Risk factors and correlates of snoring and observed apnea

Sleep Med. 2008 Mar;9(3):290-6. doi: 10.1016/j.sleep.2007.04.018. Epub 2007 Jul 19.


Background and purpose: Risk factors and correlates of snoring and observed apnea in the population are not well known. This study aimed to assess risk factors and correlates of snoring and observed apnea.

Methods: Parents and grandparents of students from 20 randomly selected primary schools in urban and rural areas of Kirikkale, Turkey were asked about respiratory diseases, psychological distress and sleep-related disorders, using the Respiratory Questionnaire, Hospital Anxiety and Depression (HAD) scale and Sleep Questionnaire, respectively, which were returned by their children.

Results: Out of 13,225 parents and grandparents of primary school students 12,270 returned the questionnaires, for an overall response rate of 92.7%. Snoring and the observed apnea were more prevalent among subjects from rural than those from urban areas (52.6% vs. 46.6%, odds ratio (OR): 1.2, p<0.001 and 16.2% vs. 10.1%, OR: 1.7, p<0.001, respectively). Exposure to biomass smoke and smoking were associated with an increased risk of snoring and observed apnea, after adjusting for gender, age, body mass index, income and education in the multivariate linear model. In all subjects, increases in performance ability, daytime sleepiness, psychological distress and dyspnea scores observed in categories indicating increases in snoring intensity and observed apnea frequency constituted a trend but did always not reach statistical significance. Lastly, prevalence of traffic accidents, falling asleep at the wheel and morning headaches increased with the increments of snoring intensity and apnea frequency.

Conclusions: Exposure to biomass smoke in rural areas may account for the higher prevalence of snoring and observed apnea. Snoring intensity and observed apnea frequency may increase prevalence of traffic accidents along with many unfavorable symptoms.

MeSH terms

  • Accidents, Traffic / statistics & numerical data
  • Adult
  • Aged
  • Cross-Sectional Studies
  • Disorders of Excessive Somnolence / diagnosis
  • Disorders of Excessive Somnolence / epidemiology
  • Environmental Pollutants / adverse effects
  • Female
  • Headache / epidemiology
  • Health Surveys
  • Humans
  • Male
  • Middle Aged
  • Risk Factors
  • Rural Population / statistics & numerical data
  • Sleep Apnea, Obstructive / diagnosis*
  • Sleep Apnea, Obstructive / epidemiology
  • Smoking / adverse effects
  • Smoking / epidemiology
  • Snoring / epidemiology
  • Snoring / etiology*
  • Statistics as Topic
  • Surveys and Questionnaires
  • Tobacco Smoke Pollution / adverse effects
  • Tobacco Smoke Pollution / statistics & numerical data
  • Turkey
  • Urban Population / statistics & numerical data


  • Environmental Pollutants
  • Tobacco Smoke Pollution