Table 4.

Relationship between RBC arachidonic acid levels and SCC risk, stratified by current use of NSAIDs

Red blood cell arachidonic acid
P for trend
1st quartile2nd quartile3rd quartile4th quartile
All
n = 657OR11.001.20 (0.74-1.95)1.23 (0.76-2.00)1.86 (1.16-2.99)0.04
n = 563OR21.001.59 (0.93-2.72)1.45 (0.85-2.40)2.36 (1.38-4.02)0.001
NSAID nonuser
n = 589OR11.001.32 (0.79-2.19)1.43 (0.85-2.38)2.01 (1.21-3.34)0.03
n = 508OR21.001.82 (1.03-3.21)1.59 (0.99-2.78)2.59 (1.47-4.58)0.003
NSAID user
n = 66OR11.000.61 (0.11-3.32)0.15 (0.02-0.98)0.88 (0.18-4.30)0.77
n = 55OR21.000.43 (0.07-2.80)0.49 (0.06-4.29)1.14 (0.20-6.58)0.85
  • NOTE: Quartiles defined by control group (all controls for OR1 and controls without actinic keratosis for OR2); for 18:2n6t and 18:3n3 groups were categorized as detectable or not.

    OR1 is OR adjusted for age, sex, lab, tanning ability, freckles, history of actinic keratosis and includes all cases and controls. OR2 is OR adjusted for age, sex, lab, tanning ability, freckles and excludes controls with history of prior actinic keratosis. Model with all subjects also adjusts for NSAID use.