ACROMORFO study: gait analysis in a cohort of acromegalic patients

PURPOSE

In acromegaly, skeletal complications resulted to be associated with low quality of life (QoL) and high risk of falls. The aim of the present study was to perform a quantitative assessment of movement through gait analysis technique in patients with acromegaly.

STUDY POPULATION

Thirty-three acromegalic patients [9 with active disease (AD), 14 with controlled disease (CD) and 10 with disease remission (RD)] and 20 healthy subjects were enrolled for the study.

MEASUREMENTS

Kinetic and kinematic data were collected with 3D-gait analysis. Kinematic data were processed to compute the Gait Profile Score (GPS), a parameter that summarizes the overall deviation of kinematic gait data relative to unaffected population.

RESULTS

The acromegalic group showed longer stance phase duration (p < 0.0001) compared to controls. The GPS and several gait variable scores resulted to be statistically higher in the acromegalic group compared to healthy controls. GPS values were significantly higher in AD compared to CD (p < 0.05) and RD groups (p = 0.001). The AD group presented significantly higher values in terms of hip rotation and ankle dorsiflexion compared to CD and RD groups and with regard to the foot progression compared to RD. Interestingly, patients with RD exhibited a more physiological gait pattern.

CONCLUSION

Acromegalic patients showed quantitative alterations of gait pattern, suggesting instability and increased risk of falls. Arthropathy, along with its associated abnormal joint loading, proprioceptive impairment and hyperkyphosis could be contributing factors. Disease control and remission appear to improve postural balance. A better knowledge on walking performance in acromegaly would help to develop specific rehabilitation programmes to reduce falls' risk and improve QoL.

Psychological complications in patients with acromegaly: relationships with sex, arthropathy, and quality of life

PURPOSE

Current treatment of acromegaly restores a normal life expectancy in most cases. So, the study of persistent complications affecting patients' quality of life (QoL) is of paramount importance, especially motor disability and depression. In a large cohort of acromegalic patients we aimed at establishing the prevalence of depression, to look for clinical and sociodemographic factors associated with it, and to investigate the respective roles (and interactions) of depression and arthropathy in influencing QoL.

METHODS

One hundred and seventy-one acromegalic patients (95 women and 76 men, aged 20-85 years) among those recruited in a cross-sectional Italian multicentric study were investigated. Each patient filled in three validated questionnaires: AcroQoL, WOMAC (measuring articular pain, stiffness and functionality), and AIMS (evaluating articular symptoms and depression).

RESULTS

A very high (up to 28%) depression rate was detected in acromegalic subjects. Two patients showing pathological AIMS depression scores, committed suicide during the three years observational period. In our population poor psychological status was significantly associated with female sex. Furthermore, a significant strong correlation was found between AIMS depression score and WOMAC score. Both depression and arthropathy-related motor disability turned out to independently contribute with similar strength to the impairment of QoL.

CONCLUSIONS

We report a high prevalence of depression in acromegaly, which is associated with female sex and arthropathy. Both depression and arthropathy strongly and independently contribute to the impaired QoL of patients. Our study shows that assessment and monitoring of psychological status is mandatory in acromegaly, also suggesting an inexpensive tool for this assessment.

A Multicenter Cohort Study in Patients With Primary Empty Sella: Hormonal and Neuroradiological Features Over a Long Follow-Up

OBJECTIVE

primary empty sella (PES) represents a frequent finding, but data on hormonal alterations are heterogeneous, and its natural history is still unclear. Our aim was to evaluate the pituitary function of patients with PES over a long follow-up.

DESIGN

multicenter retrospective cohort study enrolling patients referred between 1984-2020 to five Pituitary Units, with neuroradiological confirmed PES and a complete hormonal assessment.

METHODS

we analyzed hormonal (including basal and dynamic evaluations), clinical and neuroradiological data collected at diagnosis and at the last visit (at least 6 months of follow-up).

