Acquired hypothalamic obesity: A clinical overview and update

Hypothalamic obesity (HO) is a rare and complex disorder that confers substantial morbidity and excess mortality. HO is a unique subtype of obesity characterized by impairment in the key brain pathways that regulate energy intake and expenditure, autonomic nervous system function, and peripheral hormonal signalling. HO often occurs in the context of hypothalamic syndrome, a constellation of symptoms that follow from disruption of hypothalamic functions, for example, temperature regulation, sleep-wake circadian control, and energy balance. Genetic forms of HO, including the monogenic obesity syndromes, often impact central leptin-melanocortin pathways. Acquired forms of HO occur as a result of tumours impacting the hypothalamus, such as craniopharyngioma, surgery or radiation to treat those tumours, or other forms of hypothalamic damage, such as brain injury impacting the region. Risk for severe obesity following hypothalamic injury is increased with larger extent of hypothalamic damage or lesions that contain the medial and posterior hypothalamic nuclei that support melanocortin signalling pathways. Structural damage in these hypothalamic nuclei often leads to hyperphagia, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue, the collective effect of which is rapid weight gain. Individuals with hyperphagia are perpetually hungry. They do not experience fullness at the end of a meal, nor do they feel satiated after meals, leading them to consume larger and more frequent meals. To date, most efforts to treat HO have been disappointing and met with limited, if any, long-term success. However, new treatments based on the distinct pathophysiology of disturbed energy homeostasis in acquired HO may hold promise for the future.

Impact of exenatide on weight loss and eating behavior in adults with craniopharyngioma-related obesity: the CRANIOEXE randomized placebo-controlled trial

IMPORTANCE

A major issue in the management of craniopharyngioma-related obesity (CRO) is the ineffectiveness of the current therapeutic approaches.

OBJECTIVE

To study the efficacy of glucagon-like peptide-1 analogs compared with placebo in adults with obesity CRO.

DESIGN

A double-blind multicenter superiority randomized clinical in trial in two parallel arms.

SETTING

Eleven French University Hospital Centers.

PARTICIPANTS

Adults with CRO (body mass index > 30 kg/m²) without the sign of recurrence of craniopharyngioma in the past year.

INTERVENTIONS

Exenatide or placebo injected subcutaneously twice a day during 26 weeks.

MAIN OUTCOMES AND MEASURES

The primary outcome was the mean change in body weight at week 26 in the intention-to-treat population. Secondary outcomes were eating behavior, calories intake, energy expenditure, cardiovascular, metabolic risk factor, quality of life, and the tolerance profile.

RESULTS

At week 26, weight decreased from baseline by a mean of -3.8 (SD 4.3) kg for exenatide and -1.6 (3.8) kg for placebo. The adjusted mean treatment difference was -3.1 kg (95% confidence interval [CI] -7.0 to 0.7, P = 0.11). Results were compatible with a higher reduction of hunger score with exenatide compared with placebo (estimated treatment difference in change from baseline to week 26: -2.3, 95% CI -4.5 to -0.2), while all other outcomes did not significantly differ between groups. Adverse events were more common with exenatide versus placebo, and occurred in, respectively, 19 (95%) participants (108 events) and 14 (70%) participants (54 events).

CONCLUSIONS AND RELEVANCE

Combined with intensive lifestyle interventions, a 26-week treatment with exenatide was not demonstrated superior to placebo to treat craniopharyngioma-related obesity.

Infantile Hypothalamic Hamartoma: A Rare Presentation of Isolated Obesity

Hypothalamic hamartomas (HHs) are rare, benign brain tumors or lesions of the hypothalamus that are predominantly identified in cases of epilepsy and central precocious puberty (CPP), whereas isolated manifestations of infantile obesity are atypical. We herein report an 8-month-old boy with severe obesity (Kaup index 26.4 [>100th percentile]) and uncontrollable hyperphagia. His growth chart demonstrated remarkable weight gain that exceeded the length gain in magnitude. Brain magnetic resonance imaging identified a lesion consistent with HH. There were no episodes or clinical findings of epilepsy, CPP, or Cushing disease. Hypothalamic obesity should be considered in the diagnosis even in infants with excessive weight gain due to overeating.

The role of glucagon-like peptide 1 receptor agonists for weight control in individuals with acquired hypothalamic obesity-A systematic review

Hypothalamic obesity does not respond well to conventional interventions for obesity. GLP-1 receptor agonists have mechanisms independent of the hypothalamus which may be potentially beneficial for managing hypothalamic obesity. This systematic review summarizes the efficacy and safety of GLP-1 receptor agonists use in hypothalamic obesity. A PRISMA-compliant systematic review was performed. Data was extracted from included studies and analysed based on change in weight, body mass index, glycaemic control, satiety, and safety profile with GLP-1 receptor agonist use. Ten studies comprising 5 case reports, 4 case series and 1 randomized-controlled trial included 54 patients (24 males, 30 females) with mean age of 25.2 (range 13-71) years with hypothalamic obesity who had received GLP-1 receptor agonists (exenatide = 48, liraglutide = 5 and dulaglutide = 1) over a mean duration of treatment of 12 (range 3-51) months. Mean weight reduction of 7.4 (SD 7.92) kg was observed in patients in whom weight was reported, with 85.7% of patients experiencing weight loss. All patients on liraglutide had weight reduction post-therapy. The sole trial had reported a non-significant reduction in BMI post-exenatide. Glycaemic control had either improved/maintained in all patients in whom this was measured. The main side effects of GLP-1 receptor agonist in individuals with hypothalamic obesity were nausea and vomiting; there were no major safety concerns. Based on limited published experience, GLP-1RA may be effective and safe for weight control in hypothalamic obesity, with the added benefit of improved glycaemic control in those with concurrent diabetes mellitus.

Could setmelanotide be the game-changer for acquired hypothalamic obesity?

Children with acquired hypothalamic obesity, e.g. following treatment for pediatric craniopharyngioma are at great risk for metabolic syndrome, cardiovascular health problems and premature mortality. Treatment for acquired hypothalamic obesity has thus far been disappointing. Several interventions were reported to be partially successful, including dextro-amphetamine and GLP-1R agonists, although results in acquired hypothalamic obesity are conflicting. Disruption of signaling through the melanocortin-4 receptor (MC4R) pathway results in hyperphagia and severe early-onset hypothalamic obesity. Recently, the MC4R agonist setmelanotide has shown promising results in children with genetic forms of hypothalamic obesity; POMC, PCSK1 and LEPR. Patient quotes such as "we have our family life back" illustrate the magnitude of the effect. Targeted hormone replacement therapy with a MC4R agonist for acquired hypothalamic obesity could be a game-changer. Preliminary results of setmelanotide treatment in 14, mostly pediatric, patients with acquired hypothalamic obesity are promising. The FDA has recommended that a prospective, randomized, blinded trial be conducted over a 12 months treatment period, comparable to pivotal trials for other obesity drugs. It may be discussed whether setmelanotide should be regarded as an obesity drug or whether it may be envisioned as an agent for hypothalamic substitution therapy. In this commentary we discuss the trial that is currently recruiting patients with acquired hypothalamic obesity.

Treatment and outcome of the Dutch Childhood Craniopharyngioma Cohort study: First results after centralization of care

BACKGROUND

Childhood craniopharyngioma (cCP) has excellent survival, but quality of life may be severely hampered by hypothalamic dysfunction. We aimed to evaluate treatment and hypothalamic outcomes of a Dutch cCP cohort, and evaluate the effect of centralization of care.

METHODS

A retrospective cohort study was performed, including cCP patients diagnosed between 2004 and 2021. Treatment characteristics and hypothalamic outcomes were evaluated and compared before and since centralization of care in May 2018.

RESULTS

We included 87 cCP patients. Cyst drainage/fenestration was performed in 29.9%, limited resection in 27.6%, near-total resection in 16.1%, and gross total resection (GTR) in 25.4%. Radiotherapy was given in 46.0%. After a median follow-up of 6.5 years, hypothalamic obesity (HO) was present in 24.7% and panhypopituitarism with diabetes insipidus in 71.3%. Higher body mass index (BMI) SDS at diagnosis and Muller grade II at last magnetic resonance imaging of follow-up were associated with overweight/obesity. No association was found between extensiveness of resection and overweight/obesity at last follow-up. When comparing before and after centralization of care, rates of GTR remained similar, but BMI outcomes changed; mean ΔBMI SDS 1 year after diagnosis from 1.12 (SD 1.15) to 0.81 (SD 1.24), and HO after 1 year decreased from 33.3% to 12.0% (P = .067), and after 2 years from 28.6% to 6.7% (P = NS).

CONCLUSIONS

In our nationwide cohort, GTR was performed in a relatively low percentage of patients and extensiveness of resection was no longer associated with HO at follow-up. A trend toward improvement of BMI is observed since centralization of care, which needs further exploration.

Overweight and obesity in children and adolescents with endocrine disorders

Obesity has become a serious medical condition where many factors can contribute to excess weight gain. The most common type of childhood obesity is simple obesity, which is due to gene-obesogenic environment interaction. Only a minority are due to pathological causes. Secondary causes of obesity, while less common, include these: genetic syndromes, drug-related obesity, as well as endocrine disorders (hypothyroidism, Cushing's syndrome, growth hormone deficiency, hypogonadism, pseudohypoparathyroidism type Ia, insulinoma, hypothalamic obesity and polycystic ovary syndrome). Given that some conditions may be treatable, physicians must be aware of obesity due to endocrinopathies and distinguish them from simple obesity, and treat them properly. Although rare among children, early detection of the endocrine cause of obesity leads to reduced morbidity and, in some cases, reduced mortality in these individuals. The aim of this review is to summarize the current findings on obesity-related endocrinopathies in children (illustrated by clinical examples), highlighting aspects of pathogenetic mechanisms, genetics, the clinical diagnosis, growth, body mass index and possible therapeutic approaches. Early detection and correction of endocrine obesity is of paramount importance for obese children who could benefit from timely diagnosis and an improved management of obesity as many disturbances related to obesity can be reversed at the early stage, if weight loss is achieved.

