Medical Costs per QALY of Statins Using the Swiss
Transcription
Medical Costs per QALY of Statins Using the Swiss
Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch Medical Costs per QALY of Statins Using the Swiss Medical Board (SMB) assumptions: Observed Effects in Two Large Primary Prevention Cohorts from Germany and Switzerland Michel Romanens1, Franz Ackermann1, Thomas Szucs2, Isabella Sudano3, Ansgar Adams4 1 2 3 4 Vascular Risk Foundation (Varifo), Olten European Centre of Pharmaceutical Medicine (ECPM), Basel University Heart Center Cardiology, University Hospital Zürich, Zürich, Switzerland, Gesundheitsvorsorge und Sicherheitstechnik GmbH, Bonn, Germany Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch Background - In June 2014 the SMB publishes a report showing costs per quality adjusted life years (Costs/QALY) to be extremely unfavorable (210’000 SFr) for statins in primary care in subjects having an ESC risk of 0.9% in 5 years. - As a consequence, in otherwise cardiovascular healthy subjects without diabetes mellitus or familial hypercholesterolemia, the SMB recommends statins in primary care only in subjects with a calculated ESC risk of ≥7.5% in 10 years. - The rationale for this apparent gap warrants further elucidation. - Further, costs/QALY at various cutoffs and it’s effect in cardiovascular disease prevention at the primary care level have not yet been reported. - The SMB Statin report is available at http://www.medicalboard.ch/fileadmin/docs/public/mb/Fachberichte/2014-0721_Bericht_Statine_Final_Anpassung.pdf Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch AIMS - We aim to determine Costs/QALY for various cutoffs of ESC risk using the SMB assumptions. - We aim to determine, whether Costs/QALY at different ESC risk levels correlate with the number needed to treat (NNT) in the SMB assumptions. - Based on various NNT, we aim to derive the ideal ESC risk cutoff for costs/QALY, allowing an NNT of 25 to be adequate. - We aim to test various ESC risk cutoffs in two large healthy populations from Switzerland (CH) and Germany (DE) to detect a coronary risk equivalents defined by the total carotid plaque burden, a highly sensitive and specific marker of future fatal and nonfatal myocardial infarction. Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch METHODS (1) - The EFFECT MODEL of the SMB to calculate costs/QALY is: - for 1 fatal AMI, 4.5 nonfatal AMI occur - relative risk reduction per 1 mmol/l LDL is 22% - cost per fatal AMI is CHF 8'500, per nonfatal AMI is CHF 25'000 in the first year and CHF 8'000 in subsequent years - loss of QALY is 1.0 for fatal and 0.2 for nonfatal AMI - annual preventive medical cost per individual including statin costs CHF 470 SFr - all AMI events occur uniformly after 50% of the total observation time. - The calculations are available at www.varifo.ch/QALYVarifo.xlsx Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch METHODS (2) - We defined the numbers of subjects exhibiting a coronary risk equivalent using carotid atherosclerotic plaque imaging and calculated the sensitivity (SENS) and the specificity (SPEC) of various ESC cutoffs to detect these subjects. - SENS: sensitivity deals with the diseased subjects - [true positives] / [true positives and false negatives] - SPEC: specificity deals with the healthy subjects - [true negatives] / [true negatives and false positives] - NNT: 1 / absolute risk reduction - Examples: - 10% absolute risk reduction = 100/10 = NNT 10 - 1% absolute risk reduction = 100/1 = NNT 100 Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch METHODS (3) - Carotid imaging were obtained by ultrasound (linear probe 7-14 MHz) - Imaging was performed with the identical imaging technique in CH and DE - Total Carotid Plaque Burden was determined from both carotid arteries - Each carotid plaque was traced longitudinally and added together, ending up with the total plaque area (TPA) in mm2. - we used TPA ≥80 mm2 (TPA80) to define high long-term (≥20% in ≥10 years) coronary risk (Arterioscler Thromb Vasc Biol. 2014;34:226-230) Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch RESULTS (1) - 1 Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch RESULTS (1) - 1 Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch Results (2) Sensitivity and specificity of ESC risk cutoffs the detect a coronary risk equivalent defined by carotid plaque imaging (TPA) Population (N) Female (%) Mean age (years±SD) TPA ≥80 mm2 SENS/SPEC ESC 1.8% 10 years SENS/SPEC ESC 3.3% 10 years SENS/SPEC ESC 5.0% 10 years SENS/SPEC ESC 7.5% 10 years CH 2203 1083 (49%) 57±7 22% 60/79 30/93 11/98 4/99 DE 2942 989 (34%) 46±10 15% 30/95 7/100 2/100 0.5/100 Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch Discussion (1) Costs/QALY - Using the Costs/QALY assumptions of the SMB we find that the effect of statins correlates with the NNT. - Using a model with an ESC risk of 0.9% in 5 years, costs/QALY are 210’000 SFr. (NNT 91) - Using a Model with an ESC risk of 7.5% in 10 years, costs/QALY are 2’089 SFr. (NNT 11) - The middle way cutoff may be more suitable: - Using a Model with an ESC risk of 3.3% in 10 years, costs/QALY are 40’261 SFr. (NNT 25) NNT Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch Discussion (2) - The conclusion of the SMB has to be questioned, since there is a gap between the presented costs/QALY of 210’000 SFr and the recommended cutoff of ESC 7.5% to treat with statins. - Using the SMB cutoff of ESC 7.5% would leave near 100% of healthy subjects with a coronary risk equivalent untreated with statins. - Using the SMB cutoff of ESC 7.5% creates an obsolescence for measuring Cholesterol in primary care. Medical Costs per QALY of Statins Using SMB assumptions SGIM Annual Meeting 2015 (FM277): M. Romanens et al / www.varifo.ch Conclusion - We find statins to have costs per 1 mmol/l of LDL reduction of CHF 40'000/QALY (NNT 25) for an ESC risk of 3.3%, when we use the SMB assumptions. - With ESC 7.5% (SMB guide), many subjects with confirmed high risk atherosclerosis would presumably not be treated (SENS 4% in CH, 0.5% in DE), creating a situation, where there is an obsolescence for Cholesterol measurements (because high LDL would not be treated anyway). - Further studies are needed to test the SMB statin effect assumptions, since the SMB assumptions have not been evidenced in reality. - In the future, costs per QALY should be calculated with inclusion of medical and social costs. - In the mean time, we strongly recommend to adhere to the international guidelines for initiation of statin treatments in healthy subjects.