Cardiovascular risk markers in obstructive sleep apnoea syndrome and correlation with obesity

Background: High C-reactive protein (CRP) and homocysteine levels are risk factors for cardiovascular disease. Some, but not all, previous studies have reported increased levels of CRP and homocysteine in patients with obstructive sleep apnoea syndrome (OSAS). A study was undertaken to investigate t...

Full description

Saved in:

Bibliographic Details
Published in:	Thorax Vol. 62; no. 6; pp. 509 - 514
Main Authors:	Ryan, Silke, Nolan, Geraldine M, Hannigan, Evelyn, Cunningham, Sean, Taylor, Cormac, McNicholas, Walter T
Format:	Journal Article
Language:	English
Published:	London BMJ Publishing Group Ltd and British Thoracic Society 01-06-2007 BMJ BMJ Publishing Group LTD BMJ Group
Subjects:	Adult AHI apnoea-hypopnoea index Atherosclerosis (general aspects, experimental research) Biological and medical sciences Biomarkers - metabolism Blood and lymphatic vessels BMI Body mass index C-reactive protein C-Reactive Protein - metabolism Cardiology. Vascular system Cardiovascular disease Cardiovascular Diseases - etiology Cardiovascular Diseases - metabolism Case-Control Studies continuous positive airway pressure Coronary vessels CPAP CRP desaturation index Epworth Sleepiness Scale ESS Homocysteine Homocysteine - metabolism Humans Kruskal-Wallis test Laboratories Male Medical sciences Metabolic diseases Morbidity Obesity Obesity - complications Obesity - metabolism obstructive sleep apnoea syndrome OSAS Patients Pneumology polysomnography Positive-Pressure Respiration Prospective Studies PSG Respiratory system : syndromes and miscellaneous diseases Risk Factors Sleep apnea Sleep Apnea, Obstructive - complications Sleep Apnea, Obstructive - metabolism Sleep Apnea, Obstructive - therapy Sleep Disordered Breathing TNFα total sleep time TST Tumor necrosis factor-TNF tumour necrosis factor α Variables Variance analysis Vein & artery diseases Obesity Nervous system diseases Sleep apnea syndrome Correlation Respiratory disease Nutrition disorder Biological marker Cardiovascular disease Syndrome Vascular disease Atherosclerosis Risk factor Cardiovascular risk Nutritional status
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Background: High C-reactive protein (CRP) and homocysteine levels are risk factors for cardiovascular disease. Some, but not all, previous studies have reported increased levels of CRP and homocysteine in patients with obstructive sleep apnoea syndrome (OSAS). A study was undertaken to investigate the levels of these factors in carefully selected patients with OSAS and matched normal controls. Methods: CRP and homocysteine levels were measured in 110 subjects following polysomnography (PSG). Non-OSAS patients (group 1) were compared with two patient groups (mild/moderate OSAS (group 2) and severe OSAS (group 3)) group-matched for body mass index (BMI), and a fourth group of patients with severe OSAS who were more obese (group 4). All were free of other disease and similar in age, smoking habits and cholesterol levels. 50 suitable patients were commenced on continuous positive airway pressure (CPAP) treatment after PSG and 49 were reassessed 6 weeks later. Results: CRP levels were similar in groups 1, 2 and 3 (median (interquartile range (IQR)) 1.11 (0.76–2.11) mg/l vs 1.82 (1.20–3.71) mg/l vs 2.20 (1.16–3.59) mg/l; p = 0.727, Kruskal-Wallis test), but were significantly higher in group 4 than in the other groups (5.36 (2.42–9.17) mg/l, p<0.05 by individual group comparisons). In multivariate analysis of all subjects, BMI was an independent predictor for CRP levels (β = 0.221; p = 0.006) but apnoea-hypopnoea index and other measures of OSAS were not. There was no difference in homocysteine levels between all four groups (p = 0.1). CPAP did not alter CRP (2.29 (1.32–4.10) vs 2.84 (1.13–5.40) mg/l; p = 0.145) or homocysteine levels (8.49 (3.66) vs 9.90 (4.72) μmol/l; p = 0.381). Conclusion: CRP and homocysteine levels are not associated with OSAS severity in men but CRP is independently associated with obesity.
Bibliography:	PMID:17251313 href:thoraxjnl-62-509.pdf ark:/67375/NVC-N0NX6LNC-4 istex:CDCEB3ADB71657CD4BFE4E23981127FADEA5BD27 local:0620509 Correspondence to:  Professor W T McNicholas  Deprtment of Respiratory Medicine, St Vincent’s University Hospital, Elm Park, Dublin 4, Ireland; walter.mcnicholas@ucd.ie ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0040-6376 1468-3296
DOI:	10.1136/thx.2006.066720