Blood Lipid Disorders in Post-Operative Craniopharyngioma Children and Adolescents and the Improvement with Recombinant Human Growth Hormone Replacement

Context

The high prevalence of hypothalamic obesity (HO) and dyslipidemia in individuals with craniopharyngioma (CP) following surgery is a cause for increasing concern. However, few studies have explored the lipid profile in pediatric CP patients, with inconsistent findings. In addition, the role of recombinant human growth hormone (rhGH) replacement remains unclear in these patients.

Objective

To compare the blood lipid profile among post-operative craniopharyngioma children and adolescents with that among healthy controls and to reveal the effects of rhGH replacement.

Methods

Data of 79 post-operative craniopharyngioma children and adolescents in our center were retrospectively collected. Sixty patients underwent rhGH replacement during the follow-ups. We selected 36 patients who received rhGH replacement therapy, while 20 patients received rhGH replacement for at least 1 year and had complete lipid data before and after treatment and compared them with 19 patients who did not receive rhGH replacement therapy.

Results

Craniopharyngioma patients had higher total cholesterol (TC) (5.17 vs 3.77 mmol/L), triglyceride (TG) (1.51 vs 0.73 mmol/L), and low-density lipoprotein cholesterol (LDL-C) (3.14 vs 2.10 mmol/L), and lower high-density lipoprotein cholesterol (HDL-C) (1.06 vs 1.39 mmol/L) than controls (all p < 0.001). The lipid profile of obese and non-obese patients was not significantly different. After rhGH replacement, TC was 0.90 mmol/L lower (p = 0.002) and LDL-C was 0.73 mmol/L lower (p = 0.010) than baseline. Although the baseline LDL-C was higher, patients with rhGH replacement had lower LDL-C (-0.73 mmol/L adjusted for age and sex, p = 0.045) after the initiation of replacement compared with patients without rhGH replacement.

Conclusion

The lipid profile of obese and non-obese children and adolescents with craniopharyngioma was unfavorable, and rhGH replacement could improve their lipid profile.

Craniopharyngioma-An update on metabolic and cognitive complications and new therapy

Craniopharyngiomas (CPs) are rare primary brain epithelial tumors arising in the suprasellar region from remnants of Rathke's pouch. About 50% originate at the level of the third ventricle floor, including the hypothalamus (HT). CPs are characterized by a low proliferation rate and symptoms due to mass effect and local infiltration and are managed primarily with surgery and radiotherapy. Gross total removal of a CP will reduce the recurrence rate but increases the risk of HT damage. Today, subtotal resection is the goal and will reduce the risk of HT damage. There are two histological subtypes of CP-adamantinomatous (ACP) and papillary CP (PCP)-that differ in their genesis and age distribution. ACPs are driven by somatic mutations in CTNNB1 gene (encoding β-catenin), and PCPs frequently harbor somatic BRAF V600E mutations. There are also two phenotypes of outcome, the one with a rather good outcome without HT damage and the other with HT damage where recurrent operation with additional cranial radiotherapy results in HT obesity (HO), affecting psychosocial life and cognitive dysfunction. The group with HO suffers from metabolic syndrome, lower basal metabolic rate, and leptin and insulin resistances. There is currently no successful treatment for HO. The group with HT damage suffers from cognitive dysfunction with attention deficits, impaired episodic memory, and processing speed. Diffusion tensor imaging has shown significant microstructural white matter alteration in several areas important for cognition. Recently, complete or partial tumor response was shown to targeted therapy, with BRAF and Mekinist inhibitors for PCPs with BRAF V600E mutation.

Semaglutide for Treating Obesity Induced by Craniopharyngioma Resection: A Successful Case Study

Surgical treatment of craniopharyngioma often leads to a rapid and dramatic weight gain, leading to hypothalamic obesity. Treatment focused on the diet, physical activity, and different types of drugs have very often provided unsatisfactory results. To date, no data have been reported on hypothalamic obesity (HO) regarding the use of semaglutide, a novel type 1 receptor glucagon-like peptide-1 agonist, to limit body weight gain after surgical removal of a neoplasm, despite its already documented efficacy in obesity treatment. In this case report, we tested semaglutide in an 18-year-old patient with HO induced by a surgical intervention for craniopharyngioma. A very favorable treatment response was found in terms of body weight reduction and improvement in metabolic parameters. Our patient lost more than than 30 kg after only 6 months of therapy, which has never been reported before in the literature on HO.

Approach to the Patient With Hypothalamic Obesity

Hypothalamic obesity (HO) is defined as abnormal weight gain due to physical destruction of the hypothalamus. Suprasellar tumors, most commonly craniopharyngiomas, are a classic cause of HO. HO often goes unnoticed initially as patients, families, and medical teams are focused on oncologic treatments and management of panhypopituitarism. HO is characterized by rapid weight gain in the first year after hypothalamic destruction followed by refractory obesity due to an energy imbalance of decreased energy expenditure without decreased food intake. Currently available pharmacotherapies are less effective in HO than in common obesity. While not a cure, dietary interventions, pharmacotherapy, and bariatric surgery can mitigate the effects of HO. Early recognition of HO is necessary to give an opportunity to intervene before substantial weight gain occurs. Our goal for this article is to review the pathophysiology of HO and to discuss available treatment options and future directions for prevention and treatment.

Obesity mechanism after hypothalamic damage: Cohort analysis of neuroimaging, psychological, cognitive, and clinical phenotyping data

OBJECTIVE

The hypothalamus regulates energy homeostasis, and its damage results in severe obesity. We aimed to investigate the multifaceted characteristics of hypothalamic obesity.

METHODS

We performed multidimensional analyses of brain structure/function and psychological and behavioral phenotypes in 29 patients with hypothalamic damage (HD) (craniopharyngioma) and 31 controls (non-functional pituitary adenoma). Patients underwent structural and functional magnetic resonance imaging and completed self-reports and cognitive tasks.

RESULTS

Patients with HD showed significantly higher postoperative weight gain than controls. The HD group also showed significant hypothalamic damage and lower neural activation in the left caudate nucleus in response to food images. The HD group had significantly higher food inattention, lower satiety, and higher restrained eating behavior. Within the HD group, higher restrained eating behavior was significantly associated with lower activation in the bilateral fusiform gyrus.

CONCLUSION

These results suggest that hypothalamic damage contributes to weight gain by altering the brain response, attention, satiety, and eating behaviors. The present study proposes novel neuro-psycho-behavioral mechanisms targeted for patients with hypothalamic obesity.

The clinical and metabolic characteristics of children and adolescents with hypothalamic dysfunction: A single-centre study from China

OBJECTIVE

Hypothalamic dysfunction is characterized by complex aetiologies, multiple forms of onset and various clinical symptoms. This study aims to explore the clinical and metabolic characteristics of hypothalamic dysfunction in Chinese children and adolescents.

DESIGN

This study is a single-centre, retrospective study that covers patients from 1989 to 2019.

PATIENTS

We included 40 children and adolescents with hypothalamic dysfunction from our medical centre in Beijing, China.

RESULTS

Intracranial tumour (37.5%) was the most common aetiology of children and adolescents with hypothalamic dysfunction, especially germ cell tumours, hypopituitarism (82.5%), weight gain (72.5%) and central diabetes insipidus (70.0%) were the most common symptoms in these patients. Furthermore, serum alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transpeptidase, uric acid, total cholesterol, triglycerides and low-density lipoprotein cholesterol was significantly higher in hypothalamic dysfunction patients than sex- and age-matched controls and sex, age and body mass index (BMI)-matched controls (all p < 0.05). However, albumin and high-density lipoprotein cholesterol were lower (p< 0.05). Moreover, 95% (38/40) of the patients had metabolic diseases. In addition, the incidence of dyslipidaemia and hyperuricemia in children and adolescents with hypothalamic dysfunction was significantly higher than both sex- and age-matched controls and sex-, age- and BMI-matched controls (both p < 0.05) as well.

CONCLUSIONS

Intracranial tumour was the most common aetiology in children and adolescents with hypothalamic dysfunction. In addition, these patients presented a worse metabolic profile on average than healthy patients.

Resting energy expenditure in children at risk of hypothalamic dysfunction

OBJECTIVE

Children with suprasellar brain damage are at risk of hypothalamic dysfunction (HD). HD may lead to decreased resting energy expenditure (REE). Decreased REE, however, is not present in all children with HD. Our aim was to assess which children suspect for HD have low REE, and its association with clinical severity of HD or radiological hypothalamic damage.

PATIENTS AND METHODS

A retrospective cohort study was performed. Measured REE (mREE) of children at risk of HD was compared to predicted REE (pREE). Low REE was defined as mREE <90% of predicted. The mREE/pREE quotient was associated to a clinical score for HD symptoms and to radiological hypothalamic damage.

RESULTS

In total, 67 children at risk of HD (96% brain tumor diagnosis) with a mean BMI SDS of +2.3 ± 1.0 were included. Of these, 45 (67.2%) had low mREE. Children with severe HD had a significant lower mean mREE/pREE quotient compared to children with no, mild, or moderate HD. Mean mREE/pREE quotient of children with posterior hypothalamic damage was significantly lower compared to children with no or anterior damage. Tumor progression or tumor recurrence, severe clinical HD, and panhypopituitarism with diabetes insipidus (DI) were significant risk factors for reduced REE.

