Hypertension in Acromegaly in Relationship to Biochemical Control and Mortality: Global ACROSTUDY Outcomes

Disease control of acromegaly does not prevent excess mortality in the long term: results of a nationwide survey in Italy

OBJECTIVE

This study aimed to assess the long-term outcome of patients with acromegaly.

DESIGN

This is a multicenter, retrospective, observational study which extends the mean observation period of a previously reported cohort of Italian patients with acromegaly to 15 years of follow-up.

METHODS

Only patients from the centers that provided information on the life status of at least 95% of their original cohorts were included. Life status information was collected either from clinical records or from the municipal registry offices. Standardized mortality ratios (SMRs) were computed comparing data with those of the general Italian population.

RESULTS

A total of 811 patients were included. There were 153 deaths, with 90 expected and an SMR of 1.7 (95% CI 1.4-2.0, p < 0.001). Death occurred after a median of 15 (women) or 16 (men) years from the diagnosis, without gender differences. Mortality remained elevated in the patients with control of disease (SMR 1.3, 95% CI 1.1-1.6). In the multivariable analysis, only older age and high IGF1 concentrations at last available follow-up visit were predictors of mortality. The oncological causes of death outweighed the cardiovascular ones, bordering on statistical significance with respect to the general population.

CONCLUSIONS

Mortality remains significantly high in patients with acromegaly, irrespectively of disease status, as long as the follow-up is sufficiently long with a low rate of patients lost to follow-up. Therapy strategy including radiotherapy does not have an impact on mortality. Oncological causes of death currently outweigh the cardiovascular causes.

Efficacy and Safety of Pegvisomant in the Treatment of Acromegaly

Pegvisomant, the first and currently only clinically available growth hormone receptor antagonist, is an effective therapeutic option for the medical treatment of acromegaly, a rare disorder characterized by excessive growth hormone secretion. With now over 20 years of real world experience, its safety and efficacy is well-established. However, several aspects of its clinical use are still controversially discussed. The high cost of pegvisomant has limited its use in several countries, and recent studies have reported a lower efficacy than the initial clinical trials. A reported increase in tumor volume under therapy varies between studies and has been attributed to either actual growth or re-expansion after cessation of somatostatin receptor ligand therapy. Furthermore, different combinations of pegvisomant and other therapeutic agents aiming at reduction of acromegaly disease activity have been proposed to increase or retain effectiveness while lowering side effects and cost. This review aims to assess current clinical data on the safety and efficacy of pegvisomant while also addressing controversies surrounding its use.

Clinical Biology of the Pituitary Adenoma

All endocrine glands are susceptible to neoplastic growth, yet the health consequences of these neoplasms differ between endocrine tissues. Pituitary neoplasms are highly prevalent and overwhelmingly benign, exhibiting a spectrum of diverse behaviors and impact on health. To understand the clinical biology of these common yet often innocuous neoplasms, we review pituitary physiology and adenoma epidemiology, pathophysiology, behavior, and clinical consequences. The anterior pituitary develops in response to a range of complex brain signals integrating with intrinsic ectodermal cell transcriptional events that together determine gland growth, cell type differentiation, and hormonal production, in turn maintaining optimal endocrine health. Pituitary adenomas occur in 10% of the population; however, the overwhelming majority remain harmless during life. Triggered by somatic or germline mutations, disease-causing adenomas manifest pathogenic mechanisms that disrupt intrapituitary signaling to promote benign cell proliferation associated with chromosomal instability. Cellular senescence acts as a mechanistic buffer protecting against malignant transformation, an extremely rare event. It is estimated that fewer than one-thousandth of all pituitary adenomas cause clinically significant disease. Adenomas variably and adversely affect morbidity and mortality depending on cell type, hormone secretory activity, and growth behavior. For most clinically apparent adenomas, multimodal therapy controlling hormone secretion and adenoma growth lead to improved quality of life and normalized mortality. The clinical biology of pituitary adenomas, and particularly their benign nature, stands in marked contrast to other tumors of the endocrine system, such as thyroid and neuroendocrine tumors.

