Acromegaly is characterized by growth hormone (GH) and insulin-like growth factor 1 (IGF1) excess and is accompanied by an increased cardiovascular diseases (CVD) risk. As innate immune responses are crucial in CVD development, and IGF1 is linked to subclinical inflammation, we hypothesized that GH/IGF1 excess contributes to CVD development by potentiating systemic inflammation. We aimed to assess the effects of GH/IGF1 on inflammatory cytokine production. Whole blood from acromegaly patients and healthy volunteers and peripheral blood mononuclear cells (PBMCs) from healthy volunteers were stimulated with Toll-like receptor (TLR) ligands, with or without adding GH or IGF1 (in PBMC). Cytokine concentrations were measured by ELISA. The underlying signalling pathways were investigated by the inhibition of downstream targets of the IGF1 receptor. The following results were obtained. GH or IGF1 alone did not influence cytokine production in PBMCs. GH did not affect TLR-induced cytokine production, but co-stimulation with IGF1 dose dependently increased the TLR ligand-induced production of IL6 ( < 0.01), TNF alpha ( = 0.02) and IFNg ( < 0.01), as well as the production of the anti-inflammatory cytokine IL10 ( = 0.01). IGF1 had no effect on IL1B, IL17 and IL22 production. Inhibition of the MAPK pathway, but not mTOR, completely abrogated the synergistic effect of IGF1 on the LPS-induced IL6 and TNF alpha production. In whole blood of acromegaly patients, IL6 production was increased ( < 0.01). In conclusion, IGF1, but not GH, has pro-inflammatory effects, probably via the MAPK signalling pathway and might be involved in the pathogenesis of atherosclerosis in acromegaly. The increased IL10 production possibly counteracts the pro-inflammatory effects.

Acromegaly is characterized by Growth Hormone (GH) and Insulin-like Growth Factor 1 (IGF-1) excess. Uncontrolled acromegaly is associated with a strongly increased risk of cardiovascular disease (CVD), and numerous cardiovascular risk factors remain present after remission. GH and IGF-1 have numerous effects on the immune and cardiovascular system. Since endothelial damage and systemic inflammation are strongly linked to the development of CVD, and have been suggested to be present in both controlled as uncontrolled acromegaly, they may explain the presence of both micro- and macrovascular dysfunction in these patients. In addition, these changes seem to be only partially reversible after remission, as illustrated by the often reported presence of endothelial dysfunction and microvascular damage in controlled acromegaly. Previous studies suggest that insulin resistance, oxidative stress, and endothelial dysfunction are involved in the development of CVD in acromegaly. Not surprisingly, these processes are associated with systemic inflammation and respond to GH/IGF-1 normalizing treatment.

Context Transsphenoidal surgery (TSS) is the primary treatment of choice in acromegaly. It is important to identify patients in whom surgical cure is not attainable at an early stage, both to inform patients on expected treatment outcome and to select those who are more likely to need additional therapy. Objective To identify predictors for remission after TSS in acromegaly. Design Large multicenter study with retrospective data collection from three tertiary neurosurgical referral centers in the Netherlands. Methods We analyzed clinical data since 2000 from three cohorts (Groningen, Nijmegen and Rotterdam, total n=282). Multivariate regression models were used to identify predictors of early biochemical remission (12 weeks-1 year postoperatively) according to the 2010 consensus criteria, long-term remission (age- and sex normalized IGF-1 and the absence of postoperative treatment until last follow-up) and relative IGF-1 and GH reduction. Results A larger maximum tumor diameter (OR 0.91, 95% CI 0.87–0.96, p≤0.0001) was associated with a lower chance of early biochemical remission. A larger maximum tumor diameter (OR 0.93, 95% CI 0.89–0.97, p=0.0022) and a higher random GH concentration at diagnosis (OR 0.98, 95% CI 0.96–0.99, p=0.0053) were associated with a lower chance of long-term remission. Conclusion Maximum tumor diameter and random GH concentration at diagnosis are the best predictors for remission after TSS in acromegaly.

Background Obstructive sleep apnea syndrome (OSAS) is common in active acromegaly and negatively influences quality of life, morbidity, and mortality. This prospective study with 3 predetermined timepoints and a standardized treatment protocol investigates changes in sleep parameters during the first 2.5 years of acromegaly treatment. Methods Before initiation of acromegaly treatment (medical pretreatment followed by surgery), polysomnography (PSG) was performed in 27 consecutive patients with treatment-naive acromegaly. PSG was repeated after 1 year (N = 24) and 2.5 years (N = 23), and anthropometric and biochemical parameters were obtained. Results At baseline, 74.1% of the patients was diagnosed with OSAS. The respiratory disturbance index (RDI; P = 0.001), oxygen desaturation index (ODI; P = 0.001), lowest oxygen saturation (LSaO2; P = 0.007) and the Epworth Sleepiness Scale (ESS; P &lt; 0.001) improved significantly during treatment, with the greatest improvement in the first year. After 2.5 years of treatment, all patients had controlled acromegaly. Of the 16 patients with repeated PSG and OSAS at baseline, 11 (68.8%) were cured of OSAS. Changes in RDI, ODI, LSaO2, and ESS correlated with insulin-like growth factor 1 levels. Conclusion OSAS has a high prevalence in active acromegaly. There is a substantial decrease in prevalence and severity of OSAS following acromegaly treatment, with the largest improvement during the first year. Most patients recover from OSAS following surgical or biochemical control of the acromegaly. Therefore, a PSG is advised after diagnosis of acromegaly. When OSAS is present, it should be treated and PSG should be repeated during acromegaly treatment.