Testosterone Replacement Therapy Added to Intensive Lifestyle Intervention in Older Men With Obesity and Hypogonadism

BACKGROUND

Obesity and hypogonadism additively contribute to frailty in older men; however, appropriate treatment remains controversial.

OBJECTIVE

Determine whether testosterone replacement augments the effect of lifestyle therapy on physical function in older men with obesity and hypogonadism.

DESIGN

Randomized, double-blind, placebo-controlled trial.

SETTING

VA Medical Center.

PARTICIPANTS

83 older (age ≥65 years) men with obesity (body mass index ≥30 kg/m2) and persistently low am testosterone (<10.4 nmol/L) associated with frailty.

INTERVENTIONS

Participants were randomized to lifestyle therapy (weight management and exercise training) plus either testosterone (LT+Test) or placebo (LT+Pbo) for 6 months.

OUTCOME MEASURES

Primary outcome was change in Physical Performance Test (PPT) score. Secondary outcomes included other frailty measures, body composition, hip bone mineral density (BMD), physical functions, hematocrit, prostate specific antigen (PSA), and sex hormones.

RESULTS

PPT score increased similarly in LT+Test and LT+Pbo group (17% vs. 16%; P = 0.58). VO2peak increased more in LT+Test than LT+Pbo (23% vs. 16%; P = 0.03). Despite similar -9% weight loss, lean body mass and thigh muscle volume decreased less in LT+Test than LT+Pbo (-2% vs. -3%; P = 0.01 and -2% vs -4%; P = 0.04). Hip BMD was preserved in LT+Test compared with LT+Pbo (0.5% vs -1.1%; P = 0.003). Strength increased similarly in LT+Test and LT+Pbo (23% vs 22%; P = 0.94). Hematocrit but not PSA increased more in LT+Test than LT+Pbo (5% vs 1%; P < 0.001). Testosterone levels increased more in LT+Test than LT+Pbo (167% vs 27%; P < 0.001).

CONCLUSION

In older, obese hypogonadal men, adding testosterone for 6 months to lifestyle therapy does not further improve overall physical function. However, our findings suggest that testosterone may attenuate the weight loss-induced reduction in muscle mass and hip BMD and may further improve aerobic capacity.

Sensitivity and specificity of the macimorelin test for diagnosis of AGHD

OBJECTIVE

The macimorelin test is approved for the diagnosis of adult growth hormone deficiency (AGHD) based on its efficacy vs the insulin tolerance test (ITT). Macimorelin has a significant advantage over ITT in avoiding hypoglycemia. Analyses were conducted to determine whether macimorelin performance is affected by age, BMI, or sex, and evaluate its performance vs ITT over a range of GH cutpoints.

DESIGN

Post hoc analyses of data from a previous randomized phase 3 study included participants aged 18-66 years with BMI <37 kg/m2 and high (Group A), intermediate (Group B), or low (Group C) likelihood for AGHD based on pituitary history, and matched controls (Group D).

METHODS

Probability of AGHD was estimated using unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted logistic models. Area under the curve (AUC) of the estimated receiver operating characteristic (ROC) curve (range, 0-1; 1 = perfect) was compared for adjusted vs unadjusted models. Separate analyses evaluated agreement, sensitivity, and specificity for macimorelin and ITT using cutpoints of 2.8, 4.0, 5.1, and 6.5 ng/mL.

RESULTS

For participants in Group A (n = 41) and Group D (n = 29), unadjusted, age-adjusted, BMI-adjusted, and sex-adjusted models had ROC AUCs (95% CIs) of 0.9924 (0.9807-1), 0.9924 (0.9807-1), 0.9916 (0.9786-1), and 0.9950 (0.9861-1), respectively.

CONCLUSIONS

Macimorelin performance was not meaningfully affected by age, BMI, or sex, indicating robustness for AGHD diagnosis. Of the 4 GH cutpoints evaluated, the cutpoint of 5.1 ng/mL provided maximal specificity (96%) and high sensitivity (92%) and was in good overall agreement with the ITT at the same cutpoint (87%).

