Pharmacotherapy in patients with comorbidity is a current issue for clinical practice. Combination of hypertension and musculoskeletal diseases can be found in 40% of outpatients, which requires simultaneous administration of different drugs. The main mechanisms of drug interactions are associated with pharmacokinetics or pharmacodynamics alterations. It has been proven that changes in drugs pharmacokinetics can be due to cytochromes P450 activity. The main symptom of musculoskeletal diseases is chronic pain, which requires long-term therapy with non-steroidal anti-inflammatory drugs (NSAIDs). The 2C19 isoenzyme takes part in metabolism of some NSAIDs. Losartan, the inhibitor of renin-angiotensinaldosterone system (RAAS), is also metabolized by the 2C9 isoenzyme and is quite often prescribed to outpatients to treat hypertension. Hence, an influence of genetic factors on efficacy and safety of antihypertensive drugs and NSAIDs combinations requires further studies.

Introduction. In recent years, data have been accumulated regarding possible associations between cognitive impairment and atrial fibrillation. The results of retrospective and prospective studies confirm that anticoagulant therapy in patients with AF can reduce the risk of cognitive impairment and dementia.Objective. To study the individual characteristics of elderly and senile patients with atrial fibrillation, influencing the choice of anticoagulant therapy, with a view to its subsequent optimization.Materials and methods. The study included 159 patients with atrial fibrillation of non-valvular genesis aged over 60 years. 4 groups of patients were formed. The largest number of patients received rivaroxaban and warfarin (36.4% and 34.6%, respectively). 26 (16.3%) patients were treated with dabigatran, 20 (12.6%) patients with apixaban. The risk of thromboembolic complications was assessed on the CHA2DS2-VASc scale. The HAS-BLED scale was used to assess the risk of bleeding. A pharmacogenetic study (carriage of polymorphic alleles of the CYP2C9 and VCORC1 genes) was conducted in 138 patients. Cognitive impairment was assessed by a Mini-Cog test and a battery of frontal tests.Results. Taking oral anticoagulants reduces the risk of stroke and dementia in patients; the presence of cognitive impairment, in  turn, significantly reduces the patient’s adherence to therapy and reduces the effectiveness of therapy. Patients’ adherence to therapy was significantly lower by 10–20% in patients with cognitive impairment according to the Mini-Cog test and a battery of frontal tests. In the absence of pronounced cognitive impairment (higher adherence to treatment) and availability and willingness to control INR, warfarin remains the drug of choice in patients with renal insufficiency.Conclusions. A number of problems with the use of oral anticoagulants in elderly patients with atrial fibrillation have been identified. The ease of use of new oral anticoagulants, the absence of the need to select doses and monitor therapy is an important factor when choosing a drug.