Table 1.

Patient characteristics in the prospective cohort for all patients, nonprogressing patients, and progressing patients

CharacteristicAll N = 296Nonprogressing (n = 255)Progressing (n = 41)HR (95% CI)Pa
Ageb
 Young149129 (86.6)c20 (13.4)10.76
 Old147126 (85.7)21 (14.3)1.1 (0.59–2.0)
Sex, n (%)
 Female142121 (85.2)21 (14.8)10.95
 Male154134 (87.0)20 (13.0)1.0 (0.5–1.8)
Race, n (%)d
 White247216 (87.4)31 (12.6)10.10
 Non-white4939 (79.6)10 (20.4)1.8 (0.90–3.76)
Tobacco exposure, n (%)e
 Never smoked9171 (78.0)20 (22.0)1
 Former smoker125107 (85.6)18 (14.4)0.6 (0.33–1.18)0.15
 Current smoker8077 (96.3)3 (3.8)0.2 (0.06–0.67)0.009
Tobacco exposure, n (%)e
 Ever smoked205184 (89.8)21 (10.2)1
 Never smoked9171 (78.0)20 (22.0)2.1 (1.1–3.9)0.02
Tobacco-smoking history, n (%)f
 Light smoker11198 (88.3)13 (11.7)10.15
 Heavy smoker8881 (92.0)7 (8.0)0.5 (0.20–1.3)
Alcohol consumptiong
 Never or light drinker229199 (86.9)30 (13.1)10.58
 Heavy drinker5345 (84.9)8 (15.1)1.2 (0.57–2.7)
Site, n (%)
 Remaining sites130121 (93.1)9 (6.9)10.002
 Ventrolateral tongue/floor of mouth166134 (80.7)32 (19.3)3.2 (1.53–6.74)
Histology of index biopsy, n(%)
 Hyperplasiah3428 (82.4)6 (17.6)1
 Mild dysplasia127111 (87.4)16 (12.6)0.9 (0.33–2.22)0.76
 Moderate dysplasia135116 (85.9)19 (14.1)1.0 (0.39–2.46)0.96
Duration of follow-up, mo
 Median44.646.532.0
  • aP values were calculated with the use of the univariate Cox model.

  • bOld was defined as age above median (57.6 years).

  • cRow percentage is reported.

  • dRace was self-reported.

  • eSmoker was defined as consumption of more than 100 cigarettes in life time

  • fHeavy smoker was defined as a pack-year above the median (22.2). A pack-year is defined as the equivalent of smoking one pack of cigarettes per day for 1 year.

  • gAlcohol information is only available for 282 patients. Heavy drinker is defined as consumption of more than 14 drinks per week for women and 21 drinks per week for men. 1 drink = 8oz beer = 4oz wine = 1oz spirits.

  • hHyperplasia were from site of previous dysplasia.