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P Marzullo

Publications and source records attributed to P Marzullo.

At least 19 recordsLinked to original sources

Lymphocyte subset pattern in acromegaly.

Immune function in acromegalic patients has been poorly investigated. The aim of this study was to evaluate the main surface antigen clusters of circulating lymphocytes in acromegaly. One hundred patients with active acromegaly (55 women and 45 men, aged 20-70 yr) and 200 healthy subjects sex- and age-matched with the patients (110 women and 90 men, aged 20-70 yr) were enrolled in this study. All patients and controls were born and live in Southern Italy. No patient had received octreotide, bromocriptine or corticosteroids for at least 3 months before entering the study. The analysis of lymphocyte subset pattern was performed by flow cytometry and fluorescein isothiocyanate or phycoerythrin directly conjugated monoclonal antibodies specific for the cell surface antigen clusters (CD) representing T-cell population as a whole (CD3), T helpers (CD4), T suppressors (CD8), natural killer cells (CD16) and B-cell population as a whole (CD19). Acromegalics had significantly increased levels of CD3 (67.1+/-7.2 vs 64.3+/-8.8%; p=0.03) and CD4 (37.8+/-3.5 vs 36.4+/-4.3%; p=0.004) and decreased levels of CD8 (31.4+/-3.3 vs 33.7+/-8.2%; p<0.01) and CD19 (12.1+/-3.1 vs 15.2+/-5.1; p=0.01) without age-difference. The results of the current study demonstrate an increase in T-cell activity together with a decrease in B-cell activity in a very large series of patients with active acromegaly. These data further support the existence of abnormalities of the immune system in patients with chronic GH/IGF-1 excess.

Acromegaly↗

Improvement of left ventricular hypertrophy and arrhythmias after lanreotide-induced GH and IGF-I decrease in acromegaly. A prospective multi-center study.

We report the results of a prospective Italian multi-center study of the effects of lanreotide, a slow-release somatostatin analog, on left ventricular morphology and function and on the prevalence of ventricular arrhythmic events in 19 patients with active, newly diagnosed, uncomplicated acromegaly. Cardiac features were evaluated with Doppler-echocardiography and 24-h Holter ECG monitoring at baseline and after 6 months of lanreotide therapy. Fifteen patients (78.9%) had left ventricular hypertrophy. Lanreotide treatment significantly decreased the left ventricular mass (127.8+/-6.9 vs 140.7+/-7.1 g/m2, p<0.001) and left ventricular hypertrophy significantly disappeared in 6 of these patients. Treatment did not significantly affect systolic function, whereas it increased the Doppler-derived early-to-late mitral flow velocity, (E/A) ratio, of early-to-late trans-mitral flow velocity (1.34+/-0.1 vs 1.09+/-0.06, p=0.001). Stroke volume was slightly but not significantly increased after treatment, whereas systolic BP was significantly higher (134+/-14 vs 129+/-13 mmHg, p<0.05). The 24-h mean heart rate was significantly reduced after treatment (66.5+/-11 vs 71.5+/-20 beats/min, p<0.05). Supra-ventricular premature beats (>50/24 h) occurred in 16.6% of patients and were unaffected by treatment. Differently, ventricular premature beats (>50/24 h) occurred in 33.3% of patients before treatment vs 16.5%, after treatment. In conclusion, lanreotide reduced the left ventricular mass, and improved ventricular filling and ventricular arrhythmic profile.

Acromegaly↗

Growth hormone and the heart.

Impaired cardiovascular function has recently been demonstrated to potentially reduce life expectancy both in GH deficiency and excess. Experimental and clinical studies have supported the evidence that GH and IGF-I are implicated in cardiac development. In most patients with acromegaly a specific cardiomyopathy, characterized by myocardial hypertrophy with interstitial fibrosis, lympho-mononuclear infiltration and areas of monocyte necrosis, results in biventricular concentric hypertrophy. In contrast, patients with childhood or adulthood-onset GH deficiency (GHD) may suffer both from structural cardiac abnormalities, such as narrowing of cardiac walls, and functional impairment, that combine to reduce diastolic filling and impair left ventricular response to peak exercise. In addition, GHD patients may have an increase in vascular intima-media thickness and a higher occurrence of atheromatous plaques, that can further aggravate the haemodynamic conditions and contribute to increased cardiovascular and cerebrovascular risk. However, several lines of evidence have suggested that the cardiovascular abnormalities can be partially reversed by suppressing GH and IGF-I levels in acromegaly or after GH replacement therapy in GHD patients. Recently, much attention has been focussed on the ability of GH to increase cardiac mass suggesting its possible use in the treatment of chronic nonendocrine heart failure. In fact, GH administration can induce an improvement in haemodynamic and clinical status in some patients. Although these data need to be confirmed in more extensive studies, such promising results seem to open new perspectives for GH treatment in humans.

Acromegaly↗

Increased arterial intima-media thickness by B-M mode echodoppler ultrasonography in acromegaly.