Effect of Body Weight and Other Metabolic Factors on Risk of Non-Small Cell Lung Cancer among Veterans with HIV and a History of Smoking

Simple Summary

Among people living with HIV (PWH), there has been an increasing incidence of non-small cell lung cancer (NSCLC) and metabolic abnormalities, such as diabetes and high cholesterol, which affect the risk of NSCLC. In this article, we evaluate which metabolic risk factors increase the risk of NSCLC among PWH who smoke. Through a retrospective study that includes 33,351 veterans, we found that the risk of NSCLC was lower in well-controlled PWH (1.46 vs. 2.06/1000 patient/year [PY]). Metabolic factors associated with higher NSCLC risk included lower body weight at HIV diagnosis and a remote history of involuntary weight loss in PWH regardless of whether they had a well-controlled infection or not. Lower HDL and triglyceride levels increased the risk of NSCLC only in non-well-controlled smokers. Our results suggest these factors may be important to consider in targeting surveillance and for early identification of NSCLC in PWH smokers.

Abstract

Among people living with HIV (PWH), there has been an increasing incidence of non-small cell lung cancer (NSCLC) and metabolic abnormalities, including dyslipidemia, which can modulate NSCLC risk. In this article, we evaluate which metabolic risk factors are associated with incident risk among PWH who smoke. This is done through a retrospective cohort study, using data of HIV+ veterans who smoke from the nationwide Veterans Affairs (VA) healthcare system. Data on diagnostic codes, medication, and laboratory values of 33,351 veterans were obtained using the VA’s Corporate Data Warehouse and Central Cancer Registry. We calculated NSCLC incidence and utilized Cox regression to determine metabolic factors associated with NSCLC risk. HIV+ cohort was 97.4% male; median age = 47 years and 20,050 (60.1%) well-controlled (≥80% follow-up time undetectable viral load). Crude incidence rates were lower in well-controlled PWH (1.46 vs. 2.06/1000 PY). Metabolic factors associated with incident NSCLC risk included lower BMI at HIV diagnosis and cachexia history in both groups, while HDL and triglycerides were significant in non-well-controlled smokers only. Our findings that lower BMI at HIV diagnosis, history of cachexia among individuals with well-controlled HIV, and cachexia presence at diagnosis are associated with increased risk of developing NSCLC in PWH with a history of smoking have important implications.

Identification of hepatic progenitor cells in the canine fetal liver

The liver plays essential roles in human and animal organisms, such as the storage, release, metabolism, and elimination of various endogenous or exogenous substances. Although its vital importance, few treatments are yet available when a hepatic failure occurs, and hence, the use of stem cells has arisen as a possible solution for both human and veterinary medicines. Previous studies have shown the existence of hepatic progenitor cells in human fetuses that were positive for EpCAM and NCAM. There is limited evidence, however, further identification and characterization of these cells in other species. Considering the similarity between dogs and humans regarding physiology, and also the increasing importance of developing new treatments for both veterinary and translational medicine, this study attempted to identify hepatic progenitor cells in canine fetal liver. For that, livers from canine fetuses were collected, cells were isolated by enzymatic digestion and cultured. Cells were characterized regarding morphology and expression of EpCAM, NCAM, Nestin, and Thy-1/CD90 markers. Our results suggest that it is possible to identify hepatic progenitor cells in the canine fetal liver; however, for therapeutic use, further techniques for cellular isolation and culture are necessary to obtain enriched populations of hepatic progenitors from the canine fetal liver.

Ghrelin ameliorates tumor-induced adipose tissue atrophy and inflammation via Ghrelin receptor-dependent and -independent pathways

Adipose tissue (AT) atrophy is a hallmark of cancer cachexia contributing to increased morbidity/mortality. Ghrelin has been proposed as a treatment for cancer cachexia partly by preventing AT atrophy. However, the mechanisms mediating ghrelin's effects are incompletely understood, including the extent to which its only known receptor, GHSR-1a, is required for these effects. This study characterizes the pathways involved in AT atrophy in the Lewis Lung Carcinoma (LLC)-induced cachexia model and those mediating the effects of ghrelin in Ghsr ^+/+ and Ghsr ^-/- mice. We show that LLC causes AT atrophy by inducing anorexia, and increasing lipolysis, AT inflammation, thermogenesis and energy expenditure. These changes were greater in Ghsr ^-/-. Ghrelin administration prevented LLC-induced anorexia only in Ghsr ^+/+, but prevented WAT lipolysis, inflammation and atrophy in both genotypes, although its effects were greater in Ghsr ^+/+. LLC-induced increases in BAT inflammation, WAT and BAT thermogenesis, and energy expenditure were not affected by ghrelin. In conclusion, ghrelin ameliorates WAT inflammation, fat atrophy and anorexia in LLC-induced cachexia. GHSR-1a is required for ghrelin's orexigenic effect but not for its anti-inflammatory or fat-sparing effects.

