Prevalence of the sleep apnea syndrome in acromegaly population

High prevalence of severe sleep cycle disruption in de novo acromegaly and underdiagnosis by common clinical screening tools: A prospective, observational, cross-sectional study

CONTEXT

Although sleep disordered breathing (SDB) is well-recognised in acromegaly, most studies have reported heterogeneous, often heavily treated, groups and few have performed detailed sleep phenotyping at presentation.

OBJECTIVE

To study SDB using the gold standard of polysomnography, in the largest group of newly-diagnosed, treatment-naïve patients with acromegaly.

SETTING AND PATIENTS

40 patients [22 males, 18 females; mean age 54 years (range 23-78)], were studied to: (i) establish the prevalence and severity of SDB (ii) assess the reliability of commonly employed screening tools [Epworth Sleepiness Scale (ESS) and overnight oxygen desaturation index (DI)] to detect SDB (iii) determine the extent to which sleep architecture is disrupted.

RESULTS

Obstructive sleep apnoea (OSA), defined by the apnoea-hypopnoea index (AHI), was present in 79% of subjects (mild, n = 12; moderate, n = 5; severe, n = 14). However, in these individuals with OSA by AHI criteria, ESS (positive in 35% [n = 11]) and DI (positive in 71%: mild, n = 11; moderate, n = 6; severe, n = 5) markedly underestimated its prevalence/extent. Seventy-eight percent of patients exhibited increased arousal, with marked disruption of the sleep cycle, despite most (82%) having normal total time asleep. Fourteen patients spent longer in stage 1 sleep. Deeper sleep stages were severely attenuated in many subjects (reduced stage 2, n = 18; reduced slow wave sleep, n = 24; reduced rapid eye movement sleep, n = 32).

CONCLUSION

Our study provides strong support for clinical guidelines that recommend screening for sleep apnoea syndrome in patients with newly-diagnosed acromegaly. Importantly, however, it highlights shortcomings in commonly recommended screening tools (questionnaires, desaturation index) and demonstrates the added value of polysomnography to allow timely detection of obstructive sleep apnoea and associated sleep cycle disruption.

Global psychological assessment with the evaluation of life and sleep quality and sexual and cognitive function in a large number of patients with acromegaly: a cross-sectional study

OBJECTIVE

Acromegaly is associated with somatic disfigurements which impair self-perception of well-being and quality of life. Nowadays, limited data are available on the interplay between hormonal excess and psychological discomfort. The study aimed at investigating the psychological profile, sleep quality, sexual function, cognitive functions, and quality of life in patients with acromegaly.

METHODS

In 223 acromegaly patients from 5 referral centres, global psychological profile, sleep quality, sexual function, cognitive function, and quality of life were investigated.

RESULTS

Depression was found in ~30% of patients, and anxiety in two-thirds, together with severe discomfort in body image mainly in women. Obstructive sleep apnoea syndrome risk and sleep disorders were found in >50% of patients and daily sleepiness in ~20%. Sexual dysfunction was reported in most of the patients, with the most severe impairment in women. Cognitive functions were compromised in ~10% of cases. Disease duration and patient's age and gender were the main determinants of these psychopathological conditions. Depression (P = 0.047), somatic-affective mood lowering (P = 0.021), state (P < 0.001) and trait (P = 0.013) anxiety, and body image distortion in body uneasiness test A (P < 0.001) and B (P = 0.006) were significantly worsened in patients <45 years and slightly worsened in those with disease duration less than 2 years. Male (P < 0.001) and female (P < 0.001) sexual function scores were significantly worsened in patients aged >64 years and slightly worsened in those with disease duration for more than 10 years, particularly in presence of cardiometabolic and respiratory complications. Cognitive symptoms were slightly worsened in older patients and in those with long disease duration.

CONCLUSIONS

Acromegaly is associated with a relevant impairment of psychological profile persisting despite remission and long-term medical treatment.

A practical nutritional guideline to manage neuroendocrine neoplasms through chronotype and sleep

Chronotype is the attitude of subjects to carry out their daily activities mainly in the morning ("lark") or in the evening ("owl"). The intermediate chronotype is located between these two categories. It has been demonstrated that chronotype can influence the incidence, course and response to treatments of tumors. In particular patients diagnosed with gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) and evening chronotype are characterized by unhealthy lifestyle, obesity, metabolic syndrome, a worsen cardiometabolic profile, a poor prognosis with a progressive disease and the development of metastasis. In addition, evening chronotype has been associated with sleep disturbances, which in turn have been related to tumor development and progression of tumors. There is a strict connection between sleep disturbances and NENs because of the hyperactivation of proangiogenic factors that caused aberrant neoangiogenesis. A nutritional tailored approach could represent a tool to align subjects with evening chronotype to physiological biological rhythms based on the properties of some macro and micronutrients of being substrate for melatonin synthesis. Thus, we aimed to provide an overview on the association of chronotype categories and sleep disturbances with NENs and to provide nutritional advices to manage subjects with NENs and these disturbances of circadian rhythm.

Prevalence of sleep apnea and lung function abnormalities in patients with acromegaly

Background:

Sleep apnea (SA) is highly prevalent in acromegaly. Ethnicity influences the prevalence of SA in the general population. We studied the prevalence of SA and other respiratory comorbidities in North Indian patients with active acromegaly.

Design:

Prospective, observational.

Materials and Methods:

Consecutive adult patients with active acromegaly (n = 35, age 39.7 ± 13.2 years) and hypersomatotropism (nonsuppression of serum growth hormone after oral glucose and elevated serum insulin-like growth factor-1 [IGF-1]) were evaluated for respiratory symptoms, scoring for SA (Epworth Sleepiness Score [ESS] and STOP-BANG), pulmonary function tests (PFT), high-resolution computerized tomography (HRCT) of the thorax, polysomnography (PSG), and transthoracic echocardiography. Age- and sex-matched healthy individuals (n = 34) served as controls.

Results:

Acromegaly subjects had dyspnea (34%), cough (37%), excessive daytime somnolence (43%), and fatigue (49%). Clinically significant ESS (>10) and STOP-BANG score (≥3) were present in 41% and 68.6% of subjects, respectively. PFT showed restrictive and obstructive patterns in 45.7% and 11.4% of acromegalics respectively; with higher total lung capacity (TLC), thoracic gas volume (TGV), and residual volume (RV). PSG revealed significantly higher SA events in acromegalics (central [acromegaly 24.63 ± 37.82 vs. control 3.21 ± 5.5], mixed [11 ± 19.46 vs. 3.50 ± 5.96], obstructive [34.86 ± 44.37 vs. 9.71 ± 10.48], and mean apnea-hypopnea index [AHI] [16.91 ± 18.0 vs. 7.86 ± 7.84]). Acromegalics had significantly higher prevalence of obstructive SA (71.4% [mild 31.4%, moderate 20%, severe 20%]) as compared to controls (38.2%). There was no correlation of AHI with serum IGF-1 and disease duration.

