Nerve Stimulation for Sleep Apnea Linked to Some Long-Term Heart Benefits

Hypoglossal nerve stimulation (HGNS) for obstructive sleep apnea (OSA) may have some longer-term cardiovascular benefits, but its effects in the short term painted a different picture, according to a retrospective cohort study.

For adults without pre-existing cardiovascular disease, HGNS was not associated with diabetes diagnosis within 2 years (HR 1.06, 95% CI 0.61-1.85), but was associated with a higher hazard of hypertension diagnosis during this period (HR 1.70, 95% CI 1.26-2.28), compared with matched controls who were candidates for the procedure but didn’t get it, reported Neil Kondamuri, MD, of the University of Chicago Medicine, and colleagues in JAMA Otolaryngology–Head & Neck Surgery.

Notably, these patients had lower hazards of diabetes diagnosis (HR 0.19, 95% CI 0.09-0.38) and hypertension diagnosis (HR 0.49, 95% CI 0.33-0.73) after 2 years.

Among patients who already had diabetes or hypertension, recipients of HGNS had a higher hazard of cardiovascular events both minor (HR 1.44, 95% CI 1.06-1.95) and major (HR 1.62, 95% CI 1.06-2.48) within the first 2 years compared with controls.

After 2 years, HGNS patients had no significant difference in risk of minor (HR 0.60, 95% CI 0.35-1.04) and major cardiovascular events (HR 0.65, 95% CI 0.31-1.36) compared with controls, although hazards began decreasing beyond that point (minor events: HR 0.42, 95% CI 0.22-0.79; major events: HR 0.40, 95% CI 0.17-0.93).

While prior studies have shown blood pressure benefits as soon as 1 month after surgery for OSA, “we did not expect HGNS to affect diagnosis of cardiovascular disease within 2 years because the risk of diagnosis, as measured by incident diagnosis codes in an insurance claim, is a long-term outcome,” Kondamuri and team noted, adding that the higher risk of hypertension and cardiovascular events within this time frame was unexpected.

Possible explanations include more opportunities for diagnosis with more healthcare visits for device checks and postoperative management, or it could be due to confounding by OSA severity, which wasn’t available in the database.

“Therefore, matched patients undergoing HGNS likely had greater baseline OSA severity and cardiovascular risk than controls, which could explain higher hazards of diagnosis,” Kondamuri and colleagues pointed out.

Other surgical treatments for OSA have been associated with cardiovascular benefits — including reductions in blood pressure, stroke, and mortality — so it’s possible HGNS is as well, the authors noted. Randomized trials of positive airway pressure therapy have not shown a significant difference in primary and secondary prevention of cardiovascular morbidity.

“As patients considering HGNS report reduction of cardiovascular risk as their primary treatment goal, our results may inform how primary care physicians, sleep specialists, and otolaryngologists counsel patients with OSA,” the authors wrote.

For this study, Kondamuri and team used data from the Merative MarketScan Commercial Database to compare 3,786 adults (median age 53, 67.7% male) who had an HGNS device implanted between 2015 and 2024 versus 3,395 matched controls who also had OSA, were nonadherent to positive airway pressure therapy, and otherwise met HGNS candidacy criteria but did not undergo implantation.

Limitations of the study included a lack of data on cardiovascular markers, race, ethnicity, and socioeconomic status, “which have been shown to affect cardiovascular outcomes and may be important confounders,” the authors noted.

“Further research is needed to clarify potential long-term associations with subsequent cardiovascular events,” they concluded.