Three noninvasive methods in the evaluation of subclinical cardiovascular disease in patients with acromegaly: epicardial fat thickness, aortic stiffness and serum cell adhesion molecules

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.

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.

Follow-Up Study of Growth Hormone Therapy in Children with Kabuki Syndrome: Two-Year Treatment Results

INTRODUCTION

Kabuki syndrome (KS) is a genetic disorder with characteristic facial dysmorphisms, short stature, hypertension, and obesity later in life. The aim of this study was to evaluate catch-up growth and cardiovascular markers before and during growth hormone (rhGH) treatment in KS children.

METHODS

This prospective study included 18 children whose KS was genetically established. Each KS subject received rhGH for a period of 2 years. Several measurements were performed before and during treatment: anthropometry, glucose metabolism, lipid profile, markers for endothelial function, and low-grade inflammation.

RESULTS

This study found an increase in delta height standard deviation score (SDS) for the whole group of 1.1 SDS after 2 years of rhGH treatment. Baseline metabolic profiles showed no cardiometabolic abnormalities in these children. Although 4 out of 18 children were obese, there were no signs of the metabolic syndrome. During rhGH treatment, serum low-density lipoprotein cholesterol concentrations decreased significantly (2.16-1.91 mmol/L, p = 0.04). Apolipoprotein B100 concentrations also showed a reduction after 24 months of treatment, but the other lipid and (apo)lipoprotein parameters did not change. While other endothelial function markers were stable, only vascular cell-adhesion molecule-1 concentrations increased (1,084-1,161 pg/mL, p < 0.01) during rhGH therapy. Furthermore, BMI and waist circumference improved during treatment. There were no signs of hypertension.

CONCLUSIONS

At baseline and during rhGH therapy, there were no signs of the metabolic syndrome. This is the first study demonstrating that rhGH treatment in KS children is a safe and effective therapy and that it positively influences linear height without exerting adverse effects on a wide array of cardiovascular risk markers.

Effects of Long-Acting Somatostatin Analogues on Lipid Metabolism in Patients with Newly Diagnosed Acromegaly: A Retrospective Study of 120 Cases

The short-term effects of long-acting somatostatin analogues (SSAs) on lipid profiles in patients with acromegaly are not well studied. We retrospectively analyzed the effects of SSAs on lipid profiles and associated cardiovascular risk factors in a cohort of 120 newly diagnosed acromegaly patients. In this study, 69 females and 51 males were included. These patients were treated with either octreotide LAR (OCT) or lanreotide SR (LAN) for 3 months. After SSAs treatment, both GH and IGF-1 significantly decreased (p<0.001). Triglyceride (TG), total to high-density lipoprotein cholesterol (HDL-C) ratio, and lipoprotein (a) [Lp(a)] levels were significantly decreased, while HDL-C levels were increased (p<0.05). The reduction of mean serum GH (GH_m) was positively associated with the decrease of TG (r=0.305, p=0.001) and Lp(a) (r=0.257, p=0.005), as well as the increase of HDL-C (r=-0.355, p<0.001). The changes of lipid profiles were observed only in OCT group, but not in LAN group. In addition, systolic blood pressure (SBP) had significantly declined after SSAs treatment, with an average reduction of 4.4 mmHg (126.7±1.28 vs. 122.3±1.44 mmHg, p=0.003), while no change was observed regarding diastolic blood pressure (DBP) (p>0.05). Fasting insulin, fasting C-peptide, and HOMA-IR were significantly decreased after SSAs treatment. In conclusion, our current study revealed that short-term SSAs treatment improves lipid profiles and other cardiovascular risk factors in patients with acromegaly.

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.

The association between treatment and systemic inflammation in acromegaly

OBJECTIVE

Acromegaly is characterized by an excess of growth hormone (GH) and insulin like growth-factor 1 (IGF1), and it is strongly associated with cardiovascular diseases (CVD). Both acute and long-lasting pro-inflammatory effects have been attributed to IGF1. Previous results suggest the presence of systemic inflammation in treated patients. Here we assessed the association between treatment of acromegaly, systemic inflammation and vascular function.

DESIGN

Ex vivo cytokine production and circulating inflammatory markers were assessed in peripheral blood from treated and untreated acromegaly patients (N = 120), and compared them with healthy controls. A more comprehensive prospective inflammatory and vascular assessment was conducted in a subgroup of six treatment-naive patients with follow-up during treatment.