Conclusion:

Acromegaly subjects have a significantly higher prevalence of respiratory symptoms, SA, and abnormalities in PFT. Screening for respiratory comorbidities should be routinely recommended in all patients with acromegaly.

Prevalence and outcome of comorbidities associated with acromegaly

BACKGROUND

Acromegaly is associated with various comorbidities, such as arterial hypertension (aHT), type 2 diabetes mellitus (DM2), obstructive sleep apnoea syndrome (OSAS), carpal tunnel syndrome (CTS) and polyposis coli. For therapeutic decisions, it is essential to know if, and to what extent, these associated morbidities are reversible or preventable. The aim of this study is to assess the prevalence and course of aHT, obesity, OSAS, CTS, DM2 and polyposis coli in acromegalic patients.

METHODS

The following criteria for inclusion in this database study were used: treatment for acromegaly at the authors' institutions; full endocrinological and radiological work- and follow-up; screening for aHT, DM2, CTS, OSAS, obesity and polyposis coli. All patients were followed-up for > 3 months, and treatments were indicated with the intent of biochemical remission (normal IGF-1 and random growth hormone level).

RESULTS

Sixty-three patients were included. Twelve (19%), 45 (71%) and 6 (10%) patients harboured micro-, macro- and giant adenomas, respectively. Nineteen tumours (30%) invaded the cavernous sinus. Mean tumour volume was 5.4 cm³. Mean follow-up time was 42 months. Sixty-one (97%) patients had transsphenoidal surgery; two patients only had drug therapy. Surgery led to remission in 31 (51%) patients. Intracavernous growth and larger tumour volume were negative predictors for cure. Drug therapy lead to remission in 22 (73%) patients within a mean follow-up of 54 months. The pretherapeutic prevalence of associated morbidities was as follows: aHT, 56%; DM2, 25%; OSAS, 29%; CTS, 29%; polyposis coli, 5%. There were neither age nor gender preferences for the respective prevalences. Surgery leads to remission of aHT and DM2 in 6% and 25%, respectively. Additional drug therapy resulted in remission of aHT, DM2 and CTS in 17%, 14% and 14%, respectively. Other associated morbidities persisted regardless of therapeutic efforts. Even if criteria for remission were not met, no new comorbidities of acromegaly developed during follow-up.

CONCLUSIONS

Treating acromegaly may relieve threatening associated morbidities such as aHT and DM2; nevertheless, only few comorbidities are reversible, which highlights the importance of treating acromegaly as early as possible.

Densely granulated adenoma pattern is associated with an increased risk of obstructive sleep apnea in patients with acromegaly

OBJECTIVES

To explore the prevalence of obstructive sleep apnea (OSA) and the association between the adenoma granulation patterns and OSA in patients with acromegaly.

METHODS

An overnight polysomnography (PSG) assessment was carried out on participants with acromegaly. Results classified participants into a non-OSA group, mild to moderate OSA group, and severe OSA group. Morphological and biochemical analyses were performed. Demographic, clinical, biochemical, and polysomnographic data were compared among the three groups. Using logistic regression models, the risk of OSA in acromegalic subjects was estimated.

RESULTS

OSA was reported in 36 of 49 patients (74%) with acromegaly. Contrasted with the non-OSA group, OSA patients had a larger proportion of the densely granulated (DG) pattern. The OSA groups with DG acromegaly had a smaller maximum tumor diameter and Vol/2 than those with the sparsely granulated (SG) pattern. Furthermore, a higher growth hormone (GH) level (45.0 ± 36.9 vs 18.6 ± 15.8, P = 0.047) and GH index (28.4 ± 13.8 vs 6.6 ± 8.2, P = 0.003) were found in DG acromegaly patients with severe OSA. Additionally, there was a trend toward higher standardized insulin-like growth factor 1 (IGF-1) in patients with DG acromegaly than in those with SG acromegaly in the severe OSA group. After adjusting for potential confounding variables, the DG pattern was correlated with the risk of OSA (OR = 14.84, 95%CI 1.36-162.20, P = 0.027) in patients with acromegaly.

CONCLUSIONS

The findings indicate that a high prevalence of OSA exists in patients with acromegaly, and the DG pattern may be a risk factor for OSA in acromegaly.

[Heart arrhythmias and conduction disorders in patients with acromegaly: the role of cardiac magnetic resonance imaging]

Cardiovascular complications including arrhythmias and cardiac conduction disorders are one of the main reasons of high mortality rate in acromegaly, while they have not been well explored.

AIM

To estimate arrhythmias frequency in acromegaly, identify risk factors leading to the development of arrhythmia and cardiac conduction disorder, to determine the role of cardiac MRI in detecting structural and functional changes.

MATERIALS AND METHODS

A single-center prospective cohort study, which included 461 patients (151 men and 310 women) with acromegaly, was conducted. All the patients underwent a standard medical examination, including hormonal blood test, electrocardiogram, echocardiography, electrocardiogram daily monitoring. 18 patients with arrhythmias (11 men and 7 women) had cardiac MRI with gadolinium-based contrast.

RESULTS

The results of our research show high frequency of arrhythmias and cardiac conduction disorders in patients with acromegaly 42%. Most frequent kinds of arrhythmias and cardiac conduction disorders were sinus bradycardia 19.1% of the cases and conduction disorders of bundle branch blocks 14.5%. Men were more likely to suffer from arrhythmias and cardiac conduction disorders than women (54.2% and 37.4%, respectively,p=0.0005). Not acromegaly activity but duration of the disease was a main risk factor of arrhythmias and cardiac conduction disorders. Patients with arrhythmias had a long anamnesis of acromegaly (10 and 7 years, respectively, p=0.04). Meanwhile, cardiac conduction disorders were commonly observed in the patients who were treated with somatostatin analogs comparing to the patients who didnt undergo this therapy (50% and 38.6% respectively,p=0.004). We showed that 61% of patients with acromegaly and cardiac conduction disorders who underwent magnetic resonance imaging (MRI) had the signs of myocardial fibrosis. The value of the ejection fraction of the left ventricle according to MRI was higher than with echocardiography (p=0.04).

