Association between impaired insulin sensitivity and stroke.
BACKGROUND
Prior research has indicated an association between insulin resistance and stroke; we sought to determine if this association persists after adjusting for stroke risk factors, including glycemic control.


METHODS
We used data from the Third National Health and Nutrition Survey (1988-1994), including participants aged > or =40 years. We assessed insulin sensitivity using the homeostasis model assessment (HOMA): HOMA = (FPGSI x FPI)/22.5, where FPGSI refers to fasting plasma glucose (mmol/l) and FPI refers to fasting plasma insulin (microU/l). Increasing HOMA indicates decreasing insulin sensitivity. We used glycosylated hemoglobin (HbA1c) to measure glycemic control. Multivariable logistic regression analysis was used to identify factors that were independently associated with stroke.


RESULTS
Among 3,844 participants, 168 (4%) reported a stroke history. Participants with stroke had lower insulin sensitivity than participants without stroke: HOMA mean +/- standard deviation, 4.0 +/- 4.0 vs. 3.3 +/- 3.0; p = 0.022. HOMA was independently associated with stroke (odds ratio 1.06, 95% CI: 1.01-1.12; adjusted for age, hypertension, myocardial infarction, claudication, activity, and HbA1c). The strength of the association between HOMA and stroke was similar to the association between claudication and stroke (index R(2): 0.0032 vs. 0.0036).


CONCLUSIONS
Impaired insulin sensitivity is independently associated with stroke, even after adjustment for glycemic control.
Bravata
Dawn M
DM
Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT 06516, USA. Dawn.Bravata@yale.edu
Wells
Carolyn K
CK
Kernan
Walter N
WN
Concato
John
J
Brass
Lawrence M
LM
Gulanski
Barbara I
BI
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016021:Epidemiologic Studies; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006306:Health Surveys; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D020521:Stroke / Q000209:etiology*
D006442:Glycated Hemoglobin