VHL: Trends and Insight into a Multi-Modality, Interdisciplinary Approach for Management of Central Nervous System Hemangioblastoma

Von Hippel-Lindau (VHL) is a multi-system disease which results in significant morbidity from central nervous system (CNS) involvement as well as ocular, renal and neuro-endocrine effects. Haemangioblastomas of the CNS present a number of challenges. The natural history of these lesions is varied, as is the size and location within the CNS. Whilst surgery is considered the mainstay of treatment and best chance at curing these lesions, this is also often associated with significant risks due to the anatomical location of these lesions, most commonly the posterior fossa and spinal cord.We review the literature and describe our experience across two separate European VHL referral centres. Alternative treatment options and combined modalities are increasingly being used in the context of managing CNS haemangioblastomas. We analyse the increasing use of stereotactic radiosurgery and the evolution of medical treatments as potential future adjuncts to surgery. The availability of multiple modalities in our armamentarium is essential in tailoring a personalised treatment approach to these patients. Owing to the multi-systemic nature of the disease, in our experience, managing the care of patients with VHL is best delivered using an interdisciplinary approach utilising multiple specialties and adopting an individually tailored holistic approach.

Triplet transfer from PbS quantum dots to tetracene ligands: is faster always better?

Quantum dot-organic semiconductor hybrid materials are gaining increasing attention as spin mixers for applications ranging from solar harvesting to spin memories. Triplet energy transfer between the inorganic quantum dot (QD) and organic semiconductor is a key step to understand in order to develop these applications. Here we report on the triplet energy transfer from PbS QDs to four energetically and structurally similar tetracene ligands. Even with similar ligands we find that the triplet energy transfer dynamics can vary significantly. For TIPS-tetracene derivatives with carboxylic acid, acetic acid and methanethiol anchoring groups on the short pro-cata side we find that triplet transfer occurs through a stepwise process, mediated via a surface state, whereas for monosubstituted TIPS-tetracene derivative 5-(4-benzoic acid)-12-triisopropylsilylethynyl tetracene (BAT) triplet transfer occurs directly, albeit slower, via a Dexter exchange mechanism. Even though triplet transfer is slower with BAT the overall yield is greater, as determined from upconverted emission using rubrene emitters. This work highlights that the surface-mediated transfer mechanism is plagued with parasitic loss pathways and that materials with direct Dexter-like triplet transfer are preferred for high-efficiency applications.

LBMON299 Aldosterone Production Is Regulated By Gap Junctions In Human Adrenal Cells

 

Aldosterone plays a critical role in blood pressure regulation via the renin-angiotensin-aldosterone system. Autonomous production of aldosterone, primary aldosteronism (PA), is the commonest curable cause of hypertension worldwide. Two cell types in the adrenal cortex produce aldosterone: zona glomerulosa (ZG) cells and aldosterone producing nodules (APN), and in cells of aldosterone producing adenomas (APA). Adrenal cortex cells undergo phenotypic metamorphosis as they migrate from the subcapsular region, centripetally, towards the corticomedullary junction, changing from aldosterone- to cortisol- producing cells as they go. Gap junctions (GJs) are specialised channels of cytoplasmic communication between cells, permitting the regulated transfer of substrates. Loss-of-function mutations in the CADM1 gene, which affects GJ protein CX43, have been found in APAs, implicating CX43 in aldosterone regulation. This study aims to demonstrate the dysregulation of aldosterone production by CX43 inhibition in human adrenal cell line, H295R, and elucidate GJ distribution in human adrenal cortex.

Methodology

H295R cells were treated with 1×10-8M angiotensin II and connexin mimetic GJ inhibitor, GAP27, at 0µM, 25µM, 83µM and 250µM. Immunofluorescence (IF) was used to identify the abundance of CX43 in different cell types of the adrenal cortex, performed on ex-vivo para-APA adrenal tissue, using antibodies against CX43 (GJA1), colocalised with markers of aldosterone-producing cells (aldosterone synthase, CYP11B2), cells of the zona glomerulosa (ZG) (VSNL1, and DAB2) and zona fasciculata (ZF) (CYP7A1).

Results

Inhibition of CX43 with Gap27 results in a dose-dependent increase in CYP11B2 mRNA expression and aldosterone production. At the highest concentration of 250µM GAP27, CYP11B2 mRNA expression increased by 133-fold (p=<0. 00001) and aldosterone production by 29-fold (p=0. 0006). IF studies demonstrate a crescendo gradient of CX43 in a centripetal direction from cells of APN to ZF. The abundance was lowest in aldosterone-producing APN cells, moderate in non-aldosterone-producing ZG cells and highest in cortisol-producing ZF cells. GJ distribution was pan-membranous in ZF, but, where present, mostly cytoplasmic in APN. Evidence of recent active communication, in the form of annular gap junctions (AJG), was present in all three cell types.

Conclusion

The CX43 inhibition-induced upregulation of CYP11B2 expression and aldosterone synthesis indicates that it has an important regulatory role in physiological aldosterone production via CYP11B2 expression. The distribution of CX43 in adrenal tissue suggests its transport substrate not only regulates aldosterone synthesis, but also in adrenal cortex cell phenotypic metamorphosis/migration. Future work will investigate the substrate of CX43 in adrenal cells and its possible effect on adrenal cell phenotype.

Presentation: Monday, June 13, 2022 12:30 p.m. - 2:30 p.m.

A Comparison of the Blood Glucose, Growth Hormone, and Cortisol Responses to Two Doses of Insulin (0.15 U/kg vs. 0.10 U/kg) in the Insulin Tolerance Test: A Single-Centre Audit of 174 Cases

OBJECTIVE

The insulin tolerance test (ITT) is the gold standard endocrine test used to assess the integrity of the growth hormone (GH) and cortisol axes. The ITT has potential risks, and severe hypoglycaemia may necessitate intravenous glucose rescue. There is no clear consensus as to the optimal insulin dose for the ITT. Therefore, we sought to compare the standard dose (0.15 U/kg) and a low-dose ITT (0.1 U/kg).

DESIGN

Single-centre audit of ITT data (2012-2021). Patients and Measurements. Patients who underwent an ITT to assess possible GH deficiency/adrenal insufficiency were included. Glucose, GH, and cortisol were measured at baseline and 30, 45, 60, 90, and 120 minutes following I.V. insulin bolus (0.15 U/kg or 0.10 U/kg).

RESULTS

Of the ITTs performed, only 3/177 (1.7%) did not achieve adequate hypoglycaemia (≤2.2 mmol/L) with a single insulin dose. In total, 174 patients (43.5 ± 12.1 yrs, mean ± standard deviation) were included for analysis (0.15 U/kg: n = 113, 0.10 U/kg: n = 61). All 174 subjects had adequate hypoglycaemia regardless of baseline fasting blood glucose level or insulin dose. Neither nadir glucose nor glucose delta (i.e., baseline minus nadir) differed between insulin doses. Trends in both cortisol and GH responses over time were similar between groups, and a greater proportion of patients receiving the standard dose had an adequate cortisol response (77/106 (72.6%) vs. 32/60 (53.3%), p=0.01). The rates of glucose rescue did not differ in a subset of 79 patients, with on-demand glucose rescue in 4/35 (11%) for the standard dose and 2/44 (5%) for the low dose (p=0.25).

CONCLUSIONS

Our results suggest that the low-dose ITT produces comparable glucose, cortisol, and GH responses to the higher dose. Given the risks associated with hypoglycaemia, the low dose appears to be preferable to the standard dose ITT in most circumstances.

Sub-millimeter endoscope demonstrates feasibility of in vivo reflectance imaging, fluorescence imaging, and cell collection in the fallopian tubes

SIGNIFICANCE

Most cases of high-grade serous ovarian carcinoma originate as serous tubal intraepithelial carcinoma (STIC) lesions in the fallopian tube epithelium (FTE), enabling early endoscopic detection.

AIM

The cell-acquiring fallopian endoscope (CAFE) was built to meet requirements for locating potentially pathological tissue indicated by an alteration in autofluorescence or presence of a targeted fluorophore. A channel was included for directed scrape biopsy of cells from regions of interest.

