Reassessment of the cost-effectiveness of hormone replacement therapy in Sweden: Results based on the Women's Health Initiative randomized controlled trial
Objectives: The purpose of the study is to reassess the cost-effectiveness of hormone replacement therapy (HRT) based on new medical evidence found in the Women's Health Initiative (WHI). Within a model framework using an individual state transition model, the cost-effectiveness of 50- to 60-year-old women with menopausal symptoms is assessed based on a societal perspective in Sweden.
Methods: The model has a 50-year time horizon divided into a cycle length of 1 year. The model consists of the following disease states: coronary heart disease, stroke, venous thromboembolic events, breast cancer, colorectal cancer, hip fracture, vertebral fracture, and wrist fracture. An intervention is modeled by its impact on the disease risks during and after the cessation of therapy. The model calculates costs and quality-adjusted life years (QALYs) with and without intervention. The resulting cost per QALY gained is compared with the value of a QALY gained, which is set to SEK 600,000. The model requires data on clinical effects, risks, mortality rates, quality of life weights, and costs valid for Sweden.
Results: The cost-effectiveness ratios are estimated at approximately SEK 10,000, which is below the threshold value of cost-effectiveness. On the condition that HRT increases the quality of life weight more than 0.013 units, the therapy is cost-effective.
Conclusions: In conclusion, given the new evidence in WHI, there is still a high probability that HRT is a cost-effective strategy for women with menopausal symptoms.
Key Words: Cost-effectiveness analysis; Hormone replacement therapy; Markov model.