Cost-effectiveness Analysis Of Essential Hypertension Based On Gene Targeting Treatment By Metoprolol

Objective To evaluate the clinical effectiveness, safety, cost-effectiveness of prospectively individual treatment of Essential Hypertension based on gene targeting by metoprolol.Method 1. Polymorphism distribution of CYP2D6 andβ₁ adenoreceptor gene of 300 hypertensive patients from central region in Hunan province was investigated by PCR and PCR-RFLP method;2. 300 cases of patients with gene detection were included and divided into Group A and Group B randomly. Group A(165 cases) received conventional treatment (metoprolol, 100mg, Bid) for eight weeks. 133 cases with ofβ₁-AR gene Carrying Arg389 allele were employed in Group B(Targeting Gene Therapy Group). All subjects in Targeting Gene Therapy Groop were classified into three groups according to CYP2D6 genetyping: the poor metabolism group(PMB, 43 cases), intermediate metabolism group (IMB, 54 cases) and extensive metabolism group(EMB, 36 cases). PMB IMB and EMB were administrated with metoprolol for 25mg 100mg 200mg/day respectively, taking twice also. Blood pressures and side effects were observed during 8-week following-up.3. The health economic evaluation on Gene Targeting Therapy was determined by using the cost-effectiveness analysis and increment analysis after ending the treatment. Finally, sensitivity analysis was performed.Results 1. The observed frequencies of Arg389Arg, Gly389Arg and Gly389Gly genotypes ofβ₁-AR gene were 56% 42.67% and 1.33%, and the frequency of Arg and Gly allele was 77.33% and 22.67% respectively, the frequencies of CYP2D6 gene allele were ranked from high to low as *10(67.67 %),*l(20%), *2(7.17%) and *5(5.17%). Frequency of *10*10 genotype was the highest(39.33%). The proportion of PM, IM and EM populations was 47.67%, 25.33% and 27% respectively. All genotype and allele distribution followed Hardy-Weinberg equilibrium law, which was representative for group.2. The absolute reduction of DBP in Group B was more higher than that in Group A(11.0±9.2 mmHg vs 5.6±7.8 mmHg; P<0.05). And total effective rate in Group B was obviously higher than that in Group A (65.08% vs 47.4%; P<0.05). The comparison between Group A and subgroups B draw similar results. Degree and incidence of side effect were significantly lower in Group B than in Group A (P<0.01). The effective rate of the EMB was the highest in subgroups PMB, IMB and EMB, but the incidence rate of adverse reaction in EMB was the highest too(P<0.05).3. With cost- effectiveness analysis, to look upon blood pressure reduction as the effectiveness index, we found C/E of PMB on SBP and DBP reduction were lower than that of Group A (7.63 vs 16.14, 5.09 vs 20.82). To compared with Group A, C/E of IMB on SBP and DBP reduction were lower (10.77 vs 16.14, 11.85 vs 20.82), but C/E of EMB on SBP reduction was higher than that of Group A(16.69 vs 16.14), and the incremental cost-effectiveness ratio of EMB on SBP reduction was 17.35 as compared with Group A. To compared with Group A, C/E of EMB on DBP reduction was lower (17.39 vs 20.82), and the incremental cost-effectiveness ratio of EMB on DBP reduction was 14.04 as compared with Group A. So in terms of blood pressure reduction, Targeting Gene Therapy group was more cost effective, and the result was consistent with incremental cost- effectiveness analysis and Sensitivity analysis. When regard the total effective rate as the effectiveness index, we found C/E of PMB and IMB were lower than that of Group A (90.22 vs 249.96, 185.15 vs 249.96). To compared with Group A, C/E1 of EMB was higher (305.93 vs 249.96), and the incremental cost-effectiveness ratios of EMB were 436.94. The incremental cost-effectiveness analysis and Sensitivity analysis were similar with the cost-effectiveness.Conclusion 1. In our research, The proportion of PM and EM populations was 47.67% and 27%, which indicated 74.76% hypertensive population need individualized drug administration.2. Individual therapy based on gene targeting by metoprolol would be much safer and more effective than traditional administration.3. Targeting Gene Therapy by metoprolol would be more economic than traditional treatment.