Evaluation of physical function and its association with body composition, quality of life and biomarkers in cancer cachexia patients

BACKGROUND & AIMS

There are currently no approved treatments for cancer cachexia. One of the main barriers to developing a treatment for this indication is the lack of consensus on clinically important tools for assessing functional impairment in this setting. This issue is of critical importance because functional improvement is likely to be required for approval by regulatory agencies. This cross-sectional study aimed to evaluate various functional performance measures and establish their association with body composition, energy expenditure, biomarkers, and patient-reported quality of life (QOL).

METHODS

Physical function, body composition, energy expenditure, cytokines, testosterone, and patient-reported QOL were compared between men with solid tumors with cachexia (CAC; N = 48), without cachexia (CNC; N = 48), and weight-stable patients without cancer (CON; N = 37). Receiver Operator Characteristic curves and multivariate regression were performed to identify functional impairment cut-points and predictors of physical function, respectively.

RESULTS

Patients with CAC displayed lower total lean and appendicular lean mass, stair climb power (SCP), upper body strength, and bioavailable testosterone, and displayed higher energy expenditure than CNC or CON (p ≤ 0.03); CAC showed lower handgrip, respiratory quotient, and appetite, and higher cytokines and fatigue than CON (p ≤ 0.032). A cut-point of 336 Watts for SCP provided 78% sensitivity and 77% specificity for classification of CAC (p = 0.001); SCP also performed better than other measures tested when compared to CON-derived normatives. Upper body strength exhibited moderate sensitivity and specificity for classification of CAC (p ≤ 0.02). Elevated relative energy expenditure and cytokines negatively predicted, and muscle mass positively predicted, various muscle strength outcomes.

CONCLUSION

Stair climb power and upper body strength may have potential as discriminatory tests for functional impairment in patients with cancer cachexia.

Muscle mass, not radiodensity, predicts physical function in cancer patients with or without cachexia

Background: There is a need to better understand the relationship between functional impairment and muscle mass in cancer cachexia. This study aimed to establish the relationship between computed tomography (CT)-derived muscle cross-sectional area (CSA), radiodensity, and skeletal muscle index (SMI) and dual energy X-ray absorptiometry (DXA) parameters with functional performance in cancer patients.

Materials and Methods: Handgrip strength, stair climb power (SCP), one-repetition maximum (1RM) strength, and body composition (CT and DXA) were compared across cancer patients with cachexia (CAC; N = 28), without cachexia (CNC; N = 28), and non-cancer patients (CON; N = 19). Multivariate regression was performed to find predictors of function.

Results: CAC had lower CT muscle CSA and SMI and lower DXA appendicular lean mass (ALM) than CNC or CON (p ≤ 0.011). Muscle radiodensity was not different across groups despite larger proportion of low CT SMI in CAC, and CAC performed worse in SCP than CON (p = 0.018). In cancer patients, DXA ALM and CT muscle CSA each predicted physical function (p ≤ 0.05); muscle radiodensity did not, and DXA ALM explained more variability in SCP and 1RM than CT muscle CSA.

Conclusions: Stair climb power was reduced in cancer cachexia; muscle radiodensity was not. Muscle mass by CT or DXA, but not radiodensity, predicted functional performance in cancer patients.

Clinical research in older adults with hematologic malignancies: Opportunities for alignment in the Veterans Affairs

Management of hematologic malignancies in older patients is complex and, with recent and anticipated trends in demographics, increasingly common. As a large, nationally integrated medical system the Veterans Affairs has the potential to lead in research to benefit these patients. In this review we describe the evolving treatment paradigms of hematologic malignancies and how they are best fit with older patients through comprehensive evaluation of key vulnerabilities. We also discuss optimization of supportive care and navigation services to target identified risks and challenges aimed at ameliorating the patient's burden of cancer and treatment. Lastly, we discuss opportunities in design of prospective clinical trials to better align with real-world cases, thereby expanding enrollment of and applicability to older patients with hematologic malignancies.