CONCLUSION

Arrhythmias and cardiac conduction disorders are often observed in patients with acromegaly even with remission of the disease. High risk group need careful diagnostic and monitoring approaches. Cardiac MRI is the gold standard for visualization of structural and morphological changes in the heart. Use of cardiac MRI in acromegalic patients expands our understanding of arrhythmias and cardiac conduction disorders in this disease. There are no specific laboratory markers of diffuse myocardial fibrosis, and the role of myocardial fibrosis in the occurrence of cardiac arrhythmias and conduction disorders needs further studying.

Updates in rare and not-so-rare complications of acromegaly: focus on respiratory function and quality of life in acromegaly

Acromegaly is a complex disease with excessive growth hormone and insulin-like growth factor 1 (IGF-1) causing multisystem effects, particularly cardiovascular, respiratory, and metabolic. Psychological concerns and poor quality of life (QoL) are also major disease consequences. This review is intended for clinicians and focuses on the latest developments related to respiratory and QoL effects of long-term growth hormone excess. Along with biochemical disease control, patient treatment satisfaction and outcomes have become major treatment objectives; current knowledge and tools to evaluate and manage this aspect of the disease are described. Sleep apnea syndrome and other derangements of lung function and apparatus, from pathophysiology to treatment, and evaluation tools and determinants of QoL in patients with acromegaly are discussed.

Acromegaly in the elderly patients

BACKGROUND

Acromegaly is a rare disease characterized by a chronic exposition to growth hormone (GH) and insulin-like growth factor-1 (IGF-1), caused in most cases by a pituitary GH-secreting adenoma. Chronic GH excess induces systemic complications (metabolic, cardiovascular, respiratory, neoplastic, and musculoskeletal) and increased mortality if not appropriately treated. Recent epidemiological data report an improved life span of patients with acromegaly probably due to better acromegaly management; additionally, the number of pituitary incidentaloma in general population also increased over time due to more frequent imaging. Therefore, the number of elderly patients, newly diagnosed with acromegaly or in follow-up, is expected to grow in the coming years and clinicians will need to be aware of particularities in managing these patients.

PURPOSE

This review aims to explore different aspects of acromegaly of the elderly patients, focusing on epidemiology, diagnosis, clinical presentation, complications, and management options.

METHODS

Available literature has been assessed through PubMed (data until August 2019) by specific keywords.

CONCLUSIONS

Available data on acromegaly in the elderly patient are sparse, but point to important differences. Further studies are needed comparing elderly with younger patients with acromegaly to better define a tailored diagnostic and therapeutic management.

The Course of Obstructive Sleep Apnea Syndrome in Patients With Acromegaly During Treatment

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 < 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.

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.

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 posterior pharyngeal wall thickness is associated with OSAHS in patients with acromegaly and correlates with IGF-1 levels

PURPOSE

To evaluate the incidence of obstructive sleep apnea-hypopnea syndrome (OSAHS), explore the structural changes in pharyngeal soft tissue underlying OSAHS development and analyze the correlation between hormone levels and pharyngeal soft tissue changes in patients with untreated acromegaly.

METHODS

Twenty-five patients with untreated acromegaly were prospectively enrolled. Pituitary hormones were tested, sellar magnetic resonance imaging was confirmed, overnight polysomnography was conducted, and upper airway computed tomography was performed on these patients.

RESULTS

Patients with untreated acromegaly had a high incidence of OSAHS (52.0%, 13/25). The average age of the patients with OSAHS was 12 years older than that of patients without OSAHS (47.0 ± 8.5 years vs. 35.1 ± 9.5 years, p = 0.003). The posterior pharyngeal soft tissues were thicker in four different planes, including the planes of the soft palate, uvula, tongue and epiglottis (p = 0.003, 0.008, 0.027, and 0.003, respectively), and the soft palate (p = 0.024) was more hypertrophic in patients with acromegaly presenting with OSAHS than patients without OSAHS. The posterior pharyngeal wall thickness (cm) positively correlated with the serum insulin-like growth factor 1 (IGF-1) level (ng/ml) in the planes of the soft palate (slope = 0.001, p = 0.006) and epiglottis (slope = 0.002, p = 0.039).

CONCLUSIONS

OSAHS is a common complication in patients with untreated acromegaly, and advanced age is a risk factor. Posterior pharyngeal soft tissue thickening and soft palate hypertrophy are structural changes underlying OSAHS development in patients with acromegaly. Higher IGF-1 levels predict an increase in the posterior pharyngeal soft tissue thickness in patients with acromegaly.

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.

Increased Risk of Persistent Glucose Disorders After Control of Acromegaly

Purpose:

Combining surgery and medical treatments allows the control of growth hormone hypersecretion in 80% of cases. Our objective was to determine the rate of acromegaly comorbidities once hypersecretion of growth hormone is controlled.

Methods:

Our retrospective monocentric study was based on 130 patients followed on a regular basis, with acromegaly controlled by medical treatments or cured by surgery or radiation technique. Our main outcome measures were the prevalence of major metabolic complications of acromegaly (diabetes, hypertension, low-density lipoprotein cholesterol, triglycerides) at diagnosis and last follow-up in comparison with French epidemiological data.

Results:

As expected, controlling hypersecretion significantly improved the metabolic complications of acromegaly. However, the proportion of patients having at least one metabolic complication of acromegaly at last follow-up (mean, 72 months after remission) was 27% for altered glucose tolerance or diabetes, 39% for hypertension, 34.3% for hypercholesterolemia, and 13.3% for hypertriglyceridemia. Interestingly, our data showed that diabetes was the only comorbidity different with a higher prevalence in patients in remission versus a general population of a similar median age (21.6% vs 6.9%, respectively).

Conclusions:

The follow-up of glucose disorders needs to be maintained on a long-term basis in patients controlled for acromegaly.

Airway and sleep disorders in patients with acromegaly

OBJECTIVE

Acromegaly is a multisystemic disorder caused by excessive secretion of growth hormone (GH). Sleep-disordered breathing (SDB) such as sleep apnea syndrome (SAS) may occur in acromegaly. The aim of study was to assess the presence of sleep disorders and evaluate the systemic complications on respiratory, cardiovascular, and upper airway systems in acromegalic patients.

METHODS

The study group consisted of 30 acromegaly outpatients. GH and insulin-like growth factor 1 (IGF-1) measurements were obtained; body pletysmography, arterial blood gas analysis, tissue-doppler imaging, echocardiography, polysomnography, otorhinolaryngologic examination, and head-neck computed tomography were performed.

