Prevalence of endocrine disorders in obese patients: systematic review and meta-analysis

OBJECTIVE

The increasing prevalence of obesity is expected to promote the demand for endocrine testing. To facilitate evidence guided testing, we aimed to assess the prevalence of endocrine disorders in patients with obesity. The review was carried out as part of the Endocrine Work-up for the Obesity Guideline of the European Society of Endocrinology.

DESIGN

Systematic review and meta-analysis of the literature.

METHODS

A search was performed in MEDLINE, EMBASE, Web of Science and COCHRANE Library for original articles assessing the prevalence of hypothyroidism, hypercortisolism, hypogonadism (males) or hyperandrogenism (females) in patients with obesity. Data were pooled in a random-effects logistic regression model and reported with 95% confidence intervals (95% CI).

RESULTS

Sixty-eight studies were included, concerning a total of 19.996 patients with obesity. The pooled prevalence of overt (newly diagnosed or already treated) and subclinical hypothyroidism was 14.0% (95% CI: 9.7-18.9) and 14.6% (95% CI: 9.2-20.9), respectively. Pooled prevalence of hypercortisolism was 0.9% (95% CI: 0.3-1.6). Pooled prevalence of hypogonadism when measuring total testosterone or free testosterone was 42.8% (95% CI: 37.6-48.0) and 32.7% (95% CI: 23.1-43.0), respectively. Heterogeneity was high for all analyses.

CONCLUSIONS

The prevalence of endocrine disorders in patients with obesity is considerable, although the underlying mechanisms are complex. Given the cross-sectional design of the studies included, no formal distinction between endocrine causes and consequences of obesity could be made.

Chemotherapy with cyclophosphamide, vincristine and dacarbazine for malignant paraganglioma and pheochromocytoma: systematic review and meta-analysis

BACKGROUND

Chemotherapy with cyclophosphamide, vincristine and dacarbazine (CVD) can be used for palliative treatment of malignant pheochromocytoma and paraganglioma. However, the precise effect of this chemotherapeutic regimen on tumour volume is unclear. The main objective of this study was to perform a systematic review and meta-analysis assessing the effect of chemotherapy with CVD on tumour volume in patients with malignant paraganglioma/pheochromocytoma.

METHODS

A literature search was performed in October 2013 to identify potentially relevant studies. Main outcomes were the pooled percentages of complete response, partial response and stable disease after chemotherapy with CVD. A meta-analysis was performed with an exact likelihood approach using a logistic regression. Pooled percentages with 95% confidence intervals (CI) were reported.

RESULTS

Four studies concerning a total of 50 patients with malignant paraganglioma/pheochromocytoma reported on treatment with a combination of CVD chemotherapy. A meta-analysis of the effect of chemotherapy on tumour volume showed pooled percentages of complete response, partial response and stable disease of, respectively, 4% (95% CI: 1%-15%), 37%(95% CI: 25%-51%) and 14% (95% CI: 7%-27%). Only two studies concerning a total of 35 patients assessed the response on catecholamine excess; pooled percentages for complete, partial and stable hormonal response were 14% (95% CI: 6%-30%), 40% (95% CI: 25%-57%) and 20% (95% CI: 10%-36%), respectively. Duration of response was also reported in only two studies with a median duration of response of 20 months and 40 months.

CONCLUSIONS

Data on the effects of a combination of CVD chemotherapy on malignant paraganglioma/pheochromocytoma suggest that a partial response concerning tumour volume can be achieved in about 37% of patients and a partial response on catecholamine excess in about 40% of patients. However, in the included studies, the protocol when to initiate treatment was not well described. Therefore, it cannot be excluded that the reported effect of chemotherapy on tumour volume reflects the natural course of the disease, at least partially.

(131)I-MIBG therapy for malignant paraganglioma and phaeochromocytoma: systematic review and meta-analysis

BACKGROUND

(131)I-MIBG therapy can be used for palliative treatment of malignant paraganglioma and phaeochromocytoma. The main objective of this study was to perform a systematic review and meta-analysis assessing the effect of (131)I-MIBG therapy on tumour volume in patients with malignant paraganglioma/phaeochromocytoma.

