Abstract P544: Sleep Apnea Severity is More Strongly Associated With Cardiovascular Health Than a Composite Measure of Sleep Health in Adults With Sleep Apnea and Diabetes
Authors: Imes Christopher C , Bizhanova Zhadyra , Kline Christopher E , Sereika Susan M , Chasens Eileen 
Published: March 2020

Introduction:
Sleep health is multi-dimensional. The RSATED Sleep Health composite score, hereafter referred to as RSATED, includes regularity, satisfaction, alertness, timing, efficiency, and duration. RSATED has been associated with cardiovascular (CV) health in a nationally representative sample. However, the association between RSATED and CV health in adults with obstructive sleep apnea (OSA) and type 2 diabetes mellitus (T2DM) have not been examined.

Purpose:
This secondary analysis examined the associations between RSATED and CV health measures including body mass index (BMI), lipid levels, and physical activity.

Methods:
We used baseline data from the Diabetes Sleep Treatment Trial, a randomized controlled trial that examined if adults with co-existing OSA and T2DM treated with continuous positive airway pressure had better glycemic control compared to participants that received a non-therapeutic treatment. Data collected included questionnaires, anthropometric measurements, a lipid panel, objective physical activity (PA) data (BodyMedia), apnea-hypopnea index (AHI; ApneaLink Pro), and a modified Consensus Sleep Diary. RSATED was calculated using up to 7 days of sleep data and Epworth Sleepiness Scale (ESS). Individual components were given a score of 0 or 1 with 1 representing “good” sleep. “Good” sleep was defined as: >80% of awakenings occurring during the same time range (regularity); mean sleep quality of “good” or “very good” (satisfaction); ESS total score ≤10 (alertness); >80% of sleep midpoint occurring between 2-4 am (timing); sleep efficiency ≥85% (efficiency); and mean sleep duration of 7-9 hrs/night (duration). The total score could range from 0-6; higher scores represented better sleep. The associations between RSATED and CV health measures were examined using linear regression models. All models were adjusted for AHI, marital status, race, age, and education.

Results:
A total of 350 individuals underwent screening. Of the 253 participants with complete data, the majority were female (52.2%) and white (54.2%) with a mean (± SD) age of 56.6 ± 10.5 yrs, BMI of 34.2 ± 7.1, and AHI of 14.1 ± 15.1. Mean RSATED was 2.8 ± 1.2 (range 0-5). The RSATED score was not associated with any of the CV health measures. However, there was a trend for significance for better sleep health to be associated with greater vigorous PA (b = 0.46, p = .08). Whereas, greater AHI was associated with higher BMI, higher total cholesterol, greater sedentary time, and less moderate- and vigorous-intensity PA (p-values from .05 to <.0001).

Conclusions:
Among adults with co-existing OSA and T2DM, AHI was more strongly associated with measures of CV health than RSATED. While sleep health is essential, the underlying impact of OSA on CV health and its treatment should remain a priority. Future studies should continue to examine the associations between sleep health and other measures of health and wellness.