BACKGROUND: Patients with acromegaly have an increased morbidity and mortality for cardiovascular diseases. Despite the increasing evidence for the existence of a specific cardiomyopathy in acromegaly, the presence of vascular abnormalities has been never investigated. OBJECTIVE: To evaluate the cardiovascular risk and premature atherosclerosis in acromegaly. SUBJECTS: Forty-five patients with acromegaly and 30 sex- and age-matched healthy subjects were included in this study: 30 patients were studied at the diagnosis of acromegaly and were in active disease (GH 59.3 +/- 10.2 mU/l, IGF-I 733 +/- 57.6 microg/l) while 15 patients were studied after surgery and/or radiotherapy and were cured from the disease (GH 4.5 +/- 0.7 mU/l, IGF-I 172.4 +/- 16.9 microg/l). METHODS: Body mass index (BMI), systolic (SBP) and diastolic blood pressure (DBP), serum total, LDL- and HDL-cholesterol, triglycerides, and fibrinogen levels, prothrombin time (PT), activated partial thromboplastin time (APTT), glucose and insulin levels (fasting and after glucose load) were measured in all patients and controls. By echodoppler ultrasonography, blood systolic (SPV) and diastolic (DPV) peak velocity, and resistance index (RI) were measured at both common and internal carotid arteries where presence, size and location of atherosclerotic plaques were evaluated by B-Mode ultrasonography. Intima-media thickness (IMT) of both common carotids was measured by M-Mode ultrasonography. RESULTS: SBP, but not DBP, was significantly higher in patients with active disease than in cured patients and controls (P = 0.003). Hypertension was found in nine (30%) patients with active disease, in two (13.3%) of those cured from acromegaly and in none of controls (chi2 = 10.81, P < 0.004). Fasting blood glucose levels were significantly higher both in patients with active disease and in those cured from the disease than in controls (P < 0.001). Circulating insulin levels were significantly higher in patients with active disease than in cured patients and controls (P < 0.001) and in cured patients than in controls (P < 0.001). Glucose tolerance abnormalities were found in 13 (43.3%) patients with active disease, in four (26.6%) patients with inactive disease and in four controls (13.3%) (chi2 = 6.71, P = 0.03). Total blood cholesterol levels were similar in the three groups, LDL-cholesterol and triglycerides levels were significantly higher, whereas HDL-cholesterol levels were significantly lower both in patients with active disease and in those cured from the disease than in controls (P < 0.001). Serum fibrinogen levels were significantly higher both in patients with active disease and in those cured from the disease than in controls (P < 0.001). No difference was found in PT and APTT levels among the three groups. At the level of right and left common carotid arteries, IMT was significantly higher both in patients with active disease and in those cured from the disease than in controls (P < 0.001). Both right and left SPV, but not DPV, were significantly higher in patients with active disease than in those cured from the disease and in controls (P < 0.01). Well defined carotid wall plaques were detected in two patients (6.6%) with active disease, in one patient cured from the disease (6.6%) and in two controls (6.6%). At the level of right and left internal carotid arteries, SPV, DPV and RI were similar among the three groups. Well defined carotid wall plaques were detected in three patients with active disease (10%), two patients cured from the disease (13.3%) and in one control (3.3%). CONCLUSIONS: A significant increase of IMT of both common carotid arteries was observed in patients with active acromegaly, this was also found in those cured from acromegaly. However, the prevalence of well defined carotid plaques was not increased in both groups of patients with acromegaly as compared to controls. On this basis, heart more than vessels seems to be affected by chronic GH and IGF-I excess in acromegaly.

Acromegaly↗

Is the acromegalic cardiomyopathy reversible? Effect of 5-year normalization of growth hormone and insulin-like growth factor I levels on cardiac performance.

Acromegalic patients are considered to be exposed to a doubled mortality rate, mostly for cardiovascular diseases. This open prospective study was designed to evaluate whether the impairment of cardiac performance could be reversed by the long-term suppression of GH and insulin-like growth factor I (IGF-I) levels. Eighteen patients with active acromegaly were studied before and 5 yr after surgery, followed by sc octreotide in 11 patients. Disease control (GH levels < or =1 microg/L after glucose load or < or =2.5 microg/L after fasting, respectively, together with normalized IGF-I levels for age) was achieved in seven patients after surgery and in six patients after 0.3--0.6 mg/day sc octreotide. Five patients were not controlled during the 5-yr follow-up. Cardiac performance at rest and at peak exercise was assessed by equilibrium radionuclide angiography at study entry and 5 yr after surgery alone or plus octreotide. Thirty-six sex- and age-matched healthy subjects served as controls. At study entry, patients had a lower left ventricular ejection fraction (LVEF) at peak exercise and LVEF exercise-induced changes, exercise duration, and capacity than controls (P < 0.001). After 5 yr of treatment, a significant decrease of resting heart rate (P = 0.03) and a significant increase of LVEF at peak exercise (P = 0.003) was found in patients achieving disease control. LVEF response at peak exercise worsened in none of the patients with controlled disease and in three patients with uncontrolled disease (60%) (chi(2) = 5.5; P = 0.02). Diastolic filling, exercise duration, and workload did not significantly change during the 5-yr follow-up. No difference was found between patients controlled by surgery alone or by surgery plus octreotide. This 5-yr prospective study demonstrated that the LVEF response at peak exercise improved in all patients achieving disease control, while it was worsened in 60% of uncontrolled ones. These results strengthen the need of a stable suppression of GH and IGF-I hypersecretion to restore a normal cardiac performance in acromegaly.

Acromegaly↗

Long-term effects of depot long-acting somatostatin analog octreotide on hormone levels and tumor mass in acromegaly.

