Cardiovascular diseases (CVD) constitute one of the most significant causes of morbidity and are among the three most frequent causes of death in industrial countries. They comprise coronary heart disease (CHD), cerebrovascular disease and peripheral artery disease (PAD).
While death rates from CVD have been decreasing in many European countries including Austria, CVD still account for the largest proportions of hospital stays. The high burden of disease also has economic implications. Health care costs of 1.6 billion Euros, 6 % of the health care budget, were estimated for 2006 for Austria.
Several risk factors have been identified as causes of CVD, one of them being an elevated ‘Low Densitiy Lipoprotein-level’ (LDL-level). Among a number of measures to reduce serum cholesterol, pharmacological treatment with ‘HMG-CoA Reductase Inhibitors’ (statins) has become increasingly dominant since the beginning of the 1990s.
In clinical studies and meta-analyses, statins have shown significant risk reductions with respect to several clinical endpoints such as all-cause mortality, CHD mortality and CHD morbidity and exhibited a high level of safety.
Between 1996 and 2006 the number of prescriptions for statins rose from around half a million to 3.5 million in Austria, corresponding to 0.5 % and 3.1 % of all prescriptions respectively. While the costs per prescription decreased from around 40 Euros to 20 Euros due to the introduction of generics, overall expenditure rose sharply from 15 million Euros in 1996 to 94 million Euros in 2003 and then decreased to 76 million Euros in 2006.
b How many persons were taking statins between 1996 and 2006 in Austria and what are the expected population health gains from statin treatment in the secondary prevention of CVD for patients with CHD compared to standard advice without statins?
b What is the cost-utility of statin therapy compared to standard advice without statins in the secondary prevention of CVD for patients with CHD from a public payer perspective?
First, model outcomes from a validated and adapted Markov model from the UK that compared statin takers with non-statin takers (based on clinical trial evidence) were related to the actual number of Austrian statin patients from 1996 to 2006. Population effects with regard to non lethal and lethal types of CVD and revascularisation interventions were calculated. Second, model outcomes were used to analyse 10-year and life-time costutility ratios from a public payer perspective, discounted at 5 %. One-way sensitivity analyses were conducted to address uncertainty.
Population health gains: In the base case, it was demonstrated that roughly 36,200 patients started taking statins in 1996. The new cohorts per year were constantly rising and in 2006, about 108,000 new patients were estimated taking the medication. Overall, it was estimated that roughly 600,000 patients were taking statins in the 11-year observation period. Of these, around 856 fewer cases of unstable angina, 26,600 fewer MIs and 1,100 fewer strokes occurred, while roughly 6,100 more cases of stable angina were estimated when compared to not taking statins. In other words, 21 persons had to be treated with statins in order to avoid (or postpone) one patient going into a CVD health state. Furthermore, it was estimated that in the 600,000 statin takers, 10,300 fatal CVD events (10,200 CHD deaths and 100 cerebrovascular deaths) were avoided or postponed. Put differently, 59 persons had to take statins between 1996 and 2006 in order to avoid or delay one fatal CVD event.
Finally, the 600,000 statin patients can be weighed against around 7,000 revascularisation interventions avoided meaning 86 patients were treated to avoid one revascularisation intervention.
It was demonstrated in the model that in spite of statins about 42,000 cases of unstable angina, MI or stroke occurred and 25,400 fatal events (24,000 CHD deaths and 1,400 cerebrovascular deaths) happened. A total of 231,000 revascularisation interventions were carried out in spite of statin treatment.