RESULTS

Sixteen female (53.3%) and 14 male (46.7%) acromegalic patients had a mean age of 51.1 ± 13.2. GH was supressed in 19 patients (63.3%) when 11 had active acromegaly (36.7%). There were 17 patients with SAS (62.9%) (7: mild, 3:intermediate, 7:severe SAS) and average AHI was 16/h. Sixteen patients had predominantly obstructive SAS while one patient had predominantly central SAS. SAS was statistically more frequent in males than females (P = .015). The mean neck circumference was significantly longer in patients with SAS (P = .048). In SAS patients,the soft palate was elongated and thickened,which was statistically significant (P = .014 and P = .05).Vallecula-to-tongue distance was statistically longer in acromegalic patients with SAS (P = .007).There was a positive correlation between tonsil size,vallecula-to-tongue distance and AHI (r = 0.432, P = .045 and r = 0.512, P = .021, respectively).

CONCLUSION

SDB seems to be common and clinically important in patients with acromegaly, particularly in men. The most frequent type of apnea in acromegalics is obstructive. Hormonal activity of acromegaly does not seem to have an effect on the development of SAS. Despite its high prevalence, SAS is frequently under-assessed in patients with acromegaly. Systemic complications and SDB should be researched in acromegalics.

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.

Pituitary diseases and sleep disorders

PURPOSE OF REVIEW

Patients with pituitary diseases have decreased quality of life. Sleep disorders are prevalent among patients with pituitary diseases and contribute to decreased quality of life.

RECENT FINDINGS

Patients previously treated for compression of the optic chiasm by surgery, and in some cases postoperative radiotherapy, suffer from sleep disorders. These are characterized by decreased sleep quality, delayed onset of sleep, and daytime sleepiness. Circumstantial evidence suggests that this may be caused by hypothalamic dysfunction. A challenging speculation is that previous compression of the optic chiasm compromised the function of the retinohypothalamic tract. Through this tract the eyes convey information on day-night cycles to the hypothalamic nuclei. Patients with acromegaly, even despite biochemical control, suffer frequently from obstructive sleep apnea. Patients with Cushing's disease suffer from fragmented sleep, sleep apnea, and snoring. Prolactinomas do not seem to affect sleep characteristics. The association between appropriately substituted pituitary insufficiency and sleep disorders is less clear. The effects of recombinant human growth hormone on sleep characteristics in adults are inconsistent.

SUMMARY

Pituitary disorders are associated with different sleep disorders. Different studies point to irreversible changes in sleep-wake rhythmicity in patients treated previously for pituitary tumors with chiasm compression. VIDEO ABSTRACT.

Morphological study of upper airways and long-term follow-up of obstructive sleep apnea syndrome in acromegalic patients

Pathogenesis and long-term outcome of obstructive sleep apnea syndrome (OSAS) in acromegalic patients are still under debate. The aim of the study was to assess the prevalence and long-term follow-up of a series of acromegalic patients with OSAS and to investigate site, degree, and possible causes of upper airway obstruction by morphological study. Cross-sectional and longitudinal study was conducted in 58 acromegalic patients (33 active, 25 controlled) with polysomnography in all subjects, repeated in 25 patients with OSAS, and echocardiography. Morphological study including fiberoptic nasopharyngoscopy with the Müller maneuver (FNMM), magnetic resonance imaging (MRI), with 3-dimensional (3D) elaboration was also performed. The prevalence of OSAS was 58.6 % in the whole series: 63.6 % in the active group and 52 % in the controlled one. Left ventricular hypertrophy was more prevalent in patients with OSAS. OSAS improved in 62.5 % of active patients after achieving hormonal control, whereas it persisted or got worse in 66.6 % of the controlled ones. The uvula and tongue base were the main site of obstruction assessed by FNMM. Uvula diameters obtained by MRI study correlated with the severity of upper airway collapse assessed by FNMM and tongue measure with apnea-hypopnea index (p = 0.044). A greater narrowing and a smaller total volume of upper airways were confirmed by 3D-MRI in patients with more severe OSAS. Uvula and tongue hypertrophy plays a relevant role in the pathogenesis and severity of OSAS. Intensive treatment of acromegaly needs to be promptly adopted in order to reverse it.

Functional changes are associated with tracheal structural abnormalities in patients with acromegaly

INTRODUCTION

Although impaired pulmonary function and respiratory sleep disorders are described as responsible for increased mortality in acromegalic patients, little is known about the tracheal abnormalities in this group of patients. Thus, the objectives of this study were to describe the tracheal structural abnormalities and correlate these changes with the respiratory function and clinical data of acromegalic patients.

MATERIAL AND METHODS

This is a cross-sectional study that was carried out at two university hospitals. Twenty acromegalic patients underwent spirometry, forced oscillation technique, and computed tomography (CT) assessments. Dyspnea and daytime sleepiness were assessed using the Modified Medical Research Council (MMRC) scale and the Epworth Sleepiness Scale (ESS), respectively. Forty matched subjects served as controls.

RESULTS

The acromegalic patients exhibited larger median ratios between forced expiratory flow and forced inspiratory flow at 50% of the forced vital capacity (FEF50%/FIF50%) (2.05 vs. 1.06, p = 0.0001) compared with healthy volunteers. In the CT analysis, acromegalic patients exhibited larger median differences between their cervical and thoracic tracheal diameters (Δ tracheal diameters) (3 vs. 1 mm; p = 0.003). An association was found between FEF50%/FIF50% and the following variables: mean resistance (Rm), cervical tracheal diameter, and Δ tracheal diameters. Rm also exhibited a negative correlation with cervical tracheal diameter. Neither the MMRC scale nor the ESS exhibited any significant correlation with large airway obstruction (LAO) indices or with the measured tracheal diameters.

CONCLUSIONS

Acromegalic patients have tracheal structural abnormalities which are associated with functional indicators of LAO but not with clinical data.

Cardiovascular Disease and Sleep-Disordered Breathing in Acromegaly

Treatment goals in acromegaly include symptom relief, tumour control and reversal of the excess morbidity and mortality associated with the disorder. Cardiovascular complications include concentric biventricular hypertrophy and cardiomyopathy, hypertension, valvular heart disease and arrhythmias, while metabolic disturbance (insulin resistance/diabetes mellitus, dyslipidaemia) further increases the risk of cardiovascular and cerebrovascular events. Sleep-disordered breathing (in the form of sleep apnoea) is also common in patients with acromegaly and may exacerbate cardiovascular dysfunction, in addition to contributing to impaired quality of life. Accordingly, and in keeping with evidence that cardiorespiratory complications in acromegaly are not automatically reversed/ameliorated simply through the attainment of 'safe' growth hormone and insulin-like growth factor 1 levels, recent guidelines have emphasised the need not only to achieve stringent biochemical control, but also to identify and independently treat these comorbidities. It is important, therefore, that patients with acromegaly are systematically screened at diagnosis, and periodically thereafter, for the common cardiovascular and respiratory manifestations and that biochemical targets do not become the only treatment goal.