RESULTS

we recruited 402 patients (females=63%, mean age=51.5 ± 16 years) with PES (partial, total, undefined in 66%, 13% and 21%, respectively). Hypopituitarism was present in 40.5% (hypogonadism=20.4%, hypoadrenalism=14.7%, growth hormone deficiency=14.7%, hypothyroidism=10.2%, diabetes insipidus=1.5%; multiple deficiencies=11.4%) and hypeprolactinemia in 6.5%. Interestingly, hormonal alterations were diagnosed in 29% of incidental PES. Hypopituitarism was associated with male sex (p=0.02), suspected endocrinopathy (p<0.001), traumatic brain injury (p=0.003) and not with age, BMI, number of pregnancies and neuroradiological grade. A longitudinal assessment was possible in 166/402 (median follow-up=58 months). In 5/166 (3%), new deficiencies occurred, whereas 14/166 (8.4%) showed a hormonal recovery. A progression from partial to total PES, which was found in 6/98 patients assessed with a second imaging, was the only parameter significantly related to the hormonal deterioration (p=0.006).

CONCLUSIONS

this is the largest cohort of patients with PES reported. Hypopituitarism is frequent (40%) but hormonal deterioration seems uncommon (3%). Patients need to be carefully evaluated at diagnosis, even if PES is incidentally discovered.

Clinical benefits of sex steroids given as a priming prior to GH provocative test or as a growth-promoting therapy in peripubertal growth delays: Results of a retrospective study among ENDO-ERN centres

OBJECTIVES

Sex steroids, administered as a priming before GH stimulation tests (GHST) to differentiate between growth hormone deficiency (GHD) and constitutional delay of growth and puberty (CDGP) or as growth-promoting therapy using low-dose sex steroids (LDSS) in CDGP, are much debated. We aimed to compare auxological outcomes of CDGP or GHD children undergoing primed or unprimed GHST and to evaluate LDSS treatment in CDGP.

DESIGN

Retrospective study among three paediatric University Hospitals in Italy and UK.

METHODS

184 children (72 females) aged 12.4 ± 2.08 years underwent primed (/P⁺ ) or unprimed (/P^- ) GHST and were followed up until final height (FH). CDGP patients were untreated (CDG P^- ) or received LDSS (CDGP⁺ ). The cohort included 34 CDG P^- /P⁺ , 12 CDGP⁺ /P⁺ , 51 GHD/P⁺ , 29 CDG P^- /P^- , 2 CDGP⁺ /P^- and 56 GHD/P^- . FH standard deviation score (SDS), Δ SDS FH-target height (TH) and degree of success (-1 ≤ Δ SDS FH-SDS TH ≤ +1) were outcomes of interest.

RESULTS

GHD/P⁺ had better FH-SDS (-0.87 vs -1.49; P = .023) and ΔSDS FH-TH (-0.35 vs -0.77; P = .002) than CDGP^- /P⁺ . Overall, GHD/P⁺ showed the highest degree of success (90%, P = .006). Regardless of priming, both rhGH and LDSS improved degree of success compared to no treatment (89% and 86% vs 63%, P = .0009). GHD/P⁺ showed a trend towards a higher proportion of permanent GHD compared to GHD/P^- (30.43% vs 15.09%; P = .067).

CONCLUSION

In peripubertal children, priming before GHST improves diagnostic accuracy of GHST for idiopathic GHD. LDSS treatment improves auxological outcomes in CDGP.

Mortality in an Italian nursing home during COVID-19 pandemic: correlation with gender, age, ADL, vitamin D supplementation, and limitations of the diagnostic tests

INTRODUCTION

The COVID-19 pandemic caused an increased mortality in nursing homes due to its quick spread and the age-related high lethality.

RESULTS

We observed a two-month mortality of 40%, compared to 6.4% in the previous year. This increase was seen in both COVID-19 positive (43%) and negative (24%) residents, but 8 patients among those testing negative on the swab, tested positive on serological tests. Increased mortality was associated with male gender, older age, no previous vitamin D supplementation and worse "activities of daily living (ADL)" scores, such as Barthel index, Tinetti scale and S.OS.I.A.

CLASSIFICATION

CONCLUSION

Our data confirms a higher geriatric mortality due to COVID-19. Negative residents also had higher mortality, which we suspect is secondary to preanalytical error and a low sensitivity of the swab test in poorly compliant subjects. Male gender, older age and low scores on ADL scales (probably due to immobility) are risk factors for COVID-19 related mortality. Finally, mortality was inversely associated with vitamin D supplementation.

