Skip to main content

Advertisement

Table 1 Descriptive characteristics of the study population

From: DNA methylation and smoking in Korean adults: epigenome-wide association study

Characteristics (mean ± standard deviation or n (%)) Genome-wide methylation analysis in blood DNA (the Korean COPD cohort) Transcriptome analysis in lung tissue (Asan Biobank)
Never smoker (N = 39) Former smoker (N = 30) Current smoker (N = 31)
Male 6 (15.4) 30 (100) 30 (96.8) 188 (100)
Female 33 (84.6) 0 (0) 1 (3.2) 0 (0)
Age, years 72.9 ± 6.1 74.1 ± 7.4 71.5 ± 5.3 64.2 ± 8.7
Body mass index, kg/m2 23.2 ± 3.0 23.5 ± 2.7 22 ± 2.8 NA
Pack-year NAc 28.9 ± 19.6 35.7 ± 19.1 42.0 ± 20.6
Duration of smoking cessation, years NA 17.6 ± 7.5 NA NA
Urine cotinine, nmol/L 88.4 ± 3.2d 167.6e 29421 ± 21947 NA
Undetectablea 36 (92.3) 29 (96.7) 0 (0) NA
COPDb 19 (48.7) 20 (66.7) 21 (67.7) 98 (51.9)
  1. aUrine cotinine levels ≤56.8 nmol/L are marked as “undetectable” from the measurement using IMMULITE 2000 Immunoassay System (Siemens Healthcare Diagnostics Inc., Tarrytown, NY, USA)
  2. bChronic obstructive pulmonary disease
  3. cNot available
  4. dUrine cotinine levels in three never smokers were detectable
  5. eUrine cotinine level in only one former smoker was detectable and the level was 167.6 nmol/L