TPNS Shows High Adherence Rates for Central Sleep Apnea Treatment | Healio

Automated Nerve Stimulation Shows High Adherence Rates in Central Sleep Apnea Treatment

Latest data suggest that an implanted device delivering transvenous phrenic nerve stimulation (TPNS) for central sleep apnea demonstrates remarkably high adherence rates, potentially exceeding those seen with traditional mask-based therapies. A retrospective analysis, published in the Journal of Clinical Sleep Medicine on March 17, 2026, indicates that over 80% of patients consistently used the device for at least four hours per night, meeting criteria for adequate therapy as defined by the Centers for Medicare & Medicaid Services (CMS) for continuous positive airway pressure (CPAP) adherence. Healio News reported on the findings.

How the Therapy Works

Central sleep apnea occurs when the brain fails to send proper signals to the muscles that control breathing during sleep. TPNS addresses this by directly stimulating the phrenic nerve, which controls the diaphragm, prompting it to contract and initiate breathing. The remedē system (ZOLL Respicardia) used in the study features automated activation. The device delivers therapy only when three conditions are met: the patient is within pre-programmed sleeping hours, their body is reclined past a programmed angle and they are not moving. This automated approach is believed to be a key factor in the observed high adherence rates.

Study Details and Findings

Researchers, led by Rami Khayat, MD, of Penn State Health sleep services, analyzed data from 131 adults who received the TPNS device. They assessed nightly therapy duration using device data collected over 18 months, with follow-up visits at 6, 12, 18, and 24 months. The median nightly therapy duration remained consistent across these time points, ranging from 5.7 to 6 hours. Notably, only 42 patients had data available at the 24-month mark due to the trial’s conclusion following FDA approval of the device in the United States.

The study highlighted a low rate of treatment discontinuation before the 6-month mark, with only two patients stopping therapy due to stimulation intolerance. At 6 months, 86% of patients met the CMS adherence threshold of at least 4 hours of use per night for 70% of nights. This proportion remained above 80% at all subsequent follow-up visits, reaching 90% at 24 months.

Why Adherence Matters

Adherence to sleep apnea therapy is a significant challenge. Mask-based therapies, such as CPAP, often suffer from lower adherence rates due to discomfort, inconvenience, and claustrophobia. The automated nature of TPNS may overcome some of these barriers, leading to more consistent treatment and potentially better outcomes. Researchers suggest that higher usage may translate to a greater reduction in the overall burden of central sleep apnea throughout the night.

Patient Reported Outcomes

Beyond device usage data, the study similarly examined patient-reported outcomes. After six months of active therapy, 95% of patients indicated they would choose to have the device implanted again. Patients with at least 4 hours of therapy per night reported greater improvements in quality of life and daytime sleepiness compared to those with less than 4 hours of use. Specifically, those with higher usage reported a larger decrease in their Epworth Sleepiness Scale scores (–2.5 vs. –2) at 6 months and (–3 vs. –1.5) at 12 months.

Expert Perspective: Automated Activation as a Key Advantage

Ashtaad Dalal, MD, FAASM, spokesperson for the American Academy of Sleep Medicine, offered a perspective on the study’s findings. Healio quoted Dr. Dalal stating that the results reinforce the intuitive advantage of an implanted therapy that activates automatically, removing the behavioral burden associated with mask-based therapies. He also noted that the study was limited by its retrospective design and the relatively homogeneous patient population, and that further research is needed to confirm these findings in broader clinical practice.

Limitations and Future Research

The researchers acknowledged several limitations of their study. The retrospective design, based on data from a clinical trial, may not fully reflect real-world adherence patterns. The patient population was carefully selected and monitored within a structured trial environment, which could have artificially inflated adherence rates. The relationship between longer therapy use and improvements in quality of life was observational and does not establish a causal link.

Future research should focus on larger, prospective studies to evaluate the effectiveness of TPNS in more diverse patient populations. These studies should also investigate the long-term impact of automated activation on physiological outcomes, cardiovascular risk markers, and overall symptom improvement. Long-term safety and efficacy data will also be crucial for establishing the role of TPNS in the management of central sleep apnea.

The process of evaluating new therapies for central sleep apnea involves ongoing data collection and analysis, as well as regular reviews by regulatory bodies like the FDA. Guidance from professional societies, such as the American Academy of Sleep Medicine, will also be updated as new evidence emerges. Patients with central sleep apnea should discuss the potential benefits and risks of TPNS with a qualified sleep specialist to determine if it is an appropriate treatment option.