The use of the CT90 value in predicting anxiety in OSA: could it be a useful parameter?

- OBJECTIVE: Obstructive sleep apnea (OSA) is characterized by recurrent epi-sodes of complete or partial obstruction of the upper airway leading to episodic desaturation. OSA patients often show symptoms of anxiety. Our study aimed to examine the presence and levels of anxiety in OSA and simple snoring rel-ative to control subjects and to investigate the correlation between anxiety scores and poly-somnographic, demographic, and sleepiness parameters. SUBJECTS AND METHODS: The study in-cluded 80 OSA, 30 simple snoring, and 98 con-trol cases. Demographic, anxiety, and sleep-iness data of all subjects were acquired. The Beck Anxiety Inventory (BAI) was used to deter-mine the level of anxiety. The Epworth Sleepi-ness Scale (ESS) was used to evaluate the sleep-iness level of participants. In addition, polysom-nography recordings of those in the OSA and the simple snoring group were acquired. RESULTS: Significantly higher anxiety scores were found in patients with obstructive sleep ap-nea and simple snoring compared to the control group (p<0.01, p<0.01, respectively). From the polysomnographic data obtained from OSA and simple snoring subjects, the CT90 values (cu-mulative percentage of the time spent at satu-rations below 90%) and the AHI showed a weak positive correlation between the level of anxi-ety (p=0.004, r=0.271; p=0.04, r=0.196, respec-tively). CONCLUSIONS: Our study concluded that polysomnographic data showing the depth and duration of hypoxia may be more reliable in showing neuropsychological disorder and hy-poxia-related comorbidities in OSA. The CT90 value can be used as a measure in the assess-ment of anxiety in OSA. Its advantage is that it can be measured with overnight pulse oximetry along with in-laboratory PSG and HSAT (home sleep apnea test).