CONCLUSION

REE may be lowered in children with hypothalamic damage and is associated to the degree of clinical HD. REE is, however, not lowered in all children suspect for HD. For children with mild or moderate clinical HD symptoms, REE measurements may be useful to distinguish between those who may benefit from obesity treatment that increases REE from those who would be better helped using other obesity interventions.

Management of Childhood-onset Craniopharyngioma in Italy: A Multicenter, 7-Year Follow-up Study of 145 Patients

CONTEXT

Nationwide data on children diagnosed with craniopharyngioma (CP) are not available in Italy.

OBJECTIVE

This work aimed to identify patients' characteristics, type of surgical approach, complications and recurrences, number of pituitary deficits, and number of patients starting growth hormone (GH) treatment.

METHODS

A retrospective multicenter collection took place of 145 patients aged 0 to 18 years who underwent surgery for CP between 2000 and 2018, and followed up in 17 Italian centers of pediatric endocrinology.

RESULTS

Age at diagnosis was 8.4 ± 4.1 years. Duration of symptoms was 10.8 ± 12.5 months and headache was most frequent (54%), followed by impaired growth (48%) and visual disturbances (44%). Most lesions were suprasellar (85%), and histology was adamantinomatous in all cases but two. Surgical approach was transcranial (TC) in 67.5% of cases and transsphenoidal (TS) in 31.%. The TC approach was prevalent in all age groups. Postsurgery complications occurred in 53% of cases, with water-electrolyte disturbances most frequent. Radiotherapy was used in 39% of cases. All patients but one presented with at least one hormone pituitary deficiency, with thyrotropin deficiency most frequent (98.3%), followed by adrenocorticotropin (96.8%), arginine vasopressin (91.1%), and GH (77.4%). Body mass index (BMI) significantly increased over time. A hypothalamic disturbance was present in 55% of cases. GH therapy was started during follow-up in 112 patients at a mean age of 10.6 years, and 54 developed a recurrence or regrowth of the residual lesion.

CONCLUSION

CP is often diagnosed late in Italy, with TC more frequent than the TS surgical approach. Postsurgery complications were not rare, and hypopituitarism developed almost in all cases. BMI shows a tendency to increase overtime.

A Survey of Patient-Relevant Outcomes in Pediatric Craniopharyngioma: Focus on Hypothalamic Obesity

CONTEXT

Individuals treated for pediatric craniopharyngioma, a rare, grade 1 brain tumor, frequently develop hypothalamic obesity, a complication often recalcitrant to intervention. Although hypothalamic obesity is known to adversely impact quality of life, less is known about how caregivers and patients experience this condition.

OBJECTIVE

Our goal was to examine the approaches that families take towards weight management and the impact on social function in individuals with craniopharyngioma and obesity. Individuals with craniopharyngioma without obesity were included as a comparison.

SUBJECTS AND METHODS

Adult caregivers of children <18y with craniopharyngioma completed a web-based survey posted by a patient advocacy organization between February and July 2020. Questions related to the child's diagnosis, medications, lifestyle modifications, and social function along with research priorities. Descriptive statistics were generated. Linear regression was used to assess the independent effects of obesity and other covariates on social function.

RESULTS

Of 106 respondents, 60 (57%) reported their child had obesity at the time of survey completion. In contrast, only 6 (5.7%) had obesity prior to craniopharyngioma diagnosis. A majority (92%) of those with obesity had tried limiting calories or carbohydrates; 31% and 69% found these helpful, respectively. Thirty-eight percent had tried weight loss medications (stimulants, metformin, GLP1R-agonists, and topiramate) and 48% found at least one helpful. Both stimulant and anti-depressant use were reported more frequently with obesity. An index (T-score) reflecting social function was lower in the cohort than a population reference, 41 (SD 11) vs. 50 (SD 10), p<0.001. In a linear model, both older age and obesity were independently associated with greater social impairment. Ninety-four percent of respondents caring for a child with obesity (and 79% of all respondents) identified "improving treatments and prevention for hypothalamic obesity" as a key research priority.

CONCLUSIONS

Only a minority of individuals with hypothalamic obesity had trialed medication, even though many reported that lifestyle modification was inadequate. Furthermore, social function was significantly impaired overall in survivors compared to a reference cohort, and even more so in individuals with obesity. These findings highlight the opportunity to improve social functioning as an additional potential benefit of improved treatments for hypothalamic obesity.

Transition From Diencephalic Syndrome to Hypothalamic Obesity in Children With Suprasellar Low Grade Glioma: A Case Series

BACKGROUND

Children with suprasellar low grade glioma (LGG) frequently develop problems to maintain their body weight within the normal range, due to hypothalamic dysfunction. Hypothalamic damage may result in the diencephalic syndrome (DS), characterized by underweight or failure to thrive, but also in hypothalamic obesity (HO). Children with LGG presenting with DS at young age often develop HO later in life. The underlying pathophysiology for this change in body mass index (BMI) is not understood. Previous hypotheses have focused on the tumor or its treatment as the underlying cause. To better understand its etiology, we aimed to relate changes in BMI over time in children with suprasellar LGG presenting with DS to age, tumor progression, treatment, and endocrine function. We hypothesize that the development of HO in children with LGG presenting with DS is related to maturation status of the hypothalamus at time of injury and thus age.

METHODS

In this retrospective case series, all cases diagnosed in the Netherlands with suprasellar located LGG, currently treated or followed, with a history of DS developing into HO were included.

RESULTS

In total, 10 children were included. Median age at LGG diagnosis was 1.5 years (range 0.4-5.5), median BMI SDS was -2.64. The children developed overweight at a median age of 4.5 years (2.2-9.8). The median total difference in BMI SDS between underweight and obesity was +5.75 SDS (4.5-8.7). No association could be found between transition of DS to HO and onset of a pituitary disorder (present in 70.0%), surgery, chemotherapy, or tumor behavior. Two had developed central precocious puberty (CPP), both while having underweight or normal weight.

CONCLUSION

The shift from DS to HO in children with hypothalamic LGG may be associated with age and not to tumor behavior, treatment characteristics or pituitary function. The development of CPP in these children seems not to be related to obesity. Our findings may indicate that the clinical picture of hypothalamic dysfunction reflects the maturation state of the hypothalamus at time of lesioning. Future prospective studies are needed to better understand underlying causative mechanisms of the morbid changes in body weight.

Dextroamphetamine Treatment in Children With Hypothalamic Obesity

INTRODUCTION

Hypothalamic obesity (HO) in children has severe health consequences. Lifestyle interventions are mostly insufficient and currently no drug treatment is approved for children with HO. Amphetamines are known for their stimulant side-effect on resting energy expenditure (REE) and suppressing of appetite. Earlier case series have shown positive effects of amphetamines on weight in children with acquired HO. We present our experiences with dextroamphetamine treatment in the, up to now, largest cohort of children with HO.

METHODS

A retrospective cohort evaluation was performed of children with HO treated with dextroamphetamine at two academic endocrine pediatric clinics. Off-label use of dextroamphetamine was initiated in patients with progressive, therapy-resistant acquired or congenital HO. Anthropometrics, REE, self-reported (hyperphagic) behavior and energy level, and side effects were assessed at start and during treatment.

RESULTS

Nineteen patients with a mean age of 12.3 ± 4.0 years had been treated with dextroamphetamine. In two patients, ΔBMI SDS could not be evaluated due to short treatment duration or the simultaneous start of extensive lifestyle treatment. Mean treatment duration of the 17 evaluated patients was 23.7 ± 12.7 months. Fourteen patients (n = 10 with acquired HO, n = 4 with congenital HO) responded by BMI decline or BMI stabilization (mean ΔBMI SDS of -0.6 ± 0.8, after a mean period of 22.4 ± 10.5 months). In three patients, BMI SDS increased (mean ΔBMI SDS of +0.5 ± 0.1, after a mean period of 29.7 ± 22.6 months). In 11 responders, measured REE divided by predicted REE increased with +8.9%. Thirteen patients (68.4%) reported decreased hyperphagia, improvement of energy level and/or behavior during treatment. Two patients developed hypertension during treatment, which resulted in dosage adjustment or discontinuation of treatment. Twelve children continued treatment at last moment of follow-up.

CONCLUSION

In addition to supportive lifestyle interventions, dextroamphetamine treatment may improve BMI in children with HO. Furthermore, dextroamphetamines have the potential to decrease hyperphagia and improve resting energy expenditure, behavior, and energy level. In patients with acquired HO, these effects seem to be more pronounced when compared to patients with congenital HO. Future studies are needed to support these results.

Treatment of Acquired Hypothalamic Obesity: Now and the Future

The hypothalamus is the centre of neuroendocrine regulation of energy homeostasis and appetite. Maldevelopment of, or damage to, the key hypothalamic nuclei disrupts the coordinated balance between energy intake and expenditure leading, to rapid and excessive weight gain. Hypothalamic obesity is compounded by a disruption of the hypothalamic-pituitary axis, sleep disruption, visual compromise, and neurological and vascular sequalae. Amongst suprasellar tumors, craniopharyngioma is the most common cause of acquired hypothalamic obesity, either directly or following surgical or radiotherapeutic intervention. At present, therapy is limited to strategies to manage obesity but with a modest and variable impact. Current approaches include optimizing pituitary hormone replacement, calorie restriction, increased energy expenditure through physical activity, behavioral interventions, pharmacotherapy and bariatric surgery. Current pharmacotherapeutic approaches include stimulants that increase energy consumption, anti-diabetic agents, hypothalamic-pituitary substitution therapy, octreotide, and methionine aminopeptidase 2 (MetAP2) inhibitors. Some pharmacological studies of hypothalamic obesity report weight loss or stabilization but reported intervention periods are short, and others report no effect. The impact of bariatric surgery on weight loss in hypothalamic obesity again is variable. Novel or combined approaches to manage hypothalamic obesity are thus required to achieve credible and sustained weight loss. Identifying etiological factors contributing hypothalamic obesity may lead to multi-faceted interventions targeting hyperphagia, insulin resistance, decreased energy expenditure, sleep disturbance, hypopituitarism and psychosocial morbidity. Placebo-controlled trials using current single, or combination therapies are required to determine the impact of therapeutic agents. A well-defined approach to defining the location of hypothalamic damage may support the use of future targeted therapies. Intranasal oxytocin is currently being investigated as an anorexogenic agent. Novel agents including those targeting pro-opimelanocortin-C and AgRP/NPY expressing neurons and the MC4 receptor may result in better outcomes. This article discusses the current challenges in the management of hypothalamic obesity in children and young people and future therapeutic approaches to increasing weight loss and quality of life in these patients.

