Sleeping over a sleep disorder - Awareness of obstructive sleep apnoea as a modifiable risk factor for hypertension and stroke: A survey among health care professionals and medical students

Systematic review and meta-analysis of the prevalence of obstructive sleep apnea in Indian adults

Obstructive sleep apnea (OSA) is a common sleep disorder associated with considerable morbidity. However, there is an underrepresentation of data from India and other developing countries in global reviews of OSA prevalence. This systematic review and meta-analysis examined the prevalence of OSA in India. The MEDLINE, Embase, and Scopus databases were searched for articles that reported the prevalence of OSA in the general Indian adult population using sleep studies. Eight studies were included comprising 11,009 subjects with mean age ranging from 35.5 to 47.8 years. On the Joanna Briggs Institute (JBI) checklist for prevalence studies, the study quality ranged from 3/9 to 9/9. Meta-analysis was performed using the random-effects model. The pooled prevalence of OSA (AHI ≥5 events/hour) was 11% overall (95% CI: 7%-15%; I2 = 98.0%, p<0.001), 13% in males (95% CI: 7%-18%; I2 = 96.0%, p<0.001), and 5% in females (95% CI: 3%-7%; I2 = 73.3%, p = 0.01). The pooled prevalence of moderate-to-severe OSA (AHI ≥15 events/hour) was 5% (95% CI: 2%-8%, I2 = 95.3%; p = 0.01). Based on these findings, approximately 104 million Indians of working age suffer from OSA, of whom 47 million have moderate-to-severe OSA. This represents a major public health problem in India with important implications for the global burden of the disease.

Effectiveness and feasibility of continuous positive airway pressure in patients with stroke and sleep apnea: a meta-analysis of randomized trials

STUDY OBJECTIVES

This meta-analysis aimed to investigate the feasibility and effectiveness of continuous positive airway pressure (CPAP) treatment in stroke patients with sleep apnea.

METHODS

PubMed, EMBASE, and the Cochrane Library were searched from inception until July 28, 2022, for randomized controlled trials comparing the use of CPAP and usual treatment in patients with stroke or transient ischemic attack and sleep apnea. The primary outcome measures were the feasibility of CPAP therapy, neurological function, and functional status.

RESULTS

After screening 5,747 studies, 14 studies with 1,065 patients were included in this meta-analysis. Overall, 8 of the 14 studies recorded CPAP use, and the mean CPAP use was 4.47 hours per night (95% confidence interval [CI]: 3.85-5.09). The risk ratio of discontinuing CPAP was 1.50 (95% CI: 0.76-2.94; P = .24). Analysis of the neurofunctional scales showed that CPAP treatment improved neurological function (standardized mean difference: 0.28; 95% CI: 0.02-0.53), but there was substantial heterogeneity (I2 = 57%, P = .03) across the studies. CPAP treatment had no significant effect on functional status vs the control (standardized mean difference: 0.25; 95% CI: -0.01 to 0.51), but the studies also had substantial heterogeneity (I2 = 55%, P = .06).

CONCLUSIONS

CPAP treatment is feasible in patients with stroke and sleep apnea and may improve neurological outcomes in these patients. However, this finding should be interpreted with caution because of the substantial heterogeneity of current trials.

CITATION

Fu S, Peng X, Li Y, Yang L, Yu H. Effectiveness and feasibility of continuous positive airway pressure in patients with stroke and sleep apnea: a meta-analysis of randomized trials. J Clin Sleep Med. 2023;19(9):1685-1696.

Stroke: What's Sleep Got to Do With It?

