Table 1.

Demographic, smoking behavior, and urine biomarker comparisons by cigarette type, mean (interquartile intervals)

CharacteristicMenthol smokers (n = 60)Regular smokers (n = 67)P
Race, % AA70.529.5<0.0001a
Age, y40.8 (35–47)35.7 (25–36)0.007a
BMI28.8 (24–32)25.4 (22–27)0.0007a
CPD (mean over 3 d)18.8 (11–22)17.0 (12–20)0.28
FTC nicotine, mg1.2 (1.1–1.3)1.0 (0.8–1.2)0.004a
FTC tar, mg16.1 (15–18)13.5 (11–16)<0.0001a
Number of years smoked23.7 (15–31)18.3 (9–25)0.006a
Age of smoking start, y15.9 (13–18)16.8 (14–18)0.25
Time after awakening to first cigarette, min24.8 (5–30)27.8 (5–45)0.30
Time from last cigarette to urine collection, min112 (60–148)86 (50–108)0.02a
FTND score5.6 (3–5)3.6 (2–5)0.22
Plasma cotinine, ng/mL202 (125–280)217 (124–266)0.48
Urine nicotine equivalents,b pmol/mg creat47.2 (32–79)59.8 (42–106)0.04a
Urine NNAL,b pmol/mg creat0.9 (0.6–1.7)1.2 (0.7–2.3)0.08
Urine total PAHs,b pmol/mg creat81.6 (54–117)115.2 (79–185)0.001a
Urine menthol,b μ/mg creat4.8 (2.3–12.9)2.1 (0.5–7)0.0009a
Menthol exposure score1.6 (0–2)1.4 (0–2)0.53

Abbreviation: AA, African Americans.

  • aSignificant difference between groups by chi-square (for race), t test (for arithmetic mean parameters), and Wilcoxon test (for geometric mean parameters).

  • bGeometric means.