ASSESSMENT OF DIASTOLIC DYSFUNCTION, ARTERIAL STIFFNESS, AND CAROTID INTIMA-MEDIA THICKNESS IN PATIENTS WITH ACROMEGALY

Distinct clinical characteristics and prognosis of pediatric-onset growth hormone-secreting pituitary adenoma (GHPA) patients compared to adult-onset patients

PURPOSE

To explore the clinical characteristics, treatment, and prognosis of growth hormone-secreting pituitary adenoma (GHPA) patients with pediatric-onset, so as to facilitate clinical management.

METHODS

A retrospective cohort study was carried out between 102 pediatric-onset GHPA patients admitted to our hospital from January 2013 to June 2022 and 204 adult-onset GHPA patients who were randomly matched.

RESULTS

GHPA with pediatric-onset was predominantly male, associated with higher proportion of genetic syndromes, longer course, and delayed diagnosis. Clinical symptoms of visual field defects and menstrual abnormality were more common. The pediatric-onset group exhibited higher growth hormone (GH) nadir during oral glucose tolerance test (OGTT), higher rates of hyperprolactinemia, larger maximum diameter of adenoma, and higher rates of optic chiasm compression, suprasellar invasion, and pituitary apoplexy. Hypertension, diabetes, and obstructive sleep apnea-hypopnea syndrome (OSAHS) were more common in the adult-onset group. Echocardiography results were similar between the two groups. The pediatric-onset group owned significantly higher treatment scores and proportions of multimodal therapy modality, more surgical complications, and a higher proportion of ki67 ≥ 3%. There was no significant difference in the final cure rate, but male patients with adult-onset had a worse prognosis. The recurrence rate was also similar between two groups. Hypopituitarism was more prevalent in the pediatric-onset group, while the adult-onset group had a higher incidence of other tumors.

CONCLUSION

Pediatric-onset GHPA patients exhibit distinct clinical characteristics compared to adult-onset patients. Multimodal therapy modalities could help to achieve a cure rate comparable to that of adult-onset patients.

Cardiovascular Disorders Associated With Acromegaly: an Update

The most common causes of increased cardiovascular mortality in acromegaly are cardiac arrhythmias and sudden cardiac death. Acromegalic cardiomyopathy is defined as concentric biventricular hypertrophy and diastolic dysfunction when other cardiac diseases such as hypertension, diabetes mellitus, and arrhythmias-related cardiac disorders have been excluded. This also contributes to significant morbidity and mortality in these patients. The main risk factors contributing to the development of cardiomyopathy include advancing age, disease duration, and body mass index. The duration of growth hormone excess is more closely associated with the development of biventricular enlargement, diastolic dysfunction, heart failure, and valvular disease than the degree of hormone elevation. Additionally, other cardiovascular disorders such as coronary artery disease, arrhythmias, valvular heart diseases, systemic hypertension, atherosclerosis, and rarely congestive cardiac failure are involved in the shortened life span of these patients especially if poorly controlled. Biochemical control of acromegaly with the recently available multimodal treatment along with better management of cardiovascular comorbidities has improved the morbidity and mortality rates of patients with acromegaly. However, with the recent advances in the treatment of acromegaly, neoplastic causes presently remain as the main leading cause of death in these patients.

IGF-1 levels in the general population, heart failure patients, and individuals with acromegaly: differences and projections from meta-analyses-a dual perspective

Background

The complex relationship between insulin-like growth factor 1 (IGF-1) levels and heart failure (HF) is not fully understood, particularly across different populations and conditions. This meta-analysis aims to elucidate the dual perspectives of IGF-1 levels in the general population, HF patients, and individuals with treatment-naïve acromegaly, highlighting IGF-1 as a biomarker and potential therapeutic target in HF management.

Methods

Studies were searched across multiple electronic databases up to January 2024 and independently identified by reviewers. The outcomes were analyzed using RevMan 5.4 and STATA 15.