APPROACH

Imaging resolution and fluorescence sensitivity were measured using a standard resolution target and fluorescence standards, respectively. A prototype was tested in ex vivo tissue, and collected cells were counted and processed.

RESULTS

Measured imaging resolution was 88  μm at a 5-mm distance, and full field of view was ∼45  deg in air. Reflectance and fluorescence images in ex vivo porcine reproductive tracts were captured, and fit through human tracts was verified. Hemocytometry counts showed that on the order of 105  cells per scrape biopsy could be collected from ex vivo porcine tissue.

CONCLUSIONS

All requirements for viewing STIC in the FTE were met, and collected cell counts exceeded input requirements for relevant analyses. Our benchtop findings suggest the potential utility of the CAFE device for in vivo imaging and cell collection in future clinical trials.

Somatic Mutations of GNA11 and GNAQ in CTNNB1-Mutant Aldosterone-Producing Adenomas Increases Aldosterone and Aldosterone Synthase (CYP11B2)

Most aldosterone-producing adenomas (APA) have gain-of-function somatic mutations of ion channels or transporters. However, their frequency in aldosterone-producing cell-clusters of normal adrenals suggests the existence of co-driver mutations which influence the development or phenotype of APAs.

Gain-of-function mutations in both CTNNB1 and GNA11 were found by whole exome sequencing in 3 of 41 APAs from a UK/Irish cohort. Targeted sequencing for exon 3 mutations of CTNNB1 and p.Gln209 mutations of either GNA11 or closely homologous GNAQ confirmed these and 7 further double mutant APAs in this discovery cohort. The presence of GNA11/Q p.Gln209 mutations in CTNNB1 mutant APAs were replicated in 2 cohorts from France (n=14) and Sweden (n=3). In total, 16 (59%) of the 27 CTNNB1 mutant APAs investigated had a mutation at p.Gln209 of GNA11 (n=11) or GNAQ (n=5). Interestingly, CTNNB1-mutant APAs were more commonly present in women (23/27), and of these, those with GNA11/Q mutations were all women except for a pubertal boy. To also note, 9 of 10 of the UK/Irish double mutant APAs in the discovery cohort presented in puberty, pregnancy, or menopause.

Mutation of p.Gln209, or homologous p.Gln in GNAS, GNA12-14, impair hydrogen bonds between G-protein α and β subunits. Transfection of H295R cells, an immortalised adrenocortical cell line heterozygous for the p.Ser45Pro mutation of CTNNB1 but wild-type for GNA11-14/Q/S, by each of the GNA11/Q mutations increased aldosterone secretion and CYP11B2 expression (encoding aldosterone synthase) by 1.93-6.1-fold and 8.0-9.8-fold respectively, compared to vector or wild-type -transfected cells. In ZG, GNA11/Q mediate the aldosterone response to angiotensin II, via stimulation of intracellular Ca2+ release by inositol trisphosphate. In the mutant-transfected cells, the stimulatory effect of angiotensin II 10 nM was retained. In order to determine whether the p.Gln209 mutations stimulate aldosterone production even in the absence of CTNNB1 activation, the transfections of H295R cells were repeated after either 24-h treatment with the CTNNB1 inhibitor, ICG-001, or silencing of CTNNB1 using the ONTARGETplus SMARTpool SiRNAs (Dharmacon). Both interventions reduced the aldosterone production relative to vehicle/control-treated cells; however neither ICG-001 nor silencing of CTNNB1 blunted the fold-increase in aldosterone secretion seen in mutant-transfected cells compared to wild-type.

In summary, we report the discovery of gain-of-function mutations of the G-protein, GNA11, or its close homologue, GNAQ, in multiple APAs which majority presented during periods of high LH/HCG. To date, the mutation is always residue p.Gln209, and associated with a gain-of-function mutation of CTNNB1. These GNA11/Q p.Gln209 mutations increase aldosterone and CYP11B2 production both in the presence and in the absence of CTNNB1 activation.

CTNNB1-Mutant Aldosterone-Producing Adenomas With Somatic Mutations of GNA11/GNAQ Have Distinct Phenotype and Genotype

Background: We report (this meeting) somatic mutation of GNA11/Q in CTNNB1-mutant APAs. The recurrent co-driver mutation causes reversible hypertension in puberty, pregnancy, or menopause. We have investigated the molecular mechanism of this association. Methods: Gene expression profiles in 3 double mutant APAs were studied by unsupervised hierarchical clustering analysis and enrichment analysis of 362 differentially expressed genes and validated by qPCR, IFC and IHC in 10 double mutant APAs or transfected primary adrenal cells. Multiple region biopsies were performed in 7 adrenals adjacent to double-mutant APAs and 4 APAs with KCNJ5 or CACNA1D mutations. The findings of APA mutations in adjacent adrenals were replicated in each case by ddPCR ± NGS. Results: Unsupervised hierarchical clustering analysis showed clustering of the double-mutant APAs, and a high proportion of genes were many-fold upregulated compared to other APAs. LHCGR, TMEM132E, DKK1, C9orf84, FAP, GNRHR and MPP3 are among the genes with high expression. A small number of genes are down-regulated in the double-mutant APAs, including CYP11B1. qPCR confirmed an average of ~10 to 1000-fold higher expression of the hallmark genes in double-mutants. Enrichment analysis showed significant enrichment of features or terms concerned with cell junction and cell adhesion (P<10^–8). IFC confirmed LHCGR intensity was 31–144 fold higher in primary adrenal cells with GNA11-p.Gln209Pro transfection and high CTNNB1 intensity. LHCGR intensity was qualitatively and quantitatively associated with immunofluorescence for CTNNB1. IHC of double-mutant APAs showed absent CYP11B1 but strong staining of CYP11B2. qPCR confirmed a lower CYP11B1/CYP11B2 ratio and a higher LHCGR expression (P<10^–3, both). IHC confirmed LHCGR positivity in double-mutant APAs but distribution varied both within and between cells. Adjacent ZG was hyperplastic, with absence of both CYP11B1 and CYP11B2 staining, but weak/moderate staining for LHCGR. The same GNA11 ± CTNNB1 somatic mutations were detected in multiple regions of the adjacent adrenals to 3 double mutant APAs. qPCR of hallmark APA genes differed from the APAs. High concordance between ddPCR, NGS and Sanger sequencing of the findings of APA mutations in adjacent adrenals when analysed in the same sample. No mutations were found in 4 adrenals adjacent to APAs with KCNJ5 or CACNA1D mutations, nor in other 4 adrenals adjacent to double-mutant APAs. Conclusions: Patients harboring APAs with somatic mutations in both GNA11/GNAQ Q209 and CTNNB1 have distinct phenotype in both the APAs and their adjacent adrenals. Same GNA11 ± CTNNB1 somatic mutations were found in the adjacent adrenals to double mutant APAs. We infer that a double-hit within related pathways is more likely than a single-hit to cause large increases in expression of LHCGR, and of other genes which may influence clinical presentation.

Current Management and Outcome of Pregnancies in Women With Adrenal Insufficiency: Experience from a Multicenter Survey

CONTEXT

Appropriate management of adrenal insufficiency (AI) in pregnancy can be challenging due to the rarity of the disease and lack of evidence-based recommendations to guide glucocorticoid and mineralocorticoid dosage adjustment.

OBJECTIVE

Multicenter survey on current clinical approaches in managing AI during pregnancy.

DESIGN

Retrospective anonymized data collection from 19 international centers from 2013 to 2019.

SETTING AND PATIENTS

128 pregnancies in 113 women with different causes of AI: Addison disease (44%), secondary AI (25%), congenital adrenal hyperplasia (25%), and acquired AI due to bilateral adrenalectomy (6%).