Elimination of Age-Associated Hepatic Steatosis and Correction of Aging Phenotype by Inhibition of cdk4-C/EBPα-p300 Axis

The aging liver is affected by several disorders, including steatosis, that can lead to a decline of liver functions. Here, we present evidence that the cdk4-C/EBPα-p300 axis is a critical regulator of age-associated disorders, including steatosis. We found that patients with non-alcoholic fatty liver disease (NAFLD) have increased levels of cdk4 and that cdk4-resistant C/EBPα-S193A mice do not develop hepatic steatosis with advancing age. Underlying mechanisms include a block in C/EBPα activation and subsequent failure in activation of enzymes involved in the development of NAFLD. Inhibition of cdk4 in aged wild-type (WT) mice by a specific cdk4 inhibitor, PD-0332991, reduces C/EBPα-p300 complexes and eliminates hepatic steatosis. Moreover, the inhibition of cdk4 in aged mice reverses many age-related disorders. Mechanisms of correction include elimination of cellular senescence and alterations in the chromatin structure of hepatocytes. Thus, the inhibition of cdk4 might be considered as a therapeutic approach to correct age-associated liver disorders.

Nguyen et al. show that nuclear elevation of cdk4 leads to age-associated disorders, such as hepatic steatosis, and to age-dependent decline of liver functions and morphology. Elevation of cdk4 changes multiple molecular aspects of liver biology. Inhibition of cdk4 in old mice eliminates hepatic steatosis and corrects age-associated liver disorders.

Clinical research in older adults with hematologic malignancies: Opportunities for alignment in the Veterans Affairs

Management of hematologic malignancies in older patients is complex and, with recent and anticipated trends in demographics, increasingly common. As a large, nationally integrated medical system the Veterans Affairs has the potential to lead in research to benefit these patients. In this review we describe the evolving treatment paradigms of hematologic malignancies and how they are best fit with older patients through comprehensive evaluation of key vulnerabilities. We also discuss optimization of supportive care and navigation services to target identified risks and challenges aimed at ameliorating the patient's burden of cancer and treatment. Lastly, we discuss opportunities in design of prospective clinical trials to better align with real-world cases, thereby expanding enrollment of and applicability to older patients with hematologic malignancies.

Cancer-driven changes link T cell frequency to muscle strength in people with cancer: a pilot study

BACKGROUND

Tumour growth can promote the loss of muscle mass and function. This is particularly disturbing because overall survival is significantly reduced in people with weaker and smaller skeletal muscle. The risk of cancer is also greater in people who are immune deficient. Muscle wasting in mice with cancer can be inhibited by infusion of CD4⁺ precursor T cells that restore balanced ratios of naïve, memory, and regulatory T cells. These data are consistent with the hypothesis that stronger anti-cancer T cell immunity leads to improved muscle mass and function. As a first step to testing this hypothesis, we determined whether levels of circulating T cell subsets correlate with levels of muscle strength in people with cancer.

METHODS

The frequency of circulating CD4⁺ and CD8⁺ naïve, memory, and regulatory T cell subsets was quantified in 11 men with gastrointestinal cancer (aged 59.3 ± 10.1 years) and nine men without cancer (aged 60 ± 13 years), using flow cytometry. T cell marker expression was determined using real-time PCR and western blot analyses in whole blood and peripheral blood mononuclear cells. Handgrip strength, one-repetition maximum chest press, and knee extension tests were used to determine muscle strength. Performance was determined using a stair climb test. Body composition was determined using dual-energy X-ray absorptiometry scan. The Karnofsky and ECOG scales were used to assess functional impairment. Correlations between frequencies of cell subsets with strength, performance, and body composition were determined using regression analyses.

RESULTS

Our data show significant correlations between (i) higher frequencies of CD8⁺ naïve (P = 0.02) and effector memory (P = 0.003) T cells and lower frequencies of CD8⁺ central memory T cells (P = 0.002) with stronger handgrip strength, (ii) lower frequency of regulatory cells with greater lean mass index (P = 0.04), (iii) lower frequency of CD8⁺ T cells that express CD95 with greater stair climb power (P = 0.003), (iv) higher frequency of T cells that co-express CD197 and CD45RA and greater one-repetition maximum knee extension strength (P = 0.008), and (iv) higher expression of CD4 in whole blood with greater functional impairment (P = 0.004) in people with cancer.

