Efficacy of the device was assessed using objective measures based on the apnea-hypopnea index (AHI) and oxygen desaturation index (ODI) (primary outcomes), as well as on subjective measures using the Epworth Sleepiness Scale (ESS) and the Functional Outcomes of Sleep Questionnaire (FOSQ).
Explore This IssueAugust 2014
At 12 months, the study showed significant reductions in AHI and ODI. The AHI score decreased by 68%, from 29.3 events per hour at baseline to 9.0 events per hour at 12 months (P<0.001), and the ODI decreased by 70% from 25.4 events per hour at baseline to 7.4 events at 12 months (P<0.001). Significant changes were also seen from baseline to 12 months in ESS (decrease from 11.0 to 6.0, P<0.0001) and FOSQ (increase from 14.6 to 18.2, P<0.0001).
“Across the entire group, sleep apnea severity was reduced from the moderate-severe range to the mild range, which suggests good reduction in cardiovascular and health risks,” said Dr. Soose, who is a STAR trial investigator. Additional benefits seen in many patients, he said, included improvements in snoring, daytime sleepiness, and quality of life measures.
The study also showed a very good safety profile for the device, he said, with a less than 1% serious adverse event rate, very little post-operative discomfort, and minimal downtime.
New data: 18-month follow-up of STAR trial. After the 12-month follow-up period, the trial included a second phase, in which the first 26 consecutive responders were randomized 1:1 to either continuation on the device (therapy maintenance) or discontinuation of the device (therapy withdrawal).
Kingman Strohl, MD, director of the Sleep Medicine Fellowship Program at University Hospitals Case Medical Center and professor of medicine at Case Western Reserve University School of Medicine and University Hospitals Case Medical Center in Cleveland, Ohio, the senior author of the STAR study, presented updated results at 18 months follow-up on this group of patients. He said the results show a sustained benefit, reducing OSA severity and improving quality of life through 18 months, with a surgical response rate of about 70%. Overall, 123 patients remain active users of the device.
Results also showed that a one-week withdrawal from the therapy resulted in worsening of OSA and symptoms.
Similar to the 12-month data, the device was found to be safe over the longer duration of use, with few to no new adverse events seen between 12 and 18 months. Overall, over the entire 18 months, about 1.6% device-related adverse events were reported, but these were minor and did not stop patient use, said Dr. Strohl.