The changing landscape of acromegaly - an epidemiological perspective.

Acromegaly is a rare disease and thus challenging to accurately quantify epidemiologically. In this comprehensive literature review, we compare different approaches to studying acromegaly from an epidemiological perspective and describe the temporal evolution of the disease pertaining to epidemiological variables, clinical presentation and mortality. We present updated epidemiological data from the population-based Danish cohort of patients with acromegaly (AcroDEN), along with meta-analyses of existing estimates from around the world.Based on this, we conclude that the incidence, prevalence and age at acromegaly diagnosis are all steadily increasing, but with considerable variation between studies. An increased number of incidental cases may contribute to the increase in incidence and age at diagnosis, respectively. The clinical features at presentation are trending toward a milder disease phenotype at diagnosis, and advances in therapeutic options have reduced the mortality of patients with acromegaly to a level similar to that of the general population. Moreover, the underlying cause of death has shifted from cardiovascular to malignant neoplastic diseases.

Changes in acromegaly comorbidities, treatment, and outcome over three decades: a nationwide cohort study.

Objective: To study the time-dependent changes in disease features of Danish patients with acromegaly, including treatment modalities, biochemical outcome, and comorbidities, with a particular focus on cancer and mortality. Methods: Pertinent acromegaly-related variables were collected from 739 patients diagnosed since 1990. Data are presented across three decades (1990-1999, 2000-2009, and 2010-2021) based on the year of diagnosis or treatment initiation. Results: Adenoma size and insulin-like growth factor I (IGF-I) levels at diagnosis did not differ significantly between study periods. The risk of being diagnosed with diabetes, heart disease, sleep apnea, joint disease, and osteoporosis increased from the 1990s to the later decades, while the mortality risk declined to nearly half. The risk of cancer did not significantly change. Treatment changed toward the use of more medical therapy, and fewer patients underwent repeat surgeries or pituitary irradiation. A statistically significant increase in the proportion of patients achieving IGF-I normalization within 3-5 years was observed over time (69%, 83%, and 88%). The proportion of patients with three or more deficient pituitary hormones decreased significantly over time. Conclusion: Modern medical treatment regimens of acromegaly as well as increased awareness and improved diagnostics for its comorbidities have led to better disease control, fewer patients with severe hypopituitarism, and declining mortality in the Danish cohort of acromegaly patients. The risk of cancer did not increase over the study period.

Gene expression profiling of subcutaneous adipose tissue reveals new biomarkers in acromegaly.

CONTEXT: Active acromegaly is characterized by lipolysis-induced insulin resistance, which suggests adipose tissue (AT) as a primary driver of metabolic aberrations. OBJECTIVE: To study the gene expression landscape in AT in patients with acromegaly before and after disease control in order to understand the changes and to identify disease-specific biomarkers. METHODS: RNA sequencing was performed on paired subcutaneous adipose tissue (SAT) biopsies from six patients with acromegaly at time of diagnosis and after curative surgery. Clustering and pathway analyses were performed in order to identify disease activity-dependent genes. In a larger patient cohort (n = 23), the corresponding proteins were measured in serum by immunoassay. Correlations between growth hormone (GH), insulin-like growth factor I (IGF-I), visceral AT (VAT), SAT, total AT, and serum proteins were analyzed. RESULTS: 743 genes were significantly differentially expressed (P-adjusted < .05) in SAT before and after disease control. The patients clustered according to disease activity. Pathways related to inflammation, cell adhesion and extracellular matrix, GH and insulin signaling, and fatty acid oxidation were differentially expressed.Serum levels of HTRA1, METRNL, S100A8/A9, and PDGFD significantly increased after disease control (P < .05). VAT correlated with HTRA1 (R = 0.73) and S100A8/A9 (R = 0.55) (P < .05 for both). CONCLUSION: AT in active acromegaly is associated with a gene expression profile of fibrosis and inflammation, which may corroborate the hyper-metabolic state and provide a means for identifying novel biomarkers.

Growth Hormone and Obesity.

Growth hormone (GH) exerts IGF-I dependent protein anabolic and direct lipolytic effects. Obesity reversibly suppresses GH secretion driven by elevated FFA levels, whereas serum IGF-I levels remain normal or elevated due to elevated portal insulin levels. Fasting in lean individuals suppresses hepatic IGF-I production and increases pituitary GH release, but this pattern is less pronounced in obesity. Fasting in obesity is associated with increased sensitivity to the insulin-antagonistic effects of GH. GH treatment in obesity induces a moderate reduction in fat mass and an increase in lean body mass but the therapeutic potential is uncertain.

Temporal patterns of lipolytic regulators in adipose tissue after acute growth hormone exposure in human subjects: A randomized controlled crossover trial.

OBJECTIVE: Growth hormone (GH) stimulates lipolysis, but the underlying mechanisms remain incompletely understood. We examined the effect of GH on the expression of lipolytic regulators in adipose tissue (AT). METHODS: In a randomized, placebo-controlled, cross-over study, nine men were examined after injection of 1) a GH bolus and 2) a GH-receptor antagonist (pegvisomant) followed by four AT biopsies. In a second study, eight men were examined in a 2 × 2 factorial design including GH infusion and 36-h fasting with AT biopsies obtained during a basal period and a hyperinsulinemic-euglycemic clamp. Expression of GH-signaling intermediates and lipolytic regulators were studied by PCR and western blotting. In addition, mechanistic experiments in mouse models and 3T3-L1 adipocytes were performed. RESULTS: The GH bolus increased circulating free fatty acids (p < 0.0001) together with phosphorylation of signal transducer and activator of transcription 5 (STAT5) (p < 0.0001) and mRNA expression of the STAT5-dependent genes cytokine-inducible SH2-containing protein (CISH) and IGF-1 in AT. This was accompanied by suppressed mRNA expression of G0/G1 switch gene 2 (G0S2) (p = 0.007) and fat specific protein 27 (FSP27) (p = 0.002) and upregulation of phosphatase and tensin homolog (PTEN) mRNA expression (p = 0.03). Suppression of G0S2 was also observed in humans after GH infusion and fasting, as well as in GH transgene mice, and in vitro studies suggested MEK-PPARγ signaling to be involved. CONCLUSIONS: GH-induced lipolysis in human subjects in vivo is linked to downregulation of G0S2 and FSP27 and upregulation of PTEN in AT. Mechanistically, in vitro data suggest that GH acts via MEK to suppress PPARγ-dependent transcription of G0S2. ClinicalTrials.govNCT02782221 and NCT01209429.

[Acromegaly].

Acromegaly is a rare and disabling disease with a plethora of symptoms and signs attributed to sustained elevations and actions of growth hormone and insulin-like growth factor 1. Acromegaly is characterised by excessive somatic growth and multiple comorbidities in addition to occasional compression of the optic nerve and hypopituitarism due to the underlying adenoma. The course of the disease is insidious, and a diagnostic delay of 5-10 years is typical, and this pre-diagnostic period is also associated with increased morbidity. Effective treatment is available, once the diagnosis is established.

[Acromegaly and symptoms of the motor apparatus].

In this case report, a 72-year-old woman presented with symptoms attributed to arthritis, and MRI indicated sacroiliitis. However, the patient also experienced enlargement of hands and feet in addition to sweating and snoring, which in combination with coarse facial features suggested acromegaly. This diagnosis was biochemically confirmed, and MRI revealed a pituitary adenoma, which was successfully removed by transsphenoidal surgery. Symptom relief and reduced swelling occurred immediately post-operatively. Acromegaly can masquerade as arthritis or osteoarthritis, which may delay diagnosis.