The effects of a 12- to 24-month treatment with depot long-acting octreotide (OCT-LAR) on hormone profile, tumor mass, and clinical symptoms were reported in 36 patients with active acromegaly [GH, 34.2 +/- 5.6 microg/L; insulin-like growth factor I (IGF-I), 784.5 +/- 40.4 microg/L]. Fifteen patients were de novo whereas 21 had previously undergone unsuccessful surgery. Serum GH (P < 0.0001) and IGF-I levels (P < 0.0001) significantly decreased as early as after the first injection of OCT-LAR and progressively declined during the 12-24 months of treatment both in de novo and in operated patients. At the last follow-up, GH hypersecretion was controlled (< or =2.5 microg/L) in 69.4% whereas normal IGF-I levels were achieved in 61.1% of patients. GH and IGF-I suppression during OCT-LAR treatment was similar in de novo and operated patients as shown by nadir GH (2.3 +/- 0.6 vs. 2.2 +/- 0.6 microg/L) and IGF-I (323.1 +/- 34.9 vs. 275.5 +/- 33.0 microg/L), percent suppression of GH (92.7 +/- 2.0 vs. 85.9 +/- 3.3%) and IGF-I (57.4 +/- 4.9 vs. 61.5 +/- 4.6%), and prevalence of GH (73.3 vs. 76.2%) and IGF-I (53.3 vs. 71.4%) control. A decrease in tumor volume was observed in 12 of 15 de novo patients, whereas no shrinkage was detected in 4 of 9 operated patients. No patient had tumor reexpansion during OCT-LAR treatment. Significant clinical improvement was obtained in all patients; heart rate, systolic blood pressure, and diastolic blood pressure significantly decreased in the entire population. A mild but significant increase of blood glucose levels, followed by a decrease of serum insulin levels, was observed after 3 months of treatment: this effect subsided with treatment continuation. OCT-LAR treatment was well tolerated by most patients. In conclusion, long-term treatment with OCT-LAR was effective in controlling GH and IGF-I hypersecretion in most patients with acromegaly, when applied either as primary therapy or as adjunctive therapy after surgery. Tumor shrinkage was observed in de novo patients during OCT-LAR treatment, suggesting that it can be successfully applied as primary therapy in patients bearing invasive tumors, who are less likely to be cured after surgery.

Acromegaly↗

Usefulness of different biochemical markers of the insulin-like growth factor (IGF) family in diagnosing growth hormone excess and deficiency in adults.

The diagnostic approach to acromegaly and GH deficiency frequently includes measurement of several components of the insulin-like growth factor (IGF) system. IGF-I levels are reported to be good predictors of active and cured acromegaly, but are commonly found within the normal age-adjusted range in adult GH-deficient (GHD) patients. Circulating concentrations of IGF-binding protein-3 (IGFBP-3), acid-labile subunit (ALS), and free IGF-I reflect the GH secretory status, but their diagnostic accuracy is still debated. In this study serum levels of total and free IGF-I, IGFBP-3, ALS, and IGFBP-3-IGF-I and IGFBP-3-ALS complexes were determined in patients previously diagnosed with active (n = 67) or inactive (n = 16) acromegaly and adult GHD (n = 34) and compared with results obtained in 58 healthy controls. In healthy subjects, IGF-I, IGFBP-3, ALS, and both IGFBP-3 complexes declined with age; a correlation was found between IGF-I and IGFBP-3 (r = 0.59; P < 0.001), ALS (r = 0.67; P < 0.001), and free IGF-I (r = 0.40; P < 0.05). Active acromegalic patients showed a significant increase in all parameters tested. IGF-I concentrations were above +2 SD in 100% of patients, whereas slightly lower sensitivities were shown for IGFBP-3 (85%), ALS (88%), and free IGF-I (94%). In this group, IGF-I exhibited a slightly higher correlation with IGFBP-3 (r = 0.83; P < 0.001) than with ALS levels (r = 0.78; P < 0.001). In cured acromegalic patients, we observed the normalization of all parameters but free IGF-I levels. Adult GHD patients showed a significant reduction of all hormones. Unlike active acromegalic patients, all parameters had only a modest sensitivity in GHD; suppression below -2 SD was observed in 41% of GHD patients for IGF-I, 47% for IGFBP-3, 32% for ALS, and 35% for free IGF-I measurements. Previous radiotherapy and GH peak response below 3 microg/L were associated with significantly lower IGF-I, IGFBP-3, and ALS levels. IGF-I levels were significantly correlated to ALS (r = 0.68; P < 0.001) and IGFBP-3 (r = 0.64; P < 0.001) as well as with free IGF-I (r = 0.67; P < 0.001) levels. By multiple regression analysis, the number of anterior pituitary hormones impaired was the most predictive indicator of IGF-I, IGFBP-3, and free IGF-I levels in GHD patients; conversely, the GH peak response better anticipated ALS concentrations. The pattern of IGFBP-3 complexes paralleled previous hormonal findings. In active acromegalic patients, IGFBP-3-IGF-I levels were 5.4-fold higher than in controls and were above +2 SD in 95% of patients, whereas IGFBP-3-ALS levels were elevated in 15% of cases. On the other hand, both IGFBP-3 complexes were able to predict GHD in only a minority of cases. Taken together, these data support the diagnostic role of IGF-I in acromegaly and suggest that free IGF-I and the IGFBP-3-IGF-I complex can assist diagnostic strategies in this condition. All markers are of limited predictive value in adult GHD, as hormonal values are commonly found within the normal limits. In these patients, low IGFBP-3 and IGF-I concentrations can add further clinical information on the residual GH activity.