RESULTS

Hydrocortisone (HC) was the most commonly used glucocorticoid in 83% (97/117) of pregnancies. Glucocorticoid dosage was increased at any time during pregnancy in 73/128 (57%) of cases. In these cases, the difference in the daily dose of HC equivalent between baseline and the third trimester was 8.6 ± 5.4 (range 1-30) mg. Fludrocortisone dosage was increased in fewer cases (7/54 during the first trimester, 9/64 during the second trimester, and 9/62 cases during the third trimester). Overall, an adrenal crisis was reported in 9/128 (7%) pregnancies. Cesarean section was the most frequent mode of delivery at 58% (69/118). Fetal complications were reported in 3/120 (3%) and minor maternal complications in 15/120 (13%) pregnancies without fatal outcomes.

CONCLUSIONS

This survey confirms good maternal and fetal outcome in women with AI managed in specialized endocrine centers. An emphasis on careful endocrine follow-up and repeated patient education is likely to have reduced the risk of adrenal crisis and resulted in positive outcomes.

SAT-224 Recurrent Co-Driver Mutation in CTNNB1-Mutant Aldosterone-producing Adenomas (APA), Causing Reversible Hypertension in Puberty, Pregnancy or Menopause

Background: Three patients with a syndrome of LH/HCG-activated primary aldosteronism in pregnancy or menopause carrying somatic CTNNB1 mutations were reported four years ago (Teo et al. NEJM 2015). This proved but half the story. Diagnosis of an APA in a 12-year old boy with severe hypertension revealed an apparently essential co-driver mutation. Methods: WES of tumour and blood was performed in the pubertal boy. Candidate genes were Sanger sequenced in other APAs from GB/Ireland, and France with known or suspected CTNNB1 mutations. LHCGR, GNRHR and CYP11B2 expression were measured in all available patients’ APAs and the adjacent adrenal gland (AAG) by RT-PCR. RNA and gDNA from the zona glomerulosa (ZG) of the proband’s AAG were collected by laser capture microdissection for Sanger sequencing of GNA11 and CTNNB1. Function of mutant genes was assessed by measurement of aldosterone production and LHCGR expression by immunofluorescence (IFC) in NCI-H295R adrenocortical cells and primary human APA cells. Results: The proband’s APA contained a p.(S45F) somatic mutation in CTNNB1, and a p.(Q209P) somatic mutation of the GTPase-activating residue (Q209) in GNA11. Mutations of Q209, to P or H, were also found in six other GB/Irish patients with previously identified mutations of CTNNB1 (S33C, G34R, T41A, S45F, or S45P). All seven patients remain normotensive 2-12 years post-adrenalectomy, including some with long-standing pre-operative hypertension. Four of the 13 French patients with CTNNB1 exon 3 mutant APAs have somatic mutation of Q209 of either GNA11 (n=3) or GNAQ. In comparison with their own AAG, the GB/Irish double mutant APAs showed an increase in expression of LHCGR, CYP11B2 and GNRHR by 32-166, 158-18980, and 1174-6642 fold, respectively. All four French double-mutants had >10 fold higher LHCGR than APAs with single mutations of CTNNB1 or other genes. Hyperplasia of ZG was observed in the ZG of the boy’s AAG but no APCC was detected. Homozygous or heterozygous Q209P mutation of GNA11 was detected in multiple ZG samples in RNA and/or gDNA but WT in CTNNB1 exon 3. H295R cells (CTNNB1 S45P) were GNA11 WT. Overexpression of GNA11 Q209 mutation increased aldosterone secretion to 465% of GNA11 WT overexpressing cells (n=6, P<0.001) and CYP11B2 expression was also increased several-fold. Smaller increases were seen in primary human adrenal cells after double-transfection by GNA11 and CTNNB1 mutants (n=3, P<0.001). This also caused membrane expression of LHCGR, visualised by IFC. Conclusions: APAs with double mutation of GNA11/GNAQ Q209 and CTNNB1 have a distinct phenotype, in which hypertension is triggered by high LH or HCG, and cured in all cases by adrenalectomy. GNA11/Q mediates the aldosterone response to ANGII, and the Q209 codon is analogous to the Q227 of GNAS, mutated in McCune Albright. Mosaicism for GNA11 may cause ZG hyperplasia.

OR34-07 Prospective Multicentre Study Comparing 11C-metomidate PET CT with Adrenal Vein Sampling (AVS) in the Detection of Unilateral Aldosterone-Producing Adenomas (APAs)

Approximately 50% of Primary Aldosteronism (PA) cases are unilateral, potentially curable by adrenalectomy. However far fewer patients progress to surgery, partly due to difficulties in identifying unilateral disease. AVS is the current criterion standard method for lateralisation. However it is an invasive procedure, technically difficult to perform, and only available in few specialist centres. MATCH is a prospective, multicentre study comparing the diagnostic accuracy of AVS with 11C-metomidate PET-CT, a non-invasive functional scan (ClinicalTrials.gov Identifier NCT02945904).

Patients fulfilling Endocrine Society criteria for PA undergo both investigations in random order. At a multidisciplinary meeting PET-CT results are scored first, followed by AVS. Patients are offered surgery if one or both investigations indicate unilateral disease. Each investigation will be re-scored by an independent, blinded endpoints committee, without knowledge of other investigations or outcomes in the same patient. Hierarchical primary outcomes are the change in aldosterone renin ratio (ARR) and average home SBP readings. If no superiority is observed for either investigation, non-inferiority of PET-CT will be tested. MATCH is powered to detect 25% superiority, or non-inferiority within a margin of 18%. Factors predicting cure will be assessed as secondary outcomes. These include BP response to aldosterone antagonists, correlation of standardised uptake value (SUV) max ratio of adenoma to adjacent normal adrenal, and phenotyping / genotyping of tumours.

Target recruitment of 140 patients has been achieved. Interesting observations to date include a high prevalence of hypokalaemia (73%), reflective of our referral base and inclusion criteria. The surgery rate is also high at 66%, consistent with finding frequent patients in whom only one investigation yields a positive result. The following case illustrates such a patient. A slim 45-year-old lady with PA and failed ONDST had inconclusive AVS (selectivity index in right adrenal vein 2.6). PET-CT revealed a 29mm metomidate-avid left adrenal nodule (SUVmax ratio 1.52, &gt;1.25 suggestive of unilateral disease). Left adrenalectomy was recommended based on PET-CT, and achieved biochemical and clinical cure. However she required hydrocortisone replacement for 14 months. Her relatively low right adrenal vein cortisol, despite successful cannulation, was attributed to contralateral suppression by co-secretion of cortisol from her adenoma. This was confirmed by finding high CYP11B1 and CYP11B2 mRNA expression in her tumour, typical of a KCNJ5 mutation, confirmed as L168R on Sanger sequencing.

PA is a high risk subset of hypertension. Under-treatment has serious public health consequences. 11C-Metomidate PET CT has the potential to simplify the investigation pathway and allow more patients to receive potentially curable treatment.

OR09-05 Expression of SLC35F1 in the Plasma Membrane of Cells of Aldosterone Producing Cell Clusters (APCCs) and Its Possible Role in Aldosterone Synthesis