RESULTS

Circulating concentrations of VCAM1, E-selectin and MMP2 were higher in patients with uncontrolled disease, whereas the concentrations of IL18 were lower. In stimulated whole blood, cytokine production was skewed towards a more pro-inflammatory profile in patients, especially those with untreated disease. Prospective vascular measurements in untreated patients showed improvement of endothelial function during treatment.

CONCLUSIONS

Acromegaly patients are characterized by a pro-inflammatory phenotype, most pronounced in those with uncontrolled disease. Treatment only partially reverses this pro-inflammatory bias. These findings suggest that systemic inflammation could contribute to the increased risk of CVD in acromegaly patients.

Growth hormone control and cardiovascular function in patients with acromegaly

BACKGROUND

Acromegaly is associated with cardiovascular alterations. Up to 50% acromegalic patients suffered from treatment failure after multiple modalities. We investigated correlation between cardiovascular function and control of growth hormone (GH) in acromegalic patients following transsphenoidal adenomectomy (TSA).

METHODS

We recruited acromegalic patients who had undergone TSA between 2006 and 2014 in this cross-sectional study. Patients were assigned to group 1, controlled acromegaly (GH <1.0 ng/mL and normalized insulin-like growth factor-1 [IGF-1]); group 2, partially controlled acromegaly (either GH >1.0 ng/mL or non-normalized IGF-1); or group 3, uncontrolled acromegaly (GH >1.0 ng/mL and non-normalized IGF-1). Echocardiography evaluated the left ventricular mass index, left ventricular ejection fraction, and the early transmitral filling velocity (E)-to-late transmitral filling velocity (A) and the E-to-the early diastolic mitral annular velocity (E') ratios. Carotid tonometry evaluated the intima-media thickness of the carotid artery, carotid-femoral pulse wave velocity, augmentation index, aortic characteristic impedance (Zc), and pulse pressure amplification.

RESULTS

Thirty-three patients participated in this study. Fourteen of the 33 patients were males (42%). Mean age at diagnosis was 50.33 years (SD 18.45). Compared to patients in group 1, patients in group 3 had younger age and shorter years after operation, without statistical significance. Cumulative GH levels were progressively higher from group 1 to group 3, without statistical significance. The groups did not differ with respect to cardiovascular structure and function evaluated by echocardiography and carotid tonometry. Only Zc value had a difference that was of borderline significance (group 1: 109.13 ± 32.99; group 2: 129.30 ± 32.27; group 3: 159.56 ± 77.4 dynes × s/cm5; ANOVA p = 0.088; p = 0.086 for group 1 vs group 3).

CONCLUSION

In the patients with acromegaly who had undergone TSA, cardiac structure and vascular stiffness did not differ among the groups with different levels of GH control.

Acromegaly, inflammation and cardiovascular disease: a review

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.

Cardiac CT scanning in coronary artery disease: Epicardial fat volume and its correlation with coronary artery lesions and left ventricular function

Coronary artery disease (CAD) is a major and common disease that poses a threat to human health. Recent studies suggested that epicardial fat may have an important role in the pathogenesis of CAD. Therefore, the association between epicardial fat volume (EFV) and left ventricular function with CAD was investigated in the present study. A total of 61 patients with suspected CAD who underwent CT scanning were enrolled. Baseline data, parameters of left heart function and EFV of the subjects were collected and analyzed. The degree of coronary artery lesions was assessed using the Gensini score. Pearson's correlation analysis and a logistic regression model were applied to assess the association between EFV and risk factors for CAD, the Gensini score and left ventricular function index. A total of 29 female and 32 male subjects with a median age of 63 years were enrolled. The median body mass index (BMI) of the subjects was 23.37 kg/m² and the median EFV was 86.41 cm³. It was revealed that risk factors of CAD, specially hypertension, diabetes mellitus, dyslipidemia, history of myocardial infarction and smoking, had no significant association with the EFV (P>0.05); however, the EFV was significantly positively correlated with the BMI (r=0.479, P<0.0001), interventricular septal thickness (r=0.436, P=0.004), left ventricular posterior wall thickness (r=0.350, P=0.0058), left ventricular end diastolic diameter (r=0.265, P=0.0388), left ventricular mass (r=0.445, P=0.0003) and left ventricular mass index (r=0.371, P=0.0035). However, no correlation was identified between the EFV and the Gensini score (r=0.131, P=0.3137). In conclusion, the EFV measured by cardiac CT scanning was positively correlated with the BMI and left ventricular function, but was not associated with the presence of CAD according to the Gensini scores.

