Diagnosis of insulin resistance in hypertensive patients by the metabolic syndrome: AHA vs. IDF definitions.
BACKGROUND
Subjects with the metabolic syndrome are accompanied by insulin resistance (IR). However, it is not clear how well the newly defined metabolic syndrome identifies IR specifically in hypertensive subjects.


OBJECTIVE
The purpose of the study was to evaluate the performance of the metabolic syndrome, defined by the American Heart Association (AHA) and the International Diabetes Federation (IDF) definitions, in identifying IR in hypertension.


METHODS
The analysis is a cross-sectional study. Totally, 228 hypertensive patients and 92 non-diabetic normotensive controls who received insulin suppressive tests for direct evaluation of their insulin sensitivity were included from the Stanford Asia and Pacific Program for Hypertension and IR. McNemar's tests were used to compare sensitivity and specificity of the AHA-defined with the IDF-defined metabolic syndrome in diagnosis of IR.


RESULTS
The sensitivity of the metabolic syndrome for IR in hypertension was 89.7% and the specificity 45.9% by the AHA definition. Using the IDF definition, the sensitivity was 77.6%, and the specificity increased to 63.5%. The diagnostic power of individual components of the syndrome was also modest. The predictive discrimination of wider waist circumference was similar to that of the AHA-defined metabolic syndrome.


CONCLUSIONS
Use of the metabolic syndrome by the AHA definition provided good sensitivity, but low specificity to diagnose IR in hypertension. The IDF definition improved in false-positive rate, but it was still not specific enough to identify IR in hypertension.
Section of General Medicine, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan. chhwu@vghtpe.gov.tw
C-M
CM
Hwu
C A
CA
Hsiung
K-D
KD
Wu
W-J
WJ
Lee
K-C
KC
Shih
J
J
Grove
Y-D I
YD
Chen
B L
BL
Rodriguez
J D
JD
Curb
D000328:Adult; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications*; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000175:diagnosis*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D055105:Waist Circumference