (12.4)
  Number of patients with non-missing phenotype398565150
  Lambda inflation factor0.9951.0050.997
  • * Calculated for patients with at least one non-missing phenotype.

  • For patients with reported current CPD >0.

  • CPD, number of cigarettes smoked per day; ECLIPSE, Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; NETT, National Emphysema Treatment Trial.