Can metabolic syndrome usefully predict cardiovascular disease and diabetes? Outcome data from two prospective studies.
BACKGROUND
Clinical use of criteria for metabolic syndrome to simultaneously predict risk of cardiovascular disease and diabetes remains uncertain. We investigated to what extent metabolic syndrome and its individual components were related to risk for these two diseases in elderly populations.


METHODS
We related metabolic syndrome (defined on the basis of criteria from the Third Report of the National Cholesterol Education Program) and its five individual components to the risk of events of incident cardiovascular disease and type 2 diabetes in 4812 non-diabetic individuals aged 70-82 years from the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER). We corroborated these data in a second prospective study (the British Regional Heart Study [BRHS]) of 2737 non-diabetic men aged 60-79 years.


RESULTS
In PROSPER, 772 cases of incident cardiovascular disease and 287 of diabetes occurred over 3.2 years. Metabolic syndrome was not associated with increased risk of cardiovascular disease in those without baseline disease (hazard ratio 1.07 [95% CI 0.86-1.32]) but was associated with increased risk of diabetes (4.41 [3.33-5.84]) as was each of its components, particularly fasting glucose (18.4 [13.9-24.5]). Results were similar in participants with existing cardiovascular disease. In BRHS, 440 cases of incident cardiovascular disease and 105 of diabetes occurred over 7 years. Metabolic syndrome was modestly associated with incident cardiovascular disease (relative risk 1.27 [1.04-1.56]) despite strong association with diabetes (7.47 [4.90-11.46]). In both studies, body-mass index or waist circumference, triglyceride, and glucose cutoff points were not associated with risk of cardiovascular disease, but all five components were associated with risk of new-onset diabetes.


CONCLUSIONS
Metabolic syndrome and its components are associated with type 2 diabetes but have weak or no association with vascular risk in elderly populations, suggesting that attempts to define criteria that simultaneously predict risk for both cardiovascular disease and diabetes are unhelpful. Clinical focus should remain on establishing optimum risk algorithms for each disease.
Sattar
Naveed
N
Faculty of Medicine, BHF Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK. nsattar@clinmed.gla.ac.uk
McConnachie
Alex
A
Shaper
A Gerald
AG
Blauw
Gerard J
GJ
Buckley
Brendan M
BM
de Craen
Anton J
AJ
Ford
Ian
I
Forouhi
Nita G
NG
Freeman
Dilys J
DJ
Jukema
J Wouter
JW
Lennon
Lucy
L
Macfarlane
Peter W
PW
Murphy
Michael B
MB
Packard
Chris J
CJ
Stott
David J
DJ
Westendorp
Rudi G
RG
Whincup
Peter H
PH
Shepherd
James
J
Wannamethee
S Goya
SG
D000368:Aged; D000369:Aged, 80 and over; D000924:Anticholesteremic Agents / Q000627:therapeutic use; D002318:Cardiovascular Diseases / Q000209:etiology*; D002784:Cholesterol / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000209:etiology*; D005260:Female; D005853:Geriatrics; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications*; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D017035:Pravastatin / Q000627:therapeutic use; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors
D000924:Anticholesteremic Agents; D002784:Cholesterol; D017035:Pravastatin