Does Snoring Time Always Reflect the Severity of Obstructive Sleep Apnea?

OBJECTIVES: Although it is commonly believed that the degree of snoring reflects the severity of obstructive sleep apnea (OSA), there is often a mismatch between the improvement in OSA and the decrease of snoring time following OSA treatment. The aim of this study was to determine the relationship between OSA severity and snoring time.

METHODS: A total of 280 subjects who complained of snoring were divided by apnea-hypopnea index (AHI) into 5 groups. The snoring rate (the amount of sleep time spent snoring divided by the total sleep time) and the clinical data including polysomnographic findings were compared and analyzed.

RESULTS: There was no significant correlation between AHI and snoring rate (r = -0.038, P = .524). The snoring rate in the control group was significantly lower than that in the moderate ( P < .001) and severe ( P = .003) groups. The snoring rate in the very severe group was significantly lower than those in the mild ( P < .001), moderate ( P < .001), and severe ( P < .001) groups. However, there was no significant difference between snoring rates in the control group and the very severe group ( P = .832).

CONCLUSIONS: The change in snoring rate according to the severity of AHI showed an inverted U-shaped pattern, with a peak in the moderate OSA group.