Metabolic syndrome as a common comorbidity in adults with hypothalamic dysfunction

OBJECTIVE

Hypothalamic dysfunction (HD) results in various endocrine disorders and is associated with an increased risk of metabolic comorbidities. This study aimed to analyze the clinical characteristics and metabolic abnormalities of adults with HD of various causes.

METHODS

This study retrospectively reviewed adults with HD treated at our center between August 1989 and October 2020. Metabolic characteristics of patients were compared to those of age-, sex-matched lean, and body mass index (BMI)-matched controls.

RESULTS

Temperature dysregulation (61.0%) was the most common hypothalamic physiological dysfunction. At least one anterior pituitary hormone deficiency was observed in 50 patients (84.7%), with hypogonadotropic hypogonadism being the most frequently observed. Metabolic syndrome was confirmed in 31 patients (52.5%) and was significantly more prevalent in those with panhypopituitarism or overweight/obesity. Metabolic syndrome (MetS) was significantly more common in patients with HD than in both lean and BMI-matched controls (P < 0.001 and P = 0.030, respectively). Considering the components of MetS, elevated fasting glucose levels were significantly more common in patients with HD than in BMI-matched controls (P = 0.029). Overweight/obesity and panhypopituitarism were significant risk factors for MetS in the multivariate analysis on patients with HD. Moreover, in the multivariate analysis on patients and BMI-matched control, HD was a significant risk factor of MetS (P=0.035, OR 2.919) after adjusted for age, sex and BMI.

CONCLUSIONS

Temperature dysregulation and hypogonadotropic hypogonadism are the most common physiological and endocrine dysfunctions, respectively. MetS and unfavorable metabolic profiles were prevalent in adults with HD. HD was a significant risk factor of MetS after adjusted for BMI.

Rare genetic causes of obesity: diagnosis and management in clinical care

Rare genetic forms of obesity are linked to impaired energy balance (i.e., eating behaviour and energy expenditure) involving hypothalamic pathways. More than 60 genes coding for proteins located in the hypothalamic leptin/melanocortin pathway contribute to the development of these rare forms of obesity. The ambition of the French National Protocol for the Diagnosis and Care (PNDS) of Obesity of Rare Causes was to establish practical recommendations for assessment and management at all ages. This report is available on the website of the French Health Authority (HAS). In addition to severe obesity, patients often display obesity-related comorbidities and neuropsychological/psychiatric disorders. These complex conditions make clinical management particularly challenging. Early diagnosis is critical for the organization of coordinated specialized multidisciplinary care, with mandatory interaction between caregivers, social partners and families. Strategies to prevent aggravation of obesity consist in limiting access to food, establishing a reassuring daily eating environment, and the practice of sustained adapted supervised daily physical activity. The implementation of genetic diagnosis in clinical practice now enables a personalized medicine approach with access to new drug therapies, and improves the analysis of the risk/benefit ratio of bariatric surgery.

Bariatric Surgery for Hypothalamic Obesity in Craniopharyngioma Patients: A Retrospective, Matched Case-Control Study

CONTEXT

Craniopharyngioma is a sellar tumor associated with high rates of pituitary deficiencies (~ 98%) and hypothalamic obesity (~ 50%).

OBJECTIVE

This work aims to determine the efficacy regarding long-term weight loss after bariatric surgery in obese craniopharyngioma patients with hypothalamic dysfunction.

METHODS

This retrospective, case-control, multicenter, international study included obese craniopharyngioma patients (N = 16; of whom 12 are women) with a history of bariatric surgery (12 Roux-en-Y gastric bypass, 4 sleeve gastrectomy; median age 21 years [range, 15-52 years], median follow-up 5.2 years [range, 2.0-11.3 years]) and age/sex/surgery/body mass index-matched obese controls (N = 155). Weight loss and obesity-related comorbidities up to 5 years after bariatric surgery were compared and changes in hormonal replacement therapy evaluated.

RESULTS

Mean weight loss at 5-year follow-up was 22.0% (95% CI, 16.1%-27.8%) in patients vs 29.5% (95% CI, 28.0%-30.9%) in controls (P = .02), which was less after Roux-en-Y gastric bypass (22.7% [16.9%-28.5%] vs 32.0% [30.4%-33.6%]; P = .003) but at a similar level after sleeve gastrectomy (21.7% [-1.8% to 45.2%] vs 21.8% [18.2%-25.5%]; P = .96). No major changes in endocrine replacement therapy were observed after surgery. One patient died (unknown cause). One patient had long-term absorptive problems.

CONCLUSION

Obese patients with craniopharyngioma had a substantial mean weight loss of 22% at 5-year follow-up after bariatric surgery, independent of type of bariatric surgery procedure. Weight loss was lower than in obese controls after Roux-en-Y gastric bypass. Bariatric surgery appears to be effective and relatively safe in the treatment of obese craniopharyngioma patients.

Childhood-onset Craniopharyngioma

Craniopharyngiomas are rare embryonic malformational tumors of the sellar/parasellar region, classified by the World Health Organization (WHO) as tumors with low-grade malignancy (WHO I). The childhood adamantinomatous subtype of craniopharyngioma is usually cystic with calcified areas. At the time of diagnosis, hypothalamic/pituitary deficits, visual disturbances, and increased intracranial pressure are major symptoms. The treatment of choice in case of favorable tumor location (without hypothalamic involvement) is complete resection. It is important to ensure that optical and hypothalamic functionality are preserved. In case of unfavorable tumor location, that is with hypothalamic involvement, a hypothalamus-sparing surgical strategy with subsequent local irradiation of residual tumor is recommended. In the further course of the disease, recurrences and progression often occur. Nevertheless, overall survival rates are high at 92%. Severe impairment of quality of life and comorbidities such as metabolic syndrome, hypothalamic obesity, and neurological consequences can be observed in patients with disease- and/or treatment-related lesions of hypothalamic structures. Childhood-onset craniopharyngioma frequently manifests as a chronic disease so that patients require lifelong, continuous care by experienced multidisciplinary teams to manage clinical and quality of life consequences. For this review, a search for original articles and reviews published between 1986 and 2020 was performed in Pubmed, Science Citation Index Expanded, EMBASE, and Scopus. The search terms used were "craniopharyngioma, hypothalamus, pituitary obesity, irradiation, neurosurgery.

Risk Factors for Hypothalamic Obesity in Patients With Adult-Onset Craniopharyngioma: A Consecutive Series of 120 Cases

Context

Hypothalamic obesity (HO) is a severe complication following craniopharyngioma, but studies regarding the sequelae in adult-onset patients with craniopharyngioma are sparse.

Objective

The objective of the study was to describe weight changes after surgical treatment in adult-onset craniopharyngioma patients and to analyze risk factors for postoperative weight gain and HO.

Subjects and Method

A retrospective analysis was conducted of 120 adult-onset patients who underwent surgery for craniopharyngioma and follow-up at the institution of the authors between January 2018 and September 2020. Clinical characteristics, anthropometric data, image features, treatment modalities, and endocrine indices were collected. Multivariable logistic regression analysis was used to identify independent risk factors for postoperative weight gain and HO.

Results

Forty-nine (40.8%) patients had clinically meaningful weight gain (≥5%) in a median follow-up time of 12.0 months (range 1.0-41.0 months) after surgery. The mean postoperative weight gain in this subgroup was 17.59 ± 12.28 (%). Weight gain continued in the first year following surgery. Patients with lower preoperative BMI [OR 0.78, 95% CI (0.67-0.90), P = 0.001] and the adamantinomatous subtype [OR 3.46, 95% CI (1.02-11.76), P = 0.047] were more likely to experience postoperative weight gain ≥5%. The prevalence of HO was 19.2% preoperatively and increased to 29.2% at last follow-up postoperatively. Only preoperative BMI [OR 2.51, 95% CI (1.64-3.85), P < 0.001] was identified as an independent risk factor for postoperative HO.

Conclusions

HO is a common complication in patients with adult-onset craniopharyngioma. Patients with higher preoperative BMI had a greater risk for developing HO postoperatively.

