Serum insulin-like growth factor-I is a marker for assessing the severity of vertebral fractures in postmenopausal women with type 2 diabetes mellitus.
Although previous studies indicated that serum insulin-like growth factor-I (IGF-I) was inversely associated with the presence of vertebral fractures (VFs), little is known whether serum IGF-I is associated with multiple VFs. We report that serum IGF-I could be clinically useful for assessing the severity of VFs in type 2 diabetic postmenopausal women.


BACKGROUND
The number of VFs is associated with the mobility and mortality of the elderly people. Although serum IGF-I is inversely associated with the presence of VFs, little is known about the relationship between serum IGF-I and multiple VFs.


METHODS
In this cross-sectional study, we recruited 479 men and 334 postmenopausal women with type 2 diabetes mellitus and measured serum IGF-I, bone mineral density, and bone turnover markers. Lateral X-ray films of the thoracic and lumbar spine were taken to diagnose the VF.


RESULTS
In postmenopausal women, serum IGF-I level was decreased when the number of VFs was increased [no VFs; 138 ± 51 ng/ml (mean ± SD) vs. one VF; 119 ± 42 (p = 0.006), two VFs; 103 ± 39 (p = 0.002), and three and more VFs; 91 ± 40 (p < 0.001)]. Multiple logistic regression analysis adjusted for age, duration of diabetes, body mass index, serum creatinine, and HbA(1c) showed that serum IGF-I level was inversely associated with the presence of one VF [odds ratio (OR) = 0.67, p = 0.029], two VFs (OR = 0.40, p = 0.017), as well as three and more VFs (OR = 0.27, p = 0.005). These associations were still significant after the additional adjustment for BMD at the lumbar spine. In contrast, no significant association of serum IGF-I level with VFs was found in men.


CONCLUSIONS
Serum IGF-I level was inversely associated with the number of prevalent VFs in postmenopausal women with type 2 diabetes, suggesting that serum IGF-I could be clinically useful for assessing the severity of VFs in the population.
Kanazawa
I
I
Department of Internal Medicine 1, Shimane University Faculty of Medicine, 89-1 Enya-cho, Izumo, Shimane 693-8501, Japan. ippei.k@med.shimane-u.ac.jp
Yamaguchi
T
T
Sugimoto
T
T
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D015519:Bone Density / Q000502:physiology; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D058866:Osteoporotic Fractures / Q000097:blood / Q000209:etiology* / Q000503:physiopathology; D012737:Sex Factors; D016103:Spinal Fractures / Q000097:blood / Q000209:etiology* / Q000503:physiopathology
D015415:Biomarkers; D003404:Creatinine; D006442:Glycated Hemoglobin; D007334:Insulin-Like Growth Factor I