Background Genetic mutations and histological appearances suggest that APCCs are precursors to some aldosterone producing adenomas (APA). They are hypothesised to contribute to post-operative non-cure and recurrence of primary aldosteronism (PA) but are currently undetectable pre-operatively. SLC35F1 is a possible nucleotide sugar transporter. On microarray it is highly expressed in APCCs, but not in the rest of the adrenal cortex (1). Our aim was to investigate the role of SLC35F1 in APCCs, determine its subcellular localisation and establish whether expression is consistent with pathological APCC subtypes (as suggested by recent evidence from in situ metabolomic studies (2)). Methods Comparative bioinformatic analysis of the SLC35F1 amino acid sequence was carried out. Ex vivo 4uM adrenal sections, from 6 PA patients in the MATCH study, were stained on serial sections with anti-CYP11B2 (Gomez-Sanchez) or anti-SLC35F1 (Novus NBP1-86755). In vitro, H295R cells were transfected with SLC35F1 cDNA. Subcellular localisation of SLC35F1-GFP was studied by comparison to organelle markers (golgin 97, RAB11, wheat germ agglutinin, calnexin and Tom20) using confocal microscopy. Overexpression and siRNA knock-down in H295R cells was correlated to aldosterone production. Results SLC35F1 is a decamembrane-spanning transporter molecule predicted to have a negatively charged pocket in the substrate binding site, implying a transport substrate with a positive charge. Strong staining of CYP11B2 in clusters of cells in adrenal cortex, consistent with APCCs, were present in all six adrenal glands (25 APCCs). Serial sections showed specific SLC35F1 staining of APCCs, in cytoplasm and plasma membrane. SLC35F1 staining was absent from normal cortex. 12 APCCs (48%) were SLC35F1-negative. Visualisation of transiently expressed SLC35F1 demonstrated localisation to the endoplasmic reticulum in H295R cells (Pearson’s coefficient r=0.758) with no plasma membrane localisation (r=-0.07). Preliminary transfection data suggest direct involvement in aldosterone production. Conclusions Expression of SLC35F1 in the plasma membrane and cytosol of APCC cells supports a role in pathological aldosterone production by APCCs. The inferred transport substrate of SLC35F1 is the NAD(P)(H) precursor, nicotinamide riboside, a positively-charged nucleotide sugar. If confirmed, the essential requirement for NAD(P)H in steroidogenesis, and heterogeneity of SLC35F1-staining in APCCs, is consistent with a metabolically active, possibly pathological, subtype of APCCs. Detection of SLC35F1 in vivo may therefore facilitate sub-classification of PA patients.

1). Nishimoto et. al. PNAS. 2015 Aug 18;112(33):E4591-9. 2). Murakami et. al. 2019 Hypertension. In press.

SAT-546 Endoscopic Ultrasound-Guided Radiofrequency Ablation (EUS-RFA) as an Alternative to Adrenalectomy for the Treatment of Aldosterone-Producing Adenomas (APAs)

Primary Aldosteronism (PA) carries significant cardiometabolic risk, over and above those attributable to hypertension alone. The Endocrine Society guidelines recommend adrenalectomy in those with unilateral disease. However surgery is likely to become unsustainable in public healthcare systems as more patients are diagnosed with PA. Already, surgery may not be feasible in some patients due to co-morbidities, others are reluctant to have the whole adrenal gland removed when excess aldosterone can be localised to small APA(s) in 1 gland.

The FABULAS Study explores if EUS-RFA is a safe alternative to left-sided adrenalectomy (ClinicalTrials.gov ID NCT03405025). This multicentre phase-1 study comprises 3 groups of 10 patients with proven PA and left APAs. Successive groups have an increasing benefit:risk ratio for surgery. The first 4 ablation procedures are assessed by an independent safety committee before progression into the next, overlapping group. The primary outcomes are safety and feasibility of EUS-RFA. Safety is assessed throughout the study, including measures of intra-procedure adrenomedullary activation. Efficacy is evaluated by biochemistry, home / clinic BPs, and quantitative ¹¹C-metomidate PET-CT at baseline and 6 months post-ablation.

RFA is performed using a Starmed catheter, small enough to pass through a 19-gauge needle, through the stomach. Ablation has been performed in 6 patients (median age 63-years). Mean tumour size was 17mm (range 12-36mm). Plasma metanephrine levels remained stable during RFA. 2 adverse events occurred within the first 48hours post-ablation: AF in a patient with known paroxysmal AF, and an episode of pyrexia and raised CRP attributed to tissue infarction. Both events were deemed ‘not unexpected’ by the safety committee. Most patients have benefited clinically post-ablation. This is illustrated by a 65-year-old man with previously uncontrolled hypertension despite 4 antihypertensive medications, including spironolactone. Baseline aldosterone/renin ratio (ARR) was >200 (PA likely if ARR>60). PET CT revealed a 15mm left adrenal nodule with avid metomidate uptake and an SUVmax ratio of 1.92 (SUVmax ratio >1.25 suggestive of unilateral disease). He underwent uneventful EUS-RFA. 6 months post-ablation his ARR has normalised to 26. On repeat PET CT the metomidate avid adenoma is no longer hot, with a drop in both the SUVmax measured over the APA (31 pre-, and 5 post-ablation) and a reduction in the SUVmax ratio to 1.04. Most importantly, his home BP averages 124/83mmHg and he is thrilled to be off all treatment.

Retrospective reports exist of successful percutaneous and retroperitoneal RFA of APAs. FABULAS is the first prospective study, using a minimally invasive, endoscopic route. If proven to be safe and effective EUS-RFA will open the doors for more patients to receive definitive treatment, potentially even those with bilateral disease.

SUN-306 The Interaction Between Thiazide-Associated Hyponatremia and Acute Illness in Hospitalised Patients

Thiazide diuretics, widely used in the management of hypertension, are associated with a five times greater risk of hyponatremia (serum Na <135mmol/L) than in the general population. Hyponatremia in hospitalised patients warrants special consideration since it is associated with increased morbidity and mortality.

The aim of this study was to describe the clinical characteristics and outcomes in acutely ill medical patients with thiazide-associated hyponatremia (TAH).

We performed a retrospective, case control study examining all acute, unselected medical admissions, over a six week period, to The Royal London Hospital. Cases were defined as adults admitted to hospital with TAH (hyponatremia and a history of being prescribed thiazide diuretic pre-admission). Each case was matched by age, gender and degree of hyponatremia to a similar control - admitted with hyponatremia and no pre-admission exposure to thiazide (non-TAH). Clinical characteristics and treatment outcomes were compared between TAH and non-TAH cohorts.

A total of 1,341 consecutive acute medical admissions (49.7% men) were evaluated. Hyponatremia was detected in 240 (17.9%) admissions. Median (±SD) length of stay was longer among patients with hyponatremia compared to normonatremic patients (5.0±12.4 versus 3.0±9.2 days; p=<0.0001). In-hospital mortality was higher in the hyponatremic group (8.8% versus 4.4% p=0.005). Twenty-two cases (11 men) of TAH accounted for 9.2% of patients with hyponatremia. Median age 64±14 years was similar to other patients with hyponatremia 68±20 years. The median admission serum sodium for TAH cases was 131.5 mmol/L (IQR 126.8 - 134) with a discharge serum sodium of 136.5 mmol/L (IQR 133.8 - 139.3). When compared to matched controls, patients with TAH had similar presenting symptoms - most commonly confusion, headache and dizziness. Length of stay among TAH cases was similar to controls; 5.5±5.1 versus 4.0±3.7 days; p=0.24. Mortality (10%) was the same in both groups. Thiazide was withdrawn during admission in 14 (64%) cases.

In conclusion, acute, clinical outcomes for hospitalised patients with TAH are similar to those with comparable degrees of hyponatremia due to other causes.

OR34-04 Efficiency of Adrenal Venous Sampling in the Treatment Choice of Primary Aldosteronism (AVSTAT Study)

BACKGROUND: Adrenal venous sampling (AVS) is strongly recommended for a subtype diagnosis of primary aldosteronism (PA) if adrenalectomy (ADX) is desired by the patient. Given various issues related to AVS such as technical demand, invasive nature, expensive cost and radiation exposure, AVS is expected to lead efficiently to the subtype diagnosis and ADX. Aim: Primary objective was to assess the performance of AVS to determine treatment of PA by investigating the ratio of unilateral disease and rate of ADX following AVS in patients with unilateral disease. Methods: Sixteen major referral centers in ENS@T (n=10) and Japan (n=6) participated in the study. Study period was from 2006 to 2018. Data on total number of PA patients, AVS (total number and number of successful procedures), number of patients with unilateral diseases, and number of patients that underwent ADX were collected by a questionnaire-based survey. In addition, reasons for not proceeding to ADX in patients with a unilateral diagnosis were investigated. The diagnosis of PA was based on the positive case detection and at least one positive result in confirmatory testing. Results: Total number of confirmed PA patients and conducted AVS showed a dramatic increase during the past decade (PA: 1061 pts/ 2006–2011 to 3718 pts/ 2012–2018; AVS: 720/ 2006–2011 to 2448/ 2012–2018). Success rate of AVS was improved from 79.0% (2006–2011) to 92.5% (2012–2018). Both rate of unilateral PA and ADX of successful procedures decreased from 42.7% (2006–2011) to 37.3% (2012–2018) and from 40.8% (2006–2011) to 34.9% (2012–2018), respectively. Of the patients with successful AVS, bilateral disease was diagnosed in 63.5% (1812/2854 pts). Of the unilateral PA patients, 11.9% (125/ 1054 pts) were not subjected to ADX. The rate of the patients not subjected to ADX was significantly higher in Japan than in ENS@T centers both in patients with successful AVS (75.8% vs. 53.4%) and with unilateral disease (19.9% vs. 8.6%). Clinical decision against ADX in unilateral disease was made by the physicians in 33.3%, the patients in 33.3%, and both in 33.3%. Medical factors for Dr.’s decision against ADX in unilateral disease included good blood pressure control, normokalemia, comorbidities (e.g. DM, CKD), non-lateralized CT findings (e.g. no tumor, contralateral tumor), and discordant results among different criteria of AVS.