The Vagus Nerve and Spleen: Influence on White Adipose Mass and Histology of Obese and Non-obese Rats

The vagus nerve (VN) and spleen represent a complex interface between neural and immunological functions, affecting both energy metabolism and white adipose tissue (WAT) content. Here, we evaluated whether vagal and splenic axis participates in WAT mass regulation in obese and non-obese male Wistar rats. High doses of monosodium glutamate (M; 4 g/Kg) were administered during the neonatal period to induce hypothalamic lesion and obesity (M-Obese rats). Non-obese or Control (CTL) rats received equimolar saline. At 60 days of life, M-Obese and CTL rats were randomly distributed into experimental subgroups according to the following surgical procedures: sham, subdiaphragmatic vagotomy (SV), splenectomy (SPL), and SV + SPL (n = 11 rats/group). At 150 days of life and after 12 h of fasting, rats were euthanized, blood was collected, and the plasma levels of glucose, triglycerides, cholesterol, insulin, and interleukin 10 (IL10) were analyzed. The visceral and subcutaneous WAT depots were excised, weighed, and histologically evaluated for number and size of adipocytes as well as IL10 protein expression. M-Obese rats showed higher adiposity, hyperinsulinemia, hypertriglyceridemia, and insulin resistance when compared with CTL groups (p < 0.05). In CTL and M-Obese rats, SV reduced body weight gain and triglycerides levels, diminishing adipocyte size without changes in IL10 expression in WAT (p< 0.05). The SV procedure resulted in high IL10 plasma levels in CTL rats, but not in the M-Obese group. The splenectomy prevented the SV anti-adiposity effects, as well as blocked the elevation of IL10 levels in plasma of CTL rats. In contrast, neither SV nor SPL surgeries modified the plasma levels of IL10 and IL10 protein expression in WAT from M-Obese rats. In conclusion, vagotomy promotes body weight and adiposity reduction, elevating IL10 plasma levels in non-obese animals, in a spleen-dependent manner. Under hypothalamic obesity conditions, VN ablation also reduces body weight gain and adiposity, improving insulin sensitivity without changes in IL10 protein expression in WAT or IL10 plasma levels, in a spleen-independent manner. Our findings indicate that the vagal-spleen axis influence the WAT mass in a health state, while this mechanism seems to be disturbed in hypothalamic obese animals.

Multidisciplinary Approach for Hypothalamic Obesity in Children and Adolescents: A Preliminary Study

Hypothalamic obesity (HO) is delineated by an inexorable weight gain in subjects with hypothalamic disorder (congenital or acquired). The aim of the present study was to evaluate the effect of a multidisciplinary approach on weight trend and metabolic outcome in children and adolescents with hypothalamic disease who were overweight or obese. Thirteen patients (aged 8.1–16.1 years) received a personalized diet, accelerometer-based activity monitoring, and psychological assessment. Height, weight, body mass index (BMI), and serum metabolic parameters were assessed at baseline (T0) and after six months (T1). Metformin was introduced at T1 in four subjects who were then re-evaluated after six months (T2). At T1, weight gain was significantly reduced compared with T0 (0.29 ± 0.79 kg/month vs. 0.84 ± 0.55 kg/month, p = 0.03), and weight standard deviation score (SDS) and BMI SDS did not change significantly, as serum metabolic parameters. The four subjects treated with metformin showed a reduction of weight SDS and BMI SDS at T2. In conclusion, patients treated with our multidisciplinary approach showed, after 6 months, favorable results characterized by decreased weight gain and stabilization of weight SDS and BMI SDS in a condition usually characterized by inexorable weight gain. However, further analysis, larger cohorts, and longer follow-up are needed to confirm these preliminary data.

Successful Diagnoses and Remarkable Metabolic Disorders in Patients With Solitary Hypothalamic Mass: A Case Series Report

BACKGROUND

Solitary intracranial hypothalamic mass occurs rarely. The etiological diagnosis of solitary hypothalamus lesion is challenging and often unachievable. Although previous studies indicated that lesions affecting the hypothalamus often cause significant metabolic disorders, few reports about the metabolic disturbances of patients with solitary hypothalamic mass have been reported.

METHOD

Twenty-five patients with solitary hypothalamus lesions who had been evaluated and treated in Huashan Hospital from January 2010 to December 2020 were retrospectively enrolled. The clinical manifestations, radiological features, endocrine and metabolic disorders, and pathology were analyzed.

RESULTS

The male to female ratio was 5/20. The median age of onset was 22 (19, 35) years old. The most common initial symptom was polydipsia/polyuria (19/25, 76.0%) and amenorrhea (9/20, 45.0%). A high prevalence of hypopituitarism of different axes was found, with almost all no less than 80%. Central hypogonadism (21/22, 95.5%) and central diabetes insipidus (19/21, 90.5%) were the top two pituitary dysfunctions. Conclusive diagnoses were achieved by intracranial surgical biopsy/resection or stereotactic biopsy in 16 cases and by examining extracranial lesions in 3 cases. The pathological results were various, and the most common diagnoses were Langerhans cell histiocytosis (7/19) and hypothalamitis (5/19). The mean timespan from onset to diagnosis in the 19 cases was 34 ± 26 months. Metabolic evaluations revealed remarkable metabolic disorders, including hyperlipidemia (13/16, 81.3%), hyperglycemia (10/16, 62.5%), hyperuricemia (12/20, 60%), overweight/obesity (13/20, 65.0%), and hepatic adipose infiltration (10/13, 76.6%).

CONCLUSION

Either surgical or stereotactic biopsy will be a reliable and relatively safe procedure to help to confirm the pathological diagnosis of solitary hypothalamic mass. Metabolic disorders were severe in patients with solitary hypothalamic mass. The management of such cases should cover both the treatment of the primary disease, as well as the endocrine and metabolic disorders.

Clinical Implication of Individually Tailored Segmentation Method for Distorted Hypothalamus in Craniopharyngioma

OBJECTIVE

Several attempts have been done to capture damaged hypothalamus (HT) using volumetric measurements to predict the development of hypothalamic obesity in patients with craniopharyngioma (CP). This study was to develop a novel method of HT volume measurement and examine the associations between postoperative HT volume and clinical parameters in patients with CP.

METHODS

We included 78 patients with adult-onset CP who underwent surgical resection. Postoperative HT volume was measured using T1- and T2-weighted magnetic resonance imaging (MRI) with a slice thickness of 3 mm, and corrected for temporal lobe volume. We collected data on pre- and postoperative body weights, which were measured at the time of HT volume measurements.

RESULTS

The corrected postoperative HT volume measured using T1- and T2-weighted images was significantly correlated (r=0.51 [95% confidence interval (CI) 0.32 to 0.67], P<0.01). However, HT volume was overestimated using T1-weighted images owing to obscured MR signal of the thalamus in patients with severe HT damage. Therefore, we used T2-weighted images to evaluate its clinical implications in 72 patients with available medical data. Postoperative HT volume was negatively associated with preoperative body weight and preoperative tumor volume (r=-0.25 [95% CI -0.45 to -0.04], P=0.04 and r=-0.26 [95% CI -0.40 to -0.15], P=0.03, respectively). In the subgroup analysis of CP patients who underwent primary surgery (n=56), pre- and postoperative body weights were negatively associated with HT volume (r=-0.30 [95% CI -0.53 to -0.03], P=0.03 and r=-0.29 [95% CI -0.53 to -0.02], P=0.03, respectively).

CONCLUSIONS

Adult-onset CP patients showed negative associations between postoperative HT volume and preoperative/postoperative body weight using a new method of HT volume measurement based on T2-weighted images.

Obstructive sleep apnea in children with hypothalamic obesity: Evaluation of possible related factors

INTRODUCTION

Hypothalamic obesity (HO) is a type of obesity that is caused by hypothalamic damage. HO can be complicated by obstructive sleep apnea syndrome (OSAS) due to anatomical narrowing of the upper airway and hypothalamic damage-induced dysfunction of the sleep control mechanisms. We aimed to explore the presence and severity of OSAS in children with HO and hypothesized that OSAS is more severe and frequent in HO than exogenous obesity (EO).

METHODS

This cross-sectional study was conducted among children aged 6.6-17.9 years. Subjects with HO (n = 14) and controls with EO (n = 19) were consecutively recruited through an endocrinology clinic. All patients underwent full-night polysomnography. The primary outcomes were obstructive apnea-hypopnea index (OAHI) and the severity of OSAS. We analyzed the polysomnography findings, biochemical parameters, Brodsky and modified Mallampati scores, and blood pressure compared with the controls. We explored the different obesity types and these variables in association with OAHI using multiple linear regression (MLR).

RESULTS

Age and body mass index z scores (BMI-z) were similar between the EO and HO groups. The OAHI of HO (5.8) was higher than that of EO (2.2). In MLR, the predicted OAHI was formulated as an equation using regression coefficients of obesity type (HO), age, and BMI-z (R²  = .41). In the logistic regression analysis, the odds ratio of moderate/severe OSA was 5.6 for HO.

CONCLUSIONS

Children with HO have a higher risk of moderate/severe OSAS than children with EO. Polysomnography should be considered in all patients with HO.

Metabolic features and changes in glucose-induced serum glucagon-like peptide-1 levels in children with hypothalamic obesity

Background Hypothalamic damage may alter glucagon-like peptide-1 (GLP-1) secretion and be involved in the pathogenesis of obesity. We aim to evaluate the metabolic features and the dynamic changes of GLP-1 levels during an oral glucose tolerance test (OGTT) in children with hypothalamic obesity (HO) compared with simple obesity controls. Methods Subjects included eight patients (six females, aged 9-16 years) with hypothalamo-pituitary tumors who later developed obesity and eight controls with simple obesity matched for age, body mass index (BMI), gender and puberty. We assessed the metabolic syndrome features, fat mass, severity of hyperphagia using a standardized questionnaire, and measured glucose, insulin and GLP-1 levels during a standard 75 g OGTT. Results Age, gender distribution, pubertal status and BMI-Z scores were not significantly different. Subjects with HO had higher fasting triglycerides (TG) than controls (128 vs. 94 mg/dL; p=0.05). Four HO subjects and three controls met the criteria for the metabolic syndrome. Fasting and 120 min post-glucose load GLP-1 levels were significantly higher in HO patients than in controls (21.9 vs. 19.7 pg/mL; p=0.025, 22.1 vs. 17.7 pg/mL; p=0.012). Patients with HO had significantly higher hyperphagia scores than in simple obese controls (13 vs. 2.5; p=0.012). Conclusions Patients with HO appear to have more metabolic complications and hyperphagia than controls with simple obesity. Impaired satiety may play an important role in HO. Fasting and glucose-induced serum GLP-1 concentrations seem to be altered in HO patients and could be a part of the pathogenesis of HO.

