GH replacement in adults: interactions with other pituitary hormone deficiencies and replacement therapies

Abstract

Severe GH deficiency (GHD) in adults has been described as a clinical entity. However, some of the features associated with GHD could be due to unphysiological and inadequate replacement of other pituitary hormone deficiencies. This may be true for glucocorticoid replacement that lacks a biomarker making dose titration and monitoring difficult. Moreover, oral estrogen replacement therapy decreases IGF1 levels compared with the transdermal route, which attenuates the responsiveness to GH replacement therapy in women. In addition, in untreated female hypogonadism, oral estrogen may augment the features associated with GHD in adult women. Important interactions between the hormones used for replacing pituitary hormone deficiency occur. Introducing GH replacement may unmask both an incipient adrenal insufficiency and central hypothyroidism. Therefore, awareness and proper monitoring of these hormonal interactions are important in order to reach an optimal replacement therapy. This review will focus on the complex hormonal interactions between GH and other pituitary hormones in GHD and in GH replacement. European Journal of Endocrinology 161 S85-S95

Assessment of glucocorticoid therapy with salivary cortisol in secondary adrenal insufficiency

“…We considered the 2.5th and 97.5th percentiles of AUC 0-14 , AUC 0-7 , and AUC [7][8][9][10][11][12][13][14] in the healthy controls as the lower and upper limits of normality. Each patient's salivary cortisol levels are shown in Fig.…”

“…To take into account multiple comparisons, the raw P values in group comparisons for the salivary samples at fixed times and AUC obtained with Wilcoxon test were adjusted with Bonferroni's method. Linear regression analysis was used to examine the relationship between salivary cortisol F 1.5 and AUC 0-7 , and between F 8.5 and AUC [7][8][9][10][11][12][13][14] . The database was managed and statistical analysis performed by SAS 9.1 for Windows (SAS Institute, Inc., Cary, NC, USA) or Excel 2010 for Windows.…”

“…To assess endogenous daily cortisol secretion in healthy controls and glucocorticoid exposure in patients, we computed the area under the curve (AUC) for salivary cortisol levels at the different time points with respect to the ground (AUC 0-14 ), according to the trapezoidal formula proposed by Pruessner et al (30). We divided the day being examined into two different periods of 7 h, called AUC 0-7 (from F 0 to F 7) and AUC [7][8][9][10][11][12][13][14] (from F 7 to F 14).…”

“…Optimal replacement should produce cortisol concentrations that mirror the circadian cortisol rhythm (2), but available immediate-release glucocorticoid preparations only partially replicate the physiological cortisol profile (3); expertise with modified-release hydrocortisone (HC) tablets is still inadequate (4,5). Secondary AI coexists with other pituitary hormone deficiencies; their replacement therapies may interfere with glucocorticoid metabolism and action (6,7,8,9). A number of methods (urinary free cortisol, serum cortisol, or clinical score) have been suggested for assessing the adequacy of glucocorticoid replacement, but there is no consensus about the most reliable in clinical practice (1,3,10,11).…”

Growth Hormone & Hypopituitarism

“…Several studies have pointed that treatment continued throughout life is beneficial [1][2][3][4][5][6][7][8]. Moreover, elderly patients are more sensitive to Insulin-like growth factor-1 (IGF-1), so they require less dose of recombinant GH to achieve safer and effective level of IGF-1.…”