Background: Frequent consumption of aspirin and nonsteroidal anti-inflammatory drugs (NSAID) has been associated with reduced occurrence of cancers of the esophagus, although potential modifying effects of other causal factors remain relatively unexplored.
Methods: We compared nationwide samples of Australian patients with adenocarcinomas of the esophagus (EAC; n = 367) or esophagogastric junction (EGJAC; n = 426) or esophageal squamous cell carcinoma (ESCC; n = 309) with control participants sampled from a population register (n = 1,580). Intakes of aspirin, other NSAIDs, and acetaminophen (paracetamol) were assessed from self-reports. We calculated odds ratios (OR) and 95% confidence intervals (95% CI) using multivariable logistic regression.
Results: Compared with never-users of aspirin, those who used aspirin at least weekly had significantly lower risks of EAC (OR, 0.48; 95% CI, 0.32-0.72), EGJAC (OR, 0.71; 95% CI, 0.49-1.01), and ESCC (OR, 0.63; 95% CI, 0.40-0.98). At least weekly use of other NSAIDs was also associated with reduced risks of EAC (OR, 0.74; 95% CI, 0.51-1.08), EGJAC (OR, 0.53; 95% CI, 0.37-0.77), and ESCC (OR, 0.46; 95% CI, 0.30-0.73). No association was observed between frequent use of acetaminophen and esophageal cancer. Risk reductions for EAC among users of aspirin and NSAIDs were greater among those who experienced at least weekly symptoms of reflux (OR, 0.26; 95% CI, 0.12-0.55 and OR, 0.41; 95% CI, 0.21-0.77, respectively) than those who did not experience reflux (OR, 0.96; 95% CI, 0.46-2.00 and OR, 0.78; 95% CI, 0.35-1.72, respectively). Recent use of NSAIDs in the past 5 years was associated with greater risk reductions.
Conclusions: Frequent use of aspirin and NSAIDs is associated with reduced occurrence of esophageal cancers, particularly among those with frequent symptoms of gastroesophageal reflux.