Laparoscopic Sleeve Gastrectomy on Severe Obesity after Intracranial Germinoma Treatment: A Case Report

Hypothalamic obesity is a clinical syndrome characterized by severe and refractory obesity that is caused by hypothalamic function impairment. Recently, bariatric surgery has been attempted for patients with hypothalamic obesity after craniopharyngioma, but experiences have not yet been accumulated in other hypothalamic disorders. Here, we report the case of a 39-year-old male patient with panhypopituitarism who received laparoscopic sleeve gastrectomy (LSG) after intracranial germinoma treatment. The patient was diagnosed with intracranial germinoma at age 15 and achieved complete remission after radiotherapy (total 50 Gy). He was obese during diagnosis [body mass index (BMI), 29.2 kg/m²], and his obesity gradually worsened after the intracranial germinoma treatment, and LSG was considered when his BMI was 48.6 kg/m². After 1 month of hospitalized diet-exercise program, LSG was performed. After LSG, his BMI gradually decreased and reached 38.8 kg/m² on the day of discharge (6 weeks after the surgery). Five months after LSG, his insulin resistance improved, but insulin hypersecretion remained. Fifteen months after the surgery, his BMI was 31.2 kg/m², with marked decrease in visceral and subcutaneous fat areas (from 393.8 cm² and 168.2 cm² before the surgery to 111.5 cm² and 56.3 cm², respectively.). To our knowledge, this is the first case of LSG for hypothalamic obesity after intracranial germinoma treatment. Although the pathophysiology of hypothalamic obesity is different from that of primary obesity, LSG could be a successful therapeutic choice for patients with hypothalamic obesity after the intracranial germinoma treatment.

Hypothalamic Obesity: 4 Years of the International Registry of Hypothalamic Obesity Disorders

OBJECTIVE

Hypothalamic obesity (HyOb) is a rare cause of rapid weight gain and early metabolic comorbidities. Effective treatment strategies are limited. The registry collected participant data and compared treatment approaches.

METHODS

The International Registry of Hypothalamic Obesity Disorders (IRHOD) was created as a registry portal to provide education. Data collected from the initial 4 years were evaluated.

RESULTS

Eighty-seven participants were included for analysis (median age: 27 years, range: 3-71 years). A total of 96.5% had obesity, and 3.5% had overweight at maximal weight. Seventy-five had brain tumors (86%)-the majority were craniopharyngiomas (72% of those with tumors). Nontumor etiologies included congenital brain malformation (4.6%), traumatic brain injury (3.4%), and genetic anomaly (2.3%). Ninety percent received obesity treatments including nutritional counseling (82%), pharmacotherapy (59%), bariatric surgery (8%), and vagal nerve stimulation (1%). Forty-six percent reported follow-up BMI results after obesity treatment. Surgery was most effective (median BMI decrease: -8.2 kg/m2 , median interval: 2.6 years), with lifestyle intervention (BMI: -3.4 kg/m2 , interval: 1.2 years) and pharmacological therapy (BMI: -2.3 kg/m2 , interval: 0.8 years) being less effective. Eighty percent of participants reporting follow-up weight remained in the obesity range.

CONCLUSIONS

IRHOD identified a large cohort with self-reported HyOb. Surgical therapy was most effective at weight reduction. Nutritional counseling and pharmacotherapy modestly improved BMI. Stepwise treatment strategy for HyOb (including nutritional, pharmacological, and surgical therapies in an experienced center) may be most valuable.

Therapeutic outcomes of transsphenoidal surgery in pediatric patients with craniopharyngiomas: a single-center study

OBJECTIVE The aim of this study was to analyze the outcomes of transsphenoidal surgery (TSS) in a single-center clinical series of pediatric craniopharyngioma patients treated with gross-total resection (GTR). METHODS The authors retrospectively reviewed the surgical outcomes for 65 consecutive patients with childhood craniopharyngiomas (28 girls and 37 boys, mean age 9.6 years) treated with TSS (45 primary and 20 repeat surgeries) between 1990 and 2015. Tumors were classified as subdiaphragmatic or supradiaphragmatic. Demographic and clinical characteristics, including extent of resection, complications, incidence of recurrence, pre- and postoperative visual disturbance, pituitary function, and incidence of diabetes insipidus (DI), as well as new-onset obesity, were analyzed and compared between the primary surgery and repeat surgery groups. RESULTS Of the 45 patients in the primary surgery group, 26 (58%) had subdiaphragmatic tumors and 19 had supradiaphragmatic tumors. Of the 20 patients in the repeat surgery group, 9 (45%) had subdiaphragmatic tumors and 11 had supradiaphragmatic tumors. The only statistically significant difference between the 2 surgical groups was in tumor size; tumors were larger (mean maximum diameter 30 mm) in the primary surgery group than in the repeat surgery group (25 mm) (p = 0.008). GTR was accomplished in 59 (91%) of the 65 cases; the GTR rate was higher in the primary surgery group than in the repeat surgery group (98% vs 75%, p = 0.009). Among the patients who underwent GTR, 12% experienced tumor recurrence, with a median follow-up of 7.8 years, and recurrence tended to occur less frequently in primary than in repeat surgery patients (7% vs 27%, p = 0.06). Of the 45 primary surgery patients, 80% had deteriorated pituitary function and 83% developed DI, whereas 100% of the repeat surgery patients developed these conditions. Among patients with preoperative visual disturbance, vision improved in 62% but worsened in 11%. Visual improvement was more frequent in primary than in repeat surgery patients (71% vs 47%, p < 0.001), whereas visual deterioration was less frequent following primary surgery than repeat surgery (4% vs 24%, p = 0.04). Among the 57 patients without preoperative obesity, new-onset postoperative obesity was found in 9% of primary surgery patients and 21% of repeat surgery patients (p = 0.34) despite aggressive resection, suggesting that hypothalamic dysfunction was rarely associated with GTR by TSS in this series. However, obesity was found in 25% of the repeat surgery patients preoperatively due to prior transcranial surgery. Although there were no perioperative deaths, there were complications in 12 cases (18%) (6 cases of CSF leaks, 3 cases of meningitis, 2 cases of transient memory disturbance, and 1 case of hydrocephalus). Postoperative CSF leakage appeared to be more common in repeat than in primary surgery patients (20% vs 4.4%, p = 0.2). CONCLUSIONS The results of TSS for pediatric craniopharyngioma in this case series suggest that GTR should be the goal for the first surgical attempt. GTR should be achievable without serious complications, although most patients require postoperative hormonal replacement. When GTR is not possible or tumor recurrence occurs after GTR, radiosurgery is recommended to prevent tumor regrowth or progression.

A 52-week pilot study of the effects of exenatide on body weight in patients with hypothalamic obesity

OBJECTIVE

Hypothalamic obesity (HO) is a common complication of hypothalamic tumors, and effective therapies are lacking. The objective of this pilot study was to investigate changes in body weight before and during treatment with exenatide.

METHODS

This was a prospective, open-label, 52-week pilot study of exenatide (10 mcg b.i.d.) in adults with HO. Ten patients enrolled, and eight completed the study. Study measures included indirect calorimetry, body composition, buffet meals, diet recall, actigraphy, and hormone assays.

RESULTS

Participants had obesity with a baseline weight of 137.2 ± 37.6 kg. Exenatide therapy was well tolerated. Change in weight with exenatide therapy was not significant (-1.4 ± 4.3 kg [95% CI -4.9 to 2.2], P = 0.40), but six out of eight completers lost weight (-6.2 to -0.2 kg). Participants reported significantly lower intake on food recall during treatment compared with baseline (7837.8 ± 2796.6 vs. 6258.4 ± 1970.7 kJ [95% CI -2915.8 to -242.6], P = 0.027), but there was no change in intake during buffet meals.

CONCLUSIONS

Significant weight loss was not observed in patients with HO treated with exenatide, but 75% of completers had stable or decreasing weight. Further studies are needed to evaluate weight loss efficacy in patients with HO.

Reproductive alterations in hyperinsulinemic but normoandrogenic MSG obese female rats

Obesity and metabolic syndrome are the common causes of reproductive and fertility disorders in women. In particular, polycystic ovary syndrome, which is clinically characterized by hyperandrogenism, oligo/anovulation, and polycystic ovarian morphology, has been increasingly associated with metabolic disorders. However, given the broad interplay between metabolic and reproductive functions, this remains a field of intense research. In this study, we investigated the effect of monosodium l-glutamate (MSG)-induced obesity on reproductive biology of female rats. Newborn female rats were subcutaneously injected with MSG (4g/kg/day) or equiosmolar saline (CTR) each 2 days up to postnatal day (pnd) 10. On pnd 60, estrous cycle was evaluated using vaginal smears twice a day for 15 days, which showed MSG rats to be oligocyclic. Thereafter, animals were killed on estrous phase for blood and tissue collection. MSG rats had increased body mass, accumulation of retroperitoneal and visceral fat pads, and visceral adipocyte hypertrophy compared with CTR rats. MSG rats were also dyslipidemic and hyperinsulinemic but were normoglycemic and normoandrogenic. Ovarian morphology analysis showed that MSG rats had a two-fold decrease in oocyte count but a six-fold increase on ovarian follicular cysts, along with a higher number of total primordial and atretic follicles. Moreover, MSG rats had a four-fold increase in anti-Müllerian hormone immunohistochemical staining on antral follicles. Taken together, data presented here characterize MSG obesity as a unique model to study the metabolic pathways underlying reproductive disorders in the absence of overactivated hypothalamic-pituitary-gonadal axis.

