Effects of recombinant human IGF-I and oral contraceptive administration on bone density in anorexia nervosa.
Over 90% of women with anorexia nervosa demonstrate osteopenia, and almost 40% demonstrate osteoporosis at one or more skeletal sites. In addition to estrogen deficiency causing an increase in bone resorption, nutritional effects on the GH-IGI-I axis may contribute to the severe bone loss in this population by decreasing bone formation. We tested the hypothesis that recombinant human IGF-I (rhIGF-I) would increase bone density in women with anorexia nervosa and furthermore assessed the effects of combined rhIGF-I and oral contraceptive administration (OCP) in this population. Sixty osteopenic women with Diagnosis and Statistical Manual of Mental Disorders IV Revised confirmed anorexia nervosa [age (25.2 +/- 0.7 yr, range 18-38 yr), body mass index (17.8 +/- 0.3 kg/m(2) ), spinal bone mineral density T score (-2.1 +/- 0.1 SD) were randomized to one of four treatment groups [rhIGF-I (30 microg/kg sc twice daily) and a daily oral contraceptive (Ovcon 35, 35 microg ethinyl estradiol and 0.4 mg norethindrone], rhIGF-I alone (30 microg/kg sc twice daily), oral contraceptive alone, or neither treatment for 9 months. All subjects received calcium 1500 mg/d and a standard multivitamin containing 400 IU of vitamin D. Administration of rhIGF-I was placebo controlled and blinded to subjects. The rhIGF-I was titrated to maintain IGF-I levels within the age-adjusted normal range for each patient and was well tolerated. The effects of rhIGF-I and OCP were analyzed simultaneously among all subjects in a factorial analysis and in an analysis of the four individual treatment groups. Anteroposterior spinal bone density increased significantly in response to rhIGF-I (1.1% +/- 0.5% vs. -0.6% +/- 0.8%, P = 0.05, all rhIGF-I vs. all placebo treated, respectively, by analysis of covariance). In contrast, OCP did not result in increased bone density (0.8% +/- 0.6% vs. -0.4% +/- 0.8%, P = 0.21, all OCP vs. all non-OCP treated, respectively, by analysis of covariance). However, bone density increased to the greatest extent in the combined treatment group (rhIGF-I and OCP), compared with control patients receiving no active therapy (1.8% +/- 0.8% vs. 0.3% +/- 0.6% vs. -0.2% +/- 0.8% vs. -1.0% +/- 1.3%, rhIGF-I and OCP vs. rhIGF-I alone vs. OCP alone vs. no active therapy, P < 0.05 for rhIGF-I and OCP vs. no active therapy). These data demonstrate that osteopenic women with anorexia nervosa treated with rhIGF-I showed more beneficial changes in bone density, compared with patients not treated with rhIGF-I. Antiresorptive therapy with OCP is not sufficient to improve bone density in undernourished patients, but such therapy may augment the effects of rhIGF-I in a combined treatment strategy. Further long-term studies are needed to investigate the effects of rhIGF-I and combined anabolic/antiresorptive strategies on bone in women with anorexia nervosa.
Grinspoon
Steven
S
Neuroendocrine Unit, Massachusetts General Hospital, Boston, MA 02114, USA. sgrinspoon@partners.org
Thomas
Lisa
L
Miller
Karen
K
Herzog
David
D
Klibanski
Anne
A
D000328:Adult; D000856:Anorexia Nervosa / Q000188:drug therapy* / Q000378:metabolism*; D015415:Biomarkers; D015519:Bone Density / Q000187:drug effects*; D016723:Bone Remodeling / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D003276:Contraceptives, Oral / Q000009:adverse effects / Q000627:therapeutic use*; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D004997:Ethinyl Estradiol / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000009:adverse effects / Q000627:therapeutic use*; D009640:Norethindrone / Q000627:therapeutic use*; D011994:Recombinant Proteins / Q000627:therapeutic use; D012016:Reference Values
D015415:Biomarkers; D003276:Contraceptives, Oral; D004338:Drug Combinations; D011994:Recombinant Proteins; D004997:Ethinyl Estradiol; D007334:Insulin-Like Growth Factor I; D002118:Calcium; D009640:Norethindrone