West J et al. (2004) Malignancy and mortality in people with coeliac disease: population based cohort study. BMJ 329: 716–719

Several studies have shown an increased risk of malignancy and mortality in patients with celiac disease, but robust data are lacking. Using the UK general practice database—the largest of its kind—West and colleagues have compared rates of malignancy and mortality in 4,732 people with celiac disease and 23,620 matched controls.

The study showed a modest increase in mortality in patients with celiac disease compared with the general population (hazard ratio [HR] 1.31, 95% CI 1.13 to 1.51) and the risk of any malignancy was similarly increased (HR 1.29, 95% CI 1.06 to 1.55). Since the excess risk of malignancy was greatest during the first year after diagnosis of celiac disease, the authors note that ascertainment bias may account for most of the increase. Analysis of subgroups showed that celiac disease patients were at increased risk of gastrointestinal cancer (HR 1.85, 95% CI 1.22 to 2.81) and lymphoproliferative disease (HR 4.80, 95% CI 2.71 to 8.50). Conversely, the risk of lung cancer was lower in people with celiac disease than in the control cohort (HR 0.34, 95% CI 0.13 to 0.95). It could not be ruled out, however, that this decreased risk was related to a lower proportion of smokers in the celiac disease group. The risk of breast cancer was also markedly reduced in the celiac disease group compared with controls (HR 0.35, 95% CI 0.17 to 0.72) and the authors suggest that this warrants further investigation.