PARIS – Forty percent of patients with major depressive disorder who receive a selective serotonin reuptake inhibitor or serotonin norepinephrine reuptake inhibitor (SNRI) as their initial pharmacotherapy do not achieve the minimum therapeutic dose within 4 weeks of diagnosis, according to a real-world study of U.S. practice patterns.
This finding from a retrospective analysis of more than 60,000 adults diagnosed with major depressive disorder (MDD) during 2010-2015 and newly treated with an SSRI or SNRI as their first-line medication highlights an area where improved treatment delivery could lead to better outcomes, Rita Prieto, MD, PhD, said at the annual congress of the European College of Neuropsychopharmacology.
American Psychiatric Association guidelines emphasize the importance of early treatment and dose optimization as key to successful treatment of MDD. Failure within 4 weeks to reach even the minimum therapeutic dose – defined for purposes of this study as the starting dose as described in the APA guidelines – does not qualify as early dose optimization, according to Dr. Prieto of Pfizer in Madrid.It’s noteworthy that, in this study of 60,433 adult outpatients with MDD – 15% of whom also had a diagnosis of an anxiety disorder – those who reached the minimum therapeutic dose (MTD) of their SSRI or SNRI within 4 weeks of diagnosis had significantly better medication adherence than those who arrived at the MTD later. Eighty percent of the early achievers filled their prescriptions regularly enough that it could reasonably be inferred they were taking their medication more than 80% of the time, as was the case for only 71% of the late achievers, she continued.
The mean time to reach the MTD was 1.5 weeks in the early achievers and 23.1 weeks in the later achievers. More than 80% of the study group as a whole had achieved the MTD for their SSRI or SNRI by 3 months after diagnosis of MDD. However, by the end of 6 months, 12% of patients still were not there.
Time to initiation of first-line SSRI or SNRI therapy left something to be desired as well: 60% of patients were on medication within 2 weeks after diagnosis. An additional 22% initiated pharmacotherapy during weeks 3-12. After 6 months, however, 10% of the patients who eventually went on medication still had not started pharmacotherapy.
Early treatment initiators exhibited better treatment adherence: 80% of them took their daily medication more than 80% of the time, compared with 68% of the late initiators.
It’s possible that the early treatment initiators and MTD achievers were more severely ill. That’s suggested by the fact that 23% of the early MTD achievers received combination therapy with an additional antidepressant or antipsychotic agent for more than 30 days, compared with only 17% of the late achievers.
This study used claims data obtained from the Truven Health Analytics MarketScan Commercial and Medicare Supplement database. Dr. Prieto noted that an important study limitation was that the database did not yield information on remission rates and other clinical outcomes.
The study was funded by Pfizer.