Table 1.

Distributions of demographic and lifestyle factors, and urinary biomarkers at baseline by the treatment sequence assignment, The PEITC Intervention Study 2008–2013

Treatment sequence assignment
Characteristics or biomarkersPEITC-PlaceboPlacebo-PEITCP
Number of subjects4141
Age (years), mean (SD)40.9 (10.6)41.1 (9.6)0.939
Body mass index (kg/m2)a, mean (SD)28.0 (4.8)28.0 (6.3)0.957
Gender, n (%)0.376
 Male24 (59)20 (49)
 Female17 (41)21 (51)
Race, n (%)0.839
 African American8 (20)10 (24)
 Caucasian American28 (68)27 (66)
 Others5 (12)4 (10)
Level of education, n (%)0.179
 High school or lower14 (34)20 (49)
 College or higher27 (66)21 (51)
Cigarette smoking, mean (SD)
 Cigarettes/day19.3 (6.6)19.0 (6.7)0.843
 Years of smoking14.7 (10.3)17.9 (9.4)0.157
 Age at starting smoking (year)15.2 (4.9)15.1 (4.6)0.963
 Age when became regular smokers (year)18.6 (7.1)17.7 (5.2)0.514
Alcohol drinking, n (%)a0.784
 Never14 (35)17 (42)
 Monthly or less14 (35)12 (30)
 Weekly12 (30)11 (28)
GSTM1 and GSTT1 genotypes, n (%)0.585
 Present and present20 (49)18 (44)
 Present and null3 (7)4 (10)
 Null and Present14 (34)11 (27)
 Null and null4 (10)8 (19)
Urinary biomarkers, geometric mean (95% CI)b
 Total nicotine, ng/mg Cr2,114 (1,670–2,676)3,015 (2,389–3,806)0.039
 Total cotinine, ng/mg Cr2,839 (2,368–3,402)3,371 (2,819–4,031)0.190
 Total 3′-hydroxycotinine, ng/mg Cr6,638 (5,355–8227)6,993 (5,657–8,646)0.736
 Total nicotine equivalents, nmol/mg Cr45.1 (37.6–54.0)58.1 (48.6–69.5)0.054
 Benzene SPMA (pmol/mg creatinine)2.36 (1.68–3.28)2.38 (1.72–3.30)0.955
 Acrolein HPMA (nmol/mg creatinine)6.16 (5.14–7.38)7.04 (5.90–8.42)0.300
 Crotonaldehyde HMPMA (nmol/mg creatinine)4.22 (3.46–5.12)5.04 (4.14–6.12)0.207
 PGEM (pmol/mg creatinine)46.66 (38.68–56.26)42.68 (35.48–51.34)0.509
 8-iso-PGF (pmol/mg creatinine)0.90 (0.76–1.04)0.78 (0.68–0.90)0.233
  • aTwo subjects were excluded from this analysis due to missing data.

  • bOne subject who did not provide a urine sample at baseline was excluded from the analyses.