CONCLUSIONS

We have identified significant correlations between levels of T cell populations and muscle strength, performance, and body composition in people with cancer. These data justify a follow-up study with a larger cohort to test the validity of the findings.

Abstract 5044: Prostate adenocarcinoma incidence and risk factors in Veterans with well controlled HIV infection

(a) Although prostate cancer is projected to be one of the most frequently diagnosed cancers in HIV-infected men overall, little is known about its risk in the sub-group with well-controlled HIV-infection.

(b) We performed a retrospective cohort study to determine age-adjusted incidence of prostate adenocarcinoma in HIV-positive male veterans utilizing Veterans Administration (VA) healthcare between 10/01/1999 and 12/31/2016. HIV infection and prostate adenocarcinoma diagnosis as well as related clinical, sociodemographic, and lifestyle risk factors were obtained using extant VA administrative healthcare databases, the VA cancer registry, and augmented prostate cancer diagnosis with direct electronic medical record (EMR) review. We defined well controlled HIV as &gt;60% of time with an undetectable HIV viral load and limited our analyses to those with a minimum of 90 days between HIV and prostate diagnosis, death, their last recorded health care encounter, or study end. We employed time-varying Cox proportional hazard regression models and used backward elimination to identify risk factors associated with incident prostate adenocarcinoma; effects are reported as Hazard ratios (HR) and 95% confidence intervals (CI).

(c) During an average 10.26 years of follow-up, we identified 587 incident prostate adenocarcinomas among our cohort of 19,079 HIV positive men with well-controlled infection (age-adjusted incidence rate [IR] = 83.31 per 100,000-person years, 95% CI: 76.83-90.33); with a significant increasing trend over time. We identified several factors associated with significant increased risk of incident prostate adenocarcinoma, after adjusting for HIV medication use, in our well-controlled HIV-positive cohort including substance abuse (HR=1.68, 95% CI: 1.27-2.24, p=0.0003), age at HIV diagnosis (HR=1.73, 95% CI: 1.25-2.39, p=0.0010), and black race (HR=2.07, 95% CI: 1.58-2.72, p&lt;.0001). History of alcohol abuse (HR=0.54, 95% CI: 0.39-0.75, p=0.0002), longer time with well-controlled infection (HR=0.63, 95% CI: 0.59-0.67, p&lt;.0001), and receiving integrase inhibitors (HR=0.64, 95% CI: 0.45-0.92, p=0.041) were associated with reduced risk. Several risk factors included in the multivariable model, such as PSA testing, testosterone levels, and maximum BMI, were not found to be significantly associated with or protective for prostate cancer.

(d) Further research is needed to confirm our findings and to better identify sub-groups of well-controlled HIV-positive men at greatest increased prostate cancer risk.

Citation Format: Kathryn E. Royse, Jose M. Garcia, Donna L. White, Jennifer R. Kramer, Yongquan Dong, Suchismita Raychaudhury, Peter A. Richardson, Christine Hartman, Elizabeth Y. Chiao. Prostate adenocarcinoma incidence and risk factors in Veterans with well controlled HIV infection [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 5044.

Levels of phthalate acid esters and sex hormones and their possible sources in traffic-patrol policemen in Chongqing

To investigate the correlation between the air phthalate acid ester (PAE) exposure and serum PAE concentration and the effects of PAE exposure on reproductive health among Chongqing traffic-patrol policemen. In 2013, 32 traffic-patrol policemen working in an area with poor air quality in Chongqing and 28 traffic-patrol policemen working in an area with good air quality were selected. Their blood levels of 14 PAEs and six reproductive hormones were determined. Air samples were collected from four traffic-patrol platforms. The concentrations of 14 PAEs in the air samples were evaluated. All 14 PAEs were detected in the blood samples. The concentrations of seven PAEs in the total suspended particulate, namely, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, bis (2-ethox-yethyl) phthalate, dihexyl phthalate, benzyl butyl phthalate, and bis (2-n-butoxyethyl) phthalate, were positively and significantly associated with the blood levels of these PAEs in the participants. All the sex hormone levels measured here were significantly different between the participants from the two areas. The PAE concentrations in the blood samples were correlated with the reproductive hormone levels in the participants. Air PAE pollution may be a major source of PAE exposure in the traffic-patrol policemen of Chongqing.