The beneficial effect of acromegaly control on blood pressure values in normotensive patients

OBJECTIVE

Control of acromegaly may ameliorate blood pressure (BP) in hypertensive (HT) patients. We evaluated the impact of acromegaly control on BP values of normotensive (NT) acromegalics.

DESIGN

Retrospective cohort study.

PATIENTS

Fifty-eight naïve patients with acromegaly (39 F; age range, 30-69 years), including 28 NT and 30 HT subjects, participated in the study.

MEASUREMENTS

Blood pressure was measured by clinical measurement and 24-h ambulatory monitoring at diagnosis and after 24 months of medical therapy for acromegaly.

RESULTS

Acromegaly was controlled by medical therapy in 15 NT and 17 HT patients at 24 months. In the NT group, systolic (SBP) or diastolic (DBP) BP significantly increased (all P < 0·005) when acromegaly was uncontrolled, but did not change when the disease was controlled. Changes in SBP and DBP were also significantly different between uncontrolled and controlled NT patients. At 24 months, clinical hypertension was detected only in uncontrolled NT patients (46% vs 0%, P < 0·001), whereas ambulatory hypertension was found in 38% of uncontrolled and in 7% of controlled NT subjects (P = 0·035). In the HT group, ambulatory SBP increased in patients with uncontrolled acromegaly (24-h SBP P = 0·046, day SBP P = 0·005, night SBP P = 0·005), whereas ambulatory DBP decreased in subjects with controlled disease (24-h DBP P = 0·008, day DBP P = 0·026).

CONCLUSIONS

Control of acromegaly has a beneficial effect on BP regulation either in HT or NT subjects; in the latter, it may prevent progression towards hypertension.

Impact of successful treatment of acromegaly on overnight heart rate variability and sleep apnea

BACKGROUND

Successful treatment of acromegaly improves disease-related cardiovascular mortality and morbidity, but its effects on autonomic modulation of the heart rate are unknown.

OBJECTIVES

We documented treatment-induced changes in time-domain heart rate variability, taking into account the confounding effects of obstructive sleep apnea.

PATIENTS AND METHODS

Sixteen consecutive patients (12 males, aged 43 ± 12 y) with newly diagnosed acromegaly underwent overnight (12:00-7:00 am) cardiac Holter recordings coupled with polysomnography. Data were obtained before and 10 ± 6 months after successful treatment of acromegaly.

RESULTS

IGF-1 levels fell from 807 ± 333 to 207 ± 69 μg/L and normalized in all patients. Seven patients (44%) had obstructive sleep apnea (apnea-hypopnea index 33 ± 21/h) at baseline. Treatment had no significant effect on polysomnographic indices. After treatment, increases were noted in the normal-to-normal heart period (NN), SD-NN, the percentage of NN differing from the previous NN by greater than 50 msec, and the root mean square of successive differences in NN (each P < .05). These heart rate variability results were not influenced by the type of treatment, and there was no relationship between changes in NN and changes in the apnea-hypopnea index (P = .58).

CONCLUSION

Early after successful treatment of acromegaly, we observed increased parasympathetic modulation/decreased sympathetic modulation of the nighttime heart rate, an effect that seems unrelated to changes in sleep apnea status. Treatments aimed at normalizing IGF-1 may improve cardiovascular homeostasis through improved cardiac autonomic nervous system modulation.

Octreotide for acromegaly treatment: a reappraisal

INTRODUCTION

Acromegaly is a rare disorder characterized by excess secretion of growth hormone (GH) generally caused by a pituitary macroadenoma and associated with reduced life expectancy if the disease is untreated. This article covers the recent available evidences published on octreotide , the first somatostatin analog introduced into clinical practice for the medical treatment of acromegaly.

AREAS COVERED

This article discusses i) pharmacology of somatostatin and octreotide; ii) biochemical effects of regular octreotide and long-acting repeatable formulation; iii) tumor shrinkage effects of octreotide in acromegaly; iv) impact of octreotide on acromegalic clinical manifestations and chronic complications; v) safety of octreotide and vi) place of octreotide in the guidelines for acromegaly treatment. Full-text articles in the English language were selected from a PubMed search spanning 1984 - 2013, for keywords including 'octreotide,' 'acromegaly,' 'GH,' 'IGF-I,' and 'tumor shrinkage.' Reference lists in selected papers were also used to broaden the search.

EXPERT OPINION

Octreotide is a mature drug with a consolidated favorable benefit versus risks profile in the treatment of acromegaly.

[Characteristics of sleep apnea syndrome in a cohort of patients with acromegaly]

INTRODUCTION

Sleep apnoea syndrome (SAS) has a prevalence of between 40 and 80 % in patients with acromegaly. The objective of our study was to focus on the occurrence of SAS and its relation with acromegalic characteristics in this population as well as to study patients' comorbidities.

METHODOLOGY

This study was retrospective, monocentric and related to a cohort of 106 acromegalic patients of whom 55 patients had performed ventilatory polygraphic recordings looking for SAS in addition to assessment of comorbidities.

RESULTS

Within the screened patients, 42 had sleep apnoea syndrome with a majority of them having severe SAS. In this population, SAS was associated with hypertension, diabetes and a longer duration of acromegaly but acromegaly control was not a risk factor. Patients with severe SAS were older (mean 64 years) than the ones without SAS (47 years) (P=0.01).

CONCLUSION

SAS prevalence is twenty times higher in the acromegalic population than for the normal population, even more so if patients are diabetic, hypertensive, older and if acromegaly has had a long evolution. Knowing this high prevalence, systematic screening for SAS may be justified in this population.

