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Clarke, B.L.

https://orcid.org/0000-0002-3801-9546

Mayo Clinic

Mayo Clinic

Citations 74

Long‐term outcomes in patients with multiple endocrine neoplasia type 1 and pancreaticoduodenal neuroendocrine tumours
Donegan, Diane , Ospina, Naykky Singh , Rodríguez‐Gutiérrez, René , Al‐Hilli, Zahraa , Thompson, Geoffrey B. , Clarke, B.L. , Young, William F. , Singh Ospina, Naykky

Clinical Endocrinology | October 22, 2016 | Volume: 86 | Issue: 2 | Pages: 199-206

10.1111/cen.13264 Get It

SummaryBackgroundIn patients with multiple endocrine neoplasia type 1 (MEN‐1), pancreaticoduodenal (PD) neuroendocrine tumours (NETs) are associated with early mortality, yet the best treatment strategy remains uncertain.AimTo assess patient important outcomes (mortality and metastasis) of PD‐NETs and predictors of outcomes in patients with MEN‐1.MethodsRetrospective cohort of patients with MEN‐1 who attended the Mayo Clinic, Rochester, MN from 1997 to 2014.ResultsWe identified 287 patients with MEN‐1; 199 (69%) patients had 217 PD‐NETs. Among those with a PD‐NETs, 129 (65%) had surgery of which 90 (70%) had their primary surgery performed at Mayo Clinic. The median postoperative follow‐up was 8 years during which 13 (14%) patients died. The mean (±standard deviation) age of death was 51 (±9) years. Tumour size, metastasis at surgery or tumour type were not predictive of mortality, but for every year older at surgery, the odds of metastasis increased by 6%. Surgery was not performed in 70 (35%) patients. Among those who were observed/medically managed without known metastatic disease, mean tumour growth was 0·02 cm/year (range, −0·13–0·4 cm/year). Four patients (7%) died at a median age of 77 (range, 51–89) years.ConclusionPD‐NETs are common in patients with MEN‐1 and are associated with early mortality even after surgical intervention. Active surveillance is a viable option in nonaggressive PD‐NETs, although definitive factors identifying such patients are lacking. Therefore, counselling regarding risks and benefits of current treatment options remains integral to the care of patients with MEN‐1.
Management of Hypoparathyroidism: Summary Statement and Guidelines
Brandi, Maria Luisa , Bilezikian, John P. , Shoback, Dolores , Bouillon, Roger , Thakker, Rajesh V. , Khan, Aliya , Potts, John T. , Clarke, Bart L, Khan, Aliya A, Clarke, B.L. , Brandi, Maria Luisa , Thakker, Rajesh V

The Journal of Clinical Endocrinology & Metabolism | March 4, 2016 | Volume: 101 | Issue: 6 | Pages: 2273-2283

10.1210/jc.2015-3907 Get It

Abstract Objective: Hypoparathyroidism is a rare disorder characterized by hypocalcemia and absent or deficient PTH. This report presents a summary of current information about epidemiology, presentation, diagnosis, clinical features, and management and proposes guidelines to help clinicians diagnose, evaluate, and manage this disorder. Participants: Participants in the First International Conference on the Management of Hypoparathyroidism represented a worldwide constituency with acknowledged interest and expertise in key basic, translational, and clinical aspects of hypoparathyroidism. Three Workshop Panels were constituted to address questions for presentation and discussion at the Conference held in Florence, Italy, May 7–9, 2015. At that time, a series of presentations were made, followed by in-depth discussions in an open forum. Each Workshop Panel also met in closed sessions to formulate the three evidence-based reports that accompany this summary statement. An Expert Panel then considered this information, developed summaries, guidelines, and a research agenda that constitutes this summary statement. Evidence: Preceding the conference, each Workshop Panel conducted an extensive literature search as noted in the individual manuscripts accompanying this report. All presentations were based upon the best peer-reviewed information taking into account the historical and current literature. Consensus Process: This report represents the Expert Panel's synthesis of the conference material placed in a context designed to be relevant to clinicians and those engaged in cutting-edge studies of hypoparathyroidism. Conclusions: This document not only provides a summary of our current knowledge but also places recent advances in its management into a context that should enhance future advances in our understanding of hypoparathyroidism.
Managing Osteoporosis in Patients on Long-Term Bisphosphonate Treatment: Report of a Task Force of the American Society for Bone and Mineral Research
Adler, Robert A. , Fuleihan, Ghada El‐Hajj , Bauer, Douglas C. , Camacho, Pauline M., Clines, Gregory A. , Edwards, Beatrice J. , Favus, Murray J., Greenspan, Susan L., McKinney, Ross E. , Pignolo, Robert J. , Sellmeyer, Deborah E. , Clarke, Bart L, Drake, Matthew T. , Clarke, B.L. , Compston, Juliet , Bauer, Douglas C , El-Hajj Fuleihan, Ghada