SUMMARY

Ischemic strokes most often occur between 6 am and 12 am after awakening from sleep but up to 30% occur during sleep. Wake-up strokes (WUS) are new focal neurological deficit(s) persisting for ≥ 24 hours attributable to an ischemic event present on patient awakening. Obstructive sleep apnea (OSA) is a major risk factor for WUS because it compounds the instability of the morning environment and increases the likelihood of cardiovascular events, including hypertension, atrial fibrillation, right-to-left shunts, and stroke. Circadian-driven alterations in structural, homeostatic, and serological factors also predispose to WUS. Also, WUS patients are often not considered candidates for time-dependent intravenous thrombolysis therapy because of an uncertain onset time. However, using the tissue clock (positive diffusion weighted imaging-negative fluid-attenuated inversion recovery mismatch) dates the WUS as 3 to 4.5 hours old and permits consideration for intravenous thrombolysis and if needed mechanical thrombectomy. Given the high prevalence of moderate/severe OSA in stroke patients and its impact on stroke outcomes, screening with overnight pulse oximetry and home sleep apnea test is needed. Treating OSA poststroke remains challenging. Polysomnographic changes in sleep architecture following acute/subacute stroke may also impact upon stroke outcome.

Global burden of sleep-disordered breathing and its implications

One-seventh of the world's adult population, or approximately one billion people, are estimated to have OSA. Over the past four decades, obesity, the main risk factor for OSA, has risen in striking proportion worldwide. In the past 5 years, the WHO estimates global obesity to affect almost two billion adults. A second major risk factor for OSA is advanced age. As the prevalence of the ageing population and obesity increases, the vulnerability towards having OSA increases. In addition to these traditional OSA risk factors, studies of the global population reveal select contributing features and phenotypes, including extreme phenotypes and symptom clusters that deserve further examination. Untreated OSA is associated with significant comorbidities and mortality. These represent a tremendous threat to the individual and global health. Beyond the personal toll, the economic costs of OSA are far-reaching, affecting the individual, family and society directly and indirectly, in terms of productivity and public safety. A better understanding of the pathophysiology, individual and ethnic similarities and differences is needed to better facilitate management of this chronic disease. In some countries, measures of the OSA disease burden are sparse. As the global burden of OSA and its associated comorbidities are projected to further increase, the infrastructure to diagnose and manage OSA will need to adapt. The use of novel approaches (electronic health records and artificial intelligence) to stratify risk, diagnose and affect treatment are necessary. Together, a unified multi-disciplinary, multi-organizational, global approach will be needed to manage this disease.

Recognition and treatment of sleep-disordered breathing: an important component of chronic disease management

Sleep-disordered breathing (SDB) is a highly prevalent condition, and is associated with many debilitating chronic diseases. The role of untreated obstructive sleep apnea (OSA) in arterial hypertension has been recognized in international guidelines. Treatment with continuous positive airway pressure (CPAP) is associated with clinically-relevant reductions in blood pressure. In heart failure (HF), SDB is associated with worse prognosis and increased mortality. Major HF guidelines recommend that patients should be treated for sleep apnea to improve their HF status. Severe OSA increases the risk of arrhythmias, including atrial fibrillation, influences risk management in stroke, and is highly prevalent in patients with type 2 diabetes. Effective treatment with CPAP improves the success of antiarrhythmic interventions, improves outcomes in stroke and reduces hyperglycemia in diabetes. Patients with coronary artery disease also have a high prevalence of SDB, which is independently associated with worse outcomes. The role of CPAP for secondary cardiovascular prevention remains to be determined. Data from large, well-conducted clinical trials have shown that noninvasive ventilation, targeted to markedly reduce hypercapnia, significantly improves survival and reduces readmission in stable hypercapnic chronic obstructive pulmonary disease. The association of SDB with chronic diseases contributes to the high healthcare costs incurred by SDB patients. SDB also has an important negative impact on quality of life, which is reversed by CPAP treatment. The high prevalence of SDB, and its association with diseases that cause significant morbidity and mortality, suggest that the diagnosis and management of SDB is an important therapeutic goal. First, adherent CPAP treatment significantly improves the quality of life of all patients with SDB; second, it eliminates the negative impact of untreated SDB on any associated chronic diseases; and third, it significantly reduces the increased costs of all hospital and medical services directly associated with untreated SDB. In short, the recognition and treatment of SDB is vital for the continued health and wellbeing of individual patients with SDB.