Selective Serotonin Reuptake Inhibitors Reduce Longitudinal Growth in Risperidone-Treated Boys

OBJECTIVES

To examine whether selective serotonin reuptake inhibitors (SSRIs) inhibit longitudinal growth in children and adolescents, particularly in the early stages of puberty, using a sample of convenience comprising risperidone-treated boys.

STUDY DESIGN

Data from four clinic-based studies in risperidone-treated 5- to 17-year-old boys with no general medical conditions were combined for this analysis. Anthropometric measurements and psychotropic treatment history were extracted from the medical and pharmacy records. Linear mixed effects regression analyses examined the association between SSRI use and change in age-sex-specific height and body mass index z scores, after adjusting for relevant confounders.

RESULTS

Risperidone-treated boys (n = 267; age: 12.7 ± 2.7 years), 71% of whom had ever taken an SSRI, contributed to the analysis. After adjusting for age, psychostimulant and antipsychotic use, and time in the study, both the duration of SSRI use as well as the cumulative dose were inversely associated with height z score after age 11 years (P < .0001). After adjusting for baseline height, duration of SSRI use was most strongly inversely associated with height z score in Tanner stages 3 and 4 boys who took SSRIs continuously (r = -0.69, P < .009). No association was observed with body mass index z score.

CONCLUSIONS

In risperidone-treated boys, SSRI use is associated with reduced longitudinal growth, particularly in those undergoing puberty. Whether adult height or other metabolic or psychological outcomes are affected remains to be determined.

Anti-Hypertensive Medication Use, Soluble Receptor for Glycation End Products and Risk of Pancreatic Cancer in the Women's Health Initiative Study

Pancreatic cancer is the fourth leading cause of cancer death. Soluble receptor for glycation end products (sRAGE), which is modulated by anti-hypertensive (HT) medications, has been inversely associated with pancreatic cancer. However, the association between commonly used anti-HT medications and risk of pancreatic cancer is unknown. A total of 145,551 postmenopausal women from the Women Health Initiative (WHI) Study were included in analysis. Use of angiotensin converting enzyme inhibitors (ACEi), β-blockers, calcium channel blockers (CCBs) and diuretics was ascertained at baseline (1993⁻1998). Baseline sRAGE levels were measured among a subset of 2104 participants using an immunoassay. Multivariable Cox proportional hazard regression model was performed to estimate hazard ratios (HRs) and its 95% confidence intervals (CIs) for pancreatic cancer in association with anti-HT medications. Increased risk of pancreatic cancer was found among users of short-acting CCB (HR = 1.66, 95% CI: 1.20⁻2.28) and long-term (≥3 years) users of short-acting CCB (HR = 2.07, 95% CI: 1.42⁻3.02) compared to users of other anti-HT medications. Average sRAGE levels were lower in short-acting CCB users than users of other anti-HT medications (1173 versus 1454 pg/mL, p = 0.038). Non-statistically significant reduced risk of pancreatic cancer was found among users of β-blockers (HR = 0.80, 95% CI: 0.60⁻1.07). Average sRAGE levels were higher in β-blockers users than users of other anti-HT medications (1692 versus 1454 pg/mL, p > 0.05). Future studies are warranted to confirm these findings and elucidate potential mechanisms by which anti-HT medications influence development of pancreatic cancer.

Macimorelin as a Diagnostic Test for Adult GH Deficiency

PURPOSE

The diagnosis of adult GH deficiency (AGHD) is challenging and often requires confirmation with a GH stimulation test (GHST). The insulin tolerance test (ITT) is considered the reference standard GHST but is labor intensive, can cause severe hypoglycemia, and is contraindicated for certain patients. Macimorelin, an orally active GH secretagogue, could be used to diagnose AGHD by measuring stimulated GH levels after an oral dose.

