Association of thiazolidinediones with gastric cancer in type 2 diabetes mellitus: a population-based case–control study

BACKGROUND: It has been shown that peroxisome proliferator-activated receptors (PPAR) have physiological and pharmacological ligands. The objective is to assess the association between thiazolidinediones (TZDs) and the occurrence of gastric cancer. METHODS: We conducted a population-based nested case–control study. Data were retrospectively collected from the National Health Insurance Research Database (NHIRD). The cases consisted of all diabetes mellitus (DM) patients aged 30 to 99 years, and who had a first time diagnosis of gastric cancer in the study cohort. The controls were matched to cases by age, sex, and index date. The adjusted odds ratio (OR) and 95% confidence interval (CI) were estimated by using multiple logistic regression. RESULTS: Records from 357 gastric cancer and 1,428 selected matched controls were included in the analyses of gastric cancer risk. A total of 7% or 9.5% of the cases and 10.8% or 14.8% of the controls had used any quantity of at least 2 prescriptions for pioglitazone or rosiglitazone, respectively. After adjusting for possible confounders, pioglitazone (OR = 0.93, P > 0.05) and rosiglitazone (OR = 1.21, P > 0.05), had no significant association of decreasing gastric cancer. After adjusting for possible confounders, pioglitazone (OR = 0.70, P > 0.05) or rosiglitazone (OR = 0.79, P > 0.05), had no significant trend toward decreasing gastric cancer risk with increasing cumulative doses ≥ 260 defined daily doses (DDDs), respectively. Moreover, adjusting for possible confounders pioglitazone (OR = 0.68, P > 0.05) or rosiglitazone (OR = 0.74, P > 0.05) had no significant trend toward decreasing gastric cancer risk with increasing cumulative doses ≥ 1 year, respectively. CONCLUSIONS: Our results did not show evidence to support that TZD derivatives in DM patients reduces gastric cancer occurrence.