Acromegaly↗

The effect of quinagolide and cabergoline, two selective dopamine receptor type 2 agonists, in the treatment of prolactinomas.

OBJECTIVE: To compare effectiveness and tolerability of quinagolide (CV 205-502) and cabergoline (CAB) treatments in 39 patients with prolactinoma. STUDY DESIGN: All 39 patients were treated first with quinagolide for 12 months and then with cabergoline for 12 months. A wash-out period was performed in all patients after 12 months of both treatments in order to evaluate recurrence of hyperprolactinaemia. PATIENTS: Twenty-three patients with microprolactinoma (basal serum PRL levels 1620-18750 mU/l) and 16 patients with macroprolactinoma (basal serum PRL levels 4110-111000 mU/l), previously shown to be intolerant of bromocriptine. All patients had gonadal failure and 11 patients with macroprolactinoma had visual field defects. Five patients with macro- and one with microprolactinoma had previously undergone surgery. STUDY PROTOCOL: The starting doses of quinagolide and CAB were 0.075 mg/day and 0.5 mg/week, respectively, subsequently increased up to 0.6 mg once daily and 1.5 mg twice weekly, respectively. Serum PRL levels were measured monthly for the first 3 months and then quarterly for 12 months. PRL levels were assayed weekly for the first month and then monthly during the wash-out period. Tumour shrinkage was evaluated by serial magnetic resonance imaging (MRI) studies of the hypothalamus-pituitary region at study entry and after 6 and 12 months of both treatments in micro- and macroprolactinomas. RESULTS: After 12 months of quinagolide treatment, serum PRL levels normalized in all 23 patients with microprolactinoma (100%) and in 14 out of 16 with macroprolactinoma (87.5%). A tumour volume reduction of greater than 80% was documented by MRI studies in five of 23 (21.7%) patients with microprolactinoma and in four of 16 (25%) with macroprolactinoma. All patients had recurrence of hyperprolactinaemia after 15-60 days withdrawal of quinagolide treatment. However, before starting CAB treatment basal PRL levels were significantly lower than before quinagolide treatment both in microprolactinomas (4667.4 +/- 714.7 vs. 2636.1 +/- 262.3 mU/l, P = 0.006) and in macroprolactinomas (24853.1 +/- 7566.7 vs. 3576.6 +/- 413.0 mU/l, P = 0.013). After 12 months of CAB treatment, serum PRL levels normalized in 22 out of 23 patients with microprolactinoma (95.6%) and in 14 out of 16 with macroprolactinoma (87.5%). No difference in PRL nadir was found after quinagolide and CAB treatments both in micro 174.6 +/- 30.6 vs. 169.8 +/- 37.9 mU/l, P = 0.5) and in macroprolactinomas (277.5 +/- 68.4 vs. 341.8 +/- 95.2 mU/l, P = 0.6). A tumour volume reduction of greater than 80% was documented by MRI studies in seven other patients with microprolactinoma (30.4%) and in five other patients with macroprolactinoma (31.2%). After CAB treatment, further tumour shrinkage ranging 4-40% and 2-70% was observed in 12 micro- and seven macroprolactinomas, respectively. The percentage of tumour shrinkage after CAB was significantly higher than that observed after quinagolide in microprolactinomas (48.6 +/- 9.5 vs. 26.7 +/- 4. 5%, P = 0.046) but not in macroprolactinomas (47.0 +/- 10.6 vs. 26.8 +/- 8.4%, P = 0.2). The withdrawal from CAB treatment, induced an increase in serum PRL levels in all macroprolactinomas between 15 and 30 days, in 15 out of 23 microprolactinoma after 30 days, and in four patients after 2-4 months. In the remaining four patients serum PRL levels remained normal after 12 months of CAB withdrawal. Both compounds were tolerated satisfactorily by all patients. In the first week of quinagolide treatment, 12 patients reported nausea and postural hypotension, which spontaneously disappeared during the second-third week of treatment. None of the 39 patients reported side-effects during CAB treatment. CONCLUSIONS: Both quinagolide and CAB treatments, induced the normalization of serum PRL levels in the great majority of patients with prolactinoma. Tumour shrinkage was recorded in 22-25% of patients after quinagolide and in 30-31% after CAB treatment

Adult↗

Increased prevalence of thyroid autoimmunity in patients successfully treated for Cushing's disease.