Conclusions: High prevalence of bilateral disease and change of treatment policy after implementation affected the efficiency of AVS as an essential diagnostic procedure prior to ADX. Development of non-invasive procedures to exclude bilateral PA and more strict indication of AVS are warranted.

Retrospective Database Analysis of Treatment Patterns Among Patients with Pulmonary Arterial Hypertension

INTRODUCTION

Release of the 2015 European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines put increased emphasis on using combination therapy, either as upfront or sequential therapy among patients with pulmonary arterial hypertension (PAH). However, with these recommendations and the therapy advances made in the last several years, little is known on the real-world treatment patterns among patients with PAH, particularly before and after publication of the 2015 ESC/ERS guidelines.

METHODS

This was a retrospective study of adult commercial and Medicare Advantage with Part D (MAPD) enrollees with at least one claim for a PAH-related medication from January 01, 2012 to March 31, 2017, at least one medical claim with a pulmonary hypertension diagnosis, and continuous health plan enrollment at least 6 months prior to and at least 12 months following the date of the first pharmacy claim for PAH-related therapy (index date). Patients were divided into cohorts based on prescription of monotherapy or combination therapy and index date category (2012-2013, January 2014-July 2015, and August 2015-March 2017).

RESULTS

Out of 1878 patients, 90.8% initiated with monotherapy and 9.2% initiated with combination therapy. The percentage of patients with index combination therapy increased from 5.7% in 2012-2013 to 13.0% in August 2015-March 2017. Patients with index combination therapy had better persistence (11.6 months versus 10.3 months) and adherence (0.95 versus 0.85). Overall, the discontinuation rate was 40% and was higher in monotherapy versus combination therapy patients (42.8% versus 12.2%). Approximately 30.2% of patients had a second regimen, of which 50% were combination regimens. The time to combination therapy initiation decreased from 10.5 months in 2012-2013 to 3.4 months in August 2015-March 2017.

CONCLUSIONS

The majority of patients initiated monotherapy treatment for PAH, most often a phosphodiesterase 5 inhibitor (PDE5i). Patients with upfront combination therapy increased following publication of the 2015 ESC/ERS guidelines, indicating that physicians responded to the guideline's option of prescribing upfront combination therapy.

Medication adherence, hospitalization, and healthcare resource utilization and costs in patients with pulmonary arterial hypertension treated with endothelin receptor antagonists or phosphodiesterase type-5 inhibitors

Adherence to therapy for pulmonary arterial hypertension is essential to optimize patient outcomes, but data on real-world adherence to different pulmonary arterial hypertension drug classes are limited. This retrospective database analysis evaluated relationships between adherence, hospitalization, and healthcare costs in pulmonary arterial hypertension patients treated with endothelin receptor antagonists or phosphodiesterase type-5 inhibitors. From the IQVIA Adjudicated Health Plan Database, patients with pulmonary arterial hypertension were identified based on diagnostic codes and prescriptions for endothelin receptor antagonists (ambrisentan, bosentan, macitentan) or phosphodiesterase type-5 inhibitors (sildenafil, tadalafil) approved for pulmonary arterial hypertension. Patients were assigned to the class of their most recently initiated (index) pulmonary arterial hypertension therapy between 1 January 2009 and 30 June 2015. Medication adherence was measured by proportion of days covered; patients with proportion of days covered ≥80% were considered adherent. The proportion of adherent patients was higher for endothelin receptor antagonists (571/755; 75.6%) than for phosphodiesterase type-5 inhibitors (970/1578; 61.5%; P < 0.0001). In both groups, hospitalizations declined as proportion of days covered increased. Among adherent patients, those on endothelin receptor antagonists had a significantly lower hospitalization rate than those on phosphodiesterase type-5 inhibitors (23.1% versus 28.5%, P = 0. 0218), fewer hospitalizations (mean (standard deviation) 0.4 (0.8) versus 0.5 (0.9); P = 0.02), and mean hospitalization costs during the six-month post-index ($9510 versus $15,726, P = 0.0318). Increasing adherence reduced hospitalization risk more for endothelin receptor antagonists than for phosphodiesterase type-5 inhibitors (hazard ratio 0.176 versus 0.549, P = 0.001). Rates and numbers of rehospitalizations within 30 days post-discharge were similar between groups. Mean total costs were higher with endothelin receptor antagonists than phosphodiesterase type-5 inhibitors in all patients ($91,328 versus $72,401, P = 0.0003) and in adherent patients ($88,867 versus $56,300, P < 0.0001), driven by higher drug costs.

Impact of thyroiditis on 131I uptake during ablative therapy for differentiated thyroid cancer

CONTEXT

Differentiated thyroid cancer (DTC) is usually treated by thyroidectomy followed by radioiodine ablation and generally has a good prognosis. It may now be possible to limit the amount of treatment without impacting on efficacy. It is not known whether coexistent thyroiditis impacts on radioiodine uptake or on its potential efficacy, but this could provide a rationale for modification to current therapeutic protocols.

DESIGN

This was a retrospective cohort study of radioiodine uptake on imaging after radioiodine ablation for DTC in patients with and without concurrent thyroiditis. All patients with histologically confirmed DTC treated with radioiodine ablation after thyroidectomy in a single centre from 2012 to 2015 were included. The primary outcome assessed was the presence of low or no iodine uptake on post-ablation scan, as reported by a nuclear medicine physician blinded to the presence or absence of thyroiditis.

RESULTS

One hundred thirty patients with available histopathology results were included. Thyroiditis was identified in 42 post-operative specimens and 15 of these patients had low or no iodine uptake on post-ablation scan, compared to only 2 of 88 patients without thyroiditis (P < 0.0001) with further data analysis dividing the groups by ablation activity received (1100 MBq or 3000 MBq).

CONCLUSIONS

Concurrent thyroiditis may impair the uptake of radioactive iodine in management of DTC. Given that patients with DTC and thyroiditis already have a good prognosis, adopting a more selective approach to this step in therapy may be indicated. Large, longitudinal studies would be required to determine if omitting radioactive iodine therapy from those patients with concurrent thyroiditis has a measurable impact on mortality from thyroid cancer.

Echocardiography and monitoring patients receiving dopamine agonist therapy for hyperprolactinaemia: A joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology

This is a joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology on the role of echocardiography in monitoring patients receiving dopamine agonist (DA) therapy for hyperprolactinaemia. Evidence that DA pharmacotherapy causes abnormal valve morphology and dysfunction at doses used in the management of hyperprolactinaemia is extremely limited. Evidence of clinically significant valve pathology is absent, except for isolated case reports around which questions remain. Attributing change in degree of valvar regurgitation, especially in mild and moderate tricuspid regurgitation, to adverse effects of DA in hyperprolactinaemia should be avoided if there are no associated pathological changes in leaflet thickness, restriction or retraction. Note must be taken that even where morphological change in leaflet structure and function may be suspected, grading is semi-quantitative on echocardiography and may vary between different machines, ultrasound settings and operators. Decisions regarding discontinuation of medication should only be made after review of serial imaging by an echocardiographer experienced in analysing drug-induced valvulopathy or carcinoid heart disease. A standard transthoracic echocardiogram should be performed before a patient starts DA therapy for hyperprolactinaemia. Repeat transthoracic echocardiography should then be performed at 5 years after starting cabergoline in patients taking a total weekly dose less than or equal to 2 mg. If there has been no change on the 5-year scan, repeat echocardiography could continue at 5-yearly intervals. If a patient is taking more than a total weekly dose of 2 mg, then annual echocardiography is recommended.