Results

A total of 25 articles were ultimately included in the analysis. Six studies compared IGF-1 levels between HF patients and non-HF controls, revealing significantly lower IGF-1 levels in HF patients (mean difference -20.93; 95% CI -37.88 to -3.97; p = 0.02). This reduction was consistent across various HF subtypes and severities. In addition, individuals with intermediate IGF-1 levels had a lower risk of developing HF [risk ratio (RR) 0.78; 95% CI 0.74-0.83; p < 0.01] and HF-related mortality (RR 0.98; 95% CI 0.97, 0.99; p < 0.01) compared to those with low IGF-1 levels, suggesting a protective role for maintaining adequate IGF-1 levels. Conversely, treatment-naïve acromegaly patients, characterized by excessively high IGF-1 levels, showed a significantly higher incidence of both diastolic HF [odds ratio (OR) 9.08; 95% CI 6.20-13.29; p < 0.01] and systolic HF (OR 13.1; 95% CI 6.64-25.84; p < 0.01), implicating supraphysiological IGF-1 levels in adverse cardiac outcomes.

Conclusions

Our meta-analysis highlights the complex interplay between IGF-1 levels and HF. We found that reduced IGF-1 levels are commonly observed in HF patients and are associated with an increased risk of HF and higher HF-related mortality. Conversely, excessively high levels, as observed in acromegaly, are linked to a higher incidence of HF. Based on these results, it is recommended that cardiac function be closely monitored in patients with reduced IGF-1 levels and in those with acromegaly. These findings suggest that IGF-1 could hold potential prognostic value for risk stratification in HF.

An Overview of Cardiovascular Risk in Pituitary Disorders

Cardiovascular comorbidities owing to hormonal excess or deficiency are the main cause of mortality in patients with pituitary disorders. In patients with Cushing's Disease, there is an increased prevalence of cardiovascular diseases and/or risk factors including visceral obesity, insulin resistance, atherosclerosis, arterial hypertension, dyslipidaemia, hypercoagulability as well as structural and functional changes in the heart, like cardiac hypertrophy and left ventricle (LV) dysfunction. Notably, these demonstrate limited reversibility even after remission. Furthermore, patients with acromegaly may manifest insulin resistance but also structural and functional heart changes, also known as "acromegalic cardiomyopathy". Patients with prolactinomas demonstrate an aggravation of metabolic parameters, obesity, dysregulation of glucose and lipid metabolism as well as endothelial dysfunction. Hypopituitarism and conventional hormonal replacement therapy may also contribute to an unhealthy metabolic status, which promotes atherosclerosis and may lead to premature mortality. This review discusses the literature on cardiovascular risk in patients with pituitary disorders to increase physician awareness regarding this aspect of management in patients with pituitary disorders.

Myocardial, Valvular, and Vascular Structural and Functional Properties in Acromegaly

Acromegaly is an uncommon systematic endocrine disease caused by the hypersecretion of human growth hormone and, consequently, of insulin-like growth factor-1 during adulthood. Acromegaly could cause a typical cardiomyopathy characterized by left ventricular hypertrophy associated with diastolic dysfunction, which later could progress to systolic dysfunction. Moreover, some valvular and vascular abnormalities are also associated with acromegaly. This present review aims to summarize available information regarding acromegaly-associated abnormalities in myocardial, valvular, and vascular structural and functional properties and their relationship to disease activity and treatment options.

Filling the gap between the heart and the body in acromegaly: a case-control study

OBJECTIVE

Cardiovascul diseases are the most common comorbidities in acromegaly. Potential parameters in pathology of cardiovascular comorbidities are changes in levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) as well as body composition parameters.

PURPOSE

The aim of this study was to examine morphological and functional parameters of the cardiovascular system by echocardiography and to assess its relationship with disease activity and body composition parameters.

METHODS

We prospectively enroled 129 acromegalic patients (82 females, 47 males) and 80 healthy controls (53 females, 27 males) matched for age, gender, and BMI. All patients underwent two-dimensional echocardiography. Body composition parameters were assessed by dual-energy X-ray absorptiometry.

RESULTS

Acromegaly patients presented with higher left ventricle mass (LVM) compared to controls (LVMI: 123 ± 45 g/m² vs 83 ± 16 g/m², P < 0.001). Prevalence of left ventricle hypertrophy in acromegaly patients was 67% (78% concentric, 22% eccentric). IGF -1 levels, BMI, and lean mass positively correlated with LVM in all acromegaly patients (P < 0.001). Fat mass positively correlated with LVM in females (R = 0.306, P = 0.005), but this correlation was not found in males. We did not find any difference in size of the left and right ventricle between acromegaly patients and controls. Acromegaly patients presented with left atrium enlargement, diastolic dysfunction and low incidence of systolic dysfunction. Valvopathy was found in 43% of patients with predominant (31%) prevalence of mitral regurgitation.