BACKGROUND: Cushing's disease is characterized by abnormalities of immune function. OBJECTIVE: To evaluate the prevalence of autoimmune thyroid diseases in patients with Cushing's disease (CD), after successful treatment and the possible association between previous nodular goitre or positive thyroid autoantibodies during the active phase of CD and the subsequent development of autoimmune thyroid diseases after cure. SUBJECTS AND METHODS: Twenty patients with CD and 40 sex- and age-matched healthy controls were considered for the study. In CD patients, thyroid ultrasonography and measurement of circulating free thyroxine (fT4), free triiodothyronine (fT3), thyroid stimulating hormone (TSH), antithyroglobulin (anti-Tg) and antithyroperoxidase (anti-TPO) antibodies were performed at diagnosis and 6 months after disease cure while in controls they were performed only at study entry. RESULTS: Serum fT3, and fT4 levels were similar in patients, either during the active phase or after cure of the disease, and controls. Conversely, in the patients, serum TSH levels were significantly lower during active disease (0. 4 +/- 0.05 mU/l, P = 0.001) and significantly higher after disease cure (4.7 +/- 0.1 mU/l, P < 0.001) than in controls (2.3 +/- 0.4 mU/l). Four patients (20%) and 11 controls (27.5%) had positive anti-Tg and/or anti-TPO titre at study entry, while eight patients (40%) developed positive anti-Tg and/or anti-TPO titre after disease cure. The prevalence of positive antithyroid antibodies titre in cured CD patients was significantly higher than that observed in the same patients during the active disease (P = 0.008) and in controls (P = 0.031). A significantly higher prevalence of autoimmune thyroiditis was found in patients cured from CD (35%) than in patients with active CD (0%) (P = 0.016) and in controls (10%) (P = 0.031). A significant association was found between the presence of autoimmune thyroiditis after CD cure and the presence of a previous nodular goitre (P = 0.017) or positive thyroid autoantibodies titre (P = 0.007) during the active phase of the disease. CONCLUSION: Patients successfully treated for Cushing's disease have an increased prevalence of thyroid autoimmunity and autoimmune thyroiditis as compared to a control population. Therefore, patients with hypercortisolism need an accurate evaluation of thyroid function after remission of the disease in order to prevent the eventual onset of subclinical or overt post-thyroiditis hypothyroidism.

Adult↗

Clinical evidence for myocardial derecruitment downstream from severe stenosis: pressure-flow control interaction.

To verify the interaction between coronary pressure (CP) and blood flow (CBF) control, we studied nine candidates for angioplasty of an isolated lesion of the left anterior descending coronary artery [i.e. , percutaneous transluminal coronary angioplasty (PTCA)]. CBF (i.e., flow velocity x coronary cross-sectional area at the Doppler tip) and CP were monitored during washout of 2-5 mCi of (133)Xe after bolus injection into the left main artery before and after PTCA. Xe mean transit time (MTT) was calculated as the area under the time-activity curve, acquired by a gamma camera, divided by the dose obtained from a model fit of the Xe curve in the anterior wall. CBF response to intracoronary adenosine (2 mg) was also assessed. PTCA increased baseline CBF (from 14.5 +/- 9.4 to 20 +/- 8 ml/min, P < 0.01), coronary flow reserve (from 1.52 +/- 0.24 to 2.33 +/- 0.8, P < 0.01), and CP (from 64 +/- 9 to 100 +/- 10 mmHg, P < 0.05). MTT decreased from 89 +/- 32 to 70 +/- 19 s (P < 0.05) after PTCA; however, MTT and CBF changes were not correlated (r = -0.09, not significant). Inasmuch as MTT is the ratio of distribution volume to CBF, MTT x CBF was used as an index of perfused myocardial volume. Volume increased after PTCA from 23 +/- 18 to 56 +/- 30 ml. A direct correlation was observed between the percent increase in distal CP and percent increase in perfused volume (r = 0.91, P < 0.01). Thus low CP was not associated with exhaustion of flow reserve but, rather, with reduction of perfused myocardial volume. These data suggest that, in the presence of a severe coronary stenosis, derecruitment of vascular units occurs that is proportional to the decrease in driving pressure. Residual perfused units maintain a vasomotor tone, thus explaining the paradoxical persistence of coronary reserve.

Angioplasty, Balloon, Coronary↗

New medical approaches in pituitary adenomas.

Recently, the medical approach to patients with secreting and clinically non-functioning pituitary adenomas has received great impulse thanks to the availability of new, selective and long-lasting compounds with dopaminergic activity, such as cabergoline, and of somatostatin analogues provided in slow-release formulations, such as lanreotide and octreotide long acting release (LAR). In particular, the use of cabergoline has induced control of hyperprolactinaemia and tumour shrinkage in the great majority of patients with micro- and macroprolactinomas. Cabergoline treatment restores fertility both in women and men, and partially improves osteoporosis, one of the major complications of hyperprolactinaemia. In acromegaly, disease control (growth hormone [GH] <2.5-1.0 microg/l as a fasting or glucose-suppressed value, respectively, together with age-normalised insulin-like growth factor [IGF]-I) is achievable in more than half of patients receiving treatment with lanreotide or octreotide-LAR. Improvement in cardiomyopathy, sleep apnoea and arthropathy has been reported during GH/IGF-I suppression after pharmacotherapy. A synthetic GH analogue, B2036-PEG, that antagonises endogenous GH binding to its receptor-binding sites and a GH-releasing hormone antagonist that blocks the effect of this releasing factor on the hypothalamus and pituitary are presently under investigation in acromegaly. Preliminary studies have clearly demonstrated the effectiveness of the GH receptor antagonist in suppressing IGF-I levels in acromegalic patients previously unresponsive to somatostatin analogues. Beneficial effects of subcutaneous octreotide and lanreotide have also been reported in adenomas secreting thyroid-stimulating hormone, while the results of treatment with dopamine agonists or somatostatin analogues remain disappointing in patients with clinically non-functioning adenomas. In these patients the possibility of visualising in vivo the expression of D(2) receptors using specific radiotracers such as (123)I-methoxybenzamide has allowed selection of patients likely to respond to cabergoline. Scant effects of pharmacotherapy have also been reported in patients with adenomas secreting adrenocorticotropic hormone. However, some preliminary data suggest a potential use of cabergoline in combination with ketoconazole, or alone, in selected cases of Cushing's disease or Nelson's syndrome.