Characteristics of sleep-disordered breathing in Japanese patients with acromegaly

Sleep-disordered breathing (SDB), especially sleep apnea-hypopnea syndrome (SAS), is often observed in patients with active acromegaly. This complication is a risk factor for cardiovascular disease and associated with increased morbidity and mortality in acromegaly. However there is little information on SDB in Japanese patients with acromegaly. We investigated the prevalence of SDB and association between the severity of SDB and various features and biomarkers in Japanese patients with acromegaly. Twenty-four Japanese patients with active acromegaly underwent overnight cardiorespiratory monitoring, hormonal assays and cephalometric measurements on X-ray. A high prevalence of SDB was detected in acromegaly (87.5%). Log apnea-hypopnea index (AHI) correlated positively with soft palate length / body height (X-ray) (r=0.44, p=0.043), but not with log growth hormone levels and insulin-like growth factor type-1 standard deviation scores, size of pituitary adenoma, disease duration, body mass index, waist circumference, estimated visceral fat area, heel pad thickness / height, tongue thickness/ height, or oropharyngeal dimension/ height. In conclusion, our study demonstrated a high prevalence of SDB in Japanese patients with acromegaly, and its severity correlated with soft palate length. Based on the high incidence of SDB identified in the present study, we recommend that all patients with acromegaly are routinely screened for SDB for early diagnosis and treatment.

Sleep apnea in acromegaly: a review on prevalence, pathogenetic aspects and treatment

Sleep apnea syndrome is a common complication of acromegaly with a negative impact on quality of life and survival. Obstructive sleep apnea is the prevailing form and is characterized by recurrent episodes of apnea and hypopnea owing to the total or partial collapse of the upper airways during sleep. The craniofacial deformations and the hypertrophy of upper airway soft tissue are responsible for its occurrence. Successful treatment of acromegaly can improve the severity of this complication, but can only seldom reverse it, particularly after a long time of active acromegaly. Thus, it is advisable to evaluate patients for sleep apnea syndrome at diagnosis and during treatment, and also when acromegaly is biochemically controlled. In selected cases, continuous positive airway pressure should be implemented to improve patient outcome.

Assessment of the awareness and management of sleep apnea syndrome in acromegaly. The COM.E.TA (Comorbidities Evaluation and Treatment in Acromegaly) Italian Study Group

In 2007 the Italian COM.E.T.A. (COMorbidities Evaluation and Treatment in Acromegaly) study group started to assess the application in a clinical setting of the Versailles criteria for management of acromegaly complications by a first questionnaire focusing on cardiovascular co-morbidities. A further questionnaire on sleep apnea syndrome (SAS) was delivered by the COM.E.T.A. study group to 107 endocrine centers in Italy. The results of our survey suggest that SAS is a well-known comorbidity even if its estimated prevalence is lower than in the literature. Polysomnography is the preferred tool for diagnosis. Control of SAS is considered relevant both for quality of life and co-morbidities. Continuous positive airway pressure is the cornerstone of therapy, but patients' acceptance may be critical. Control of GH/IGF-I secretion is important to improve SAS. Management of SAS requires cooperation between specialists.

Endocrine aspects of obstructive sleep apnea

CONTEXT

Some endocrine and metabolic disorders are associated with a high frequency of obstructive sleep apnea (OSA), and treatment of the underlying endocrine disorder can improve and occasionally cure OSA. On the other hand, epidemiological and interventional studies suggest that OSA increases the cardiovascular risk, and a link between OSA and glucose metabolism has been suggested, via reduced sleep duration and/or quality.

EVIDENCE ACQUISITION

We reviewed the medical literature for key articles through June 2009.

EVIDENCE SYNTHESIS

Some endocrine and metabolic conditions (obesity, acromegaly, hypothyroidism, polycystic ovary disease, etc.) can be associated with OSA. The pathophysiological mechanisms of OSA in these cases are reviewed. In rare instances, OSA may be improved or even cured by treatment of underlying endocrine disorders: this is the case of hypothyroidism and acromegaly, situations in which OSA is mainly related to upper airways narrowing due to reversible thickening of the pharyngeal walls. However, when irreversible skeletal defects and/or obesity are present, OSA may persist despite treatment of endocrine disorders and may thus require complementary therapy. This is also frequently the case in patients with obesity, even after substantial weight reduction.

CONCLUSIONS

Given the potential neurocognitive consequences and increased cardiovascular risk associated with OSA, specific therapy such as continuous positive airway pressure is recommended if OSA persists despite effective treatment of its potential endocrine and metabolic causes. "Apropos of sleep, that sinister adventure of all our nights, we might say that men go to bed daily with an audacity that would be incomprehensible if we did not know that it is the result of ignorance of the danger." Charles Baudelaire, in "Fusées, IX"

GH and IGF-I excess control contributes to blood pressure control: results of an observational, retrospective, multicentre study in 105 hypertensive acromegalic patients on hypertensive treatment

CONTEXT

Approximately one-third of patients with acromegaly have concomitant hypertension. The outcome of hypertension after treatment of acromegaly is unknown.

OBJECTIVE

To evaluate the role of GH and IGF-I control on systolic (SBP) and diastolic blood pressure (DBP) levels.

PATIENTS

One hundred and five hypertensive patients (60 women, 45 men) with active disease receiving treatment for hypertension at their diagnosis of acromegaly.

DESIGN

Observational, retrospective, multicentre.

MEASUREMENTS

At diagnosis and after 24 months (median) of treatment we measured serum GH and IGF-I levels, blood pressure levels, left ventricular (LV) mass index (LVMi), early-to-late mitral flow velocity (E/A, as a measure of diastolic function) and LV ejection fraction (LVEF, as a measure of systolic function).

RESULTS

At the diagnosis of acromegaly, hypertension was mild in 41.1% and severe in 58.9%. Serum GH and IGF-I levels did not differ in patients with mild or severe hypertension. After 24 months of treatment, all patients had a notable decrease in both GH and IGF-I levels, and achieved significantly lower levels of DBP, heart rate and LVMi; 76 patients (71%) had achieved control of GH and IGF-I levels. Only the patients with controlled acromegaly achieved significantly lower SBP levels and significantly improved cardiac systolic and diastolic function. A higher dose of antihypertensive drugs and/or an increased number of drugs to control hypertension were significantly greater in patients with uncontrolled (32.3%) than in those with controlled acromegaly (7.8%; P = 0.004).

CONCLUSION

Hypertensive patients with controlled acromegaly achieved improved control of hypertension and of cardiac diastolic and systolic function. The use of antihypertensive drugs was significantly less in patients achieving control of acromegaly.

