Obstructive Sleep Apnea Severity May Be Linked to Poststroke Depression

In patients who have experienced an ischemic stroke, the severity of obstructive sleep apnea (OSA) has been positively associated with 3-month poststroke depression (PSD). A hospital-based study was conducted at Jiangsu Provincial Second Chinese Medicine Hospital in Nanjing, Jiangsu, China, from March 2017 through December 2018, and results were published in the Journal of Stroke and Cerebrovascular Diseases.

Investigators sought to detect the correlation between OSA severity and PSD in patients with ischemic stroke. Study eligibility criteria included the following: age ≥18 years of age, symptom onset of <14 days, and willingness to participate in a polysomnography (PSG) examination and neuropsychological assessment. All of the study enrollees underwent an overnight PSG examination during their hospitalization. The median time from onset of symptoms to the performance of PSG was 11.0 days.

In the participants, the apnea-hypopnea index (AHI) was computed by averaging the total number of obstructive apneas and hypopneas per hour of sleep. Apnea was further classified as obstructive if respiratory efforts were observed either on the chest or abdominal inductance channel, or as central if no respiratory effort was seen. Additionally, OSA was diagnosed when ≥50% of respiratory events were of the obstructive type and central sleep apnea was diagnosed when >50% of respiratory events were of the central type. All participants were categorized into 4 groups, based on their AHI: no OSA: AHI <5/h, mild OHA: AHI ≤5/h to <15/h, moderate OSA: AHI <15/h to <30/h, and severe OSA: AHI ≥30/h.

A total of 265 patients were enrolled in the study and the median AHI was 14.0. The distribution of patients relative to OSA severity was as follows: no OSA: 18.1% (n=48), mild OSA: 32.1% (n=85), moderate OSA: 20.4% (n=54), and severe OSA: 29.4% (n=78).

Overall, 23.8% (n=63) of patients were diagnosed with PSD at admission and 32.5% (n=86) of patients were diagnosed with PSD at 3 months. Univariate analysis demonstrated that reduced OSA severity was significantly associated with PSD at 3 months (P =.003) but not at admission (P =.373). Results showed that participants with 3-month PSD were older (P =.002), mainly women (P =.006), more likely to have greater OSA severity (P =.004), more likely to develop white matter lesions (P =.003), more likely to have higher levels of AHI (P =.001), and more likely to have higher hypersensitive C-reactive protein levels (P =.006), compared with those without PSD. 

Per univariate logistic regression analysis, severe OSA was identified as a risk factor for PSD (odds ratio [OR], 3.86; 95% CI, 1.60-9.33; P =.003). In multivariable analysis, following adjustment for covariates, severe OSA was significantly associated with an increased risk for 3-month PSD (OR, 4.04; 95% CI, 1.38-9.62; P =.036), compared with patients without OSA.

The investigators noted that additional multicenter, longitudinal studies are warranted to more comprehensively evaluate these associations. In addition, pathophysiological mechanisms and therapeutic considerations remain to be established.

Reference

Li C, Liu Y, Xu P, et al. Association between obstructive sleep apnea and risk of post-stroke depression: a hospital-based study in ischemic stroke patients [published online May 13, 2020]. J Stroke Cerebrovasc Dis. doi:10.1016/j.jstrokecerebrovasdis.2020.104876