Acromegaly: pathogenesis, diagnosis, and management

Growth hormone-secreting pituitary adenomas that cause acromegaly arise as monoclonal expansions of differentiated somatotroph cells and are usually sporadic. They are almost invariably benign, yet they can be locally invasive and show progressive growth despite treatment. Persistent excess of both growth hormone and its target hormone insulin-like growth factor 1 (IGF-1) results in a wide array of cardiovascular, respiratory, metabolic, musculoskeletal, neurological, and neoplastic comorbidities that might not be reversible with disease control. Normalisation of IGF-1 and growth hormone are the primary therapeutic aims; additional treatment goals include tumour shrinkage, relieving symptoms, managing complications, reducing excess morbidity, and improving quality of life. A multimodal approach with surgery, medical therapy, and (more rarely) radiation therapy is required to achieve these goals. In this Review, we examine the epidemiology, pathogenesis, diagnosis, complications, and treatment of acromegaly, with an emphasis on the importance of tailoring management strategies to each patient to optimise outcomes.

Effect of Diabetes on Morbidity and Mortality in Patients With Acromegaly

CONTEXT

Diabetes is a major risk factor for cardiovascular disease and death but its effect on outcomes in acromegaly is unknown.

OBJECTIVE

This work aimed to study whether diabetes affects morbidity and mortality in patients with acromegaly.

METHODS

A nationwide (Sweden), observational, matched-cohort study was conducted. Patients diagnosed with acromegaly between 1987 and 2020 were identified in the Swedish National Patient Registry and those with concomitant type 2 diabetes in the National Diabetes Registry and Drug Registry. The risk of overall mortality, and cardiovascular mortality and morbidity were estimated using Cox regression.

RESULTS

The study included 254 patients with acromegaly and concomitant type 2 diabetes (ACRO-DM group) and 532 without diabetes (ACRO group). Mean (SD) age at baseline was 62.6 (11.4) and 60.0 (12.1) years (P = .004) and the mean (SD) duration of acromegaly was 6.8 (8.1) and 6.0 (6.2) years (P = .098) in the ACRO-DM and ACRO groups, respectively. Overall mean follow-up was 9.2 years. The unadjusted overall mortality rate per 1000 person-years was 35.1 (95% CI, 27.2-44.7) and 20.1 (95% CI, 16.5-24.3) in the respective groups. The hazard ratio (HR) for overall mortality adjusted for multiple confounders was 1.58 (95% CI, 1.12-2.23) in the ACRO-DM group compared with the ACRO group. Cardiovascular mortality (HR 2.11; 95% CI, 1.09-4.10) and morbidity (HR 1.49; 95% CI, 1.21-1.82) were also increased in the ACRO-DM group.

CONCLUSION

The presence of diabetes in patients with acromegaly was associated with increased overall mortality as well as increased cardiovascular mortality and morbidity.

Acromegaly and pregnancy: a systematic review and meta-analysis

PURPOSE

To evaluate the association between acromegaly and pregnancy in terms of disease activity, maternal and fetal outcomes.

METHODS

This systematic review was conducted according to the Joanna Briggs Institute methodology for systematic reviews of etiology and risk. We focused on observational studies that included pregnant women with acromegaly. The outcomes were acromegaly activity, preterm birth, gestational diabetes, hypertension, eclampsia/preeclampsia, miscarriage, perinatal mortality, low birthweight, small for gestational age, and congenital malformations. Embase, Medline, LILACS, and CENTRAL were our source databases. To perform proportional meta-analyses, we used Stata Statistical Software 17.

RESULTS

Nineteen studies were included encompassing a total of 273 pregnancies in 211 women with acromegaly. The overall frequency of control of acromegaly during pregnancy was 62%, and of tumor growth was 9%. No fetal or maternal deaths were reported. The overall frequency of worsening of previous diabetes or development of gestational diabetes was 9%, and of previous hypertension or preeclampsia/eclampsia was 6%. The overall frequency of premature labor was 9% [from 17 studies of 263 pregnancies; 95% confidence interval (CI), 5-13%]; of spontaneous miscarriage was 4% (from 19 studies of 273 pregnancies; 95% CI, 2-11%); of small for gestational age was 5% (from 15 studies of 216 newborns; 95% CI, 3-9%); and of congenital malformations was 1% (from 18 studies of 240 newborns; 95% CI, 0-7%).

CONCLUSION

Pregnancy in women with acromegaly is frequently associated with disease control and is safe in relation to fetal and maternal outcomes, as in women without acromegaly.

