Increasing body mass index decreased the median duration of individual apneas, hypopneas, and desaturations in all OSA categories, while increasing desaturation depth in severe OSA (P<0.001).
Observational (n=723)
Does an increase in BMI affect the duration of individual obstruction events in patients with obstructive sleep apnea?
Higher BMI in OSA patients is associated with shorter duration of individual apneas and hypopneas but greater desaturation depth in severe OSA, suggesting AHI alone may not fully capture OSA severity across different body weights.
p-value: p=<.001
BACKGROUND: Obesity is one of the most prominent risk factors for obstructive sleep apnea (OSA). Weight loss decreases the number of shorter respiratory events (<40 s), whereas the number of longer events remains almost unchanged. However, it is unknown how body mass index (BMI) affects individual obstruction event severity within OSA severity categories when age, sex, smoking, daytime sleepiness, snoring, hypertension, heart failure, and sleeping posture are considered. Therefore, we investigated whether individual obstruction event severity varies with BMI within the OSA severity categories when considering the most important confounding factors. METHODS: Polygraphic recordings of 723 subjects without CPAP treatment and with an apnea-hypopnea index (AHI) of ≥5 events/hour were reanalyzed retrospectively. The effect of BMI on the severities of OSA and individual obstruction events was evaluated in general, within OSA severity categories, and between different BMI groups (ie, BMI < 25; 25 ≤ BMI < 30; 30 ≤ BMI < 35; 35 ≤ BMI < 40; and BMI ≥ 40 kg/m 2 ). RESULTS: AHI increased in mild and severe (β ≥ 0.10, P < .001) OSA categories, with increasing BMI. However, the proportion of apneas from all respiratory events decreased (β = −0.55, P = .068) with increasing BMI in all the OSA categories. An increase in BMI led to a decrease in the median duration of individual apneas, hypopneas, and desaturations in all OSA categories, whereas desaturation depth increased statistically significantly in the severe category (β = 0.20, P < .001). CONCLUSIONS: Because BMI is related to the duration of individual obstruction events, its effect on OSA severity is more complex than its effect on AHI would implicate. Therefore, overall severity of OSA may not be the same for non-obese patient and obese patient who have similar AHI. Thus, these patient-specific characteristics of individual breathing cessations should be considered when estimating the severity of disease and risk of related adverse health effects.
Leppänen et al. (Fri,) conducted a observational in Obstructive sleep apnea (n=723). Body mass index vs. Different BMI groups was evaluated on Severity of OSA and individual obstruction events (p=<.001). Increasing body mass index decreased the median duration of individual apneas, hypopneas, and desaturations in all OSA categories, while increasing desaturation depth in severe OSA (P<0.001).