Common carotid intima-media thickness measurements in cardiovascular risk prediction: a meta-analysis.
BACKGROUND
The evidence that measurement of the common carotid intima-media thickness (CIMT) improves the risk scores in prediction of the absolute risk of cardiovascular events is inconsistent.


OBJECTIVE
To determine whether common CIMT has added value in 10-year risk prediction of first-time myocardial infarctions or strokes, above that of the Framingham Risk Score.


METHODS
Relevant studies were identified through literature searches of databases (PubMed from 1950 to June 2012 and EMBASE from 1980 to June 2012) and expert opinion.


METHODS
Studies were included if participants were drawn from the general population, common CIMT was measured at baseline, and individuals were followed up for first-time myocardial infarction or stroke.


METHODS
Individual data were combined into 1 data set and an individual participant data meta-analysis was performed on individuals without existing cardiovascular disease.


RESULTS
We included 14 population-based cohorts contributing data for 45,828 individuals. During a median follow-up of 11 years, 4007 first-time myocardial infarctions or strokes occurred. We first refitted the risk factors of the Framingham Risk Score and then extended the model with common CIMT measurements to estimate the absolute 10-year risks to develop a first-time myocardial infarction or stroke in both models. The C statistic of both models was similar (0.757; 95% CI, 0.749-0.764; and 0.759; 95% CI, 0.752-0.766). The net reclassification improvement with the addition of common CIMT was small (0.8%; 95% CI, 0.1%-1.6%). In those at intermediate risk, the net reclassification improvement was 3.6% in all individuals (95% CI, 2.7%-4.6%) and no differences between men and women.


CONCLUSIONS
The addition of common CIMT measurements to the Framingham Risk Score was associated with small improvement in 10-year risk prediction of first-time myocardial infarction or stroke, but this improvement is unlikely to be of clinical importance.
Julius Center for Health Sciences and Primary Care, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands. hruijte2@umcutrecht.nl
Hester M
HM
Den Ruijter
Sanne A E
SA
Peters
Todd J
TJ
Anderson
Annie R
AR
Britton
Jacqueline M
JM
Dekker
Marinus J
MJ
Eijkemans
Gunnar
G
Engström
Gregory W
GW
Evans
Jacqueline
J
de Graaf
Diederick E
DE
Grobbee
Bo
B
Hedblad
Albert
A
Hofman
Suzanne
S
Holewijn
Ai
A
Ikeda
Maryam
M
Kavousi
Kazuo
K
Kitagawa
Akihiko
A
Kitamura
Hendrik
H
Koffijberg
Eva M
EM
Lonn
Matthias W
MW
Lorenz
Ellisiv B
EB
Mathiesen
Giel
G
Nijpels
Shuhei
S
Okazaki
Daniel H
DH
O'Leary
Joseph F
JF
Polak
Jackie F
JF
Price
Christine
C
Robertson
Christopher M
CM
Rembold
Maria
M
Rosvall
Tatjana
T
Rundek
Jukka T
JT
Salonen
Matthias
M
Sitzer
Coen D A
CD
Stehouwer
Jacqueline C
JC
Witteman
Karel G
KG
Moons
Michiel L
ML
Bots
D002318:Cardiovascular Diseases / Q000453:epidemiology*; D059168:Carotid Intima-Media Thickness; D015331:Cohort Studies; D006801:Humans; D009203:Myocardial Infarction / Q000453:epidemiology; D011237:Predictive Value of Tests; D018570:Risk Assessment; D020521:Stroke / Q000453:epidemiology