Antipsychotic drug prescriptions triple in the US

by Setrok Layl on January 15th, 2011
New Scientist – Health

Doctors are prescribing too many expensive antipsychotic drugs, often for conditions where there is little evidence they work, say US researchers.

PRESCRIPTIONS for antipsychotic drugs have more than doubled in the US over the past 15 years, often given for conditions for which there is scant evidence they work.

Antipsychotic drugs are often given for conditions for which there is scant evidence they work.

Expensive antipsychotics were originally approved to treat schizophrenia. They are now also prescribed for conditions including anxiety disorders and dementia, even though the Food and Drug Administration has not approved these off-label uses. The side effects of such drugs can include diabetes, weight gain and an increased risk of heart disease.

Caleb Alexander at the University of Chicago and colleagues analysed the results of a survey of visits to doctors between 1995 and 2008. In the sample population, the prescriptions of antipsychotics went from 6.2 million in 1995 to 16.7 million in 2006 and fell to 14.3 million in 2008. Off-label prescriptions also doubled during this time (Pharmacoepidemiology and Drug Safety, DOI: 10.1002/pds.2082).

Alexander points to ways to combat the trend, such as reducing heavy drug marketing and raising awareness of off-label prescribing.

Design, setting, and measurements

We used nationally representative data from the IMS Health National Disease and Therapeutic Index to describe outpatient antipsychotic use. The primary outcome was the volume of visits where antipsychotics were used for specific indications (treatment visits). We also quantified use without U.S. Food and Drug Administration approval (off-label use) and off-label use with compendium data suggesting an uncertain evidence base.

Results

Antipsychotic use increased from 6.2 million (M) treatment visits (95% CI, 5.4–7.0) in 1995 to 16.7 M visits (15.5–18.2) in 2006, then declined to 14.3 M visits (13.0–15.6) by 2008. A shift occurred from typical agents in 1995 (84% of all antipsychotic visits) to atypical agents by 2008 (93%). As they declined, typical medications shifted toward use in schizophrenia (30% in 1995 to 48% 2008). In contrast, use of atypical agents expanded for bipolar affective disorder (10 to 34%), remained stable for depression (12 to 14%), and declined for schizophrenia (56 to 23%). Overall, antipsychotic use for indications without FDA approval increased from 4.4 M visits in 1995 to 9.0 M in 2008. The estimated cost associated with off-label use in 2008 was US$6.0 billion.

Conclusions

Atypical use has grown far beyond substitution for the now infrequently used typical agents. Antipsychotics are increasingly used for conditions where FDA approval and associated clinical evidence is less certain. Despite the value of innovation, the benefits of widening atypical antipsychotic use should be weighed against their cost, regulatory status, and incomplete nature of available evidence.