CONCLUSION

Our study demonstrates higher prevalence of cardiovascular comorbidities in acromegaly patients and the impact of IGF-1 levels and body composition parameters in pathology in some of these comorbidities.

Vascular anomalies in patients with growth hormone-secreting pituitary adenomas: illustrative case report and systematic review of the literature

PURPOSE

Endonasal resection is the first-line treatment for patients harboring growth hormone (GH)-secreting pituitary adenomas. The complexity of the parasellar neurovascular structures makes pre-operative diagnostic imaging essential to understanding the anatomy of this region. We aimed to describe vascular anomalies in acromegalic patients and emphasize their relevance for surgery and preoperative planning.

METHODS

A systematic review following the PRISMA statement was performed in July 2021.

RESULTS

Thirty-three studies were evaluated. Elevated GH and insulin-like growth factor-1 (IGF-1) levels are linked to the occurrence of cardiovascular risk factors. This is attributed to endothelial dysfunction, mainly caused by changes in flow-mediated dilatation (FMD), which is probably the main cause of vascular anomalies in acromegaly. The occurrence of protrusions of the internal carotid artery (ICA) (35-53%), a narrow intercarotid distance, and an asymmetrical course was described. In 13-18% of acromegalic patients, the presence of an intracerebral aneurysm could be reported (incidence in the general population:0.8-1.3%). The selected studies were however performed with a small patient sample (range:1-257). We present a case report of a 57y/o male patient with anomalies of the ICA ("kissing carotid arteries") harboring a GH-secreting adenoma, which was resected via an endoscopic endonasal approach.

CONCLUSIONS

There is an association between acromegaly and endothelial dysfunction, which increases cardiovascular risk factors and vascular anomalies. Preoperative vascular imaging, e.g., CT angiography, should be implemented as a standard to identify patients at risk and estimate surgical morbidity. However, no evidence-based recommendations exist so far, so future studies are necessary.

Capillary microarchitectural changes are independent of disease activity in acromegaly

OBJECTIVE

Although atherosclerosis-related macrovascular complications are well known in acromegaly, studies on endothelial function and arteriolar level are contradictory. In order to test the hypothesis, microvascular changes associated with macrovascular changes in acromegaly, we aimed to evaluate microvascular changes in nailfold capillaries and carotid intima-media thickness (CIMT) in patients with acromegaly.

DESIGN

In this cross-sectional observation study, of total 70 patients with acromegaly [ten (14.3 %) were active acromegaly (AA), 60 (85.7 %) were controlled acromegaly (CA)] and 74 healthy controls were enrolled. Microvascular structure was evaluated using the nailfold video capillaroscopy, and CIMT was measured using ultrasonography.

RESULTS

The median number of capillaries was less [10 no./mm (min-max: 5-16) vs. 11 no./mm (min-max: 9-15); p = 0.001] in the acromegaly group than in the controls. Capillaries below 6-8 per/mm was more common in the acromegaly patients [six (8.6 %) vs. one (1.4 %); p = 0.046]. All capillaroscopic parameters were similar among the patients with CA or AA. CIMT levels were higher in the acromegaly group than in the control group [0.60 mm (0.43-0.86) vs. 0.38 mm (0.27-0.59); p < 0.001], and AA patients had higher CIMT than CA patients (p = 0.037). None of the clinical or laboratory parameters including growth hormone and IGF-1 were related to capillaroscopic parameters or CIMT.

CONCLUSION

Decreased capillary number was the major capillaroscopic finding in acromegaly and there was no significant difference between active and controlled cases, but CIMT was found to be higher in the active group. Increased CIMT levels in acromegaly were not associated with capillary changes. Large-scale, prospective studies are needed to make a definite conclusion about the effect of the disease activity on nailfold capillaries and its association with macrovascular changes.