Airway Management in Patients With Pituitary Disease

Difficulties in airway management are observed among patients with pituitary disease. The purpose of this study was to better characterize the relationship between disease factors such as tumor characteristics on difficult endotracheal intubation. The perioperative records of 746 patients that underwent transsphenoidal microsurgery at the University of Virginia between January 1995 and June 2001 were reviewed. Among the 746 patients studied, difficulty with endotracheal intubation was encountered in 28 patients (3.8%). Patient gender and tumor size were not associated with a difference in the incidence of unanticipated airway management difficulty. Unanticipated difficulty with airway management was more than three times more common in acromegalic patients (n = 121) than in patients with nonfunctioning pituitary tumors (9.1% [5.8-14%] vs 2.6% [1.5-4.5%], P = 0.007). Patients with Cushing disease (n = 182) and patients with a prolactinoma (n = 87) were no more difficult to intubate than patients with nonfunctioning tumors. Among patients with acromegaly, neither tumor size nor patient gender has any impact on the incidence of intubation difficulty. Among all patients, when difficulty was encountered, intubation assisted by the gum elastic bougie was successful 100% of the time. The incidence of difficulty in intubation is not higher among patients with pituitary disease than in the general surgical population; however, patients with acromegaly have difficult intubations three times more often.

Hypertension in acromegaly and in the normal population: prevalence and determinants

BACKGROUND

The GH/IGF-I axis has a relevant role to play in the cardiovascular system but its implication in the pathogenesis of hypertension in the normal population and in acromegaly is not yet clear.

PATIENTS AND MEASUREMENTS

The aim of this retrospective and controlled study was to evaluate the prevalence and determinants of hypertension in 200 patients with acromegaly and 200 nonacromegalic subjects, matched for sex, age, body mass index (BMI) and smoking habits.

RESULTS

Hypertension was found in 46% of patients and in 25% of controls (P < 0.0001), without any difference between men and women. Family history of hypertension occurred in 30% of hypertensive acromegalic patients and in 62% of hypertensive controls (P < 0.0001). In both groups, hypertensive subjects were older than normotensive subjects. Systolic (SBP) and diastolic blood pressures (DBP) in hypertensive acromegalic patients were lower and higher, respectively, than in hypertensive controls. The risk of hypertension increased with age and was higher in the patients than in the controls [hazard ratio (HR) 1.9; P = 0.0002]. Independent predictors of SBP were age and glucose in the acromegalic population, and BMI, age and glucose levels in the controls. Independent predictors of DBP were age and glucose in the patients, and BMI, age and IGF-I in the controls.

CONCLUSIONS

In acromegaly, hypertension is more frequent than in the general population, involves predominantly DBP, and occurs earlier, is not related to gender, and is less frequently related to family history of hypertension and IGF-I levels. IGF-I may have a protective role for DBP in the general population.

Sleep apnoea in the older adult : pathophysiology, epidemiology, consequences and management

Sleep apnoea is a breathing disorder in sleep usually caused by repetitive upper airway obstruction. Its primary symptoms include snoring, daytime sleepiness and decreased cognitive functioning. Risk factors for the condition include obesity, anatomical abnormalities, aging, and family history. It has been associated with hypertension, cardiovascular and pulmonary diseases and increased mortality. The prevalence of sleep apnoea increases with age, although the severity of the disorder, as well as the morbidity and mortality associated with it, may actually decrease in the elderly. A decline in cognitive functioning in older adults with sleep apnoea may resemble dementia. Medical management of sleep apnoea rarely relies on drug treatment, as the few drugs (antidepressants and respiratory stimulants) tested for treatment have been found to be ineffective, or cause tolerance or serious adverse effects and complications. The treatment of choice for sleep apnoea is continuous positive airway pressure, a device which generates positive air pressure through a nose mask, creating a splint which keeps the airway unobstructed throughout the night. Weight loss significantly decreases or eliminates apnoeas. Oral appliances are used to enlarge the airway at night by moving the tongue and mandible forward. Positional therapy involves avoiding the supine position during sleep in patients who mostly have apnoeas while lying on their back. Surgical management may also be considered, although with great caution in the elderly, because of their increased risk of complications related to surgery. Surgical procedures include nasal reconstruction, somnoplasty, laser-assisted uvuloplasty, uvulopalatopharyngoplasty, genioglossus advancement and hyoid myotomy, and maxillomandibular advancement for severe cases when other treatments have failed. As a last option, tracheostomy may be performed.

Systemic complications of acromegaly: epidemiology, pathogenesis, and management

This review focuses on the systemic complications of acromegaly. Mortality in this disease is increased mostly because of cardiovascular and respiratory diseases, although currently neoplastic complications have been questioned as a relevant cause of increased risk of death. Biventricular hypertrophy, occurring independently of hypertension and metabolic complications, is the most frequent cardiac complication. Diastolic and systolic dysfunction develops along with disease duration; and other cardiac disorders, such as arrhythmias, valve disease, hypertension, atherosclerosis, and endothelial dysfunction, are also common in acromegaly. Control of acromegaly by surgery or pharmacotherapy, especially somatostatin analogs, improves cardiovascular morbidity. Respiratory disorders, sleep apnea, and ventilatory dysfunction are also important contributors in increasing mortality and are advantageously benefitted by controlling GH and IGF-I hypersecretion. An increased risk of colonic polyps, which more frequently recur in patients not controlled after treatment, has been reported by several independent investigations, although malignancies in other organs have also been described, but less convincingly than at the gastrointestinal level. Finally, the most important cause of morbidity and functional disability of the disease is arthropathy, which can be reversed at an initial stage, but not if the disease is left untreated for several years.

Diagnosis and management of pituitary tumors: recent advances

In recent years, the medical therapy for prolactinomas and GH-secreting adenomas has greatly improved due to the availability of new, highly effective, long-acting dopamine and somatostatin analogues. Although medical therapy has for some time been the first-line approach to prolactinoma management, the incidence of patients requiring surgery for resistance or intolerance/noncompliance is likely to decrease substantially with these new agents. Increasing efficacy and greater ease of administration of somatostatin analogues for GH, and for rare TSH, adenomas are also anticipated to lead to less reliance on surgery and radiation therapy as the primary therapy in these disorders. Although somewhat unclear at this time, GH antagonists hold promise for alternative or adjunct therapy for acromegaly. Given the significant morbidity and mortality associated with acromegaly, these advances are quite encouraging. Unfortunately, little if any progress has been made toward establishing an effective medical treatment for gonadotropin or nonsecreting tumors. However, new approaches to delivery of radiation therapy may reduce some of the inconvenience and risk of this treatment for patients when surgery alone is inadequate. In all of these disorders, the challenge to physicians and their patients remains one of choosing a rational combination of medical, surgical, and radiation therapy. Fortunately, for most patients, control, if not cure, of their pituitary adenoma is a reasonable expectation.

