Obstructive sleep apnea and hypertriglyceridaemia share common genetic background: Results of a twin study.

Obstructive sleep apnea is associated with an increased risk of hypertension, diabetes and dyslipidaemia. Both obstructive sleep apnea and its comorbidities are at least partly heritable, suggesting a common genetic background. Our aim was to analyse the heritability of the relationship between obstructive sleep apnea and its comorbidities using a twin study. Forty-seven monozygotic and 22 dizygotic adult twin pairs recruited from the Hungarian Twin Registry (mean age 51 ± 15 years) attended an overnight diagnostic sleep study. A medical history was taken, blood pressure was measured, and blood samples were taken for fasting glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and lipoprotein (a). To evaluate the heritability of obstructive sleep apnea and its comorbidities bivariate analysis was performed with an adjustment for age, gender, body mass index (BMI) and smoking after false discovery rate correction and following exclusion of patients on lipid-lowering and antidiabetic medications. There was a significant correlation between indices of obstructive sleep apnea severity, such as the apnea-hypopnea index, oxygen desaturation index and percentage of sleep time spent with oxygen saturation below 90%, as well as blood pressure, serum triglyceride, lipoprotein (a) and glucose levels (all p < .05). The bivariate analysis revealed a common genetic background for the correlations between serum triglyceride and the oxygen desaturation index (r = .63, p = .03), as well as percentage of sleep time spent with oxygen saturation below 90% (r = .58, p = .03). None of the other correlations were significantly genetically or environmentally determined. This twin study demonstrates that the co-occurrence of obstructive sleep apnea with hypertriglyceridaemia has a genetic influence and heritable factors play an important role in the pathogenesis of dyslipidaemia in obstructive sleep apnea.

Are the Variants of the Circle of Willis Determined by Genetic or Environmental Factors? Results of a Twin Study and Review of the Literature.

BACKGROUND: Anatomic variants of the circle of Willis (CW) are commonly observed in healthy subjects. Genetic and environmental factors influencing these variants remain unclear. Our aim was to assess the genetic and environmental background affecting variant CW phenotypes. METHODS: A total of 122 adult healthy twins from the Hungarian Twin Registry (39 monozygotic (MZ) and 22 dizygotic (DZ) pairs, average age 49.7 ± 13.4 years) underwent Time-of-Flight magnetic resonance angiography and transcranial Doppler sonography. We investigated the anterior and posterior CW according to morphological categories. Prevalence and concordance rates of CW variants were calculated. MZ twins discordant for CW variants were analyzed for cardiovascular risk factors and altered blood flow. RESULTS: Complete CW (45.0%) and bilaterally absent posterior communicating artery (PCoA) (22.5%) were the most prevalent variants in the anterior and posterior CW, respectively. There was no significant difference regarding the prevalence of variants across zygosity except for bilaterally hypoplastic PCoA (p = .02). DZ concordance was higher compared to MZ twins regarding morphological categories of the CW. Cardiovascular risk factors were not significantly associated with variant CW in MZ twins discordant to CW morphology. Flow parameters did not differ significantly among MZ twins discordant to CW variants. CONCLUSION: CW variants may not be determined by substantial genetic effects and are not influenced by altered blood flow in healthy individuals. Further investigations are needed to identify potential environmental factors affecting these variants.

Our initial experiences with MR arthrography / Kezdeti tapasztalataink az MR-artrográfiával.

INTRODUCTION: The gold standard method for shoulder surgery imaging is magnetic resonance imaging (MRI). The sensitivity of the conventional MRI for full thickness tears is way above 85%, for partial rotator cuff lesions this number is less than 40%. Diagnostic accuracy is equally low in detecting different variations of anterior labrum lesion and also in injury of the glenohumeral ligaments. Contrast agent given directly into the joint can improve these diagnostic inaccuracies. METHOD: We made the first shoulder joint related MR arthrography in February 2018 at the Semmelweis University. The studied period lasted for 17 months; during that time 29 examinations were performed. For the injection we used gadolinium-based contrast substance. RESULTS: In the case of 26 patients (89.9%), the contrast substance had a good position and distended well. From all of the shoulder MRI examinations, 9 (31%) surgical interventions were made, and 8 surgical findings had the same diagnosis as the radiologic description. CONCLUSION: The contrast substance given into the intraarticular space makes it easier to identify and detect the structures in the joint. The injection under X-ray screening is safe, it is absorbed from the joint in short time, and so far - based on our experience - there has not been any complication. It can help to identify injuries which are difficult to diagnose with conventional MRI, and helps planning before surgery. Orv Hetil. 2020; 161(36): 1514-1521.