METHODS

A literature search was performed in December 2012 to identify potentially relevant studies. Main outcomes were the pooled proportions of complete response, partial response and stable disease after radionuclide therapy. A meta-analysis was performed with an exact likelihood approach using a logistic regression with a random effect at the study level. Pooled proportions with 95% confidence intervals (CI) were reported.

RESULTS

Seventeen studies concerning a total of 243 patients with malignant paraganglioma/phaeochromocytoma were treated with (131)I-MIBG therapy. The mean follow-up ranged from 24 to 62 months. A meta-analysis of the effect of (131)I-MIBG therapy on tumour volume showed pooled proportions of complete response, partial response and stable disease of, respectively, 0·03 (95% CI: 0·06-0·15), 0·27 (95% CI: 0·19-0·37) and 0·52 (95% CI: 0·41-0·62) and for hormonal response 0·11 (95% CI: 0·05-0·22), 0·40 (95% CI: 0·28-0·53) and 0·21 (95% CI: 0·10-0·40), respectively. Separate analyses resulted in better results in hormonal response for patients with paraganglioma than for patients with phaeochromocytoma.

CONCLUSIONS

Data on the effects of (131)I-MIBG therapy on malignant paraganglioma/phaeochromocytoma suggest that stable disease concerning tumour volume and a partial hormonal response can be achieved in over 50% and 40% of patients, respectively, treated with (131)I-MIBG therapy. It cannot be ruled out that stable disease reflects not only the effect of MIBG therapy, but also (partly) the natural course of the disease.

No difference in phenotype of the main Dutch SDHD founder mutations

OBJECTIVE

SDHD mutations predispose carriers to hereditary paraganglioma syndrome. The objective of this study was to assess the genotype-phenotype correlation of a large Dutch cohort of SDHD mutation carriers and evaluate potential differences in clinical phenotypes due to specific SDHD gene mutations.

DESIGN

Retrospective, descriptive single-centre study.

PATIENTS

All consecutive SDHD mutation carriers followed at the Department of Endocrinology of the Leiden University Medical Center were included.

MEASUREMENTS

Subjects were investigated according to structured protocols used for standard care, including repetitive biochemical and radiological screening for paragangliomas.

RESULTS

Two hundred and one SDHD mutation carriers with a mean age at presentation of 42·6 ± 14·4 years and a mean follow-up of 5·8 ± 5·4 years were evaluated. Eighty-one percent carried the SDHD c.274G>T (p.Asp92Tyr) mutation and 13% the SDHD c.416T>C (p.Leu139Pro) mutation. No differences in clinical phenotype between these two specific SDHD mutations were found. Ninety-one percent developed one or multiple paragangliomas in the head and neck region (HNPGLs), of which the carotid body tumour was the most prevalent (85%). Eighteen carriers developed pheochromocytomas, fifteen sympathetic paragangliomas and nine carriers (4%) suffered from malignant paraganglioma. By end of follow-up, sixteen SDHD mutation carriers (8%) displayed no biochemical or radiological evidence of manifest disease.

CONCLUSIONS

The two main Dutch SDHD founder mutations do not differ in clinical expression. SDHD mutations are associated with the development of multiple HNPGLs and predominantly benign disease.

Avoiding and nonexpressing: coping styles of patients with paragangliomas

CONTEXT

Paraganglioma (PGL) patients and succinate dehydrogenase (SDH) gene mutation carriers at risk for PGLs have a decreased quality of life (QoL). QoL may be affected by the strategy an individual uses when dealing with a stressful situation, ie, specific coping styles. Understanding the various approaches to coping may allow the development of targeted interventions to improve patient QoL.

OBJECTIVE

The objective of the study was to assess coping styles in PGL patients and SDH mutation carriers.

DESIGN

This was a cross-sectional study.

SETTING

The study was conducted at a tertiary referral center.

