Success and failure of mirtazapine as alternative treatment in elderly stroke patients with sleep apnea—a preliminary open trial

More than two thirds of stroke patients suffer from sleep apnea. A recent study showed that mirtazapine reduced the respiratory disturbance index (RDI) of a stroke patient by 80%. These promising results prompted us to offer mirtazapine to non-depressed stroke patients who suffered from sleep apnea and refused treatment with a continuous positive airway pressure (CPAP) device. Polysomnography was performed between 2200 and 0600 hours. We examined ten inpatients [nine male, one female; mean age of 68.7 ± 1.5 years ± SE; body mass index of 26.1 ± 1.2 kg/m², basal ganglia bleeding (n = 3), middle cerebral artery ischemia (n = 4), basal ganglia ischemia (n = 1), cerebellar bleeding (n = 2)] in the Neurologic Clinic’s sleep laboratory. The mean duration of illness before the first polysomnography was 52.6 ± 11.4 days. Mirtazapine effectively consolidated sleep in all patients, i.e., sleep efficiency significantly increased from 63.1 ± 4.8% to 75.7 ± 5.0%. A moderate increase in RDI (137.4 ± 15.3% of baseline) occurred during initial mirtazapine administration (intake duration 15.8 ± 5.5 days). After 51.9 ± 8.4 days, the RDI was either reduced (51.9% in “responders” who were identified arbitrarily by a reduction in RDI ≥ 25% at any time point of the investigation) or increased (154.4% in “non-responders”). Mirtazapine administration was stopped in the four patients with increased RDI. Mirtazapine may be a probably effective treatment in stroke survivors with obstructive sleep apnea who refuse nasal CPAP treatment. As it may worsen central and mixed sleep apnea, patients who receive mirtazapine to alleviate sleep apnea or to control post-stroke depression with sleep disturbances should be monitored for changes in breathing parameters during sleep.