Journal of Bone and Mineral Research | September 9, 2015 | Volume: 31 | Issue: 1 | Pages: 16-35

10.1002/jbmr.2708 Get It

ABSTRACT Bisphosphonates (BPs) are the most commonly used medications for osteoporosis. This ASBMR report provides guidance on BP therapy duration with a risk-benefit perspective. Two trials provided evidence for long-term BP use. In the Fracture Intervention Trial Long-term Extension (FLEX), postmenopausal women receiving alendronate for 10 years had fewer clinical vertebral fractures than those switched to placebo after 5 years. In the HORIZON extension, women who received 6 annual infusions of zoledronic acid had fewer morphometric vertebral fractures compared with those switched to placebo after 3 years. Low hip T-score, between –2 and –2.5 in FLEX and below –2.5 in HORIZON extension, predicted a beneficial response to continued therapy. Hence, the Task Force suggests that after 5 years of oral BP or 3 years of intravenous BP, reassessment of risk should be considered. In women at high risk, for example, older women, those with a low hip T-score or high fracture risk score, those with previous major osteoporotic fracture, or who fracture on therapy, continuation of treatment for up to 10 years (oral) or 6 years (intravenous), with periodic evaluation, should be considered. The risk of atypical femoral fracture, but not osteonecrosis of the jaw, clearly increases with BP therapy duration, but such rare events are outweighed by vertebral fracture risk reduction in high-risk patients. For women not at high fracture risk after 3 to 5 years of BP treatment, a drug holiday of 2 to 3 years can be considered. The suggested approach for long-term BP use is based on limited evidence, only for vertebral fracture reduction, in mostly white postmenopausal women, and does not replace the need for clinical judgment. It may be applicable to men and patients with glucocorticoid-induced osteoporosis, with some adaptations. It is unlikely that future trials will provide data for formulating definitive recommendations. © 2015 American Society for Bone and Mineral Research.
Teriparatide Therapy and Reduced Postoperative Hospitalization for Postsurgical Hypoparathyroidism
Bancos, Irina , Thompson, Geoffrey B. , Richards, Melanie L., Kasperbauer, Jan L. , Stan, Marius N. , Clarke, Bart L, Drake, Matthew T. , Shah, Mithun V , Clarke, B.L. , Bancos, Irina , Stan, Marius N

JAMA Otolaryngology–Head & Neck Surgery | August 27, 2015 | Volume: 141 | Issue: 9 | Pages: 822

10.1001/jamaoto.2015.1497 Get It

Serum 25-Hydroxyvitamin D Levels: Variability, Knowledge Gaps, and the Concept of a Desirable Range
Fuleihan, Ghada El‐Hajj , Bouillon, Roger , Chakhtoura, Marlene , Cooper, Cyrus , Clarke, Bart, Clarke, B.L. , McClung, Michael R. , Singh, Ravinder J. , Cooper, Cyrus , El-Hajj Fuleihan, Ghada

Journal of Bone and Mineral Research | May 8, 2015 | Volume: 30 | Issue: 7 | Pages: 1119-1133

10.1002/jbmr.2536 Get It

ABSTRACT Hypovitaminosis D is prevalent worldwide but proportions vary widely between regions, depending on genetic and lifestyle factors, the threshold to define deficiency, and accuracy of 25-hydroxyvitamin D (25OHD) assays used. Latitude, pollution, concealing clothing, sun exposure, gender, dietary habits, and lack of government regulation account for up to 50% in variations in serum 25OHD levels, whereas genetic polymorphisms in the vitamin D pathway account for less than 5%. Organizations/societies have developed guidelines for recommended desirable 25OHD levels and vitamin D doses to reach them, but their applicability across age groups and populations are still debated. This article and the accompanying online Supporting Information highlight sources of variations in circulating 25OHD levels, uncertainties and knowledge gaps, and analytical problems facing 25OHD assays, while keeping efficacy and safety data as the dominant factors when defining a desirable range for 25OHD levels. We propose a desirable range of 20 to 40 ng/mL (50 to 100 nmol/L), provided precise and accurate assays are used. Although slightly lower levels, 15 to 20 ng/mL, may be sufficient for some infants and adults, higher levels, 40 to 60 ng/mL, may still be safe. This desirable range allows physicians to tailor treatment while taking season, lifestyle, vitamin D intake, and other sources of variation into account. We reserve 25OHD measurements for at-risk patients, defined by disease or lifestyle, and the use of 25OHD assays calibrated against the recommended international standards. Most target groups reach desirable target levels by a daily intake of 400 to 600 IU for children and 800 IU for adults. A total daily allowance of vitamin D of up to 1000 IU in the pediatric age groups, and up to 2000 IU in adults, tailored to an individual patient risk profile, is probably safe over long durations. Additional data are needed to validate the proposed range and vitamin D doses, especially in children, pregnant women, and non-white populations. © 2015 American Society for Bone and Mineral Research.
Prevalence of parathyroid carcinoma in 348 patients with multiple endocrine neoplasia type 1 – case report and review of the literature
Ospina, Naykky Singh , Sebo, Thomas J., Thompson, Geoffrey B. , Young, William F., Ospina, Naykky Singh , Singh Ospina, Naykky, Clarke, Bart L, Clarke, B.L. , Singh Ospina, Naykky M , Singh Ospina, Naykky