Baseline history of patients using selexipag for pulmonary arterial hypertension

Introduction:

Since its introduction to the market in 2016, selexipag has been an alternative oral therapy among both treatment-naïve patients and those with mono or dual therapy failure; however, limited information is available regarding the presentation and management of patients with pulmonary arterial hypertension (PAH) prior to selexipag initiation. This study examined treatment patterns, healthcare utilization, and costs in the 12 months prior to and the 6 months following selexipag initiation.

Methods:

This was a retrospective study of adult commercial and Medicare Advantage with Part D (MAPD) health plan members with a medical or pharmacy claim for selexipag from 1 January 2016 through 31 May 2017, a diagnosis of pulmonary hypertension, and continuous health plan enrollment for 12 months prior to selexipag initiation (baseline period). Treatment patterns, healthcare utilization, and costs were measured over the baseline period and the 6 months following selexipag initiation (among patients with ⩾6 months of follow up).

Results:

After inclusion and exclusion criteria were applied, 95 patients were included in the analysis. At study start, 57.9% of patients were prescribed combination therapy, increasing to 69.5% immediately prior to selexipag initiation. Approximately 60% of patients had one baseline regimen. Emergency visits and inpatient admissions during the baseline period occurred in 63.2% and 48.4% of patients, respectively. Baseline medical costs rose steadily, increasing 266.8% in commercial and 26.7% in MAPD enrollees from the beginning to the end of the 12-month baseline period. PAH-related healthcare costs accounted for more than 80% of total costs. Mean medical costs in the 6 months following selexipag initiation were US$17,215 in commercial and US$23,976 in MAPD enrollees.

Conclusions:

The majority of patients with PAH remained on the same therapy in the 12 months prior to selexipag initiation despite high rates of healthcare utilization and increasing costs. Mean medical costs appeared to decrease after adding or switching to selexipag.

Echocardiography and monitoring patients receiving dopamine agonist therapy for hyperprolactinaemia: a joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology

This is a joint position statement of the British Society of Echocardiography, the British Heart Valve Society and the Society for Endocrinology on the role of echocardiography in monitoring patients receiving dopamine agonist (DA) therapy for hyperprolactinaemia. (1) Evidence that DA pharmacotherapy causes abnormal valve morphology and dysfunction at doses used in the management of hyperprolactinaemia is extremely limited. Evidence of clinically significant valve pathology is absent, except for isolated case reports around which questions remain. (2) Attributing change in degree of valvular regurgitation, especially in mild and moderate tricuspid regurgitation, to adverse effects of DA in hyperprolactinaemia should be avoided if there are no associated pathological changes in leaflet thickness, restriction or retraction. It must be noted that even where morphological change in leaflet structure and function may be suspected, grading is semi-quantitative on echocardiography and may vary between different machines, ultrasound settings and operators. (3) Decisions regarding discontinuation of medication should only be made after review of serial imaging by an echocardiographer experienced in analysing drug-induced valvulopathy or carcinoid heart disease. (4) A standard transthoracic echocardiogram should be performed before a patient starts DA therapy for hyperprolactinaemia. Repeat transthoracic echocardiography should then be performed at 5 years after starting cabergoline in patients taking a total weekly dose less than or equal to 2 mg. If there has been no change on the 5-year scan, repeat echocardiography could continue at 5-yearly intervals. If a patient is taking more than a total weekly dose of 2 mg, then annual echocardiography is recommended.

Treatment patterns, healthcare resource utilization, and healthcare costs among patients with pulmonary arterial hypertension in a real-world US database

Several new medications for pulmonary arterial hypertension (PAH) have recently been introduced; however, current real-world data regarding US patients with PAH are limited. We conducted a retrospective administrative claims study to examine PAH treatment patterns and summarize healthcare utilization and costs among patients with newly diagnosed PAH treated in US clinical practice. Patients newly treated for PAH from 1 January 2010 to 31 March 2015 were followed for ≥12 months. Patient characteristics, treatment patterns, healthcare resource utilization, and costs were described. Adherence (proportion of days covered), persistence (months until therapy discontinuation/modification), and the probability of continuing the index regimen were analyzed by index regimen cohort (monotherapy versus combination therapy). Of 1637 eligible patients, 93.8% initiated treatment with monotherapy and 6.2% with combination therapy. The most common index regimen was phosphodiesterase type 5 inhibitor (PDE-5I) monotherapy (70.0% of patients). A total of 581 patients (35.5%) modified their index regimen during the study. Most patients (55.4%) who began combination therapy did so on or within six months of the index date. Endothelin receptor agonists (ERAs) and combination therapies were associated with higher adherence than PDE-5Is and monotherapies, respectively. Healthcare utilization was substantial across the study population, with costs in the combination therapy cohort more than doubling from baseline to follow-up. The majority of patients were treated with monotherapies (most often, PDE-5Is), despite combination therapies and ERAs being associated with higher medication adherence. Index regimen adjustments occurred early and in a substantial proportion of patients, suggesting that inadequate clinical response to monotherapies may not be uncommon.

A randomised, open-label, parallel group phase 2 study of antisense oligonucleotide therapy in acromegaly

OBJECTIVE

ATL1103 is a second-generation antisense oligomer targeting the human growth hormone (GH) receptor. This phase 2 randomised, open-label, parallel-group study assessed the potential of ATL1103 as a treatment for acromegaly.

DESIGN

Twenty-six patients with active acromegaly (IGF-I >130% upper limit of normal) were randomised to subcutaneous ATL1103 200 mg either once or twice weekly for 13 weeks and monitored for a further 8-week washout period.

METHODS

The primary efficacy measures were change in IGF-I at week 14, compared to baseline and between cohorts. For secondary endpoints (IGFBP3, acid labile subunit (ALS), GH, growth hormone-binding protein (GHBP)), comparison was between baseline and week 14. Safety was assessed by reported adverse events.

RESULTS AND CONCLUSIONS

Baseline median IGF-I was 447 and 649 ng/mL in the once- and twice-weekly groups respectively. Compared to baseline, at week 14, twice-weekly ATL1103 resulted in a median fall in IGF-I of 27.8% (P = 0.0002). Between cohort comparison at week 14 demonstrated the median fall in IGF-I to be 25.8% (P = 0.0012) greater with twice-weekly dosing. In the twice-weekly cohort, IGF-I was still declining at week 14, and remained lower at week 21 than at baseline by a median of 18.7% (P = 0.0005). Compared to baseline, by week 14, IGFBP3 and ALS had declined by a median of 8.9% (P = 0.027) and 16.7% (P = 0.017) with twice-weekly ATL1103; GH had increased by a median of 46% at week 14 (P = 0.001). IGFBP3, ALS and GH did not change with weekly ATL1103. GHBP fell by a median of 23.6% and 48.8% in the once- and twice-weekly cohorts (P = 0.027 and P = 0.005) respectively. ATL1103 was well tolerated, although 84.6% of patients experienced mild-to-moderate injection-site reactions. This study provides proof of concept that ATL1103 is able to significantly lower IGF-I in patients with acromegaly.