DESIGN

In this observational study, we described the two-month mortality among the 157 residents (age 60-100) of a nursing home after Sars-CoV-2 spreading, reporting the factors associated with the outcome. We also compared the diagnostic tests for Sars-CoV-2.

Arthropathy in acromegaly: a questionnaire-based estimation of motor disability and its relation with quality of life and work productivity

PURPOSE

Arthropathy is a common and disabling complication of acromegaly. Since in this condition radiological findings rarely correspond to functional impairment, we elected to quantify in a large cohort of acromegalic patients: the degree of motor disability compared with data from general population, the impact of joint involvement on quality of life and work productivity, and to look for associated factors.

METHODS

In 211 acromegalic patients, 131 with controlled disease and 80 with active disease, eight validated scales were used to evaluate the (i) prevalence and distribution of arthropathy, (ii) degree of motor disability and joint symptoms (VAS, AIMS symptoms and WOMAC), (iii) quality of life (AcroQoL and PASQ) and work capability (WPAI:GH) as consequences of joint complications.

RESULTS

Using the WOMAC questionnaire, for which population based normative values are available, a significantly higher prevalence and severity of motor disability was detected in acromegalics compared to the general population from literature. The results provided by the different questionnaires turned out to be highly concordant. All measures of motor disability correlated both with impaired quality of life and motor disability and were worse in females and in patients with higher BMI.

CONCLUSIONS

The questionnaires VAS, AIMS symptoms, and WOMAC (this latter both as a whole and with its functionality subscale), with their scores, proved to be the most adequate tools to evaluate motor disability and its consequences on both quality of life and work productivity in acromegaly. Female gender and higher BMI are associated with worse articular symptoms.

Acromegaly is associated with increased cancer risk: a survey in Italy

It is debated if acromegalic patients have an increased risk to develop malignancies. The aim of the present study was to assess the standardized incidence ratios (SIRs) of different types of cancer in acromegaly on a large series of acromegalic patients managed in the somatostatin analogs era. It was evaluated the incidence of cancer in an Italian nationwide multicenter cohort study of 1512 acromegalic patients, 624 men and 888 women, mean age at diagnosis 45 ± 13 years, followed up for a mean of 10 years (12573 person-years) in respect to the general Italian population. Cancer was diagnosed in 124 patients, 72 women and 52 men. The SIRs for all cancers was significantly increased compared to the general Italian population (expected: 88, SIR 1.41; 95% CI, 1.18-1.68, P < 0.001). In the whole series, we found a significantly increased incidence of colorectal cancer (SIR 1.67; 95% CI, 1.07-2.58, P = 0.022), kidney cancer (SIR 2.87; 95% CI, 1.55-5.34, P < 0.001) and thyroid cancer (SIR 3.99; 95% CI, 2.32-6.87, P < 0.001). The exclusion of 11 cancers occurring before diagnosis of acromegaly (all in women) did not change remarkably the study outcome. In multivariate analysis, the factors significantly associated with an increased risk of malignancy were age and family history of cancer, with a non-significant trend for the estimated duration of acromegaly before diagnosis. In conclusion, we found evidence that acromegaly in Italy is associated with a moderate increase in cancer risk.

Decreased adrenergic tone in acromegaly: evidence from direct recording of muscle sympathetic nerve activity

OBJECTIVE

Sympathovagal imbalance has been shown in acromegaly by indirect measurements of adrenergic tone. Data regarding direct measurement of sympathetic activity are lacking as yet. Aim of this study was to assess the adrenergic tone through direct recording of muscle sympathetic nerve activity (MSNA) in acromegalic patients.

DESIGN

Fifteen patients (age 26-66 years, eight women) with newly diagnosed active acromegaly without hyperprolactinaemia, pituitary hormone deficiencies, obstructive sleep apnoea and cardiac hypertrophy, and 15 healthy subjects matched for age, sex and body mass index were recruited. After evaluating anthropometric and echocardiographic parameters, anterior pituitary function, glucose and lipid metabolism, and measuring plasma leptin, direct recording of sympathetic outflow via the microneurographic technique was performed.