Clinical Endocrinology | December 31, 2014 | Volume: 84 | Issue: 2 | Pages: 244-249

10.1111/cen.12714 Get It

SummaryObjectiveTo report the prevalence of parathyroid carcinoma (PC) in patients with multiple endocrine neoplasia type 1 (MEN1) and review of the literature.BackgroundPrimary hyperparathyroidism (PHP) is the most common manifestation of MEN1. The occurrence of PC in patients with MEN1 is rare and the literature regarding the clinical manifestations – including the prevalence of the disease – is scarce.ContextSingle tertiary care centre experience from 1977 to 2013.DesignElectronic search of the medical records to identify a cohort of patients with MEN1. Literature review based on current case reports.PatientsSingle case of PC in a cohort of 348 patients with MEN1. Ten cases of PC in patients with MEN1 reported in the literature.MeasurementClinical features of PC in patients with MEN1.ResultsThe prevalence of PC in 348 patients with MEN1 was found to be 0·28% (95% CI, 0–1·4%). Based on the current published cases of PC in patients with MEN1, 54·5% were women, mean age at diagnosis was 48·3 years, and the serum PTH concentrations at least four times the upper limit of the reference range in 73% of the cases.ConclusionPC in patients with MEN 1 is rare with a prevalence of 0·28%, and the clinical features are similar to PC in patients without MEN1.
Bone disease in hypoparathyroidism
Clarke, B.L. , Clarke, Bart L

Arquivos Brasileiros de Endocrinologia & Metabologia | August 20, 2014 | Volume: 58 | Issue: 5 | Pages: 545-552

10.1590/0004-2730000003399 Get It

Hypoparathyroidism is a rare disorder that may be acquired or inherited. Postsurgical hypoparathyroidism is responsible for the majority of acquired hypoparathyroidism. Bone disease occurs in hypoparathyroidism due to markedly reduced bone remodeling due to the absence or low levels of parathyroid hormone. Chronically reduced bone turnover in patients with hypoparathyroidism typically leads to higher bone mass than in age- and sex-matched controls. Whether this increased bone density reduces fracture risk is less certain, because while increased bone mineralization may be associated with increased brittleness of bone, this does not appear to be the case in hypoparathyroidism. Treatment of hypoparathyroidism with recombinant parathyroid hormone may reduce bone mineral density but simultaneously strengthen the mechanical properties of bone.
Osteoporosis Prevention, Screening, and Treatment: A Review
Kling, Juliana M. , Sandhu, Nicole P. , Clarke, B.L. , Kling, Juliana M

Journal of Women's Health | April 25, 2014 | Volume: 23 | Issue: 7 | Pages: 563-572

10.1089/jwh.2013.4611 Get It

Osteoporosis, defined as low bone mass leading to increased fracture risk, is a major health problem that affects approximately 10 million Americans. The aging U.S. population is predicted to contribute to as much as a 50% increase in prevalence by 2025. Although common, osteoporosis can be clinically silent, and without prevention and screening, the costs of osteoporotic fracture–related morbidity and mortality will burden the U.S. healthcare system. This is a particularly relevant concern in the context of diminishing health care resources. Dual-energy X-ray absorptiometry is the most widely used, validated technique for measuring bone mineral density (BMD) and diagnosing osteoporosis. Cost-effectiveness analyses support early detection and treatment of high-risk patients with antiresorptive medications such as bisphosphonates. Moreover, optimization of bone health throughout life can help prevent osteoporosis. Current guidelines recommend screening women by age 65 years, but because no guidelines for screening intervals exist, decisions are made on the basis of clinical judgment alone. Although the recent literature provides some guidance, this review further explores current recommendations in light of newer evidence to provide more clarity on prevention, screening, and management strategies for patients with osteoporosis in the primary care setting.
Coexisting Primary Hyperparathyroidism and Sarcoidosis Cause Increased Angiotensin-Converting Enzyme and Decreased Parathyroid Hormone and Phosphate Levels
Lim, Vivien, Clarke, B.L.

The Journal of Clinical Endocrinology & Metabolism | March 15, 2013 | Volume: 98 | Issue: 5 | Pages: 1939-1945

10.1210/jc.2012-4197 Get It

FGF23 Regulation of Phosphorus Homeostasis Is Dependent on PTH
Clarke, B.L.

Endocrinology | October 20, 2011 | Volume: 152 | Issue: 11 | Pages: 4016-4018

10.1210/en.2011-1720 Get It