Hypothalamic Obesity in Craniopharyngioma Patients: Disturbed Energy Homeostasis Related to Extent of Hypothalamic Damage and Its Implication for Obesity Intervention

Hypothalamic obesity (HO) occurs in patients with tumors and lesions in the medial hypothalamic region. Hypothalamic dysfunction can lead to hyperinsulinemia and leptin resistance. This review is focused on HO caused by craniopharyngiomas (CP), which are the most common childhood brain tumors of nonglial origin. Despite excellent overall survival rates, CP patients have substantially reduced quality of life because of significant long-term sequelae, notably severe obesity in about 50% of patients, leading to a high rate of cardiovascular mortality. Recent studies reported that both hyperphagia and decreased energy expenditure can contribute to severe obesity in HO patients. Recognized risk factors for severe obesity include large hypothalamic tumors or lesions affecting several medial and posterior hypothalamic nuclei that impact satiety signaling pathways. Structural damage in these nuclei often lead to hyperphagia, rapid weight gain, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue. To date, most efforts to treat HO have shown disappointing long-term success rates. However, treatments based on the distinct pathophysiology of disturbed energy homeostasis related to CP may offer options for successful interventions in the future.

Neuroendocrine Disorders in Pediatric Craniopharyngioma Patients

Childhood-onset craniopharyngiomas are partly cystic embryonic malformations of the sellar/parasellar region. The therapy of choice in patients with favorable tumor localization is complete resection with a specific focus on maintaining optical and hypothalamic neuroendocrine functions. In patients with unfavorable tumor localization (i.e., hypothalamic involvement), a limited hypothalamus-sparing surgical strategy followed by local irradiation is recommended. Involvement and/or surgical lesions of posterior hypothalamic areas cause major neuroendocrine sequelae. The overall survival rates are high (92%) but neuroendocrine disorders such as obesity and metabolic syndrome due to involvement and/or treatment-related hypothalamic lesions have major negative impact on survival and quality of life. Recurrences and progressions are frequent post-surgical events. Because irradiation is efficient in preventing tumor progression, appropriate timing of post-surgical irradiation is currently under investigation in a randomized multinational trial (KRANIOPHARYNGEOM 2007). Childhood-onset craniopharyngioma should be recognized as a chronic disease requiring treatment and constant monitoring of the clinical and quality of life consequences, frequently impaired due to neuroendocrine disorders, by experienced multidisciplinary teams in order to provide optimal care of surviving patients.

Craniopharyngioma

Craniopharyngiomas are partly cystic embryogenic malformations of the sellar and parasellar region. With an overall incidence of 0.5-2.0 new cases per million population per year, approximately 30-50% of all cases represent childhood craniopharyngioma. Typical manifestations at diagnosis are some combination of headache, visual impairment, polyuria/polydypsia, growth retardation, and significant weight gain. Therapy of choice in patients with favorable tumor localization is complete resection with specific focus on maintaining functions of the optic nerve and hypothalamic-pituitary axes. In patients whose unfavorable tumor localization makes maintaining hypothalamic functionality surgically challenging, a limited resection followed by local irradiation is recommended. The overall survival rates are high (92%) but occurrences of reduced quality of life are also high. Recurrences after complete resection and progressions of residual tumor after incomplete resection are frequent postsurgical events. Because irradiation is efficient in preventing tumor progression, appropriate timing of postsurgical irradiation is currently under investigation in the randomized multinational trial KRANIOPHARYNGEOM 2007 that analyzes quality of life as primary endpoint. Childhood craniopharyngioma should be recognized as a chronic disease requiring constant monitoring of the clinical and quality of life consequences in order to provide optimal care of surviving patients.

Trends in treatment and outcomes of pediatric craniopharyngioma, 1975-2011

BACKGROUND

Craniopharyngioma tumors and their treatment can lead to significant long-term morbidity due to their proximity to vital structures. The optimal treatment has been debated for many years. We aimed to review the long-term outcomes of children treated for craniopharyngioma in our institution over the past decade and describe trends in treatment and outcomes over the past 3 decades.

METHODS

Charts of children with craniopharyngioma treated and followed at The Hospital for Sick Children between 2001 and 2011 were reviewed. Data regarding findings at diagnosis, treatment, and long-term outcomes were analyzed. Comparison was made with previously published data from our institution.

RESULTS

Data from 33 patients are included; mean age at treatment, 10.7 ± 4.8 years. In 18 children (55%), the initial surgical approach was tumor cyst decompression with or without adjuvant therapy, compared with only 0-2% in the preceding decades (P < .01). Diabetes insipidus occurred in 55% of children and panhypopituitarism in 58% compared with 88% (P < .01) and 86% (P < .01), respectively, in the previous 10 years. Overall, there was a 36% reduction in the number of children who developed severe obesity compared with the preceding decade. Body mass index at follow-up was associated with body mass index at diagnosis (P = .004) and tumor resection as an initial treatment approach (P = .028).

CONCLUSIONS

A shift in surgical treatment approach away from gross total resection has led to improved endocrine outcomes. This may have beneficial implications for quality of life in survivors.

Hypothalamic obesity in patients with craniopharyngioma: treatment approaches and the emerging role of gastric bypass surgery

Hypothalamic obesity is a potential sequela of craniopharyngioma, arising from hypothalamic damage inflicted by either the tumor and/or its treatment. The marked weight gain that characterizes this disorder appears to result from impaired sympathoadrenal activation, parasympathetic dysregulation, and other hormonal and hypothalamic disturbances that upset the balance between energy intake and expenditure. Given hypopituitarism is commonly present, careful management of hormonal deficits is important for weight control in these patients. In addition, diet, exercise, and pharmacotherapy aimed at augmenting sympathetic output, controlling hyperinsulinism, and promoting weight loss have been used to treat this disease, but these measures rarely lead to sustained weight loss. While surgical interventions have not routinely been pursued, emerging data suggests that surgical weight loss interventions including Roux-en-Y gastric bypass can be safely and effectively used for the management of hypothalamic obesity in patients with craniopharyngioma.

Functional neuroimaging in craniopharyngioma: a useful tool to better understand hypothalamic obesity?

OBJECTIVE

To use functional magnetic resonance imaging (fMRI) in craniopharyngioma (CP) patients to examine the hypothesis that hypothalamic damage due to CP and its treatment results in enhanced perception of food reward and/or impaired central satiety processing.

METHODS

Pre- and post-meal responses to visual food cues in brain regions of interest (ROI; bilateral nucleus accumbens, bilateral insula, and medial orbitofrontal cortex) were assessed in 4 CP patients versus 4 age- and weight-matched controls. Stimuli consisted of images of high- ('fattening') and low-calorie ('non-fattening') foods in blocks, alternating with non-food object blocks. After the first fMRI scan, subjects drank a high-calorie test meal to suppress appetite, then completed a second fMRI scan. Within each ROI, we calculated mean z-scores for activation by fattening as compared to non-fattening food images.

RESULTS

Following the test meal, controls showed suppression of activation by food cues while CP patients showed trends towards higher activation.

CONCLUSION

These data, albeit in a small group of patients, support our hypothesis that perception of food cues may be altered in hypothalamic obesity (HO), especially after eating, i.e. in the satiated state. The fMRI approach is encouraging for performing future mechanistic studies of the brain response to food cues and satiety in patients with hypothalamic or other forms of childhood obesity.

Bariatric surgery in hypothalamic obesity

Craniopharyngiomas (CP) are epithelial neoplasms generally found in the area of the pituitary and hypothalamus. Despite benign histology, these tumors and/or their treatment often result in significant, debilitating disorders of endocrine, neurological, behavioral, and metabolic systems. Severe obesity is observed in a high percentage of patients with CP resulting in significant comorbidities and negatively impacting quality of life. Obesity occurs as a result of hypothalamic damage and disruption of normal homeostatic mechanisms regulating energy balance. Such pathological weight gain, termed hypothalamic obesity (HyOb), is often severe and refractory to therapy. Unfortunately, neither lifestyle intervention nor pharmacotherapy has proven effective in the treatment of HyOb. Given the limited choices and poor results of these treatments, several groups have examined bariatric surgery as a treatment alternative for patients with CP-HyOb. While a large body of evidence exists supporting the use of bariatric surgery in the treatment of exogenous obesity and its comorbidities, its role in the treatment of HyOb has yet to be defined. To date, the existing literature on bariatric surgery in CP-HyOb is largely limited to case reports and series with short term follow-up. Here we review the current reports on the use of bariatric surgery in the treatment of CP-HyOb. We also compare these results to those reported for other populations of HyOb, including Prader-Willi Syndrome, Bardet-Biedl syndrome, and hypothalamic melanocortin signaling defects. While initial reports of bariatric surgery in CP-HyOb are promising, their limited scope makes it difficult to draw any substantial conclusions as to the long term safety and efficacy of bariatric surgery in CP-HyOb. There continues to be a need for more robust, controlled, prospective studies with long term follow-up in order to better define the role of bariatric surgery in the treatment of HyOb.

Long term sequelae of pediatric craniopharyngioma - literature review and 20 years of experience

Craniopharyngioma are rare histologically benign brain tumors that develop in the pituitary-hypothalamic area. They may invade nearby anatomical structures causing significant rates of neurological, neurocognitive, and endocrinological complications including remarkable hypothalamic damage. Information regarding long term implications of the tumors and treatment in the pediatric population is accumulating, and treatment goals appear to be changing accordingly. In this review we aim to present data regarding long term complications of craniopharyngioma in children and adolescents and our experience from a large tertiary center. Hypothalamic dysfunction was noted to be the most significant complication, adversely affecting quality of life in survivors. Obesity, fatigue, and sleep disorders are the most notable manifestations of this dysfunction, and treatment is extremely difficult. Changes in management in recent years show a potential for improved long term outcomes; we found a trend toward less aggressive surgical management and increasing use of adjuvant treatment, accompanied by a decrease in complication rates.

