Obstructive Sleep Apnea: Gender-Specific Adiposity and Metabolic Syndrome

MedicalResearch.com Interview with:

MedicalResearch.com Interview with:
Dr. Emilia Mazzuca
Biomedical Department of Internal and Specialistic Medicine (DIBIMIS)
Section of Pneumology and

Dr. Maria R Bonsignore, MD
Associate Professor in Respiratory Medicine
University of Palermo, Palermo, Italy

MedicalResearch.com: What are the main findings of the study?

Answer: Our main goal was to investigate gender-related interactions between obstructive sleep apnea (OSA) and obesity while taking associated metabolic abnormalities into account. We analyzed 423 men and 105 women previously studied for the association of OSA and the Metabolic Syndrome (MetS) (Bonsignore et al, Eur Respir J, 2012), to assess whether markers of general and visceral obesity were differently associated with OSA in men and women. Multivariate analysis showed that in men the apnea-hypopnea index (AHI), an indicator of OSA severity, was associated with waist circumference, a marker of visceral obesity, and body mass index (BMI); conversely, in women AHI was associated with hip circumference, a marker of subcutaneous fat deposition, and neck size.  The results were similar when patients without a diagnosis of MetS were analyzed; conversely, in patients with MetS, waist circumference was the only significant marker of OSA in both genders.

MedicalResearch.com: Were any of the findings unexpected?

Answer: Since many studies examined the relationship between markers of visceral obesity and OSA severity, the finding that hip circumference was the single best factor associated with severe OSA in women was unexpected. It is known that women with OSA are more obese than men, but data on adipose tissue distribution in female OSA patients are still scarce.

Another unexpected finding was that MetS correlated with OSA severity while the Visceral Adiposity Index (VAI), a new marker of cardiometabolic risk, did not. This result may in part be secondary to the fact that, differently from MetS, calculation of VAI does not include any blood pressure evaluation.

MedicalResearch.com: What should clinicians and patients take away from your report?

Answer: Assessment of obesity in men and women with OSA should take into account the different pattern of adipose tissue distribution. For example, a significant relationship between OSA severity and waist-to-hip ratio, a widely used marker of visceral obesity in clinical practice, was found only in men. Hip circumference values >107.5 cm in women, and waist circumference >104.5 cm in men were associated with severe OSA in our sample.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Answer: It is still unclear whether the metabolic profile of OSA is differently modulated in visceral versus peripheral obesity. This in an interesting area, with major impact on cardiovascular risk, which deserves further studies in women.


Mazzuca, E., Battaglia, S., Marrone, O., Marotta, A. M., Castrogiovanni, A., Esquinas, C., Barcelò, A., Barbé, F. and Bonsignore, M. R. (2013), Gender-specific anthropometric markers of adiposity, metabolic syndrome and visceral adiposity index (VAI) in patients with obstructive sleep apnea. Journal of Sleep Research. doi: 10.1111/jsr.12088

Last Updated on November 26, 2014 by Marie Benz MD FAAD