In adults with type 2 diabetes, sleep quality scales can serve as useful tools for predicting obstructive sleep apnea, with similar predictive values observed across various questionnaires, according to findings published in the Journal of Diabetes.
“The risk of developing diabetes associated with sleep disturbances has been found to be comparable to that of other traditional risk factors as obesity, family history and physical inactivity. It has been suggested that sleep disturbances should be considered in the clinical guidelines for type 2 diabetes screening,” Athanasia Pataka, MD, of the respiratory failure unit at G Papanikolaou Hospital, Thessaloniki, Greece, and colleagues wrote in the study background. “Thus, a systematic screening for [obstructive sleep apnea] in patients with [type 2 diabetes] with easy-to-use and accurate screening tools is warranted.”
In a retrospective study, researchers analyzed data from 350 patients with type 2 diabetes and 350 controls without type 2 diabetes matched for age, sex, BMI and apnea-hypopnea index, all seen at the sleep clinic of the respiratory failure unit between 2009 and 2016.
Patients completed a questionnaire from the sleep laboratory assessing sleep habits, snoring, observed apneas, leg movements and nocturia. Patients also completed the Epworth Sleepiness Scale (ESS), a questionnaire designed to identify excessive daytime sleepiness; the Berlin Questionnaire (BQ), a questionnaire aimed at recognizing patients at high risk for obstructive sleep apnea in a primary care setting; the Athens Insomnia Scale (AIS), a questionnaire designed to identify and assess insomnia; and the Stop Bang (S-B), a questionnaire that assesses the risk for obstructive sleep apnea presence.
All patients underwent sleep studies scored via American Academy of Sleep Medicine guidelines. A reduction in airflow of at least 90% from baseline for a minimum of 10 seconds was defined as apnea; reduction in airflow of at least 30% for at least 10 seconds and oxygen desaturation of at least 4% from pre-event baseline was defined as hypopnea. The researchers compared the predictive values of the questionnaires, and receiver operating characteristic curves were employed to evaluate the discriminatory ability of each questionnaire in diagnosing obstructive sleep apnea.
In patients with and without type 2 diabetes, researchers found that the predictive values of the questionnaires improved with obstructive sleep apnea disease severity; however, statistically significant differences between the predictive values for those with and without type 2 diabetes were obvious only in mild obstructive sleep apnea.
The researchers found that in both groups, the highest sensitivities were provided by the BQ and S-B cut off 3. In patients with type 2 diabetes, the ESS demonstrated the highest specificity, positive predictive value, area under the curve and likelihood ratios, whereas STOP and S-B cut off 3 performed best in patients without type 2 diabetes. When S-B was assessed using a cutoff of 5, higher specificities and positive predictive values were observed. Conversely, sensitivities decreased in both groups with this cutoff, particularly the nondiabetic group, according to the researchers.
“In this study, sleep questionnaires were found to have almost similar predictive performance in patients with [obstructive sleep apnea] irrespective from the presence of type 2 diabetes,” the researchers wrote. “A highly sensitive screening tool, as BQ and S-B, may increase the accurate diagnosis of true positive cases and minimize the cost of the consequences of untreated disease. However, compared with sleep questionnaires, the out-of-the-center sleep monitoring devices have been proven more accurate for [obstructive sleep apnea] screening.” – by Jennifer Byrne
Disclosures: The authors report no relevant financial disclosures.