Using Real World Evidence to Describe Pulmonary Arterial Hypertension Treatment Patterns, Healthcare Resource Utilization, and Costs Associated with PDE-5 Inhibitor Monotherapy

Background: Pulmonary arterial hypertension (PAH) is described by proliferation of small pulmonary arteries leading to increased pulmonary vascular resistance, right ventricular failure, and death. Research confirms long-term improvement in composite morbidity and mortality endpoints on some endothelin receptor antagonists alone and in combination with phosphodiesterase type 5 inhibitors (PDE-5is) but not with PDE-5i monotherapy. While current treatment guidelines incorporate these findings, a substantial number of patients are started or maintained on PDE-5i monotherapy. Objectives: This study describes real-world clinical practice and treatment patterns with PDE-5i monotherapy including events indicative of clinical worsening, treatment modifications, adherence, allcause healthcare resource utilization, and costs. Methods: This retrospective study analyzed PharMetrics Plus claims data including 150 million lives; study period was January 1, 2009 through December 31, 2013. Eligible patients were ≥18 years with ≥1 inpatient or ≥2 outpatient claims ≥30 days apart, a diagnosis of pulmonary hypertension or other chronic pulmonary heart disease, and an initial PDE-5i prescription. To include only World Health Organization group 1 PAH patients, ≥1 encounter for right-heart catheterization or Doppler echocardiogram was required during the pre-index period. Results: PDE-5i monotherapy for PAH treatment was associated with high treatment modification rates, low adherence, increased healthcare resource utilization, and high costs. At 12 months post index, 41.5% of patients experienced treatment modification. For the index therapy, 47% of patients had ≥80% adherence to therapy. Almost 50% of patients had ≥1 hospitalization, with costs increased three fold to $197 111 compared to $59 164 for non-hospitalized patients. Conclusions: Initial treatment with PDE-5i monotherapy was associated with substantial direct medical costs, including hospitalizations and emergency department visits, low therapy adherence and a high rate of treatment modifications.

Prostacyclin Use Among Patients with Pulmonary Arterial Hypertension in the United States: A Retrospective Analysis of a Large Health Care Claims Database

BACKGROUND

Prostacyclins play an important role in the management of pulmonary arterial hypertension (PAH). Intravenous prostacyclin was the first disease-specific treatment for patients with PAH. Subcutaneous and nonparenteral (oral or inhaled) formulations have subsequently become available. However, data are lacking on how these different prostacyclin formulations are being used in clinical practice.

OBJECTIVES

To (a) conduct retrospective analyses of a large U.S. health care claims database to describe the characteristics of patients with PAH initiating prostacyclin therapy, and (b) evaluate their treatment patterns, health care resource use, and associated costs.

METHODS

Truven Commercial and Medicare databases were used to define annual cohorts of adults with PAH between January 1, 2010, and October 31, 2015. These patients were identified based on claims with ICD-9-CM diagnoses indicative of PAH (codes 416.0 or 416.8) and claims for PAH-specific medications and PAH-related procedures. Patients with evidence of receiving a prostacyclin were identified, and prostacyclin use was categorized as parenteral versus nonparenteral. Health care costs were assessed alternatively employing an all-cause and PAH-related perspective.

RESULTS

Of 13,633 adults with identified PAH, 3,006 (22.0%) received a prostacyclin during at least 1 year of the study period, and annual prevalence of prostacyclin use ranged from 19.9% to 22.6%. Across calendar years, the median age of prostacyclin users ranged from 56 to 58 years, and 71.9%-75.8% were female. Among prostacyclin users, parenteral prostacyclin use declined from 63.2% in 2010 to 46.5% in 2015, while use of nonparenteral prostacyclins increased from 39.7% to 56.2% over the same period (both P < 0.001). Few patients (2.7%-4.1%) received both parenteral and nonparenteral formulations in a given calendar year. Among patients using prostacyclins, receipt of other PAH-specific medications increased from 62.1% in 2010 to 79.2% in 2015. Comparing the 6 months preceding the first prostacyclin prescription (any formulation) to the 6 months subsequent, mean overall health care costs rose from $61,243 to $119,283, and PAH-related health care costs increased from $58,815 to $116,661, driven mainly by PAH-specific medications, spending on which increased from $15,053 to $73,705 (all P < 0.001).

CONCLUSIONS

While overall use of prostacyclins was relatively constant from 2010 to 2015, our findings revealed a shift from parenteral to nonparenteral formulations, coupled with increased prescribing of PAH-related medications from other drug classes. Further research is needed to better understand how these changes in patterns of prostacyclin use affect levels of health care resource utilization and costs and patients' overall quality of life.

DISCLOSURES

This research was funded by Actelion Pharmaceuticals US, a Janssen pharmaceutical company of Johnson & Johnson. Burger has received grant funding from Actelion, Gilead Sciences, and United Therapeutics; personal fees from Actelion and Gilead Sciences; and nonfinancial support from Actelion. Pruett, Lickert, and Drake are employees of Actelion. Pruett and Lickert own shares in Actelion. Berger and Murphy are employees of Evidera, a consultancy that received payment from Actelion to conduct this research. Pruett, Lickert, Berger, and Drake contributed to study conception and participated with Burger in study design. Lickert and Murphy performed the data analyses. Burger, Pruett, Lickert, Murphy, and Drake interpreted the data. All authors participated in manuscript drafting and/or critical revision, approved the final manuscript, and agree to be accountable for all aspects of the work.

Healthcare resource utilization and costs for patients with pulmonary arterial hypertension: real-world documentation of functional class

BACKGROUND AND AIMS

Pulmonary arterial hypertension (PAH) is a rare medical disease in which patients experience increased pulmonary vascular resistance (PVR) and pulmonary arterial pressure that can result in remodeling of the pulmonary vasculature and heart, and eventually lead to right heart failure and death. As PAH progresses, patients become unable to perform even routine daily tasks without severe shortness of breath (dyspnea), fatigue, dizziness, and fainting (syncope). Treatment strategies largely depend on assessment of an individual patient's WHO Functional Class. The aim of the present study was to determine whether PAH functional decline, as described by the WHO Functional class (FC), is associated with increased healthcare costs for patients.

METHODS

Patients with a prescription for a FDA-approved treatment for PAH and a medical claim indicating chronic pulmonary heart disease or right heart catheterization were identified from an administrative claims database. Provider-reported data from prior authorization forms required for advanced PAH therapies and medical charts were examined for reported FC. Healthcare resource utilization and costs were the primary outcomes of interest. Costs were accounted in 2014 US dollars ($) from a healthcare payer perspective.

RESULTS

Patients with a reported FC-IV were observed to have the worst outcomes; averaging significantly more inpatient admissions, longer average lengths of stay, and more emergency department visits than the other FC sub-groups, resulting in higher medical costs.

CONCLUSIONS

Using administrative data to document disease severity, this study replicates and expands on findings obtained from the registry study; disease severity was associated with higher healthcare resource utilization and costs. Stakeholders' implications for patient management are discussed.

Effectiveness of Metyrapone in Treating Cushing's Syndrome: A Retrospective Multicenter Study in 195 Patients

BACKGROUND

Cushing's syndrome (CS) is a severe condition with excess mortality and significant morbidity necessitating control of hypercortisolemia. There are few data documenting use of the steroidogenesis inhibitor metyrapone for this purpose.

OBJECTIVE

The objective was to assess the effectiveness of metyrapone in controlling cortisol excess in a contemporary series of patients with CS.

DESIGN

This was designed as a retrospective, multicenter study.

SETTING

Thirteen University hospitals were studied.

PATIENTS

We studied a total of 195 patients with proven CS: 115 Cushing's disease, 37 ectopic ACTH syndrome, 43 ACTH-independent disease (adrenocortical carcinoma 10, adrenal adenoma 30, and ACTH-independent adrenal hyperplasia 3).

MEASUREMENTS

Measurements included biochemical parameters of activity of CS: mean serum cortisol "day-curve" (CDC) (target 150-300 nmol/L); 9 am serum cortisol; 24-hour urinary free cortisol (UFC).

