title: Altered plasma fibrin clot properties in hypertensive patients with obstructive sleep apnoea are improved by continuous positive airway pressure treatment.
abstract: We investigated plasma fibrin clot properties in high-risk hypertensive patients with obstructive sleep apnoea (OSA) and assessed the impact of continuous positive airway pressure (CPAP) treatment on clot phenotype.
  
  
  
  We studied 50 hypertensive patients with clinically significant OSA (age 50.0 ± 8.8 years, 39 M, 11 F). In total, 38 hypertensive patients without OSA balanced for age, sex, blood pressure, cardiovascular risk factors, and metabolic status served as controls. Plasma fibrin clot properties, including clot permeability coefficient, clot lysis time (CLT), and turbidimetric parameters of clot formation were determined. Patients underwent transthoracic echocardiography, carotid ultrasonography, evaluation of endothelial function and calcium score index of coronary arteries, and Doppler imaging of renal arteries.
  
  
  
  Compared with controls, OSA patients were characterized by more compact fibrin structure (lower median clot permeability coefficient, 6.00 vs. 7.25 10 cm; P < 0.001), impaired fibrinolysis (longer median CLT, 108.00 vs. 92.50 min; P < 0.001), and by faster clot formation (shorter median lag phase, 40.50 vs. 42.50 s; P = 0.041), and higher median maximum clot absorbency indicating denser fibrin networks (0.87 vs. 0.81; P = 0.028). Clot permeability coefficient and CLT correlated with apnoea-hypopnoea index (r = -0.46; P < 0.001 and r = 0.44; P < 0.001, respectively) as well with mean (r = 0.31; P = 0.003; r = -0.36; P = 0.001, respectively) and minimal oxygen saturation (r = 0.46; P < 0.001; r = -0.49; P < 0.001, respectively). After 3 months of CPAP treatment we observed an increase in clot permeability coefficient (5.95 vs. 7.60 10 cm; P = 0,001), shortened CLT (107.00 vs. 87.00; P = 0.006), a longer lag phase of fibrin formation (40.00 vs. 43.50 s; P = 0.013), and a trend toward lower maximum clot absorbency (0.86 vs. 0.81; P = 0.058).
  
  
  
  In hypertensive patients at high cardiovascular risk, OSA was associated with unfavourable prothrombotic fibrin clot characteristics, including hypofibrinolysis, which significantly improve as early as after 3 months of CPAP treatment.
authors.affiliation: aDepartment of Hypertension, Institute of Cardiology, Warsaw bInstitute of Cardiology, Jagiellonian University Medical College cInnovative Laboratory Diagnostic Centre, John Paul II Hospital, Kraków dII Department of Radiology, Medical University of Warsaw e2nd Department of Respiratory Medicine, Institute of Tuberculosis and Lung Disease fDepartment of Coronary and Structural Heart Diseases, Institute of Cardiology gDepartment of Congenital Heart Diseases, Institute of Cardiology, Warsaw hCracow Centre for Medical Research and Technologies, John Paul II Hospital, Kraków, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Jóźwik-Plebanek
authors.forename: Aleksander
authors.initials: A
authors.lastname: Prejbisz
authors.forename: Ewa
authors.initials: E
authors.lastname: Wypasek
authors.forename: Barbara
authors.initials: B
authors.lastname: Pręgowska-Chwała
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Hanus
authors.forename: Anna M
authors.initials: AM
authors.lastname: Kaszuba
authors.forename: Magdalena
authors.initials: M
authors.lastname: Januszewicz
authors.forename: Przemysław
authors.initials: P
authors.lastname: Bieleń
authors.forename: Marek
authors.initials: M
authors.lastname: Kabat
authors.forename: Mariusz
authors.initials: M
authors.lastname: Kruk
authors.forename: Piotr
authors.initials: P
authors.lastname: Dobrowolski
authors.forename: Anna
authors.initials: A
authors.lastname: Klisiewicz
authors.forename: Paweł
authors.initials: P
authors.lastname: Śliwiński
authors.forename: Andrzej
authors.initials: A
authors.lastname: Januszewicz
authors.forename: Anetta
authors.initials: A
authors.lastname: Undas
mesh_terms: D000328:Adult; D000368:Aged; D002339:Carotid Arteries / Q000000981:diagnostic imaging; D045422:Continuous Positive Airway Pressure; D004452:Echocardiography; D005260:Female; D005337:Fibrin / Q000378:metabolism*; D063285:Fibrin Clot Lysis Time; D005342:Fibrinolysis; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000150:complications; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D010539:Permeability; D012077:Renal Artery / Q000000981:diagnostic imaging; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000150:complications / Q000628:therapy*; D013927:Thrombosis / Q000097:blood / Q000378:metabolism*; D018608:Ultrasonography, Doppler
chemical_list: D005337:Fibrin; D010100:Oxygen