Increased circulating levels of irisin are associated with cardiovascular risk factors in subjects with acromegaly

AIMS

Irisin, a peptide secreted from muscle and adipose tissues, is associated with insulin resistance as well as metabolic and cardiovascular diseases. Acromegaly is a rare disorder caused by overproduction of growth hormone (GH) and is associated with functional and structural differentiation of adipose and muscle tissues. Acromegalic subjects are also at risk of vascular diseases and metabolic dysfunctions. We aimed to determine the altered levels of irisin in subjects with active acromegaly and controlled acromegaly and in controls, and to ascertain whether there is an association between irisin and hormonal and cardiometabolic parameters.

METHODS

We enrolled 40 subjects with active acromegaly, 30 subjects with controlled acromegaly, and 40 control subjects of matched age, gender, BMI, and occurrence of hypertension, diabetes, and metabolic syndrome distribution in the present cross-sectional study. Hormonal and metabolic parameters, carotid intima media thickness (cIMT), and epicardial fat thickness (EFT) of the subjects were evaluated. Irisin levels were measured using ELISA.

RESULTS

Circulating levels of irisin were significantly higher in acromegalic subjects compared to both controlled acromegalic subjects and controls. Moreover, irisin levels were elevated in controlled acromegalic subjects compared to controls. Irisin displayed a positive correlation with insulin resistance, cIMT, EFT, BMI, GH, and insulin-like growth factor (IGF-1) in acromegalic subjects. Irisin levels were independently associated with cIMT and EFT according to multiple regression analyses. There was an independent relationship between irisin and IGF-1.

CONCLUSIONS

Elevated irisin levels in acromegalic subjects were associated with cIMT and EFT, suggesting that irisin is a surrogate marker for cardiovascular risk in acromegalic subjects.

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.

Current perspectives on the impact of clinical disease and biochemical control on comorbidities and quality of life in acromegaly

Acromegaly is a rare chronic, systemic disorder caused by excessive growth hormone (GH) secretion from a somatotroph pituitary adenoma. GH hypersecretion leads to overproduction of insulin-like growth factor-1 (IGF-1), which contributes to the somatic overgrowth, physical disfigurement, onset of multiple systemic comorbidities, reduced quality of life (QoL) and premature mortality of uncontrolled patients. Somatostatin receptor ligands, dopamine agonists and a GH receptor antagonist are currently available for medical therapy of acromegaly. The main aim of treatment is biochemical normalisation, defined as age-normalised serum IGF-1 values and random GH levels <1.0 μg/L. However, there is an increasing evidence suggesting that achieving biochemical control does not always decrease the burden of disease-related comorbidities and/or improve patients' QoL. This lack of correlation between biochemical and clinical control can be due to both disease duration (late diagnosis) or to the peculiarity of a given comorbidity. Herein we conducted ad hoc literature searches in order to find the most recent and relevant reports on biochemical and clinical disease control during medical treatment of acromegaly. Particularly, we analyse and describe the relationship between biochemical, as well as clinical disease control in patients with acromegaly receiving medical therapy, with a focus on comorbidities and QoL. In conclusion, we found that current literature data seem to indicate that clinical disease control (besides biochemical control), encompassing clinical signs and symptoms, comorbidities and QoL, emerge as a primary focus of acromegaly patient management.

Changes in metabolic parameters and cardiovascular risk factors after therapeutic control of acromegaly vary with the treatment modality. Data from the Bicêtre cohort, and review of the literature

CONTEXT

Untreated acromegaly is associated with increased morbidity and mortality due to malignant, cardiovascular, and cerebrovascular disorders. Effective treatment of acromegaly reduces excess mortality, but its impact on cardiovascular risk factors and metabolic parameters are poorly documented.

AIM

We analyzed changes in cardiovascular risk factors and metabolic parameters in patients receiving various treatment modalities.

PATIENTS AND METHODS

We retrospectively studied 96 patients with acromegaly, both at diagnosis and after IGF-I normalization following surgery alone (n = 51) or medical therapy with first generation somatostatin analogues (SSA, n = 23), or pegvisomant (n = 22). Duration of follow-up was 77 (42-161) months, 75 (42-112) months, and 62 (31-93) months, in patients treated with surgery alone, SSA, and pegvisomant, respectively. In all the cases except four, patients treated medically had underwent previous unsuccessful surgery.