Emerging Roles of miRNA, lncRNA, circRNA, and Their Cross-Talk in Pituitary Adenoma

Pituitary adenoma (PA) is a common intracranial tumor without specific biomarkers for diagnosis and treatment. Non-coding RNAs (ncRNAs), including microRNAs (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA), regulate a variety of cellular processes, such as cell proliferation, differentiation, and apoptosis. Increasing studies have shown that the dysregulation of ncRNAs, especially the cross-talk between lncRNA/circRNA and miRNA, is related to the pathogenesis, diagnosis, and prognosis of PA. Therefore, ncRNAs can be considered as promising biomarkers for PA. In this review, we summarize the roles of ncRNAs from different specimens (i.e., tissues, biofluids, cells, and exosomes) in multiple subtypes of PA and highlight important advances in understanding the contribution of the cross-talk between ncRNAs (e.g., competing endogenous RNAs) to PA disease.

"Subclinical atherosclerosis in acromegaly: Possible association with cardiovascular risk factors rather than disease activity"

OBJECTIVE

Cardiovascular (CV) disease is still a major cause of excessive morbidity and mortality in patients with active acromegaly, which may be attributed to a high prevalence of associated pro-atherosclerotic risk factors. However, a direct effect of GH/IGF-1 excess on the vasculature has been previously suggested, warranting further investigation. The present study was designed to investigate whether chronic GH/IGF-1 excess is associated with an increased prevalence of subclinical atherosclerosis in patients with acromegaly.

DESIGN

We measured carotid intima-media thickness (cIMT) and assessed carotid plaques by ultrasonography along with classical CV risk factors in 54 acromegaly patients (34 females, 50 ± 12 years and compared those with 62 (42 females, 53 ± 13 years) age-, sex- and CV risk factors- matched controls. In order to compare cIMT measurements between patients and controls we analyzed common carotid artery far wall data as well as a combined measurement result, which consisted of the mean value of the six different measurements, three at each side.

RESULTS

mean ± SD serum GH and IGF-1 levels were 2.76 ± 4.65 ng/mL and 1.7 ± 1.25 x ULN, respectively, in all acromegaly patients. Age, body mass index, blood pressure, lipid levels, fasting glucose and Framingham's global cardiovascular risk score classification were similar comparing patients and controls. Combined median [IQR] cIMT measurements were similar in acromegaly patients and matched controls (0.59 [0.52-0.66] mm vs. 0.59 [0.52-0.69] mm; P = 0.872) as well as in acromegaly patients with active and controlled disease (0.59 [0.51-0.68] mm vs. 0.60 [0.54-0.68] mm; P = 0.385). No significant correlations were observed between cIMT measurements and GH (Spearman r = 0.1, P = 0.49) or IGF-1 (Spearman r = 0.13, P = 0.37) levels in patients with acromegaly. Carotid atherosclerotic plaques prevalence was similar in patients and controls (26% vs. 32%; P = 0.54) as well as in patients with active and controlled acromegaly (22% vs. 30%; P = 0.537).

CONCLUSIONS

Our data suggest that GH/IGF-1 excess itself is not one of the main drivers of subclinical morphological atherosclerosis changes in patients with acromegaly and that optimal control of acromegaly-associated CV risk factors may preserve vasculature structure even when strict biochemical control is not achieved.

Arterial stiffness, carotid intima-media thickness, endocan and A disintegrin-like and metalloprotease with thrombospondin type I motif 9 levels and their relationship with disease activity in acromegaly patients with and without cardiovascular risk factors

OBJECTIVE

Cardiovascular complications such as cardiomyopathy and endothelial dysfunction, which are frequently seen in patients with acromegaly, are among the most important causes of morbidity and mortality. In this study, we aimed to investigate arterial stiffness, carotid intima-media thickness, endocan and A disintegrin-like and metalloprotease with thrombospondin type I motif 9 (ADAMTS9) levels and their relationship with disease activity in acromegaly patients with and without cardiovascular risk factors.

DESIGN

A total of 60 patients with acromegaly, 25 with active disease, 26 with well-controlled disease, and 9 newly diagnosed, and 60 age-, sex- and body mass index (BMI)-matched healthy control subjects were enrolled in this study. All subjects' height, weight, BMI, systolic blood pressure (SBP), distolic blood pressure (DBP), fasting plasma glucose (FPG), insulin, hemoglobin A1c (HbA1c), C-reactive protein (CRP), lipid, endocan, ADAMTS9, pulse wave velocity (PWV) and carotid intima-media thickness (CIMT) measurements were performed.

RESULTS

SBP, DBP, FPG, HbA1c and PWV levels of the acromegaly group were higher than the control group. In acromegaly patients with cardiovascular disease (CVD) risk factors, PWV was higher than the control group, and in acromegaly patients without CVD risk factor, PWV was similar to the control group. In the correlation analysis, a positive correlation was found between PWV and age, BMI, SBP, DBP, FPG and HbA1c levels in the acromegaly group.