Adenoma↗

Systemic hypertension and impaired glucose tolerance are independently correlated to the severity of the acromegalic cardiomyopathy.

Increased mortality from cardiovascular diseases has been reported in acromegaly. Our objective was to evaluate the impact of glucose tolerance abnormalities and/or systemic hypertension in further worsening the acromegalic cardiomyopathy. The study design was open transversal. The subjects studied were 130 consecutive naive acromegalic patients (74 women and 56 men; age, 17-80 yr). Interventricular septum (IST) and left ventricular (LV) posterior wall thickness (PWT), LV mass index (LVMi), maximal early to late diastolic flow velocity ratio (E/A), isovolumic relaxation time (IRT), and LV ejection fraction (EF) were measured by echocardiography. The results were analyzed in line with the presence of glucose tolerance abnormalities (normal in 60, impaired in 38, diabetes mellitus in 32) and the presence (in 46) or absence (in 84) of hypertension. Patients with impaired glucose tolerance and diabetes mellitus had significantly higher age (P = 0.01), and systolic (P = 0.01) and diastolic (P = 0.01) blood pressures and lower E/A (P = 0.01) and EF (P = 0.01) than those with normal glucose tolerance. Disease duration, circulating GH and insulin-like growth factor I (IGF-I) levels, IST, LVPWT, LVMi, and IRT were similar in the 3 groups. Normotensive patients had significantly lower age (P<0.001), LVPWT (P<0.001), IST (P = 0.003), LVMi (P<0.001), and IRT (P = 0.02) and significantly higher E/A (P<0.001) and EF (P<0.001) than hypertensive subjects. Disease duration, circulating GH, and IGF-I levels were similar in the 2 groups. Multiple regression analysis showed that systolic blood pressure was the strongest predictor of LVMi (P = 0.0004), followed by GH levels (P = 0.02), whereas diastolic blood pressure was the strongest predictor of LVEF reduction (P<0.0001), followed by glucose tolerance status (P = 0.02). Age was the strongest predictor of both E/A impairment (P<0.0001) and IRT (P = 0.01), followed by IGF-I levels (P = 0.02). Compared to patients with uncomplicated acromegaly, those with hypertension but without abnormalities of glucose tolerance had an increased prevalence of LV hypertrophy (75% vs. 37.2%) as well as of impaired diastolic (50% vs. 7.8%) and systolic function (18.7% vs. 3.9%), whereas patients with glucose tolerance abnormalities but without hypertension had only an increased prevalence of impaired diastolic (39.7%) and systolic function (31.7%). The subgroup of acromegalic patients suffering from hypertension and diabetes mellitus had the highest prevalence of LV hypertrophy (84.6%), diastolic filling abnormalities (69.2%), and impaired systolic function at rest (53.9%). A careful cardiac investigation should thus be performed in all acromegalic patients showing these complications.

Acromegaly↗

Effect of two years of growth hormone and insulin-like growth factor-I suppression on prostate diseases in acromegalic patients.

The insulin-like growth factors (IGFs) have mitogenic effects on normal and tumoral prostate epithelial cells and have been suggested to be involved in prostate cancer. Moreover, chronic GH and IGF-I excess causes prostate overgrowth in patients with acromegaly. This study was designed to investigate whether the suppression of GH and IGF-I levels by surgery or pharmacotherapy could induce the regression of prostatic hyperplasia in acromegalic patients. To this end, prostate volume (PV) as well as the occurrence of prostatic diseases were studied by transrectal ultrasonography in 23 untreated acromegalic patients (with elevated GH and IGF levels). None of the patients reported symptoms due to prostatic disorders or obstruction. At study entry, prostate hyperplasia was found in half patients. After 2 yr, GH, IGF-I, and IGFBP-3 levels were decreased, whereas prostate-specific antigen levels did not change. PV was decreased in the 16 patients who were well controlled. Among the 6 patients with prostate hyperplasia at study entry who achieved disease control, 4 regained a normal PV at the end of the 2 yr of treatment, whereas none of the 5 patients with prostate hyperplasia at study entry and not achieving disease control normalized their PV. When patients were divided according to age, prostate volume decreased after 2 yr only in the 8 controlled patients aged below 50 yr, but not in those controlled and with age above 50 yr despite similar decrease in GH, IGF-I, and IGFBP3 levels. No clinical, transrectal ultrasonography, or cytological evidence of prostate cancer was detected during the study period. These data suggest that hyperplasia, but not cancer, is frequent in acromegalic men, and that the GH-IGF axis and age are independently associated with the development of this process.

Acromegaly↗

Two-year follow-up of acromegalic patients treated with slow release lanreotide (30 mg).

