One-hour post-load plasma glucose and IGF-1 in hypertensive patients.
BACKGROUND
In normoglucose-tolerant subjects (NGT), 1-h post-load plasma glucose value ≥155 mg/dL, during an oral glucose tolerance test (OGTT), is associated with an increased risk of type-2 diabetes (T2D) and subclinical organ damage. Insulin-like growth factor-1 (IGF-1) is involved in the pathogenesis of insulin resistance (IR) and T2D. Moreover, hypertensives have different degrees of IR and different levels of IGF-1. Actually, there are no data supporting the association between post-load glucose and IGF-1; thus, the aim of the study was to investigate this relationship.


METHODS
We enrolled 1126 never-treated hypertensive subjects who underwent an OGTT and clinical characterization. Insulin sensitivity was assessed by the Matsuda index. IGF-1 was measured by a sensitive immunoradiometric assay.


RESULTS
Among participants, 764 had NGT, 263 had impaired glucose tolerance (IGT) and 99 had T2D. According to the 1-h post-load plasma glucose cut-off point of 155 mg/dL, we divided NGT subjects into NGT < 155 mg/dL and NGT ≥ 155 mg/dL. NGT ≥ 155 in comparison with NGT < 155 had significantly reduced insulin sensitivity and IGF-1 levels. At multiple regression analysis, IGF-1 was the major determinant of 1-h post-load glucose in NGT ≥ 155 subjects, IGT and diabetics, accounting for 20·9%, 17·7% and 15·5% of its variation in the respective models.


CONCLUSIONS
In hypertensive NGT ≥ 155 subjects, IGF-1 results strongly associated with 1-h post-load glucose, similarly to that observed in IGT and diabetics. This finding has clinical relevance because both low IGF-1 levels and 1-h post-load glucose in NGT subjects are associated with subclinical organ damage, an independent predictor of cardiovascular events.
Department of Medical and Surgical Sciences, University Magna Graecia of Catanzaro, Catanzaro, Italy. perticone@unicz.it
Francesco
F
Perticone
Angela
A
Sciacqua
Eliezer J
EJ
Tassone
Sofia
S
Miceli
Raffaele
R
Maio
Desirée
D
Addesi
Tania
T
Falbo
Franco
F
Arturi
Giorgio
G
Sesti
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D003430:Cross-Sectional Studies; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000378:metabolism* / Q000503:physiopathology; D007333:Insulin Resistance; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D013997:Time Factors; D044465:White People
D001786:Blood Glucose; D007334:Insulin-Like Growth Factor I