CONCLUSIONS

In our study, we found that arterial stiffness increased in acromegaly patients with CVD risk factors, and that increased arterial stiffness was associated with hemodynamic (SBP, DBP) and metabolic (BMI, FPG, HBA1C) parameters.

Advances in Research on the Cardiovascular Complications of Acromegaly

Cardiovascular-related complications are one of the most common complications in patients with acromegaly, and can lead to an increased risk of death. Hypertension and cardiomyopathy are the main cardiovascular complications. The characteristics of acromegalic cardiomyopathy are concentric biventricular hypertrophy and diastolic dysfunction. In addition, arrhythmia and heart valve disease are common cardiac complications in acromegaly. Although the underlying pathophysiology has not been fully elucidated, the spontaneous overproduction of GH and IGF-1, increasing age, prolonged duration of disease and the coexistence of other cardiovascular risk factors are crucial to cardiac complications in patients with acromegaly. Early diagnosis and appropriate treatment of acromegaly might be beneficial for the prevention of cardiomyopathy and premature death.

Relationship between prenatal and postnatal conditions and accelerated postnatal growth. Impact on the rigidity of the arterial wall and obesity in childhood

Restricted growth in utero and accelerated postnatal growth (APG) in the postnatal period have been associated with the development of overweight, obesity and an increased cardiovascular risk in childhood. The objectives of this study were to evaluate the influence of prenatal and perinatal conditions on APG and to evaluate the influence of this APG on different cardiovascular risk factors such as body mass index (BMI), body fat mass index (FMI), blood pressure (BP) and arterial wall stiffness [carotid to femoral pulse wave velocity (cf-PWV)]. All measurements were performed in 355 children (185 boys and 170 girls; 8-11 years). Data on mother weight before and during pregnancy, gestational age (weeks), birth weight (g) and breastfeeding of children were obtained through interviews with families. Children who presented APG were born of mothers with lower BMIs before pregnancy and who gained less weight during the second trimester of pregnancy. They also have a lower gestational age and birth weight, a shorter duration of breastfeeding and a longer duration of artificial feeding (AF). Later in childhood, they had higher values of cf-PWV, BMI, FMI and higher prevalence of hypertension. Low maternal gestational weight gain, inadequate fetal development (low birth weight, shorter gestational age) and reduced breastfeeding duration favor APG. Infants with such APG had higher values of cf-PWV, BP, BMI and FMI later in childhood, along with a higher risk of hypertension and obesity. The interaction between APG and a longer duration of AF had a negative effect on cf-PWV (arterial stiffness) and FMI.

Exosomal hsa-miR-21-5p derived from growth hormone-secreting pituitary adenoma promotes abnormal bone formation in acromegaly

Growth hormone-secreting pituitary adenoma (GHPA), a benign endocrine tumor located in the base of the skull, results in acromegaly. In addition to the mass effect of the tumor itself in the sellar region, GHPA can lead to the overgrowth of almost every organ. Previous findings indicated that the processes underlying acromegaly were partly attributable to hyperactivity of the growth hormone/insulin-like growth factor-1 (GH/IGF-1) axis. However, the mechanisms driving this syndrome remains largely unknown. Additionally, the roles of GHPA-derived exosomes, which contain functional microRNAs and proteins that manipulate target cell proliferation and differentiation in distal extremities, are also unknown. In this study, we demonstrated that GHPA exosomes promote bone formation in vitro and trabecula number in vivo. The mechanism of increased trabecula formation may be attributable to GHPA exosome-induced osteoblast proliferation via increased cell viability and DNA replication. We further discovered that exosomal hsa-miR-21-5p plays a distinct role from the GH/IGF-1 axis in these processes. Accordingly, the results of this study provide a novel mechanism whereby GHPA influences distal extremities and a new perspective for treating GHPA.

Persistent inflammation and endothelial dysfunction in patients with treated acromegaly

OBJECTIVE

Acromegaly is characterized by an excess of growth hormone (GH) and insulin-like growth factor 1 (IGF1). Cardiovascular disease (CVD) risk factors are common in acromegaly and often persist after treatment. Both acute and long-lasting pro-inflammatory effects have been attributed to IGF1. Therefore, we hypothesized that inflammation persists in treated acromegaly and may contribute to CVD risk.