Surgical strategies in childhood craniopharyngioma

Craniopharyngiomas are biologically benign lesions (WHO Grade 1) of the sellar and suprasellar region, associated with a serious morbidity. About 50% of these tumors become clinically apparent during childhood. Clinical symptoms include headaches, chiasm syndrome, hydrocephalus, pituitary insufficiencies, and obesity. Growth arrest is a typical symptom in children. The treatment of craniopharyngiomas includes surgery as well as radiotherapy. The goal of surgery varies according to the tumor location and extension and may range from complete resection to biopsy. Surgical complications are well known and cause constant evaluation of surgical strategies. Diencephalic obesity is related to surgical manipulation of hypothalamic tissue. Therefore, a classification system for craniopharyngiomas based on preoperative MRI is suggested by the authors. Recurrences are frequent in craniopharyngiomas, even after complete or gross-total resection. Radiotherapy is therefore recommended to patients with incomplete resections. However, the ideal time for radiotherapy after surgery is under discussion. The treatment of craniopharyngiomas requires an interdisciplinary and multimodal approach. Each patient should receive an individually tailored treatment. Surgically, different approaches as well as different degrees of resection can be considered, depending on tumor location and tumor extension.

Hypothalamic obesity after craniopharyngioma: mechanisms, diagnosis, and treatment

Obesity is a common complication after craniopharyngioma therapy, occurring in up to 75% of survivors. Its weight gain is unlike that of normal obesity, in that it occurs even with caloric restriction, and attempts at lifestyle modification are useless to prevent or treat the obesity. The pathogenesis of this condition involves the inability to transduce afferent hormonal signals of adiposity, in effect mimicking a state of CNS starvation. Efferent sympathetic activity drops, resulting in malaise and reduced energy expenditure, and vagal activity increases, resulting in increased insulin secretion and adipogenesis. Lifestyle intervention is essentially useless in this syndrome, termed "hypothalamic obesity." Pharmacologic treatment is also difficult, consisting of adrenergics to mimic sympathetic activity, or suppression of insulin secretion with octreotide, or both. Recently, bariatric surgery (Roux-en-Y gastric bypass, laparoscopic gastric banding, truncal vagotomy) have also been attempted with variable results. Early and intensive management is required to mitigate the obesity and its negative consequences.

Carcinoembryonic antigen-related cell adhesion molecule 2 controls energy balance and peripheral insulin action in mice

BACKGROUND & AIMS

The carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is a transmembrane glycoprotein with pleotropic functions, including clearance of hepatic insulin. We investigated the functions of the related protein CEACAM2, which has tissue-specific distribution (kidney, uterus, and crypt epithelia of intestinal tissues), in genetically modified mice.

METHODS

Ceacam2-null mice (Cc2-/-) were generated from a 129/SvxC57BL/6J background. Female mice were assessed by hyperinsulinemic-euglycemic clamp analysis and indirect calorimetry and body fat composition was measured. Cc2-/- mice and controls were fed as pairs, given insulin tolerance tests, and phenotypically characterized.

RESULTS

Female, but not male Cc2-/- mice exhibited obesity that resulted from hyperphagia and reduced energy expenditure. Pair feeding experiments showed that hyperphagia led to peripheral insulin resistance. Insulin action was normal in liver but compromised in skeletal muscle of female Cc2-/- mice; the mice had incomplete fatty acid oxidation and impaired glucose uptake and disposal. The mechanism of hyperphagia in Cc2-/- mice is not clear, but appears to result partly from increased hyperinsulinemia-induced hypothalamic fatty acid synthase levels and activity. Hyperinsulinemia was caused by increased insulin secretion.

CONCLUSIONS

In mice, CEACAM2 is expressed by the hypothalamus. Cc2-/- mice develop obesity from hyperphagia and reduced energy expenditure, indicating its role in regulating energy balance and insulin sensitivity.

Energy expenditure in obesity associated with craniopharyngioma

BACKGROUND AND PURPOSE

Obesity is a common yet incompletely understood complication of childhood craniopharyngioma. We hypothesized that craniopharyngioma is associated with specific defects in energy balance compared to obese control children.

METHODS

Eleven craniopharyngioma patients were recruited for a study on body composition and energy balance. Eight subjects were obese. The obese craniopharyngioma patients had a mean age (+/-SD) of 11.2 +/- 1.7 years. The average body mass index z score was 2.33 (+/-0.32). A previously studied group of obese children (BMI z score 2.46 +/- 0.46) served as controls. Resting energy expenditure (REE) was determined by indirect calorimetry and body composition by dual energy X-ray absorptiometry in all children.

RESULTS

Obese craniopharyngioma patient subjects had increased mean (+/-standard error) fat-free mass compared to obese controls (57% +/- 0.88 % vs 50.0% +/- 0.87%, p = 0.02). The obese craniopharyngioma patients had a 17% lower REE compared to values expected from the World Health Organization equation (1,541 +/- 112.6 vs 1,809 +/- 151.8 kcal; p = 0.01). In contrast, the obese control children had measured REE within 1% of predicted (1,647 +/- 33.2 vs. 1,652 +/- 40.2; p = 0.8). In a linear regression model, REE remained significantly lower than predicted after controlling for FFM.

CONCLUSIONS

Lower REE may be a factor contributing to obesity in children with craniopharyngioma. Further study is needed into the mechanisms for reduced energy expenditure in patients with craniopharyngioma.

Association of monosodium glutamate intake with overweight in Chinese adults: the INTERMAP Study

Animal studies indicate that monosodium glutamate (MSG) can induce hypothalamic lesions and leptin resistance, possibly influencing energy balance, leading to overweight. This study examines the association between MSG intake and overweight in humans. We conducted a cross-sectional study involving 752 healthy Chinese (48.7% women), aged 40-59 years, randomly sampled from three rural villages in north and south China. The great majority of participants prepared their foods at home, without use of commercially processed foods. Diet was assessed with four in-depth multipass 24-h recalls. Participants were asked to demonstrate MSG amounts added in food preparation. Amounts shaken out were weighed by trained interviewers. Overweight was defined as BMI > or =25.0 or > or =23.0 kg/m(2)(based on World Health Organization recommendations for Asian populations). Eighty-two percent of participants were MSG users. Average intake was 0.33 g/day (s.d. = 0.40). With adjustment for potential confounders including physical activity and total energy intake, MSG intake was positively related to BMI. Prevalence of overweight was significantly higher in MSG users than nonusers. For users in the highest tertile of MSG intake compared to nonusers, the multivariable-adjusted odds ratios of overweight (BMI > or =23.0 and > or =25.0) were 2.10 (95% confidence interval, 1.13-3.90, P for trend across four MSG categories = 0.03) and 2.75 (95% confidence interval, 1.28-5.95, P = 0.04). This research provides data that MSG intake may be associated with increased risk of overweight independent of physical activity and total energy intake in humans.

Prevalence of obesity, hyperlipemia and insulin resistance in children with suprasellar brain tumors

Weight gain is a common sequela of suprasellar tumors, referred to as hypothalamic obesity. We undertook an evaluation of obesity and metabolic aberrations among patients treated at our institute. During the 12 mo from Apr. 2005, 23 patients (10 males and 13 females) with remitted suprasellar tumors attended our clinic: 10 patients with craniopharyngioma, 7 with germinoma, 4 with optic nerve glioma and others. Of these, 12 patients (52%) were found to have obesity on the basis of percent overweight and/or percent body fat. Elevated cholesterol and/or triglyceride (TG) was found in 9 patients (39%), and insulin resistance was suspected in 7 patients (30%). Three patients exhibited strikingly elevated postprandial TG levels. All 6 patients with the growth without GH phenomenon had at least one metabolic aberration. In conclusion, the prevalence of hypothalamic obesity was nearly half in our series, and hyperlipemia and insulin resistance were also frequently found. The increased risk for metabolic aberration in growth without GH patients was suggested.

Central nervous system regulation of liver and adipose tissue metabolism

Hypothalamic and autonomic nervous regulation of carbohydrate and amino acid metabolism in the liver and of lipid metabolism in adipose tissues is described. The direct neural mechanism underlying this regulation has been evaluated. Electrical stimulation of the ventromedial hypothalamic nucleus (VMH)-splanchnic nerve system causes glycogenolysis in the liver by rapid activation of glycogen phosphorylase, whereas electrical stimulation of the lateral hypothalamic nucleus (LH)-vagus nerve system promotes glycogenesis in the liver by activation of glycogen synthetase, through direct neural and neural-hormonal mechanisms. Studies on chemical coding of the hypothalamic neurones have revealed that norepinephrine-sensitive neurones in the VMH and acetylcholine-sensitive neurones in the LH are specifically involved in the regulation of liver phosphorylase and glycogen synthetase, respectively. Acetylcholine-sensitive neurones of the LH were also found to be concerned in regulation of hepatic tyrosine aminotransferase activity, through intermediation of the cholinergic system in the LH-vagal pathway. Finally, it has been shown that the VMH acts as a regulatory centre for lipolysis in adipose tissues by modulating activation of the sympathetic nervous system. In addition, stimulation of the VMH enhanced lipogenesis in brown adipose tissue preferentially, probably through a mechanism mediated by sympathetic innervation of this tissue. The latter finding suggests that both the breakdown and resynthesis of triglycerides in brown adipose tissue, but not in white adipose tissue, are accelerated by stimulation of the VMH.