RESULTS

IGF-I normalization was associated with increased body weight, decreased systolic blood pressure (SBP) in hypertensive patients, decreased fasting plasma glucose (FPG) and HOMA-IR and HOMA-B levels, increased HDL cholesterol (HDLc); whereas, LDL cholesterol (LDLc) was not significantly different. Plasma PCSK9 levels were unchanged in patients with available values. Cardiovascular and metabolic changes varied with the treatment modality: surgery, but not pegvisomant, had a beneficial effect on SBP; FPG decreased after surgery but increased after SSA; the decline in HOMA-IR was only significant after surgery; pegvisomant significantly increased LDLc and total cholesterol; whereas SA increased HDLc and had no effect on LDLc levels.

CONCLUSION

Treatments used to normalize IGF-I levels in patients with acromegaly could have differential effects on cardiovascular risk factors and metabolic parameters.

Is elevated urotensin II level a predictor for increased cardiovascular risk in subjects with acromegaly?

PURPOSE

Acromegaly is a rare disorder existed in the result of overproduction of growth hormone (GH). The disorder is associated with increased cardiovascular risk factors and metabolic abnormalities. Urotensin II (UII), a secreted vasoactive peptide hormone, belonging somatostatin superfamily, plays an essential role in atherosclerosis and glucose metabolism. The aim of this study was to ascertain whether circulating UII levels are altered in subjects with acromegaly, and to describe the relationship between UII and hormonal or cardiometabolic parameters.

METHODS

This cross-sectional study included 41 subjects with active acromegaly, 28 subjects with controlled acromegaly, and 37 age- and BMI-matched controls without acromegaly. Hormonal and metabolic features of the subjects as well as carotid intima media thickness (cIMT) and epicardial fat thickness (EFT) were defined. Circulation of UII levels was determined via ELISA.

RESULTS

Both active and controlled acromegalic subjects showed a significant elevation of circulating levels of UII with respect to controls. There was no remarkable difference in circulating levels of UII between active and controlled acromegalic groups. Both cIMT and EFT were remarkably increased in acromegaly subjects comparing to controls. UII positively correlated with cIMT, EFT, BMI, and HOMA-IR. There was no correlation between UII and GH, insulin-like growth factor-1. According to the results obtained from regression models, UII levels independently predicted cIMT and EFT.

CONCLUSION

Elevated UII levels are associated with severity of cardiovascular risk factors including cIMT and EFT in acromegalic subjects.

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.

Bringing Cardiovascular Comorbidities in Acromegaly to an Update. How Should We Diagnose and Manage Them?

Patients with acromegaly frequently develop cardiovascular comorbidities, which significantly affect their morbidity and contribute to an increased all-cause mortality. In this regard, the most frequent complications that these patients may encounter include hypertension, cardiomyopathy, heart valve disease, arrhythmias, atherosclerosis, and coronary artery disease. The specific underlying mechanisms involved in the pathophysiology of these comorbidities are not always fully understood, but uncontrolled GH/IGF-I excess, age, prolonged disease duration, and coexistence of other cardio-vascular risk factors have been identified as significant influencing predisposing factors. It is important that clinicians bear in mind the potential development of cardiovascular comorbidities in acromegalic patients, in order to promptly tackle them, and avoid the progression of cardiac abnormalities. In many cases, this approach may be performed using straightforward screening tools, which will guide us for further diagnosis and management of cardiovascular complications. This article focuses on those cardiovascular comorbidities that are most frequently encountered in acromegalic patients, describes their pathophysiology, and suggests some recommendations for an early and optimal diagnosis, management and treatment.

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.

CARDIOVASCULAR COMPLICATIONS OF ACROMEGALY

Acromegaly is associated with increased mortality and decreased life expectancy. Cardiovascular disease is the principal cause of premature mortality in patients with acromegaly, accounting for about 60% of deaths. GH and/or IGF-I exert direct cardiac effects: enhance cardiac contractility, stimulate cardiomyocyte growth, influence calcium influx in cardiomyocytes. Cardiac remodelling is influenced by hypertension and insulin resistance. Among cardiovascular risk factors arterial hypertension, reported in 35% of patients with acromegaly, ranks among most important negative prognostic factors for mortality. Hypertension plays significant role in the development of cardiac hypertrophy, especially in older acromegalic patients and diastolic blood pressure is best predictive factor for cardiac hypertrophy. Therefore, early and aggressive hypertension treatment is essential for prognosis in acromegaly. Other important risk factors are: valvular defects, arrhythmias, endothelial dysfunction, heart failure, lipid abnormalities and coronary artery disease. Numerous studies suggest that patients with acromegaly are under threat of arrhythmias, especially those with structural heart abnormalities. Congestive heart failure as end-stage acromegalic cardiomyopathy occurs usually in older patients, with long-term uncontrolled disease and other cardiovascular and metabolic complications. Relation between acromegaly and coronary artery disease is controversial as it seems to be connected rather with classical cardiovascular risk factors than GH and IGF-1 overexpresion.