METHODS

In this cross-sectional study, we assessed cardiovascular structure and function, and inflammatory parameters in treated acromegaly patients. Immune cell populations and inflammatory markers were assessed in peripheral blood from 71 treated acromegaly patients (with controlled or uncontrolled disease) and 41 matched controls. Whole blood (WB) was stimulated with Toll-like receptor ligands. In a subgroup of 21 controls and 33 patients with controlled disease, vascular ultrasound measurements were performed.

RESULTS

Leukocyte counts were lower in patients with controlled acromegaly compared to patients with uncontrolled acromegaly and controls. Circulating IL18 concentrations were lower in patients; concentrations of other inflammatory mediators were comparable with controls. In stimulated WB, cytokine production was skewed toward inflammation in patients, most pronounced in those with uncontrolled disease. Vascular measurements in controlled patients showed endothelial dysfunction as indicated by a lower flow-mediated dilatation/nitroglycerine-mediated dilatation ratio. Surprisingly, pulse wave analysis and pulse wave velocity, both markers of endothelial dysfunction, were lower in patients, whereas intima-media thickness did not differ.

CONCLUSIONS

Despite treatment, acromegaly patients display persistent inflammatory changes and endothelial dysfunction, which may contribute to CVD risk and development of CVD.

Effects of somatostatin analog treatment on cardiovascular parameters in patients with acromegaly: A systematic review

Background:

There is a belief that in patients with acromegaly, first-generation somatostatin analogs (SSAs) might improve cardiovascular (CV) structure and function. However, most published clinical trials involved only a few patients and their results are rather variable. We aimed to conduct a systematic review on available studies on the impact of these drugs on CV parameters.

Materials and Methods:

A literature search was conducted in MEDLINE (OVID), EMBase, Cochrane, and ISI Web of Science for citations published until April 30 2018 to identify studies on our objective that considered changes in CV parameters. For this search, we established a Boolean search strategy using keywords related to “acromegaly,” “Somatostatin analog,” and “cardiovascular diseases and parameters.” All study types except for case reports or conference abstracts were included. Twenty-four studies (n = 558) fulfilled the inclusion criteria and were selected for final analysis.

Results:

In 12 studies (n = 350), decrease in heart rate (HR) and in 4 studies (n = 128), decrease in blood pressure (BP) was significant. In 15 studies (n = 320), left ventricular mass index (LVMi) changes were significant. In 9 studies (n = 202), the early diastole to peak velocity flow in late diastole (E/A ratio) was evaluated, and in 5 of them (n = 141), the improvement was significant. Eighteen studies (n = 366) examined changes in left ventricular ejection fraction (LVEF), 5 of which (n = 171) reported that these changes were significant. Decrease of left ventricular end-diastolic diameter was reported in only 2 studies (n = 27).

Conclusion:

We found that first-generation SSAs have a beneficial effect on cardiac parameters such as HR and LVMi. For other parameters such as LVEF, BP, LV diameter, and E/A ratio, we were not able to draw a firm conclusion.

IGF-1 and cardiovascular disease

Atherosclerosis is an inflammatory arterial pathogenic condition, which leads to ischemic cardiovascular diseases, such as coronary artery disease and myocardial infarction, stroke, and peripheral arterial disease. Atherosclerosis is a multifactorial disorder and its pathophysiology is highly complex. Changes in expression of multiple genes coupled with environmental and lifestyle factors initiate cascades of adverse events involving multiple types of cells (e.g. vascular endothelial cells, smooth muscle cells, and macrophages). IGF-1 is a pleiotropic factor, which is found in the circulation (endocrine IGF-1) and is also produced locally in arteries (endothelial cells and smooth muscle cells). IGF-1 exerts a variety of effects on these cell types in the context of the pathogenesis of atherosclerosis. In fact, there is an increasing body of evidence suggesting that IGF-1 has beneficial effects on the biology of atherosclerosis. This review will discuss recent findings relating to clinical investigations on the relation between IGF-1 and cardiovascular disease and basic research using animal models of atherosclerosis that have elucidated some of the mechanisms underlying atheroprotective effects of IGF-1.

