title: Microcirculatory rarefaction in South Asians - a potential mechanism for increased cardiovascular risk and diabetes.
abstract: People of South Asian descent have an increased risk of cardiovascular disease (CVD) and diabetes, but little is known about the microcirculation in South Asian people despite evidence that this plays an important role in the aetiology of CVD. We compared the retinal microcirculation in a population-based sample of 287 middle-aged adults (144 European 143 South Asian) matched for age and sex. Retinal photographs were taken and analysed using a validated semi-automated program and microvascular measures were compared. Blood pressure, anthropometry and fasting bloods were also measured. South Asians had significantly fewer arteriolar and venular vessels and bifurcations. Arterioles and venules were longer and venules were also more tortuous in South Asians. These differences were not explained by adjustment for traditional risk factors including blood pressure, body mass index, diabetes or measures of insulin resistance. People of South Asian descent have rarefaction of the retinal microcirculation compared to age-sex matched individuals of European descent. Reduced microvascular density could contribute to the elevated risk of CVD and impaired glucose tolerance in South Asian people.
authors.affiliation: International Centre for Circulatory Health, NHLI Division, Faculty of Medicine, Imperial College London and Imperial College Healthcare NHS Trust, London, United Kingdom.
authors.forename: Alun D
authors.initials: AD
authors.lastname: Hughes
authors.forename: Raj
authors.initials: R
authors.lastname: Bathula
authors.forename: Chloe
authors.initials: C
authors.lastname: Park
authors.forename: Therese
authors.initials: T
authors.lastname: Tillin
authors.forename: Nicholas
authors.initials: N
authors.lastname: Wit
authors.forename: Simon
authors.initials: S
authors.lastname: McG Thom
authors.forename: Nish
authors.initials: N
authors.lastname: Chaturvedi
mesh_terms: D000368:Aged; D001160:Arterioles / Q000473:pathology / Q000503:physiopathology; D044466:Asian People / Q000706:statistics & numerical data; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000097:blood / Q000208:ethnology / Q000503:physiopathology*; D003920:Diabetes Mellitus / Q000097:blood / Q000208:ethnology / Q000503:physiopathology*; D005215:Fasting / Q000097:blood; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D008833:Microcirculation; D008875:Middle Aged; D015999:Multivariate Analysis; D012044:Regression Analysis; D012171:Retinal Vessels / Q000473:pathology / Q000503:physiopathology*; D018570:Risk Assessment / Q000379:methods / Q000706:statistics & numerical data; D012307:Risk Factors; D014699:Venules / Q000473:pathology / Q000503:physiopathology; D044465:White People / Q000706:statistics & numerical data
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007328:Insulin; D008055:Lipids