Associations of insulin-like growth factor (IGF)-I, IGF-II, IGF binding protein (IGFBP)-2 and IGFBP-3 with ultrasound measures of atherosclerosis and plaque stability in an older adult population.

Abstract

CONTEXT:

Circulating IGF-I is inversely associated with ischemic heart disease incidence. Whether this association relates to alterations in plaque growth or stability, and the role of IGF-II and the major binding proteins [IGF binding protein (IGFBP)-2 and -3], is unclear.

OBJECTIVE:

Our objective was to test the hypothesis that circulating IGF-I is inversely, and IGF-II is positively, associated with subclinical atherosclerosis and plaque stability.

DESIGN, SETTING, AND PARTICIPANTS:

This was a cross-sectional analysis based on 310 participants in the United Kingdom-based Boyd Orr cohort who were aged 63-82 yr. Cohort members from Aberdeen, Bristol, Dundee, Wisbech, and London were invited to clinics for fasted venepuncture and arterial ultrasound examination.

MAIN OUTCOMES:

Arterial intima-media thickness, arterial plaque prevalence, and computerized assessment of plaque echogenicity (a measure of stability), undertaken using the gray scale median, were calculated.

RESULTS:

In total, 269 of 310 (86.8%) participants had at least one carotid or femoral plaque. In models controlling for IGFBP-3, there was a 44% (95% confidence interval 12-64%) reduction in the odds of any plaque and a 28% lower (0-48%) odds of echolucent (unstable) plaques per sd increase in IGF-I. IGFBP-3 was positively associated with plaque instability (odds ratio: 1.38; 0.99-1.93). IGF-II was positively associated (0.05-mm increase per sd; 95% confidence interval 0.01-0.09), and IGFBP-2 was inversely associated, with carotid bifurcation intima-media thickness. Neither IGF-II nor IGFBP-2 was associated with plaque prevalence or echogenicity.

CONCLUSION:

High-circulating IGF-I levels may promote arterial plaque stability. IGF-II and IGFBP-2 do not appear to play a role in plaque development or stability.

• Authors: Richard M Martin, David Gunnell, Elise Whitley, Andrew Nicolaides, Maura Griffin, Niki Georgiou, George Davey Smith, Shah Ebrahim, Jeff M P Holly
• Journal: The Journal of clinical endocrinology and metabolism (J Clin Endocrinol Metab) Vol. 93 Issue 4 Pg. 1331-8 (Apr 2008) ISSN: 0021-972X [Print] United States
• PMID: 18211967 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Insulin-Like Growth Factor Binding Protein 2
• Insulin-Like Growth Factor Binding Protein 3
• Insulin-Like Growth Factor I
• Insulin-Like Growth Factor II

Topics

• Aged
• Atherosclerosis (blood, diagnostic imaging)
• Cross-Sectional Studies
• Female
• Humans
• Insulin-Like Growth Factor Binding Protein 2 (blood)
• Insulin-Like Growth Factor Binding Protein 3 (blood)
• Insulin-Like Growth Factor I (analysis)
• Insulin-Like Growth Factor II (analysis)
• Male
• Middle Aged
• Tunica Intima (pathology)
• Tunica Media (pathology)
• Ultrasonography