In this systematic review, the investigators sought to find the cost of treatment-resistant schizophrenia and schizoaffective disorder in the United States, which they estimate affects 500,000 people (1). They defined treatment resistance as failure to respond to one or more adequate antipsychotic trials, which is more inclusive than most clinical definitions. They examined studies published from 1996 through 2011 and included 65 that met their criteria. In addition to demographics and illness characteristics of the study populations, they looked at psychiatric and medical comorbidities, employment, and mortality including suicide. They also attempted to obtain data on treatment costs, productivity losses, and impacts on quality of life.
The rate of treatment response in clinical trials among TRS patients ranged from 14% to 25%. Compared with the general population, the TRS population had on average higher rates of substance use including tobacco addiction, of aggressive behavior, and a high burden of adverse medication effects. Suicidal ideation or behavior occurred in 54% of patients.
The standard metric for burden of disease in a population is quality-adjusted or disability-adjusted life-years (QALYs or DALYs), which include impacts on longevity and quality of life, but the investigators found no studies that calculated these for TRS or TRSA. One study provided health utility weights, which estimate the impact of a disease on a scale in which 0 is equal to death and 1 is equal to perfect health. Severe schizophrenia was given a weight of 0.56, similar to that of people on chronic renal dialysis; based on this, the investigators estimated a loss of 145,000 QALYs per year.
Estimates of total health-care costs of TRS were $66,360 to $163,795 per patient-year in 2012. This compares with an estimate of about $15,500 to $22,300 for non-treatment-resistant patients. In TRS and non-TRS, about half these costs were attributable to inpatient treatment. The authors estimated that the 20% of patients with TRS account for up to 80% of all schizophrenia health-care costs. No studies looked at lost productivity, but unemployment likely exceeds 70% in TRS patients, and costs related to crime, incarceration, and care-giver impacts were also lacking.
The limitations of the study are mostly related to deficiencies in the body of publications on the societal and personal impacts of this disorder. Given these gaps in data, the researchers believe that their findings represent an underestimate of the costs of TRS. This illness is costly on many levels, some of which have not been adequately studied and others of which may not be quantifiable.
1. Kennedy JL, Altar CA, Taylor DL, Degtiar I, Hornberger JC. The social and economic burden of treatment-resistant schizophrenia: a systematic literature review. Int Clin Psychopharmacol. Published online 29 Aug 2013. Abstract