Growth Hormone Administration and Its Effects on Cardiovascular Risk Factors in Growth Hormone Deficient Women

The purpose of the study is to evaluate the effects of growth hormone replacement on women with growth hormone deficiency. Growth hormone deficiency means the body no longer produces growth hormone due to a tumor or some kind of disease of the brain in an area called the pituitary/hypothalamic region. This is the area of the brain where growth hormone is normally produced. We, the researchers at Massachusetts General Hospital, will establish the effects of growth hormone replacement on cardiovascular parameters (laboratory tests, the flexibility of the arteries, changes in heart rate) in women with growth hormone deficiency. Our goal is to see if this therapy: * has effects on women's cardiovascular risk markers (special blood tests which indicate how healthy the heart and arteries are) * has effects on women's types and levels of various substances circulating in their blood * in women affects the stiffness of their arteries and heart rate variability in parallel with changes in cardiovascular risk markers * has different effects depending on whether women are pre or post menopausal. Participation in this study is expected to last approximately 12 months.

Sex

Female

Minimum age

18 Years

Maximum age

65 Years

Inclusion Criteria:

* GH deficiency due to pituitary or hypothalamic tumors or disease affecting this area. Subjects will have been treated with medication, surgery, radiation, or a combination of these. GH deficiency will be defined as a peak plasma GH of less than 5 ng/ml in response to insulin tolerance testing or growth hormone releasing hormone (GHRH) plus arginine stimulation test. In subjects with suspected hypothalamic dysfunction the arginine plus L-dopa stimulation test may be used, with a cutoff of 1.7 ng/ml for diagnosis of GH deficiency. Partial GH deficiency will be defined as a GH peak of 5 to 9 ng/ml (inclusive) during insulin tolerance testing or GHRH plus arginine testing.
* GH deficiency will also be diagnosed if insulin-like growth factor-I (IGF-I) levels are below 2 standard deviations for the age-sex normal range in a patient with at least two documented hormone deficiencies.
* Subjects must have evidence of a stable pituitary mass (for at least 12 months) if there is a history of a tumor except in the case of ACTH-producing microadenomas, where no follow-up imaging is required after cure.
* Subjects age 40 and over must have a screening mammogram if they have not already had one within one year prior to their baseline visit

Exclusion Criteria:

* Active Cushing's disease within 1 year
* History of acromegaly
* Untreated thyroid or adrenal insufficiency. Subjects on replacement therapy must be stable for at least 3 months prior to entry into the study.
* History of malignancy except for skin cancer and except for childhood solid malignancy with documented cure for \> 10 years prior to starting the study
* Hemoglobin \<10.0 gm/dl
* Hepatic or renal disease (SGPT/SGOT \> 3x upper limit of normal (ULN) or creatinine levels \>2.5 mg/dl)
* Congestive heart failure (CHF) (New York Heart Association's classification system Class II-IV CHF will be excluded)
* History of unstable cardiovascular disease (coronary artery or cerebrovascular disease) or symptoms within one year prior to entry into the study
* Diabetes mellitus
* Pregnancy or nursing
* Active carpal tunnel syndrome

• BACKGROUNDRosen T, Bengtsson BA. Premature mortality due to cardiovascular disease in hypopituitarism. Lancet. 1990 Aug 4;336(8710):285-8. doi: 10.1016/0140-6736(90)91812-o. PMID 1973979
• BACKGROUNDBulow B, Hagmar L, Eskilsson J, Erfurth EM. Hypopituitary females have a high incidence of cardiovascular morbidity and an increased prevalence of cardiovascular risk factors. J Clin Endocrinol Metab. 2000 Feb;85(2):574-84. doi: 10.1210/jcem.85.2.6346. PMID 10690858
• BACKGROUNDWuster C, Slenczka E, Ziegler R. [Increased prevalence of osteoporosis and arteriosclerosis in conventionally substituted anterior pituitary insufficiency: need for additional growth hormone substitution?]. Klin Wochenschr. 1991 Oct 18;69(16):769-73. doi: 10.1007/BF01797616. German. PMID 1762381
• BACKGROUNDTomlinson JW, Holden N, Hills RK, Wheatley K, Clayton RN, Bates AS, Sheppard MC, Stewart PM. Association between premature mortality and hypopituitarism. West Midlands Prospective Hypopituitary Study Group. Lancet. 2001 Feb 10;357(9254):425-31. doi: 10.1016/s0140-6736(00)04006-x. PMID 11273062
• BACKGROUNDMarkussis V, Beshyah SA, Fisher C, Sharp P, Nicolaides AN, Johnston DG. Detection of premature atherosclerosis by high-resolution ultrasonography in symptom-free hypopituitary adults. Lancet. 1992 Nov 14;340(8829):1188-92. doi: 10.1016/0140-6736(92)92892-j. PMID 1359261
• BACKGROUNDPfeifer M, Verhovec R, Zizek B, Prezelj J, Poredos P, Clayton RN. Growth hormone (GH) treatment reverses early atherosclerotic changes in GH-deficient adults. J Clin Endocrinol Metab. 1999 Feb;84(2):453-7. doi: 10.1210/jcem.84.2.5456. PMID 10022400
• BACKGROUNDEvans LM, Davies JS, Goodfellow J, Rees JA, Scanlon MF. Endothelial dysfunction in hypopituitary adults with growth hormone deficiency. Clin Endocrinol (Oxf). 1999 Apr;50(4):457-64. doi: 10.1046/j.1365-2265.1999.00671.x.