Prevalence of comorbidities and concomitant medication use in acromegaly: analysis of real-world data from the United States

PURPOSE

Patients receiving treatment for acromegaly often experience significant associated comorbidities for which they are prescribed additional medications. We aimed to determine the real-world prevalence of comorbidities and concomitant medications in patients with acromegaly, and to investigate the association between frequency of comorbidities and number of concomitantly prescribed medications.

METHODS

Administrative claims data were obtained from the IBM® MarketScan® database for a cohort of patients with acromegaly, identified by relevant diagnosis codes and acromegaly treatments, and a matched control cohort of patients without acromegaly from January 2010 through April 2020. Comorbidities were identified based on relevant claims and assessed for both cohorts.

RESULTS

Overall, 1175 patients with acromegaly and 5875 matched patients without acromegaly were included. Patients with acromegaly had significantly more comorbidities and were prescribed concomitant medications more so than patients without acromegaly. In the acromegaly and control cohorts, respectively, 67.6% and 48.4% of patients had cardiovascular disorders, the most prevalent comorbidities, and 89.0% and 68.3% were prescribed > 3 concomitant medications (p < 0.0001). Hypopituitarism and hypothalamic disorders, sleep apnea, malignant neoplasms and cancer, and arthritis and musculoskeletal disorders were also highly prevalent in the acromegaly cohort. A moderate, positive correlation (Spearman correlation coefficient 0.60) was found between number of comorbidities and number of concomitant medications in the acromegaly cohort.

CONCLUSION

Compared with patients without acromegaly, patients with acromegaly have significantly more comorbidities and are prescribed significantly more concomitant medications. Physicians should consider the number and type of ongoing medications for individual patients before prescribing additional acromegaly treatments.

Renal effects of growth hormone in health and in kidney disease

Growth hormone (GH) and its mediator insulin-like growth factor-1 (IGF-1) have manifold effects on the kidneys. GH and IGF receptors are abundantly expressed in the kidney, including the glomerular and tubular cells. GH can act either directly on the kidneys or via circulating or paracrine-synthesized IGF-1. The GH/IGF-1 system regulates glomerular hemodynamics, renal gluconeogenesis, tubular sodium and water, phosphate, and calcium handling, as well as renal synthesis of 1,25 (OH)2 vitamin D3 and the antiaging hormone Klotho. The latter also acts as a coreceptor of the phosphaturic hormone fibroblast-growth factor 23 in the proximal tubule. Recombinant human GH (rhGH) is widely used in the treatment of short stature in children, including those with chronic kidney disease (CKD). Animal studies and observations in acromegalic patients demonstrate that GH-excess can have deleterious effects on kidney health, including glomerular hyperfiltration, renal hypertrophy, and glomerulosclerosis. In addition, elevated GH in patients with poorly controlled type 1 diabetes mellitus was thought to induce podocyte injury and thereby contribute to the development of diabetic nephropathy. This manuscript gives an overview of the physiological actions of GH/IGF-1 on the kidneys and the multiple alterations of the GH/IGF-1 system and its consequences in patients with acromegaly, CKD, nephrotic syndrome, and type 1 diabetes mellitus. Finally, the impact of short- and long-term treatment with rhGH/rhIGF-1 on kidney function in patients with kidney diseases will be discussed.

Descriptive Epidemiology and Survival Analysis of Acromegaly in Korea

BACKGROUND

Acromegaly is a rare, slowly progressive disease. Its mechanism is not fully understood, and epidemiological research on Korean patients with acromegaly is scarce. The purpose of this study was to determine the incidence and prevalence of acromegaly and assess the comorbidities and survival benefits based on treatment options.

METHODS

This nationwide population-based cohort study was conducted using data of the Korean Health Insurance Review and Assessment claims database to evaluate the incidence of newly diagnosed acromegaly cases during 2013-2017.

RESULTS

During the 5-year period, 1,093 patients were newly diagnosed with acromegaly. The average annual incidence was 4.2 cases per million per year, and the prevalence was 32.1 cases per million during this period. The incidence of hypertension was low after medical treatment (hazard ratio, 0.257; 95% confidence interval, 0.082-0.808; P = 0.020), but the incidence of diabetes showed no significant difference across treatment modalities. Over a period of 6 years since diagnosis, we found that patients treated for acromegaly had a significantly higher survival rate than those untreated (P < 0.001).

CONCLUSION

The annual incidence rate of Korean patients with acromegaly was similar to that reported in previous studies. Using nationwide population data, our study emphasized the importance of treatment in acromegaly patients.

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.