Drug-Related Morbidity and Mortality: A Cost-of-Illness Model

Background: Preventable drug-related morbidity and mortality represent a serious medical problem that urgently requires expert attention. The costs to society of the misuse of prescription medications, in terms of morbidity, mortality, and treatment, can be immense. To date, research has primarily documented increased rates of hospitalization secondary to medication noncompliance and/or adverse drug effects. Objectives: To develop a conceptual model of drug-related morbidity and mortality, and to estimate the associated costs in the ambulatory setting in the United States. Methods: A probability pathway model was developed to estimate the cost of drug-related morbidity and mortality in the United States. Pharmacist practitioners were surveyed to determine conditional probabilities of therapeutic outcomes owing to drug therapy. Health care utilization and associated costs owing to negative therapeutic outcomes were estimated. Results: Drug-related morbidity and mortality was estimated to cost $76.6 billion in the ambulatory setting in the United States. The largest component of this total cost was associated with drug-related hospitalizations. When assumptions of the model were varied, the estimated cost ranged from a conservative estimate of $30.1 to $136.8 billion in a worst-case scenario. Conclusions: The cost of drug-related morbidity and mortality in the ambulatory setting in the United States is considerable and should be considered in health policy decisions with regard to pharmaceutical benefits. Policies and services should be developed to reduce and prevent drug-related morbidity and mortality.