Modified Sleep Apnea Severity Index and Cardiovascular Risk in CPAP-Intolerant OSA Patients

The modified sleep apnea severity index (mSASI) combines patient anatomy, weight, sleep study metrics, and symptoms into a composite OSA index ranging from 1 (least severe) to 3 (most severe). Our study aims to assess the association between the mSASI and cardiovascular (CV) risk factors in patients undergoing sleep surgery.

Retrospective cohort review.

Single-institution tertiary care center.

CPAP-intolerant OSA patients who underwent hypoglossal nerve stimulation, maxillomandibular advancement, or expansion sphincter pharyngoplasty at our institution from 2014 to 2021 were included. Cardiovascular comorbidities and 5-year Framingham Risk Score (FRS) were assessed at the preoperative visit. Chi-squared and Wilcoxon rank sum test analyses were performed using R Studio.

Of the 209 patients included, 118 had an mSASI = 1, 71 had an mSASI = 2, and 20 had an mSASI = 3. Patients with an mSASI of 2 or 3 were more likely to have HTN (33% vs 51%, p = 0.011). Baseline mSASI (β = 4.4, 95% CI 0.04-8.7) and age (β = 1.3, 95% CI 1.0-1.6) were independently associated with increased FRS on multivariable linear regression (p < 0.05). However, this association did not persist in secondary models excluding constituent components of mSASI and FRS.

The mSASI may offer additional benefits in assessing OSA risk severity based on CV risk factors compared to the AHI alone. However, given that this association was not replicated in the secondary analysis, further research is needed to evaluate the utility beyond its individual factors and traditional metrics alone.