Waist circumference and insulin resistance in elderly men: an analysis of Kahrizak elderly study.
BACKGROUND
Diagnosis of the metabolic syndrome (MS) is crucial for health care practitioners to identify at risk people for early treatment. Visceral obesity may make unnecessary other laborious measures of insulin resistance. The aim of this study was to see whether waist circumference (WC) can predict insulin resistance as well as MS in a group of Iranian elderly.


METHODS
Out of 94 nondiabetic elderly, thirty three subjects were recognized with MS. MS diagnosis was based on NCEP ATP III (National Cholesterol Education Program Adult Treatment Panel III) and IDF (International Diabetes Federation) definitions. HOMA (Homeostasis Model Assessment) index was used to measure insulin sensitivity. Insulin resistance (IR) was defined as top quartile of HOMA.


RESULTS
In both sexes, WC and HOMA index were significantly positively correlated. The optimal waist circumference (OWC) cutoff point was 94.5 cm for men and 90.5 cm for women. The high sensitivity (0.80) and specificity (0.84) of WC in males indicates the proportion of IR which is correctly identified and recognizes all non-IR males as such. In regression model only the TG level was associated with WC. But the WC is strongly associated with HOMA-IR.


CONCLUSIONS
While OWC is very likely a good measure to exclude non-IR subjects in our study, determination of optimal WC to identify elderly IR subjects warrants further study in a larger sample of the general population.
Mojdeh
M
Mirarefin
Farshad
F
Sharifi
Hossein
H
Fakhrzadeh
Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran, Iran. mramini@tums.ac.ir.
Mohammad Reza
MR
Amini
Maryam
M
Ghaderpanahi
Nahid Zerafati
NZ
Shoa
Zohreh
Z
Badamchizadeh
Yaser
Y
Tajalizadekhoob
Neda
N
Nazari
Bagher
B
Larijani