Objectives/Introduction: Previous studies have shown that there are signs of both motor and sensory nervous lesions in the upper airway of patients with obstructive apnea (OSA) and, to a lesser extent, of habitual snorers.

Hypothesis: Snoring per se may damage upper airway neurons overtime, thereby causing the progression to manifest sleep apnea. To prove this, non‐snoring subjects, untreated snorers and CPAP‐treated OSA‐patients underwent repeated sensory testing in the upper airwayin a long‐time study.

Methods: Cold detection threshold (CDT) testing, a routine neurophysiological method to study sensory function, was performed at the soft palate and the lip. 64 subjects were initially tested in 2008 for their ability to perceive the sensation of cold and retested 6 ‐7 years later. 20 were non‐snoring controls, 24 untreated snorers and 20 had received CPAP. CDT‐testing was performed using the method of limits by a Medoc TSA 2001 equipment with an intra‐oral thermod.

Results: In untreated snorers AHI increased from average 9–12. Eight previously normal subjects had developed OSA (AHI/ODI >5). CDT:s worsened from 5.0°C to 14.5°C (p = 0.001). Three subjects had completely lost their cold sensitivity in the palate, whereas it was normal and unchanged on their lips. In non‐snorers there were no significant changes in AHI (mean values 2.0). Cold detection thresholds increased slightly from average 3.1°C to 6.0°C (p = 0.003). In the CPAP‐treated patients the CDT:s did not significantly change (from 5.1°C 2008 to 7.1°C in 2015).

Conclusions: CDT:s worsened much more in the untreated snorers than in the other two groups (p = 0.03). This group therefore risks developing poor sensitivity in the upper airway in a couple of years of habitual snoring. This could contribute to sleep apnea, since also the snorers′ respiratory disturbance had increased. In contrast, it seems that efficient treatment of OSA protects the sensory innervation, since the CPAP‐treated group maintained their sensitivity to cold.

Disclosure: Nothing to disclose.