RESULTS

A total of 164/195 received metyrapone monotherapy. Mean age was 49.6 ± 15.7 years; mean duration of therapy 8 months (median 3 mo, range 3 d to 11.6 y). There were significant improvements on metyrapone, first evaluation to last review: CDC (91 patients, 722.9 nmol/L [26.2 μg/dL] vs 348.6 nmol/L [12.6 μg/dL]; P < .0001); 9 am cortisol (123 patients, 882.9 nmol/L [32.0 μg/dL] vs 491.1 nmol/L [17.8 μg/dL]; P < .0001); and UFC (37 patients, 1483 nmol/24 h [537 μg/24 h] vs 452.6 nmol/24 h [164 μg/24 h]; P = .003). Overall, control at last review: 55%, 43%, 46%, and 76% of patients who had CDCs, UFCs, 9 am cortisol less than 331 nmol/L (12.0 μg/dL), and 9 am cortisol less than upper limit of normal/600 nmol/L (21.7 μg/dL). Median final dose: Cushing's disease 1375 mg; ectopic ACTH syndrome 1500 mg; benign adrenal disease 750 mg; and adrenocortical carcinoma 1250 mg. Adverse events occurred in 25% of patients, mostly mild gastrointestinal upset and dizziness, usually within 2 weeks of initiation or dose increase, all reversible.

CONCLUSIONS

Metyrapone is effective therapy for short- and long-term control of hypercortisolemia in CS.

Economic grand rounds: experience with mandated use of generic medications for patients covered by the mental health safety net

Reducing pharmacy costs without increasing adverse outcomes would relieve some pressure on mental health budgets. This column describes the experience of a publicly funded provider network in a Michigan county that mandated generic use of psychotropic medications to address financial challenges. The percentage of brand-name medications and cost per prescription declined with the policy change, resulting in lower total pharmacy expenditures. No increase was noted in prescriptions per patient or psychiatric hospitalizations. Changes were sustained after the initial implementation period. Mandating generic use may be feasible as a tool for constraining pharmacy costs in mental health budgets.

Childhood obesity increases left-ventricular mass irrespective of blood pressure status

Adults with a left-ventricular mass index (LVMI) in grams normalized to height in meters(2.7) (LVMI g/m(2.7)) >51 g/m(2.7) are more prone to cardiovascular and cerebrovascular events. We delineated the odds for cardiac structural sequelae amongst apparently normal white and African-American (AA) children with varying body mass indices (BMI) and office blood pressures. A total of 2,071 children with normal echocardiograms were categorized into risk groups based on BMI and systolic blood pressures (SBPs). Predictors of cardiac sequelae examined were age, sex, race, and z-scores (z) for BMI, SBP, and diastolic blood pressure. Cardiac sequelae measures included (LVMI g/m(2.7)) >51 g/m(2.7), (LVMI) (g/m(2.7)) z, left atrial size (LA(ht)) (mm) z, and relative wall thickness z. Mean age was 14 ± 2 years with 56 % being male and 13 % being AA. Children were divided into "controls" (n = 1,059) and risk groups based on BMI and SBP. Odds ratio for LVMI (g/m(2.7)) > 51.0 g/m(2.7), varied from 5.3 up to 8.5 in children with increased BMI. Both increased BMI and SBP z were associated with increased LVMI (g/m(2.7)) z; however, BMI z had a stronger association. Increased BMI z and AA race were associated with greater LA(ht) (mm) z. AA controls had a nonsignificantly increased LVMI z and a significantly increased LA(ht) (mm) and RWT z. Being overweight or obese is associated with cardiac sequelae in children to the extent known to be associated with adverse outcomes in adults. Healthy AA children have unique cardiac structural differences.

Re-occurrence of pancreatic insulinoma: an usual cause of hypoglycaemia

A 42-year-old woman presented to her general practitioner (GP) with episodes of feeling 'shaky' exacerbated by physical exercise and prolonged fast. She was previously diagnosed with an insulinoma in 2006 (serum glucose 1.6 mmol/l, serum insulin 3.1 mIU/l and serum C peptide <165 pmol/l). CT abdomen/transabdominal ultrasound revealed a 1 cm insulinoma in the uncinate process of the pancreas and the patient later underwent pancreatic enucleation in 2006. Postpancreatic enucleation, 72 h fast was negative. The patient remained asymptomatic postoperation and re-presented to a locum GP 6 years later with initial symptoms. She was reviewed during her annual follow-up and, owing to concerns relating to her background, she was admitted to the specialist endocrine department for further investigations. A 72 h fast was positive for hypoglycaemia with serum glucose level 1.8 mmol/l, serum insulin 8.6 mIU/l and serum C peptide 443 pmol/l.

GH replacement causing acute hyperglycaemia and ketonuria in a type 1 diabetic patient

A state of insulin resistance is common to the clinical conditions of both chronic growth hormone (GH) deficiency and GH excess (acromegaly). GH has a physiological role in glucose metabolism in the acute settings of fast and exercise and is the only anabolic hormone secreted in the fasting state. We report the case of a patient in whom knowledge of this aspect of GH physiology was vital to her care. A woman with well-controlled type 1 diabetes mellitus who developed hypopituitarism following the birth of her first child required GH replacement therapy. Hours after the first dose, she developed a rapid metabolic deterioration and awoke with hyperglycaemia and ketonuria. She adjusted her insulin dose accordingly, but the pattern was repeated with each subsequent increase in her dose. Acute GH-induced lipolysis results in an abundance of free fatty acids (FFA); these directly inhibit glucose uptake into muscle, and this can lead to hyperglycaemia. This glucose–fatty acid cycle was first described by Randle et al. in 1963; it is a nutrient-mediated fine control that allows oxidative muscle to switch between glucose and fatty acids as fuel, depending on their availability. We describe the mechanism in detail.

Prenatal ductal thrombosis presenting as cyanotic heart lesion

We present a case of a late-preterm infant admitted for suspected cyanotic heart disease who was found to have a thrombosed ductus arteriosus. Maternal history was significant for heterozygosity for Factor V Leiden, treated with enoxaparin during her pregnancy, and congenital hearing loss. The neonate did not have a Factor V Leiden mutation detected, but was found to have a heterozygous mutation within the MFTHR gene. He was treated with anticoagulation, with improving hemodynamics measured by echocardiogram. This case presents a rare disease, which is potentially fatal if diagnosis is delayed.

Multiple Mycobacterium antigens induce interferon-gamma production from sarcoidosis peripheral blood mononuclear cells

Studies of sarcoidosis immunology have noted oligoclonal T cell populations, suggesting cell-mediated immunity that is antigen-specific. Sarcoidosis immunology and pathology are most similar to mycobacterial infections. Mycobacterium tuberculosis infection in mice and humans reflects T helper 1 (Th1) immune responses to multiple cell wall and secreted antigens. We investigated if the oligoclonal immune response in individual sarcoidosis subjects could be elicited by multiple secreted mycobacterial antigens by performing ex vivo enzyme-linked immunospot assay (ELISPOT) on peripheral blood mononuclear cells (PBMC) from 30 sarcoidosis, 26 purified protein derivative negative (PPD-) control and 10 latent tuberculosis subjects (PPD+) to assess Th1 responses to mycobacterial superoxide dismutase A (sodA), catalase-peroxidase (katG) and early secreted antigenic target protein (ESAT-6). A significant difference was noted among the sarcoidosis and PPD- control subjects to ESAT-6 [12 of 30 versus one of 26 (P = 0.0014)], katG [nine of 30 versus none of 26 (P = 0.002)] and sodA [12 of 30 versus none of 26 (P = 0.002)]. There was no significant difference between sarcoidosis and PPD+ subjects. Twelve sarcoidosis subjects recognized two or more mycobacterial proteins, as well as multiple distinct epitopes within individual proteins. One sarcoidosis subject on whom we collected bronchoalveolar lavage (BAL) fluid and PBMC had no recognition of mycobacterial antigens using PBMC, but BAL fluid demonstrated strong Th1 immune responses to ESAT-6 and katG. Individual sarcoidosis subjects recognized not only multiple mycobacterial proteins, but multiple distinct peptides within a specific protein, thus demonstrating that multiple mycobacterial epitopes elicit the Th1 immune response observed. Immune responses by sarcoidosis T cells to mycobacterial proteins may have an important role in sarcoidosis pathogenesis.