Complications of acromegaly: cardiovascular, respiratory and metabolic comorbidities

Acromegaly is associated with an enhanced mortality, with cardiovascular and respiratory complications representing not only the most frequent comorbidities but also two of the main causes of deaths, whereas a minor role is played by metabolic complications, and particularly diabetes mellitus. The most prevalent cardiovascular complications of acromegaly include a cardiomyopathy, characterized by cardiac hypertrophy and diastolic and systolic dysfunction together with arterial hypertension, cardiac rhythm disorders and valve diseases, as well as vascular endothelial dysfunction. Biochemical control of acromegaly significantly improves cardiovascular disease, albeit completely recovering to normal mainly in young patients with short disease duration. Respiratory complications, represented mainly by sleep-breathing disorders, particularly sleep apnea, and respiratory insufficiency, frequently occur at the early stage of the disease and, although their severity decreases with disease control, this improvement does not often change the indication for a specific therapy directed to improve respiratory function. Metabolic complications, including glucose and lipid disorders, are variably reported in acromegaly. Treatments of acromegaly may influence glucose metabolism, and the presence of diabetes mellitus in acromegaly may affect the choice of treatments, so that glucose homeostasis is worth being monitored during the entire course of the disease. Early diagnosis and prompt treatment of acromegaly, aimed at obtaining a strict control of hormone excess, are the best strategy to limit the development or reverse the complications and prevent the premature mortality.

Cystatin-C and epicardial adipose tissue as noninvasive predictors of cardiovascular risk in acromegaly

BACKGROUND

Acromegaly (ACRO) is associated with elevated cardiovascular risk, although the prevalence of coronary artery disease (CAD) is unclear. Increased epicardial adipose tissue (EAT) and elevated cystatin-C (Cys-C) levels are cardiovascular risk factors, also related to the progression of CAD in several populations.

AIMS

To measure the severity and extent of CAD in patients with ACRO and to determine whether either EAT or Cys-C reflect higher cardiovascular risk in patients with ACRO than in healthy controls.

SUBJECTS AND METHODS

Case-control study, of 35 patients with ACRO (19 males, 17 with active disease) and 35 age-, gender- and body mass index (BMI)-matched healthy controls; mean age was 48·1 ± 8·1 years and mean BMI was 27·6 ± 4·8 kg/m² . Cys-C was measured by an immunoturbidimetric assay. The 10-year risk of developing a coronary event was calculated using the Framingham Risk Score (FRS). EAT index (volume indexed to body surface area), and severity and extent of CAD were measured using a 256-slice multidetector computed tomography scanner (iCT-256 Philips Healthcare, Amsterdam).

RESULTS

Coronary artery disease lesions, EAT index and severity/extent of CAD were similar between patients with ACRO and controls. Forty-four per cent of patients with ACRO had mild coronary lesions associated with greater EAT index (ß = 0·022, P = 0·036). Cys-C levels correlated with both EAT index (ρ = 0·386, P = 0·031) and FRS (ρ = 0·477, P = 0·004) in patients with ACRO only, despite similar prevalence of traditional cardiovascular risk factors. In a multiple linear regression model, both Cys-C levels (ß = 0·369, P = 0·007) and EAT index (ß = 0·29, P = 0·025) predicted FRS (R² = 0·613).

CONCLUSIONS

In patients with ACRO, both Cys-C and EAT index might be used as noninvasive predictors of cardiovascular risk.

Pro-atherogenic mediators and subclinical atherogenesis are related to epicardial adipose tissue thickness in patients with cardiovascular risk

Objective

To evaluate the relationship between pro-atherogenic biomarkers and epicardial adipose tissue (EAT) thickness in patients with cardiovascular risk factors.

Methods

Plasma nitric oxide (NO), soluble intercellular adhesion molecule-1 and malondialdehyde (MDA) levels, EAT thickness, flow-mediated dilation (FMD) and carotid intima media thickness (CIMT) were determined in patients aged >18 years who were referred for echocardiography for heart ischemia or non-ischemic diseases. Cardiovascular risk factors (Framingham score [FS] ≥ 20) were weighted.