Pharmacotherapy of acromegaly has been improved in recent years as new long-acting somatostatin analogs have became available; they have been suggested as an alternative treatment to pituitary surgery and radiotherapy. To avoid the inconvenience of multiple daily injections during long-term therapy, a slow release formulation of lanreotide (LAN), to be administered im at a dose of 30 mg every 7-14 days, has been introduced in the therapeutic management. The suppressive effects of a short-term LAN treatment on GH and insulin-like growth factor I (IGF-I) hypersecretion were shown to be similar to those obtained with sc octreotide. However, scant data have been reported concerning a long-term treatment with this drug. In the present study the efficacy and tolerability of a 24-month LAN treatment were evaluated in 118 active acromegalic patients; 71 had been previously operated on and treated with s.c. octreotide (operated patients), 24 previously operated on had been irradiated and treated with s.c. octreotide (irradiated patients), and the remaining 23 were newly diagnosed (de novo patients). The efficacy was considered on the basis of controlled GH (fasting, <7.5 mU/L; glucose-suppressed, <3.0 mU/L) and IGF-I (age-adjusted normal values) secretion. In the 118 patients as a whole, circulating GH and IGF-I levels were significantly decreased during the 24-month LAN treatment (P < 0.0005 at all time points vs. basal value). After 24 months of therapy, controlled GH and IGF-I levels were achieved in 64%, 37%, and 78% and in 51%, 37%, and 70% of operated, irradiated, and de novo patients, respectively. A reduction in tumor size was documented in 5 of 23 de novo patients (22%). Among the 84 operated/irradiated with evident tumor remnant, significant shrinkage was documented in 5 patients (5.9%). Treatment was well tolerated by the majority of patients. Only 2 patients (1.7%) withdrew from LAN treatment due to severe side effects. In conclusion, a 24-month treatment with slow release lanreotide (30 mg) is effective in reducing GH and IGF-I levels; furthermore, in de novo patients it induces disease control in 70% of patients and causes tumor shrinkage in 22% of them, with excellent compliance. These data suggest that LAN can be used in long-term treatment of acromegalic patients.

Acromegaly↗

Cardiac effect of thyrotoxicosis in acromegaly.

Cardiac structure and function are affected both by acromegaly and hyperthyroidism. Whereas the former is mainly characterized by ventricular hypertrophy as well as diastolic and systolic impairment, the latter frequently leads to increased heart rate and enhancement of contractility and cardiac output. To further investigate this issue, we designed this two-arm study. In the first cross-sectional study, we compared echocardiography and radionuclide angiography results obtained in eight hyperthyroid acromegalic patients, eight hyperthyroid nonacromegalic patients, and eight healthy subjects. All acromegalic patients were receiving treatment for acromegaly at the onset of hyperthyroidism. In the second longitudinal study, performed in the group of acromegalic patients, we compared the cardiovascular results obtained during hyperthyroidism with the retrospective data obtained at the initial diagnosis of acromegaly and after 1-yr treatment for this disease and those prospective data obtained during the remission of hyperthyroidism. In the cross-sectional study, hyperthyroid acromegalic patients showed an increase in the left ventricular (LV) mass index (LVMi) compared to healthy and hyperthyroid controls (P < 0.05), with evidence of LVMi hypertrophy in five of them (62.5%). A significant correlation was found between LVMi and GH levels (r = 0.785; P < 0.05). The LV ejection fraction (LVEF) at rest was higher in the control hyperthyroid population than in healthy controls (P < 0.05), whereas the LVEF response to exercise was reduced in acromegalic patients (P < 0.05 vs. healthy controls). In acromegalics, the exercise-induced change in LVEF was significantly reduced compared to that in healthy controls (P < 0.001), but not to that in hyperthyroid controls (P < 0.07), being abnormal (<5% increase vs. baseline values) in six patients. Four of these six patients (66%) had elevated GH and insulin-like growth factor I levels during the treatment of acromegaly. An inverse correlation between GH and LVEF at rest (r = -0.896;P < 0.05) and at peak exercise (r = -0.950; P < 0.001) was recorded. The peak filling rate was reduced in hyperthyroid acromegalic patients compared to those in both control populations (P < 0.05). In the longitudinal study, acromegalic patients showed an increased LVMi during hyperthyroidism compared to that observed after successful treatment of acromegaly (P < 0.05); resting LVEF was increased compared to both basal (P < 0.001) and posttreatment values (P < 0.05). However, the exercise-induced change in LVEF was reduced (P < 0.05 vs. previous follow-up values). Remission of hyperthyroidism led to significant reduction of LVMi (P < 0.05) and resting LVEF (P < 0.05) and an increase in exercise-induced LVEF (P < 0.05). In light of these findings, hyperthyroidism produces a detrimental effect on the cardiovascular system of acromegalic patients, particularly in those with uncontrolled disease. Thus, control of GH and insulin-like growth factor I should be a major objective, as cardiovascular risk persists in patients with ineffective hormonal suppression, and constant endocrine and cardiovascular surveillance remain crucial steps in patient follow-up.

Acromegaly↗

Cardiovascular effects of depot long-acting somatostatin analog Sandostatin LAR in acromegaly.