MATERIALS AND METHODS

The present multicenter, open-label, randomized, two-way crossover trial was designed to validate the efficacy and safety of single-dose oral macimorelin for AGHD diagnosis compared with the ITT. Subjects with high (n = 38), intermediate (n = 37), and low (n = 39) likelihood for AGHD and healthy, matched controls (n = 25) were included in the efficacy analysis.

RESULTS

After the first test, 99% of macimorelin tests and 82% of ITTs were evaluable. Using GH cutoff levels of 2.8 ng/mL for macimorelin and 5.1 ng/mL for ITTs, the negative agreement was 95.38% (95% CI, 87% to 99%), the positive agreement was 74.32% (95% CI, 63% to 84%), sensitivity was 87%, and specificity was 96%. On retesting, the reproducibility was 97% for macimorelin (n = 33). In post hoc analyses, a GH cutoff of 5.1 ng/mL for both tests resulted in 94% (95% CI, 85% to 98%) negative agreement, 82% (95% CI, 72% to 90%) positive agreement, 92% sensitivity, and 96% specificity. No serious adverse events were reported for macimorelin.

CONCLUSIONS

Oral macimorelin is a simple, well-tolerated, reproducible, and safe diagnostic test for AGHD with accuracy comparable to that of the ITT. A GH cutoff of 5.1 ng/mL for the macimorelin test provides an excellent balance between sensitivity and specificity.

The habenula as a novel link between the homeostatic and hedonic pathways in cancer-associated weight loss: a pilot study

BACKGROUND

Little is known about the brain mechanisms underlying cancer-associated weight loss (C-WL) in humans despite this condition negatively affecting their quality of life and survival. We tested the hypothesis that patients with C-WL have abnormal connectivity in homeostatic and hedonic brain pathways together with altered brain activity during food reward.

METHODS

In 12 patients with cancer and 12 healthy controls, resting-state functional connectivity (RSFC, resting brain activity observed through changes in blood flow in the brain which creates a blood oxygen level-dependent signal that can be measured using functional magnetic resonance imaging) was used to compare three brain regions hypothesized to play a role in C-WL: the hypothalamus (homeostatic), the nucleus accumbens (hedonic), and the habenula (an important regulator of reward). In addition, the brain reward response to juice was studied. Participants included 12 patients with histological diagnosis of incurable cancer (solid tumours), a European Cooperative Oncology Group performance status of 0-2, and a ≥5% involuntary body weight loss from pre-illness over the previous 6 months and 12 non-cancer controls matched for age, sex, and race. RSFC between the hypothalamus, nucleus accumbens, and habenula and brain striatum activity as measured by functional MRI during juice reward delivery events were the main outcome measures.

RESULTS

After adjusting for BMI and compared with matched controls, patients with C-WL were found to have reduced RSFC between the habenula and hypothalamus (P = 0.04) and between the habenula and nucleus accumbens (P = 0.014). Patients with C-WL also had reduced juice reward responses in the striatum compared with controls.

CONCLUSIONS

In patients with C-WL, reduced connectivity between both homeostatic and hedonic brain regions and the habenula and reduced juice reward were observed. Further research is needed to establish the relevance of the habenula and striatum in C-WL.

Use of growth hormone, IGF-I, and insulin for anabolic purpose: Pharmacological basis, methods of detection, and adverse effects

Hormones with anabolic properties such as growth hormone (GH), insulin-like growth factor-1 (IGF-I), and insulin are commonly abused among professional and recreational athletes to enhance physical ability. Performance enhancing drugs (PEDs) such as these are also commonly used by recreational athletes to improve body aesthetics. The perception of increased muscle mass due to supraphysiologic hormone supplementation, or doping, is widespread among PED users despite a paucity of evidence-based data in humans. Even still, athletes will continue to abuse PEDs in hopes of replicating anecdotal results. It is important to educate the general public and potential treating physicians of the risks of PED use, including the dangers of polypharmacy and substance dependence. It will also be important for the research community to address the common challenges associated with studying PED use such as the ethical considerations of PED administration, the general reticence of the PED-using community to volunteer information, and the constant need to improve or create new detection methods as athletes continually attempt to circumvent current methods. This review highlights the anabolic mechanisms and suggestive data implicating GH, IGF-I, and insulin for use as PEDs, the specific detection methods with cutoff ranges that may be utilized to diagnose abuse of each substance, and their respective side effects.