Comparative analysis of cytochrome P450 isoform CYP2C9 in elderly and senile patients with that in healthy volunteers of the first period of middle age

Actuality. Cytochrome P450 enzymes activity tends to decrease with age, which is the reason why drugs’ metabolizing is slowed down. Such changes lead to a larger number of adverse side effects. This research is dedicated to evaluating activity changes of CYP2C9 isoform, which is involved in metabolism of a lot of significant drugs. Objective. The purpose of this research is to compare CYP2C9 isoform activity in elderly patients with that in people of the first period of middle age. Materials and methods. The work was carried out in 2 phases. The first phase evaluated the activity of cytochrome CYP2C9 in elderly and geriartric patients. The study included 18 elderly and senile patients, mean age 71,6 ± 9,6 years. In the second phase we evaluated the efficacy and safety of losartan trials in 18 healthy volunteers of the first period of mature age, mean age 26,3 ± 3,5 years. E-3174 (losartan’s metabolite) / losartan concentration in the urine ratio was used to evaluate CYP2C9 isoform activity. Results and discussion. According to the study the E-3174/losartan concentration ratio in elderly patients was 1,84 ± 0,15. In healthy young volunteers the E-3174/losartan ratio was 3,28 ± 0,77. In young patients the E-3174/ losartan ratio, the concentration of E-3174 and losartan concentration were higher than in elderly and senile patients, which indicates that the CYP2C9 activity in that group is lower than that in young volunteers of the first period of middle age. Conclusion. The activity of CYP2C9 in elderly people has a tendency to decrease.

drug therapy, CYP2C9 isoform, losartan, elderly people, senile people

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