Long-term treatment outcome in acromegaly

A number of groups have developed guidelines to indicate whether an individual with acromegaly has been cured by treatment. However, studies to date do not provide a robust definition of biochemical remission of the disorder based on correlation with long-term outcome. Available data suggest that those with a random serum growth hormone (GH) level of <2.5 microg/l, or a glucose-suppressed GH level of <1 microg/l following treatment have mortality figures indistinguishable from the general population. However, the confidence limits for these mortality estimates are quite wide. It remains possible that growth hormone levels lower than 1 microg/l for random samples, or even lower when using ultrasensitive GH assays, may indicate superior outcome, but this remains to be confirmed. There are limited data relating serum insulin-like growth factor-I (IGF-I) levels to outcome, although normalisation of serum IGF-I clearly improves outcome compared with continued elevation of measurements after treatment. Current evidence suggests that a post-treatment random serum GH <2.5 microg/l and a normal serum IGF-I value defines biochemical cure. Available data suggest that achieving similar growth hormone levels after treatment also reduces the prevalence of chronic complications of the disorder, which is subsequently reflected in improved mortality.

Hormones and breathing

A number of hormones, including hypothalamic neuropeptides acting as neurotransmitters and neuromodulators in the CNS, are involved in the physiologic regulation of breathing and participate in adjustment of breathing in disease. In addition to central effects, some hormones also control breathing at peripheral chemoreceptors or have local effects on the lungs and airways. Estrogen and progesterone seem to protect from sleep-disordered breathing, whereas testosterone may predispose to it. Progesterone and thyroxine have long been known to stimulate respiration. More recently, several hormones such as corticotropin-releasing hormone and leptin have been suggested to act as respiratory stimulants. Somatostatin, dopamine, and neuropeptide Y have a depressing effect on breathing. Animal models and experimental human studies suggest that also many other hormones may be involved in respiratory control.

Polysomnographic findings in five adult patients with pituitary insufficiency before and after cessation of human growth hormone replacement therapy

OBJECTIVE

We observed the new onset of severe obstructive sleep apnoea syndrome (OSAS) in an adult male patient during human growth hormone (hGH) replacement therapy. This prompted us to evaluate the potential influence of hGH substitution therapy on sleep in middle-aged men.

DESIGN

A longitudinal study.

SUBJECTS

Five male patients (aged 44-56 years, median age 54 years) with postoperative pituitary insufficiency given hGH replacement therapy for 1-2 years (median dose 2.0 U/day; median IGF-I serum concentration 351 microg/l) and 6 months after cessation of hGH treatment (median IGF-I level 77 microg/l - 1 microg/l = 0.131 nmol/l).

MEASUREMENTS

Polysomnographic studies were performed, and the following parameters were determined: time in bed (TIB), sleep period time (SPT), total sleep time (TST), sleep efficiency (SE = TST/TIB), sleep stage 1 onset latency (SL), different sleep stages [W (wake), S1, S2, SWS (slow wave sleep = S3 + S4) and REM; % of SPT], stage shifts per hour of SPT (SS/h), stage shifts to W/h of SPT [A/h (awakening)], index of apnoea and hypopnoea events per hour of TST (AH/h), arousals from apnoea and hypopnoea per hour of TST (Ar/h), index of obstructive (OAH/h), central (CAH/h) and mixed (MAH/h) events of apnoea and hypopnoea per hour of TST and minimal desaturation (MD).

RESULTS

Median baseline results were: TIB, 479 min; SPT, 465 min; TST, 405 min; SE, 77%; SL, 8.5 min; W, 18.9%; S1, 8.2%; S2, 52.7%; REM, 13.5%; SS/h, 17.7; A/h, 2.8; AH/h, 11.9; Ar/h, 4.4; MD, 80%. These parameters did not change significantly after cessation of hGH treatment. In contrast, median SWS decreased significantly from 33 min (7.1%) to 7.5 min (1.8%; P = 0.03). Median OAH/h decreased significantly from 4.4 to 0.1 (P = 0.03) whereas CAH/h increased from 6.3 to 14.6 (P = 0.03) after cessation of hGH. Correspondingly, one patient with OSAS improved markedly whereas another patient developed new and asymptomatic central SAS after cessation of hGH.

CONCLUSION

This study showed that hGH replacement therapy influenced sleep reaction in a complex way in middle-aged men; cessation of treatment was associated with a significant decrease in slow wave sleep and a shift from obstructive to central apnoea and hypopnoea.

Prevalence and pathogenesis of sleep apnea and lung disease in acromegaly

Respiratory disorders are common and important complications in acromegaly. Patients suffering from acromegaly display a 1.6-3.3 fold increase in mortality rate, which is due to respiratory disorders in 25% of cases. In these patients, mortality for lung disease is 2-3 fold higher than in the general population. Every portion of the respiratory system may be involved. Deformities of facial bones, edema and hypertrophy of the mucosae and pharyngeal and laryngeal cartilages, enlargement of the tongue and inspiratory collapse of the hypopharinx, all may contribute to respiratory alterations. Nasal polyps, "hormonal rhinitis", changes of the voice and snoring are common occurrences. Though rarely, a laryngocele may ensue. Pneumomegaly is frequently observed and, as suggested by functional studies, might be due to an increased number rather than volume of the alveoli. An obstructive respiratory syndrome caused by mucosal thickening of the upper airways and bronchi is observed in 25% of female and 70% of male patients. The sleep apnea syndrome (SAS) affects 60-70% of acromegalic patients. SAS may be of obstructive, central or mixed type. Obstructive SAS is the prevailing form in acromegaly. It is due to intermittent obstruction of upper airways with preserved activity of the respiratory center, as testified by the remarkable thoracic and abdominal respiratory efforts. The pathogenesis of the central type of SAS is more complex. Narrowing of the upper airways may induce reflex inhibition of the respiratory center. Moreover, increased GH levels and, possibly, defects in the somatostatinergic pathways, may increase the ventilatory response of the respiratory center to carbon dioxide, thereby leading to respiratory arrest. In the mixed type of SAS, the phenomena underlying the other two forms coexist. Oxygen desaturation concomitant with the apneic episodes accounts for the frequent nocturnal wakening and diurnal drowsiness. Among the clinical correlates of SAS, arterial hypertension is of particular interest due to the close correlation existing between the two disorders. Sleep deprivation related to SAS seems per se to favor the appearance of hypertension. Moreover, short lasting hypoxemia may induce prolonged elevations of blood pressure, mediated by decreased endothelial generation of nitric oxide. Thus, since cardiovascular events are the main cause of mortality in patients with acromegaly, it is reasonable to hypothesize that SAS is involved in the reduced life span of these patients.