Results

Hypertension, dyslipidaemia and type 2 diabetes mellitus were prevalent (≥55% of 40 patients). Patients with FS ≥ 20 (n = 21) showed significantly higher EAT and CIMT values. Globally, MDA, CIMT, age, waist circumference, high-density lipoprotein cholesterol (HDL-C) and FS were associated with EAT thickness. EAT was significantly associated with NO in patients with FS ≥ 20. Significant differences in EAT thickness were found between patients stratified by NO value, FMD, age, smoking status, dyslipidaemia, type 2 diabetes mellitus and FS. An EAT-associated atherogenic risk (CIMT ≥ 1 mm) model was statistically significant when MDA and type 2 diabetes mellitus were included.

Conclusion

EAT thickness was associated with MDA, CIMT, age, waist circumference, HDL-C and FS globally, but with NO only in patients with FS≥20. EAT may be used to identify vascular damage stage, possibly influenced by MDA and type 2 diabetes mellitus.

Markers of early atherosclerosis, oxidative stress and inflammation in patients with acromegaly

PURPOSE

Data regarding atherosclerosis in acromegaly is controversial in literature. We aimed to investigate the markers of early atherosclerosis, oxidative stress, inflammation and their relationships with each other in acromegaly.

METHODS

Thirty-nine patients with acromegaly and 40 control subjects were enrolled. Patients were classified into two groups; active acromegaly (AA) and controlled acromegaly (CA). Controls were matched by age, gender, body mass index and presence of cardiovascular risk factors. Flow mediated dilatation (FMD), carotid intima media thickness (CIMT), epicardial adipose tissue thickness (EAT) were measured and serum levels of oxidative stress parameters, high mobility group box 1 protein (HMGB1) and high sensitive CRP (hs CRP) were evaluated.

RESULTS

Significantly decreased FMD, increased CIMT and EAT were found in patients with acromegaly compared to controls (p < 0.01, p < 0.05, p < 0.001, respectively). EAT correlated negatively with FMD (r = -0.24, p = 0.038) and positively with CIMT (r = 0.37, p < 0.01). Presence of acromegaly, hypertension and age were found to be the predictors of early atherosclerosis (p < 0.05). Hs CRP was decreased in AA compared to controls (p = 0.01). There were no significant differences for HMGB1 and oxidized LDL (ox-LDL) cholesterol levels and total antioxidant capacity (TAC) between AA, CA and controls (p > 0.05).

CONCLUSION

Early atherosclerosis measured with FMD, CIMT and EAT may exist in acromegaly. However, decreased hs CRP and unchanged HMGB1, ox-LDL and TAC levels suggest that inflammation and oxidative stress do not seem to contribute to the development of atherosclerosis in these patients.

Evaluation of blood neutrophil to lymphocyte and platelet to lymphocyte ratios according to plasma glucose status and serum insulin-like growth factor 1 levels in patients with acromegaly

INTRODUCTION

Cardiovascular, respiratory, and cerebrovascular diseases and malignancies are responsible for morbidity and mortality in acromegaly. Also these diseases are associated with chronic inflammation. The neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) are currently gaining interest as new markers of inflammation. Moreover, increased morbidity and mortality are positively correlated with the presence of diabetes and levels of insulin-like growth factor 1 (IGF-1) in acromegaly. The objective of the present study was to investigate the relationship between these markers and acromegaly according to plasma glucose status and serum IGF-1 levels.

MATERIALS AND METHODS

We retrospectively analyzed data from 61 acromegaly patients who were in a newly diagnosed period (35 male, 26 female; mean age 38.13 ± 13.98). Patients with normal plasma glucose (n = 27), impaired fasting glucose (n = 18), and diabetes mellitus (n = 16) were categorized into three different groups. NLR and PLR were compared between the study groups and were evaluated according to IGF-1 levels.

RESULTS

There were no statistically significant differences in NLR and PLR measurements among the study groups (p > 0.05). However, there were significant positive correlations between NLR and IGF-1 levels and between PLR and IGF-1 levels when all patients were evaluated (r = 0.334, p = 0.011 and r = 0.277, p = 0.035, respectively).

CONCLUSIONS

This is the first report studying the relationship of NLR and PLR with glucose status and IGF-1 levels in acromegaly patients. Our study results suggest that subclinical inflammation may play a role in increased incidence of mortality and morbidity, which depends on uncontrolled IGF-1 levels in patients with acromegaly.