Reduction of prescribed citalopram dosages to a new safety limit was associated with significantly higher rates of hospitalization and mortality in a large veteran patient population previously treated with higher dosages.
“On Aug. 24, 2011, the FDA issued a safety communication that stipulated prescribed daily dosages of the antidepressant citalopram should no longer exceed 40 mg because of the risk of dosage-dependent QT interval prolongation,” Thomas S. Rector, PhD, of the Center for Chronic Disease Outcomes Research and Minneapolis VA Health Care System, and colleagues wrote. “The intended outcome of limiting dosages of citalopram to 40 mg/day was to reduce the incidence of fatalities and serious health problems due to QT interval prolongation. However, we observed several cases of suicidal ideation and hospitalization for worsening depression after citalopram dosages were reduced.”
To compare hospitalization and mortality incidence when higher doses of citalopram were or were not reduced to 40 mg per day or less, researchers analyzed national electronic medical records from the Veterans Health Administration. The study cohort included 35,848 veterans filling citalopram prescriptions for more than 40 mg per day when the safety communication was issued in August 2011. Study participants had a mean age of 58 years and mean prescription dosage of 64 mg per day.
Within 180 days following the initial safety communication, 60% of the cohort filled prescriptions for 40 mg per day or less.
After dosage reductions, all-cause hospitalizations or deaths (adjusted HR = 4.5; 95% CI, 4.1-5) and hospitalizations for depression or all-cause deaths (aHR = 2.2; 95% CI, 1.8-2.6) significantly increased.
Mortality (aHR = 1; 95% CI, 0.8-1.3) and hospitalizations for arrhythmias or all-cause deaths (aHR = 1.3; 95% CI, 1-1.7) did not decline.
“Reduction of prescribed citalopram dosages to a new safety limit was associated with a higher rate of hospitalization in a large patient population who had been treated with substantially higher dosages. We hope this research will encourage more empirical studies of patient outcomes after risk mitigation initiatives and thereby help to improve medication safety warnings and clinical risk management,” the researchers concluded. – by Amanda Oldt
The researchers report no relevant financial disclosures.