Myokines in Acromegaly: An Altered Irisin Profile.

Introduction: The muscle is an endocrine organ controlling metabolic homeostasis. Irisin and myostatin are key myokines mediating this process. Acromegaly is a chronic disease with a wide spectrum of complications, including metabolic disturbances. Purpose: To examine the influence of acromegaly on irisin and myostatin secretion and their contribution to metabolic profile and body composition. Materials and Methods: In 43 patients with acromegaly and 60 controls, serum levels of irisin, myostatin, growth hormone (GH), insulin-like growth factor 1 (IGF-1), parameters of glucose, and lipid metabolism were determined. Body composition was assessed with dual-energy x-ray absorptiometry. Results: The irisin concentration was significantly lower in patients with acromegaly compared to controls (3.91 vs. 5.09 µg/ml, p = 0.006). There were no correlations between irisin and GH/IGF-1 levels. In the study group, irisin was negatively correlated with fasting insulin (r = -0.367; p = 0.042), HOMA-IR (r = -0.510; p = 0.011), and atherogenic factors: Castelli I (r = -0.416; p = 0.005), Castelli II (r = -0.400; p = 0.001), and atherogenic coefficient (AC) (r = -0.417; p = 0.05). Irisin and myostatin concentrations were also lower in acromegalics with insulin resistance than without (2.80 vs. 4.18 µg/ml, p = 0.047; 81.46 vs. 429.58 ng/L, p = 0.018, respectively). There were no differences between study group and controls in myostatin concentration. Myostatin levels negatively correlated with GH (r = -0.306; p = 0.049), HOMA-IR (r = -0.046; p = 0.411), and insulin levels (r = -0.429; p = 0.016). Conclusions: Decreased irisin concentrations in acromegaly may suggest impaired hormonal muscle function contributing to metabolic complications in this disorder. However, learning more about the association between myostatin and GH in acromegaly requires further studies. Nevertheless, it appears that myostatin is not critical for muscle mass regulation in acromegaly.

The real costs of acromegaly: analysis of different therapies.

Acromegaly is a rare, chronic condition caused by growth hormone (GH) overproduction, usually due to a benign tumour of the pituitary gland. During the disease many complications occur, including cardiovascular disease and changes in the musculoskeletal, respiratory, and endocrine systems. Treatment includes surgery, medical therapy, and radiation. In this paper a literature review was conducted for information related to costs of management of acromegaly and its associated comorbidities using PubMed.The majority of total costs represent pharmacological treatment, especially the most common somatostatin analogues (SSA) therapy. The average reported annual cost of SSA therapy is EUR 12,000-40,000. Surgery reduces the cost of care via the possibility of avoiding lifelong pharmacological treatment. Radiotherapy is also suggested to lower the costs of therapy because about 60% of patients eventually will not require further pharmacological treatment; however, it is connected with negative outcomes like hypopituitarism, lower quality of life, and increased mortality. Cabergoline and pegvisomant are the lowest and highest priced treatments, respectively, but the overall impact on the cost of therapy is minor due to less frequent usage of these drugs. It is hard to fully estimate the impact of comorbidities of acromegaly on financial burden because patients are treated for them many years before the diagnosis of the underlying pathology. The treatment cost of comorbidities is higher in uncontrolled patients. Life-long treatment of acromegaly and its comorbidities is very expensive. Early diagnosis and successful treatment reduce direct and indirect costs.