Association between skin temperature variability and sleep apnea severity: findings from a pilot study

Area of Science:

• Physiology
• Sleep Medicine
• Biomarkers

Background:

• Obstructive sleep apnea (OSA) can impair autonomic and vascular regulation, potentially affecting skin temperature variability (STV).
• Assessing STV may offer insights into OSA's physiological impact.

Purpose of the Study:

• To determine if STV, measured at distal and proximal sites, correlates with OSA severity (apnea-hypopnea index [AHI] and oxygen desaturation [T90]).
• To evaluate STV's potential as a non-invasive screening tool for OSA risk.

Main Methods:

• Polysomnography with simultaneous distal and proximal skin temperature recording in 18 participants.
• STV calculation using standard deviation, median absolute deviation, and Poincaré plots across different sleep stages (NREM, REM, wake).
• Statistical analysis included linear mixed-effect models, mediation analysis for BMI, and ROC analysis for screening potential, with FDR adjustment for p-values.

Main Results:

• A significant negative association was found between AHI and distal STV during NREM sleep (FDR-adjusted p < 0.001).
• T90 also showed a significant negative association with distal STV during NREM sleep (FDR-adjusted p < 0.01).
• Receiver-operating-characteristic (ROC) analysis demonstrated high discriminative ability for moderate-to-severe OSA (AUC: 0.93-0.97).

Conclusions:

• Diminished distal STV during NREM sleep is an independent indicator of OSA severity.
• STV shows promise as a non-invasive biomarker for effectively screening obstructive sleep apnea risk.