ESTIMATING SOCIETAL WILLINGNESS TO PAY BASED ON THE ATP III GUIDELINES FOR THE OPTIMAL START TIME FOR STATINS

Purpose: There is much debate about the dollar amount that should be used for one quality adjusted life year (QALY).  The most commonly used value of $50,000 per year dates back to the 1980s and has not been updated based on inflation or other factors.  We propose a method of estimating the implied monetary reward per QALY based on U.S. guidelines for initiating statin treatment.

Method: We solve an inverse optimization problem to compute the implied societal willingness to pay based on ATP III guidelines for statin initiation. We formulate our model as a linear program with constraints to represent a Markov decision process (MDP) for finding the optimal start time for statins.  Our model also includes constraints that define the current ATP III guidelines. The objective of our linear program is to minimize the difference in expected discounted future rewards between the optimal policy and the ATP III policy. We allow the monetary reward per QALY to be a decision variable for each of the decision epochs from age 40 to age 80.  With this inverse optimization method, we are able to estimate the implied monetary rewards for QALYs.

Result: Our analysis found the annual reward per QALY to vary between $117,438 and $152,870 for women and between $123,736 and $160,257 for men over a patient’s lifetime.  The mean annual reward is $135,327 for males and $132,603 for females. There is a pronounced upward trend in the reward value with respect to age with older patients having higher implied rewards per QALY.

Conclusion: The implied reward per QALY is higher than the commonly used value of $50,000. A value between $125,000 and $150,000 would be consistent with the ATP III guidelines.