RESULTS

For similar anthropometric and metabolic parameters in patients and controls, HOMA index was significantly increased in the former (4·2 ± 2·39 vs 1·6 ± 0·19, P < 0·001). Surprisingly, this finding of insulin resistance was accompanied by a marked sympathetic inhibition (MSNA 18·3 ± 8·10 vs 37·3 ± 6·48 bursts/min, P < 0·0001, respectively in patients and controls). A reduction in plasma leptin (1·6 ± 1·04 vs 6·5 ± 2·01 μg/l, P < 0·0001) was also recorded in the patients. MSNA was positively correlated with leptin (P < 0·0001).

CONCLUSIONS

Newly diagnosed acromegalic patients without cardiac hypertrophy display a decreased sympathetic outflow in spite of insulin resistance. This finding might be related to hypoleptinaemia.

Assessment of biochemical control of acromegaly during treatment with somatostatin analogues by oral glucose load and insulin-like growth factor I

BACKGROUND

The use of oral glucose tolerance test (OGTT) in evaluating biochemical control in acromegalic patients on somatostatin analogues (SSA) has recently been questioned.

AIM

To gain further insights into this topic, we analyzed basal and nadir GH levels during OGTT in acromegalic patients on SSA.

SUBJECTS AND METHODS

Basal IGF-I and GH values, as well as GH levels along the test, were analyzed in 115 standard OGTT performed in 33 acromegalic patients followed up between 1993 and 2009. All patients were on SSA at the time of the study; 22 of them had previously undergone unsuccessful surgery. No patient had undergone radiotherapy. GH suppression was considered normal when the hormonal value fell to <1 μg/l during OGTT. Diagnostic accuracy was analyzed by receiver operating characteristic (ROC) curves.

RESULTS

ROC analysis showed that the GH basal value yielding the best specificity (100%) was 3.9 μg/l. All patients with basal GH>3.9 μg/l displayed lack of GH suppression after OGTT and 80% also displayed high IGF-I. Conversely, patients with basal GH<3.9 μg/l presented a variable biochemical pattern with half of them failing to suppress GH after OGTT and 36.6% displaying high IGF-I levels.

CONCLUSIONS

Our results show that baseline GH levels >3.9 μg/l are predictive of absent OGTT-dependent GH suppression; however, 20% of these patients display partial biochemical control (normal IGF-I levels). On the other hand, basal GH values <3.9 μg/l are not predictive of GH suppressibility by glucose and are often discordant with IGF-I levels.

The diagnosis of GH deficiency in obese patients: a reappraisal with GHRH plus arginine testing after pharmacological blockade of lipolysis

BACKGROUND

The diagnosis of GH deficiency (GHD) in obese patients is complicated by the reduced GH secretion associated with overweight. A GH response to GHRH+arginine lower than 4.2 microg/l is currently considered indicative of GHD in obesity. The aim of the study was to investigate the effect of acute pharmacological blockade of lipolysis on the GH response to GHRH+arginine in obese patients.

PATIENTS AND METHODS

Two groups of patients were studied: 12 obese patients with proven GHD and 14 patients with essential obesity. On separate occasions, two tests were carried out in each patient: GHRH+arginine and GHRH+arginine preceded by acipimox.

RESULTS

The mean GH peak after GHRH+arginine was significantly lower in hypopituitary patients than in subjects with essential obesity. Acipimox significantly increased the mean GH response in patients with essential obesity, but not in hypopituitary subjects. All hypopituitary patients and 7/14 patients with essential obesity displayed GH peaks lower than 4.2 microg/l after GHRH+arginine: the GH response to the test increased after acipimox pretreatment in five of these seven essentially obese subjects. After acipimox administration, free fatty acids (FFAs) significantly fell in both groups with comparable mean absolute decreases. All IGF1 values were normal in both groups of subjects.

CONCLUSIONS

Our study has demonstrated that the acipimox-induced acute reduction of circulating FFA levels increases mean somatotropin response to GHRH+arginine in patients with essential obesity, whereas it has no effect in hypopituitary subjects. The current criterion for the diagnosis of GHD in obese patients may be misleading. Indeed, subjects affected by third degree obesity, like most of our patients, may be erroneously classified as really GH-deficient and started on an expensive unjustified treatment. It appears therefore that the current criteria for the diagnosis of GHD in obesity should be reconsidered in the light of further studies also taking into account different body mass index groups.

