The impact of ethnicity and sex on subclinical cardiovascular disease: the Diabetes Heart Study.
OBJECTIVE
African-Americans with type 2 diabetes and access to adequate healthcare are at lower risk of clinical coronary artery disease than are white diabetic patients. We evaluated whether ethnic differences in subclinical cardiovascular disease, coronary and carotid artery calcified plaque and carotid artery intima-medial thickness (IMT) were present in members of The Diabetes Heart Study families.


METHODS
In a bi-racial cohort of 1,180 individuals from families enriched for members with type 2 diabetes, we calculated coronary and carotid artery calcified plaque using fast-gated helical computed tomography, and measured carotid artery IMT and clinical risk factor profiles. Generalised estimating equations were used to test for an association between measures of subclinical cardiovascular disease and ethnicity and sex.


RESULTS
After adjustment for age, ethnicity and kidney function, African-Americans had significantly lower amounts of coronary artery calcified plaque (mean+/-SE) (866+/-158 vs 1,915+/-135, respectively; p=0.0466) and carotid artery calcified plaque (179+/-51 vs 355+/-27, respectively; p=0.0240) relative to whites, despite having increased carotid IMT (0.71+/-0.01 vs 0.67+/-0.004 cm, respectively; p=0.0007), and higher blood pressure, albuminuria and HbA1c. Sex-specific analyses revealed that African-American men had significantly lower coronary and carotid artery calcified atheroma than white men. In women, ethnic differences in calcified carotid artery plaque, but not coronary artery plaque, were observed.


CONCLUSIONS
In families enriched for members with type 2 diabetes, African-American men had markedly lower levels of coronary and carotid artery calcified plaque than white men, despite increased carotid artery IMT and conventional risk factors. These findings suggest that susceptibility to subclinical cardiovascular disease differs markedly according to ethnicity and sex.
Freedman
B I
BI
Wake Forest University School of Medicine, Department of Internal Medicine/Section on Nephrology, Medical Center Boulevard, 27157-1053, Winston-Salem, NC 27157-1053, USA. bfreedma@wfubmc.edu
Hsu
F C
FC
Langefeld
C D
CD
Rich
S S
SS
Herrington
D M
DM
Carr
J J
JJ
Xu
J
J
Bowden
D W
DW
Wagenknecht
L E
LE
D000328:Adult; D001741:Black or African American; D000368:Aged; D002318:Cardiovascular Diseases / Q000453:epidemiology* / Q000208:ethnology* / Q000209:etiology / Q000503:physiopathology; D002339:Carotid Arteries / Q000473:pathology; D016893:Carotid Stenosis / Q000453:epidemiology / Q000208:ethnology / Q000473:pathology; D015331:Cohort Studies; D003331:Coronary Vessels / Q000473:pathology; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000453:epidemiology / Q000208:ethnology* / Q000503:physiopathology; D003925:Diabetic Angiopathies / Q000453:epidemiology* / Q000208:ethnology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012727:Sex Characteristics; D036542:Tomography, Spiral Computed; D017539:Tunica Intima / Q000473:pathology; D044465:White People