Effect of CPAP on Periodic Limb Movements of Sleep in OSA

sleep apnea mask
sleep apnea mask
Researchers assessed whether continuous positive airway pressure affected the frequency of periodic leg movements during sleep.

Incomplete resolution of breathing abnormalities did not contribute to periodic limb movements (PLM) of sleep in patients with obstructive sleep apnea (OSA), according to a study presented at the 2018 SLEEP meeting held June 2-6 in Baltimore, Maryland.

Researchers from Brigham and Women’s Hospital and Harvard Medical School, in Boston, Massachusetts, sought to determine whether resolution of breathing abnormalities in patients with OSA with continuous positive airway pressure (CPAP) therapy improved and/or contributed to symptoms of PLM of sleep, as measured by change in the PLM index. The researchers analyzed data from the Apnea Positive Pressure Long-term Efficacy Study (ClinicalTrials.gov Identifier: NCT00051363), which included 1105 participants with OSA whom were randomly assigned to treatment with active (n=588) or sham (n=547) CPAP therapy. Participants underwent polysomnography at baseline, during titration, and at follow-up visits at 2, 4, and 6 months. 

Of the total participants, 19.7% had PLM index of ≥10/h. There were no differences between treatment and sham groups in baseline PLM index or average change in PLM index from baseline to 6 months. A similar PLM index of ≥ 25/h was seen for both CPAP and sham groups at baseline (9.5% vs 9.1%, respectively) and at 6 months (14.7% vs 11.3%, respectively). At 6 months, 52.2% of participants receiving active CPAP had the same or higher PLM index compared with baseline vs 47.8% in the sham CPAP group. For those participants with a baseline PLM index ≥10/h, there was a decrease in PLM index in both active and sham CPAP groups (-4.2 ± 25.4 vs -4.8 ± 25.0, respectively), specifically in participants who reported >4 hours use per night (-4.3 ± 25.8 vs -8.3 ± 25.1, respectively).

The researchers concluded, “PLM occurrence was not suggestive of incomplete resolution of breathing abnormalities. We did not find any change in PLMS with CPAP therapy.”

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Budhiraja R, Epstein L, Pavlova M, et al. Impact of continuous positive airway pressure (CPAP) therapy of obstructive sleep apnea (OSA) on occurrence of periodic limb movements of sleep (PLMS). Presented at: SLEEP 2018; June 2-6; Baltimore, MD. Abstract 0663.