Evaluation of the association between sleep apnea and polyunsaturated fatty acids profiles in patients after percutaneous coronary intervention

Plasma polyunsaturated fatty acid concentrations and sleep apnea risk: A two-sample Mendelian randomization study

Background

Previous observational studies have found that lower levels of circulating polyunsaturated fatty acids (PUFAs) were associated with a higher risk of sleep apnea (SA). However, the causality of the association remains unclear.

Materials and methods

We used the two-sample Mendelian randomization (MR) study to assess the causal association of omega-3 and omega-6 fatty acids with SA. Single-nucleotide polymorphisms (SNPs) predicting the plasma level of PUFAs at the suggestive genome-wide significance level (p < 5 × 10^–6) were selected as instrumental variables (IVs) from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) (n = ∼8,000) Consortium. For outcomes, the summary-level statistics of SA were obtained from the latest genome-wide association study (GWAS), which combined five cohorts with a total number of 25,008 SA cases and 172,050 snoring cases (total = 523,366).

Results

We found no association of α-linolenic acid (ALA) [odds ratio (OR) = 1.09 per% changed, 95% confidence interval (CI) 0.67–1.78], eicosapentaenoic acid (EPA) (OR = 0.94, 95% CI 0.88–1.01), docosapentaenoic acid (DPA) (OR = 0.95, 95% CI 0.88–1.02), and docosahexaenoic acid (DHA) (OR = 0.99, 95% CI 0.96–1.02) with the risk of SA using inverse-variance weighted (IVW) method. Moreover, for omega-6 PUFAs, no association between linoleic acid (LA) (OR = 0.98, 95% CI 0.96–1.01), arachidonic acid (AA) (1.00, 95% CI 0.99–1.01), and adrenic acid (AdrA) (0.93, 95% CI 0.71–1.21) with the risk of SA was found. Similarly, no associations of PUFAs with SA were found in single-locus MR analysis.

Conclusion

In the current study, we first found that there is no genetic evidence to support the causal role of omega-3 and omega-6 PUFAs in the risk of SA. From a public health perspective, our findings refute the notion that consumption of foods rich in PUFAs or the use of PUFAs supplementation can reduce the risk of SA.

Crossover comparison between CPAP and mandibular advancement device with adherence monitor about the effects on endothelial function, blood pressure and symptoms in patients with obstructive sleep apnea

Mandibular advancement device (MAD) is an alternative therapeutic option for CPAP to treat obstructive sleep apnea (OSA). While MAD showed the better adherence, patients with over moderate OSA have been treated more frequently with CPAP despite increasing positive evidence on the cardiovascular outcome with MAD, even in severe patients. Thus, more information is needed regarding the cardiovascular and symptomatic outcome of MAD treatment objectively compared to CPAP. Forty-five supine-dependent OSA patients (apnea-hypopnea index 20-40/h) were randomized to either CPAP or MAD and treated for 8 weeks and switched to another for 8 weeks. The primary endpoint was improvement in the endothelial function, indexed by the flow-mediated dilatation (FMD), and the secondary endpoint was the sleep-time blood pressure (BP). The duration of MAD use was evaluated objectively by an implanted adherence monitor. Treatment efficacy was also evaluated by home sleep monitor and a questionnaire about the symptoms. The adherence was not significantly different (CPAP vs. MAD: 274.5 ± 108.9 min/night vs. 314.8 ± 127.0 min/night, p = 0.095). FMD and sleep-time mean BP were not markedly changed from the baseline with either approach (CPAP vs. MAD: FMD, + 0.47% ± 3.1% vs. + 0.85% ± 2.6%, p = 0.64; BP, - 1.5 ± 5.7 mmHg vs. - 1.2 ± 7.5 mmHg, p = 0.48), although sleepiness, nocturia, and sleep-related parameters were similarly improved and more patients preferred MAD. As MAD and CPAP showed similar effects on cardiovascular outcome and symptomatic relief even with a comparable length of usage, we might expect MAD as an alternative treatment option for CPAP in this range of OSA group.