Association of oxidative metabolism phenotype and clinical efficacy of proton pump inhibitors in patients with gastroesophageal reflux disease
Aim. Research of the clinical efficacy of proton pump inhibitors in patients with gastroesophageal reflux disease (GERD) with various phenotypes of oxidative metabolism, detected using the marker drug aminophylline. Material and methods. 65 patients were included into the study. Oxidative metabolism phenotype was evaluated by the aminophylline half-elimination period (method of aminophylline salivary detection was used), and the phenotype groups were classified into «quick», «slow» and «very slow» metabolizers. Helicobacter pylori was diagnosed using the urease breath test. Clinical efficacy of the standard omeprazole dose (20 mg OD) was evaluated by relieving heartburn and pain syndrome. Results and discussion. The conducted research revealed that among 65 patients with GERD quick oxidation phenotype was detected in 32,3% of patients, and slow oxidation phenotype - in 49,2% of patients, while in 18,5% of patients very slow oxidation phenotype was detected. When evaluating the impact of treatment on GERD clinical signs, quicker relief of heartburn was noted in the subgroup of very slow metabolizers compared to quick metabolizers. When comparing quick and slow metabolizers, the frequency of Helicobacter pylori eradication was significantly lower in the subgroup of quick metabolizers as opposed to very slow ones. Conclusion. Assessment of the rate of drug oxidative metabolism in liver enables the individualization of omeprazole treatment in patients with GERD. Apparently, in quick oxidation phenotype it is necessary to increase the daily dose of omeprazole. Patients with GERD and slow oxidation phenotype should be expected to have significant short-term clinical effect of standard omeprazole doses. Eradication therapy with the standard doses of drugs was less effective both in clinical and economic terms in patients with GERD and quick oxidative metabolism phenotype, unlike slow and very slow metabolizers.