Obesity Linked to Higher OSA Odds, but Many with OSA Are Not Obese: Meta-analysis

The study, published in eClinicalMedicine, also found that obesity was more common in women and younger adults under 65. These findings highlight that OSA can occur in individuals beyond those who are obese, emphasizing the need for broader clinical awareness and vigilance.

Obesity is a well-established risk factor for obstructive sleep apnea, a condition marked by repetitive interruptions in breathing during sleep. Neda Esmaeili, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA, and colleagues examined the mutual prevalence of obesity and OSA, exploring how it varies across different age groups and sexes.

For this purpose, the researchers conducted a systematic review up to March 27, 2025, which included data from four community-based cohort studies in the US and Switzerland. The severity of OSA was measured using the apnea-hypopnea index (AHI), which calculates the total number of apneas and hypopneas with ≥4% oxygen desaturation per hour. Using random effects individual participant data (IPD) meta-analyses, the researchers estimated the prevalences, while logistic regression was employed to compare the odds of OSA across different weight groups.

The key findings were as follows:

• The study included 12,860 adults with a mean age of 66.6 years (± 7.3 years).
• Of the participants, 7,222 (56.2%) had obstructive sleep apnea (OSA) with an apnea-hypopnea index (AHI) of ≥5 events per hour.
• 3,309 (25.7%) participants were classified as obese, with a BMI of ≥30 kg/m².
• Among individuals with OSA, 31.5% had obesity, and 44.4% had an overweight status (BMI between 25 and 30).
• Among those with obesity, 74.3% had some form of OSA, while 59.8% of individuals with an overweight status had OSA.
• Obesity was more prevalent in females than males with OSA and in younger adults (<65 years) compared to older individuals.
• The odds of having OSA were 2.18 times higher in individuals with an overweight status and 4.84 times higher in those with obesity, compared to individuals with a BMI of less than 25 kg/m².

"Our analysis reveals that the majority of adults with OSA do not have obesity, with 44.4% being overweight and 23.5% having a normal weight or being underweight," the authors noted. They further emphasized, "Obesity was more prevalent in females and younger individuals (<65 years) with OSA. These findings highlight that OSA is not exclusive to obesity, reinforcing the need for personalized treatment plans."

Reference:

Esmaeili, N., Gell, L., Imler, T., Hajipour, M., Taranto-Montemurro, L., Messineo, L., Stone, K. L., Sands, S. A., Ayas, N., Yee, J., Cronin, J., Heinzer, R., Wellman, A., Redline, S., & Azarbarzin, A. (2025). The relationship between obesity and obstructive sleep apnea in four community-based cohorts: An individual participant data meta-analysis of 12,860 adults. EClinicalMedicine, 83, 103221. https://doi.org/10.1016/j.eclinm.2025.103221