Effects of treatment with somatostatin analogues on QT interval duration in acromegalic patients

OBJECTIVE

Cardiovascular disease is a major contributor to the increased mortality of acromegalic patients. Prolongation of the QT interval is considered an established risk factor for potentially fatal cardiac arrhythmias, an event frequently observed in acromegaly. Changes in ventricular repolarization have been observed with the use of octreotide, one of the somatostatin analogues (SSA) currently used for the medical treatment of this disease. Furthermore, octreotide is listed among the drugs able to prolong the QT interval. Thus, we elected to study the effects of long-term SSA administration on QT duration and left ventricular mass (LVM) in a group of acromegalic patients.

DESIGN AND PATIENTS

In a retrospective study, 30 acromegalic patients (19 women and 11 men, aged 25-77 years) were studied under basal conditions; 24 of them (15 women and nine men, aged 25-77 years) were studied again after 3-63 months of treatment (median 18 months) with SSA. Twenty-four healthy volunteers served as controls.

MEASUREMENTS

Patients and controls underwent electrocardiographic (ECG) analysis, and QT interval duration corrected for heart rate (QTc) was established according to the Bazett formula. In 17 of the SSA-treated patients, M- and B-mode echocardiography for the assessment of LVM index (LVMi) was performed.

RESULTS

Baseline QTc was significantly longer in patients than in controls. SSA administration was followed by a significant decrease in QTc, which reached a mean value similar to that measured in the controls. In particular, treatment with SSA normalized QTc in three out of the six patients with abnormally elevated values at baseline. After treatment, a significant reduction in heart rate was recorded, while LVMi displayed a slight but not significant decrease.

CONCLUSIONS

Acromegalic patients frequently display an abnormally prolonged QT interval, a known risk factor for potentially fatal arrhythmias. Treatment of these patients with SSA is able to improve and even normalize this alteration, probably contributing to the beneficial effects of these drugs on cardiac rhythm in this endocrine disorder. The inclusion of octreotide in the list of drugs that may increase QTc should be reconsidered as regards its indication in acromegaly.

Increased lipid peroxidation in adult GH-deficient patients: effects of short-term GH administration

OBJECTIVE

Adult GH deficiency (GHD) syndrome is characterized by increased risk of atherosclerosis and hence of cardio- and cerebrovascular mortality. Oxidative stress appears to play an important role in early atherogenesis. Oxidized LDL represents an important predictor of cardiovascular risk and is mainly responsible for oxidative damage of the endothelium. Its concentrations are increased in GHD, but the association between this abnormality and oxidative stress is still unclear, due to the discordant results yielded by the few available studies.

DESIGN AND METHODS

In 13 GHD patients, plasma lipid peroxide concentrations were measured before and after a 4-month treatment with recombinant human GH (rhGH) and compared with those of 13 age- and sex-matched controls. In the same subjects, the so-called "lag-time", an index of anti-oxidant activity and thus of plasma oxidative balance, was also measured using a fluorescence kinetics method.

RESULTS

Before treatment, peroxide levels were significantly higher in patients than in controls (374.0+/-31.52 vs 268.0+/-8.51 U.C., p<0.01), whereas the lag-time was significantly lower (113.0+/-10.70 vs 168.0+/-7.80 min, p<0.01). RhGH administration to patients resulted both in a significant decrease in lipid peroxide levels (from 374.0+/-31.52 to 336.0+/-33.17 U.C., p<0.01) and a significant prolongation of lag-time (from 113.0+/-10.70 to 144.0+/-15.00 min, p<0.01). After treatment, both parameters were no longer significantly different in patients and controls. Lag-time and peroxide levels at baseline did not show any correlation with IGF-I concentrations in GHD patients. After replacement therapy, however, lag-time was positively (r2= 0.62, p<0.01), and peroxide levels negatively (r2=0.41, p<0.05), correlated with IGF-I levels.