Systemic Complications of Acromegaly and the Impact of the Current Treatment Landscape: An Update

Acromegaly is a chronic systemic disease with many complications and is associated with increased mortality when not adequately treated. Substantial advances in acromegaly treatment, as well as in the treatment of many of its complications, mainly diabetes mellitus, heart failure, and arterial hypertension, were achieved in the last decades. These developments allowed change in both prevalence and severity of some acromegaly complications and furthermore resulted in a reduction of mortality. Currently, mortality seems to be similar to the general population in adequately treated patients with acromegaly. In this review, we update the knowledge in complications of acromegaly and detail the effects of different acromegaly treatment options on these complications. Incidence of mortality, its correlation with GH (cumulative exposure vs last value), and IGF-I levels and the shift in the main cause of mortality in patients with acromegaly are also addressed.

The Endothelium in Acromegaly

Growth hormone (GH) and insulin like growth factor-1 (IGF-1) excess induce well-known deleterious effects on the cardiovascular system, especially after long-term exposition. Acromegaly, a condition of chronic GH and IGF-1 hypersecretion, is frequently associated to cardiovascular complications, although recent studies have shown a reduction in the prevalence of these comorbidities in well-controlled patients and a mortality risk similar to normal aging population. Many factors could contribute to the increased cardiovascular risk of acromegaly patients. Among these factors, the endothelium plays a key role in the pathogenesis of atherosclerotic plaques and could be considered an early marker of atherosclerosis and cardiovascular dysfunction. In this review we examined the relationship between GH/IGF-1 excess and the endothelium, from basic studies to clinical evidence. Many studies involving various arterial districts (microvascular arteries of retina, kidney and brain, and major vessels as carotid and aorta) showed that GH/IGF-1 excess promotes endothelial dysfunction via several different mechanisms. Increased endothelial proliferation, dysfunction of endothelial progenitor cells, increased oxidative stress, and compromised oxidative defenses are the main factors that are associated with endothelial dysfunction. In the general population, these alterations are associated with the development of atherosclerosis with an increased incidence of coronary artery disease and cerebrovascular complications. However, in acromegaly this is still a debated issue, despite the presence of many pro-atherogenic factors and comorbidities, such as hypertension, diabetes, sleep apnoea, and metabolic syndrome. Preclinical markers of atherosclerosis as arterial intima media thickness, pulse wave velocity and flow mediated dilation seem to be impaired in acromegaly and partly mediated by the endothelium dysfunction. In conclusion, the pathophysiology of endothelial dysfunction in the condition of GH and IGF-1 excess remains a crucial area of investigation to fully dissect the association of acromegaly with cardiovascular disease complications.

Preclinical markers of atherosclerosis in acromegaly: a systematic review and meta-analysis

OBJECTIVE

Multiple studies investigated preclinical markers of peripheral vascular damage in acromegaly (ACRO) reporting discordant results. The aim of this study was to run a meta-analysis to examine whether intima media thickness (IMT), flow mediated dilation (FMD) and arterial pulse wave velocity (PWV) are affected in acromegalic patients and to assess the impact of effective treatment of growth hormone excess on these outcomes.

STUDY SELECTION

Twenty-seven studies comparing ACRO vs control (CON) populations and active (ACT) vs inactive (INACT) ACRO were included in the meta-analysis.

DATA SYNTHESIS

ACRO compared to CON have higher IMT (ES = 0.83, 95% C.I. 0.35-1.30), p = 0.001, impaired FMD (ES = - 1.59, 95% C.I. - 2.33 to - 0.85, p < 0.0001) and higher PWV (ES = 0.76 95% C.I. 0.37-1.16, p = 0.0001). When patients with ACT vs INACT disease were considered IMT was higher (ES = 0.43, 95% C.I. 0.02-0.84, p = 0.041) and FMD was impaired (ES = - 0.66, 95% C.I. - 1.28 to 0.04, p = 0.038) in ACT patients. Meta-regression analysis of studies comparing IMT in ACT vs INACT acromegalic patients showed a significant and inverse association between the effect size and the percent of hypertensive (p = 0.025) and diabetic (p = 0.041) patients.

CONCLUSIONS

IMT, FMD and arterial stiffness are impaired in acromegaly showing that these patients may be at increased risk of atherosclerosis. In patients with active disease these preclinical markers of atherosclerosis are worse compared to patients with inactive disease but the role of diabetes and hypertension is prevailing on growth hormone excess.