PATIENTS AND METHODS

Coping styles were assessed using the Utrecht Coping List. The results from the study cohort were compared with a control group and data derived from the literature. Potential differences in coping styles between the various SDH mutation carriers and PGL patients without an SDH mutation were explored.

RESULTS

Of the 174 patients who responded, 122 were SDHD, 25 SDHB, and 2 SDHC mutation carriers. An additional 25 patients lacked an SDH mutation. They recruited 100 peers as controls. Compared with the general population, the study cohort was more avoidant of problems (P < .001) and reported less expression of emotion (P < .01). Compared with patients with other conditions, they sought more social support (P < .001). There were no significant differences in coping styles between the various categories of mutation carriers or PGL patients lacking a mutation.

CONCLUSIONS

Coping styles of PGL patients and SDH mutation carriers differ from those of control and reference groups and include an avoidant coping style and a lack of emotional expression.

Carotid body tumors are not associated with an increased risk for sleep-disordered breathing

PURPOSE

Tumors in the carotid bodies may interfere with their function as peripheral chemoreceptors. An altered control of ventilation may predispose to sleep-disordered breathing. This study aimed to assess whether patients with unilateral or bilateral carotid body tumors (uCBT or bCBT, respectively) or bilateral CBT resection (bCBR) display sleep-disordered breathing and to evaluate the global contribution of the peripheral chemoreceptor to the hypercapnic ventilatory response.

METHODS

Eight uCBT, eight bCBT, and nine bCBR patients and matched controls underwent polysomnography. The peripheral chemoreflex drive was assessed using euoxic and hyperoxic CO2 rebreathing tests. Daytime sleepiness and fatigue were assessed with the Epworth Sleepiness Scale and the Multidimensional Fatigue Index.

RESULTS

All patient groups reported significant fatigue-related complaints, but no differences in excessive daytime sleepiness (EDS) were found. The apnea/hypopnea index (AHI) did not differ significantly between patient groups and controls. Only in bCBT patients, a trend towards a higher AHI was observed, but this did not reach significance (p=0.06). No differences in the peripheral chemoreflex drive were found between patients and controls.

CONCLUSIONS

Patients with (resection of) CBTs have more complaints of fatigue but are not at risk for EDS. The presence or resection of CBTs is neither associated with an altered peripheral chemoreflex drive nor with sleep-disordered breathing.

Quality of life is decreased in patients with paragangliomas

CONTEXT

Germline mutations in succinate dehydrogenase (SDH) genes predispose carriers for developing paragangliomas, and studies on their quality of life (QoL) are scarce.

OBJECTIVES

The objectives of this study were to assess QoL in patients with paragangliomas (PGL), to evaluate long-term QoL, and to explore potential differences in QoL between SDH mutation carriers and paraganglioma patients without an SDH mutation.

DESIGN

Cross-sectional, case-control study.

SETTING

Tertiary referral center.

SUBJECTS

ONE HUNDRED AND SEVENTY FOUR PARAGANGLIOMA PATIENTS WERE INCLUDED: 25 SDHB, two SDHC, and 122 SDHD mutation carriers and 25 patients without an SDH mutation. They provided 100 peers as control persons. Furthermore, patients were compared with age-adjusted reference populations.

MAIN OUTCOME MEASURES

QOL WAS ASSESSED USING THREE VALIDATED HEALTH-RELATED QOL QUESTIONNAIRES: the Hospital Anxiety and Depression Scale, the Multidimensional Fatigue Index 20, and the Short Form 36.

RESULTS

Patients reported a significantly impaired QoL compared with their own controls, mainly on fatigue and physical condition subscales. Compared with age-adjusted literature values, patients had significantly impaired scores on physical, psychological, and social subscales. A decreased QoL was mainly related to paraganglioma-associated complaints. There was no difference in QoL between the various SDH mutation carriers or paraganglioma patients without an SDH mutation. QoL in asymptomatic mutation carriers, i.e. without manifest disease, did not differ from QoL of the general population. Long-term results in 41 patients showed no alteration in QoL besides a reduced level of activity.

CONCLUSION

QoL is decreased in paraganglioma patients but stable when measured over time.