CONCLUSIONS

These data support the view that adult GHD syndrome is characterized by an unbalance between pro- and anti-oxidant factors with marked preponderance of the former. This abnormality, likely contributing to the increased atherogenic risk of GHD patients, is corrected by short-term GH administration at a dose able to increase, although not to fully normalize, IGF-I levels.

Isolated corticotrophin deficiency presenting with pericardial effusion

Isolated ACTH deficiency is a rare disorder often presenting with long-standing aspecific symptoms combined with unusual clinical presentations. We here describe a patient in whom pericardial effusion was part of the dinical presentation and fully resolved on steroid at replacement dosage, highlighting the possibility of hypoadrenalism as an additional cause of pericardial effusion of unknown origin.

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.

Markers of activation of coagulation and fibrinolysis in patients with Cushing's syndrome

Patients with active Cushing's syndrome have an increased thrombotic tendency. We chose to reassess the mechanism underlying the thrombophilic state associated with this clinical condition using sensitive markers of coagulation and fibrinolysis activation in 17 patients with active disease. The results were compared with those obtained in 12 Cushing's patients successfully treated by surgery and in 20 normal individuals. The general pattern of results in patients with active disease was the finding of increased levels of von Willebrand factor (VWF: Ag), a marker of enhanced metabolic function of endothelial cells (VWF:Ag 181 +/- 42 vs 110 +/- 43, p<0.001 in normal subjects), accompanied by signs of heightened thrombin and plasmin generation, expressed by high levels of thrombin-antithrombin (TAT 5.59+/-3.6 vs 3.06+/-0.92 ng/ml in controls, p<0.01) and plasmin-antiplasmin complexes (PAP 407+/-176 vs 245+/-67 ng/ml in controls, p<0.01). VWF:Ag and TAT values were significantly higher in hypertensive than in normotensive patients with active disease (205+/-40 vs 155+/-26 U/dl, p<0.05 and 7.49+/-3.7 vs 3.45+/-1.8, p<0.01, respectively). Plasma levels of plasminogen activator inhibitor type 1 were higher, though not to a statistically significant extent, in patients with active disease compared to controls (12.8+/-12.3 vs 5.6+/-7.4 IU/ml, NS) and positively correlated with body mass index (r=0.66, p<0.01). After surgical control of Cushing's syndrome, there was a partial or complete reversal of the abnormalities to values similar to those found in normal individuals. Our data suggest that the thrombophilic state present in patients with active Cushing's syndrome is related to an enhanced metabolic function of endothelial cells; this in turn may be caused by an heightened production of thrombin with secondary hyperfibrinolysis. Primary prophylaxis with anticoagulants is recommended in these patients when they are exposed to a thrombophilic condition such as surgery.

Influence of insulin on beta-endorphin plasma levels in obese and normal weight subjects

OBJECTIVE

To establish the possible role of hyperinsulinemia in the elevation of plasma beta-endorphin (beta-EP) levels observed in obese patients after an oral glucose load.

DESIGN

Oral glucose tolerance test (OGTT) and euglycemic-hyperinsulinemic clamp.

SUBJECTS

Two groups of six (age: 22-39 y, BMI: 30-48 kg/m2) and eight obese men (age: 18-37 y, BMI: 35-45 kg/m2), respectively, and five normal weight healthy men (age: 22-30 y, BMI 22-23 kg/m2).

MEASUREMENTS

Glucose, insulin and beta-EP levels at baseline and every 30 min until 180 min during the OGTT; glucose, insulin, C-peptide and beta-EP concentrations at baseline and in steady state condition (i.e. during the last 30 min of insulin infusion) in the euglycemic-hyperinsulinemic clamp studies.

RESULTS

In the six obese patients undergoing the OGTT a significant elevation of beta-EP plasma levels was observed between 60 and 90 min after glucose ingestion. In the clamp studies no significant differences in beta-EP plasma levels, blood glucose and serum insulin were observed between obese and normal weight subjects both at baseline and at steady state. A markedly diminished insulin sensitivity along with a lower inhibition of C-peptide during insulin infusion was observed in obese patients compared to control subjects.

CONCLUSION

A rise in serum insulin levels unaccompanied by a concomitant increase in blood glucose concentration is unable to elicit a beta-EP response in obese patients.