Cardiovascular disease is the most severe complication of acromegaly accounting for the increased mortality of these patients. Recently, the slow-release form of octreotide (OCT; Sandostatin LAR, OCT-LAR), for im injection every 28 days, was reported to induce suppression of GH levels below 7.5 mU/L (2.5 microg/L) in 39-75% of patients, and normalization of insulin-like growth factor (IGF)-I levels for age in 64-88% of patients, with an excellent patients' compliance. The aim of the present study was to investigate the early effect of OCT-LAR treatment on the left ventricular (LV) structure and performance in 15 somatostatin analog-naive patients with acromegaly (GH, 94.8 +/- 24.9 mU/L; IGF-I, 757.9 +/- 66.6 microg/L), focusing on the early effect of GH and IGF-I suppression on the heart. Cardiac structure was investigated by echocardiography, whereas LV performance was investigated by gated-blood-pool scintigraphy, before and after 3 and 6 months of treatment with OCT-LAR. OCT-LAR was initially administered im, at a dose of 20 mg every 28 days, for 3 months. In six patients, the dose was then increased to 30 mg every 28 days to achieve disease control, which was considered when fasting and/or glucose-suppressed GH values were below 7.5 and 3.0 mU/L, respectively, together with IGF-I values within the normal range for age. The treatment with OCT-LAR for 6 months induced a significant decrease of GH (to 12.9 +/- 3.0 mU/L) and IGF-I levels (to 340.3 +/- 40.2 microg/L) in all 15 patients. After 6 months of treatment, the percent IGF-I suppression was 52.8 +/- 4.4%, and serum GH/IGF-I levels were normalized in 9 patients. A significant decrease of LV mass index (LVMi), interventricular septum thickness, and LV posterior wall thickness was observed in all 15 patients after 3 and 6 months of OCT-LAR treatment: LVMi was decreased by 19.1 +/- 2.0% without any difference in patients with (19.9 +/- 2.7%) or without disease control (17.8 +/- 3.3%). Among the 11 patients with LV hypertrophy, 6 normalized their LVMi after treatment. At study entry, an inadequate LV ejection fraction (LVEF) at rest (<50%) was found in 5 patients (33.3%), whereas an impaired response of LVEF at peak exercise (<5% increase of basal value) was found in 9 patients (60%). A significant increase in LVEF, both at rest (from 51.6 +/- 2.6 to 58.1 +/- 1.7%, P < 0.01) and at peak exercise (from 51.6 +/- 2.3 to 60.2 +/- 2.4%, P < 0.001) was found in patients with (as compared with those without) disease control (from 55.2 +/- 3.8 to 58.0 +/- 4% and from 61.8 +/- 4.6 to 61.8 +/- 3.4%, respectively). Among the 5 patients with inadequate LVEF at rest, all but 1 regained a normal LVEF after 6 months of treatment; whereas, among the 9 patients with an impaired response of the LVEF at peak exercise, 3 patients normalized, 4 improved, and 2 impaired their responses after treatment. The percent of IGF-I suppression was significantly correlated with the percent increase of resting LVEF (r = 0.644, P < 0.01). Exercise duration (from 6.0 +/- 0.7 to 7.3 +/- 0.7 min) and capacity (from 69.0 +/- 8.2 to 80 +/- 7.8 watts) were increased in the 15 patients considered as a whole, but the improvement in the exercise response was significant only in patients with disease control (P < 0.01 and P < 0.05, respectively) who also had an increase in the peak ejection rate (P = 0.03). No change in hemodynamic parameters, either at rest or at peak exercise, was found after treatment with OCT-LAR in the 15 patients. In conclusion, the results of the present study demonstrate that OCT-LAR im injections every 28 days induces a sustained suppression of GH levels and IGF-I levels in all acromegalic patients, allowing achievement of disease control in 60% of patients after 6 months of treatment. The sustained suppression of IGF-I levels was followed by a significant reduction of LVMi in all patients already after 3 months of treatment, with recovery of LV hypertrophy in 6 of 11 patients. (ABSTRACT TRUN

Acromegaly↗

Muscle sympathetic nerve activity in patients with acromegaly.

Muscle sympathetic nerve activity was measured in nine acromegalic patients (age, 35 +/- 4 yr; body mass index, 28 +/- 2 kg/m2) and eight healthy subjects (age, 32 +/- 3 yr; body mass index, 25 +/- 2 kg/m2) by combining the forearm arterial-venous difference technique with the tracer method [infusion of tritiated norepinephrine (NE)]. Muscle NE release was quantified both at rest and during physiological hyperinsulinemia while maintaining euglycemia (approximately 90 mg/dL) by means of the euglycemic clamp. Arterial plasma NE was similar in the two groups at rest (197 +/- 28 and 200 +/- 27 pg/mL (-1) and slightly increased during insulin infusion. Forearm NE release was 2.33 +/- 0.55 ng x liter(-1) x min(-1) in healthy subjects and 2.67 +/- 0.61 ng x liter(-1) x min(-1) in acromegalic subjects in the basal state and increased to a similar extent during insulin infusion in both groups (3.13 +/- 0.71 and 3.32 +/- 0.75 ng x L(-1) x min(-1), P < 0.05 vs. basal), indicating a normal stimulatory effect of insulin on muscle sympathetic activity. In contrast, insulin-stimulated forearm glucose uptake was markedly lower in acromegalic patients (2.3 +/- 0.4 mg x L(-1) x min(-1)) than in control subjects (7.9 +/- 1.3 mg x L(-1) x min(-1), P < 0.001), indicating the presence of severe insulin resistance involving glucose metabolism. Our data demonstrate that patients with long-term acromegaly have normal sympathetic activity in the skeletal muscle in the basal, postabsorptive state and normal increments in NE spillover in response to the sympatho-excitatory effect of insulin. Thus, the presence of severe insulin resistance in acromegaly is not accounted for by adrenergic mechanisms.

Acromegaly↗