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Dive into the research topics where Linda C. Hemphill is active.

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Featured researches published by Linda C. Hemphill.


Circulation | 1994

Triglyceride- and cholesterol-rich lipoproteins have a differential effect on mild/moderate and severe lesion progression as assessed by quantitative coronary angiography in a controlled trial of lovastatin.

Howard N. Hodis; Wendy J. Mack; Stanley P. Azen; Petar Alaupovic; Janice M. Pogoda; Laurie LaBree; Linda C. Hemphill; Dieter M. Kramsch; David H. Blankenhorn

BACKGROUNDThe Monitored Atherosclerosis Regression Study, a randomized, double-blind, placebo-controlled, 2-year trial of lovastatin monotherapy, found that coronary lesions or = 50% S at baseline had different responses to therapy. We now report on clinical, lipid, and nonlipid risk factors of treatment response in these lesion subsets.METHODS AND RESULTSTwo hundred seventy subjects, 37 to 67 years old, with plasma total cholesterol (TC) 190 to 295 mg/dL (4.91 to 7.63 mmol/L) and total triglyceride or = 50% S) lesions in 220 angiogram pairs analyzed by computer quantitative coronary angiography. In the placebo group, risk factors (P < .05) for the progression of mild/moderate lesions were trig...


Circulation | 2011

Pilot Study of Extracorporeal Removal of Soluble Fms-Like Tyrosine Kinase 1 in Preeclampsia

Ravi Thadhani; Tuelay Kisner; Henning Hagmann; Verena Bossung; Stefanie Noack; W Schaarschmidt; Alexander Jank; Angela Kribs; Oliver A. Cornely; Claudia Kreyssig; Linda C. Hemphill; Alan C. Rigby; Santosh Khedkar; Tom H. Lindner; Peter Mallmann; Holger Stepan; S. Ananth Karumanchi; Thomas Benzing

Background— Targeted therapies to stabilize the clinical manifestations and prolong pregnancy in preeclampsia do not exist. Soluble fms-like tyrosine kinase 1 (sFlt-1), an alternatively spliced variant of the vascular endothelial growth factor receptor 1, induces a preeclampsia-like phenotype in experimental models and circulates at elevated levels in human preeclampsia. Removing sFlt-1 may benefit women with very preterm (<32 weeks) preeclampsia. Methods and Results— We first show that negatively charged dextran sulfate cellulose columns adsorb sFlt-1 in vitro. In 5 women with very preterm preeclampsia and elevated circulating sFlt-1 levels, we next demonstrate that a single dextran sulfate cellulose apheresis treatment reduces circulating sFlt-1 levels in a dose-dependent fashion. Finally, we performed multiple apheresis treatments in 3 additional women with very preterm (gestational age at admission 28, 30, and 27+4 weeks) preeclampsia and elevated circulating sFlt-1 levels. Dextran sulfate apheresis lowered circulating sFlt-1, reduced proteinuria, and stabilized blood pressure without apparent adverse events to mother and fetus. Pregnancy lasted for 15 and 19 days in women treated twice and 23 days in a woman treated 4 times. In each, there was evidence of fetal growth. Conclusions— This pilot study supports the hypothesis that extracorporeal apheresis can lower circulating sFlt-1 in very preterm preeclampsia. Further studies are warranted to determine whether this intervention safely and effectively prolongs pregnancy and improves maternal and fetal outcomes in this setting.


Journal of Acquired Immune Deficiency Syndromes | 2005

Increased cardiovascular disease risk indices in HIV-infected women.

Sara E. Dolan; Colleen Hadigan; Kathleen M. Killilea; Meghan P. Sullivan; Linda C. Hemphill; Robert S. Lees; David A. Schoenfeld; Steven Grinspoon

Little is known regarding cardiovascular disease risk indices in HIV-infected women. This study investigated cardiovascular disease risk indices in 100 consecutively recruited HIV-infected women and 75 healthy female control subjects. Subjects were recruited from hospital- and community-based health care providers. C-reactive protein (CRP), interleukin-6 (IL-6), adiponectin, lipid, and glucose levels were the main outcome measures. CT scan, dual-energy x-ray absorptiometry (DXA), and anthropometry were used to assess body composition. Although similar in age, weight, and racial composition, HIV-infected women demonstrated higher CRP (4.6 ± 0.7 vs. 2.3 ± 0.4 mg/L, P = 0.007), IL-6 (2.7 ± 0.2 vs. 1.8 ± 0.1 pg/mL, P = 0.02), triglyceride (1.84 ± 0.21 vs. 0.85 ± 0.05 mM, P = 0.0002), 2-hour glucose after oral glucose challenge (6.88 ± 0.22 vs. 5.72 ± 0.17 mM, P = 0.0003), and fasting insulin (81 ± 8 vs. 45 ± 2 pM, P = 0.0002) and lower high-density lipoprotein cholesterol (1.17 ± 0.03 vs. 1.45 ± 0.05 mM, P < 0.0001) and adiponectin (5.4 ± 0.3 vs. 7.6 ± 0.5 mg/L, P = 0.0001) levels compared with the control population. HIV-infected women had more abdominal visceral fat and less extremity fat by CT and DXA scan and demonstrated a higher waist-to-hip ratio (WHR) than the control population. Within the HIV group, CRP and other indices were significantly related to body composition in stepwise regression models. Among all subjects, WHR, but not HIV status, was significantly related to CRP and other cardiovascular disease risk indices. HIV-infected women demonstrate significantly increased risk factors for cardiovascular disease in association with abnormal fat distribution.


JAMA | 2008

Low-Dose Physiological Growth Hormone in Patients With HIV and Abdominal Fat Accumulation: A Randomized Controlled Trial

Janet Lo; Sung Min You; Bridget Canavan; James Liebau; Greg Beltrani; Polyxeni Koutkia; Linda C. Hemphill; Hang Lee; Steven Grinspoon

CONTEXT Antiretroviral therapy can be associated with visceral adiposity and metabolic complications, increasing cardiovascular risk, and reduced growth hormone (GH) secretion may be a contributing factor. OBJECTIVE To investigate the effects of low-dose physiological GH administration on body composition, glucose, and cardiovascular parameters in patients with human immunodeficiency virus (HIV) having abdominal fat accumulation and relative GH deficiency. DESIGN, SETTING, AND PATIENTS A randomized, double-blind, placebo-controlled trial of 56 patients with HIV, abdominal fat accumulation, and reduced GH secretion (peak GH <7.5 ng/mL) conducted at a US academic medical center between November 2003 and October 2007. INTERVENTION Patients were randomly assigned to receive either subcutaneous GH or matching placebo titrated to the upper quartile of normal insulinlike growth factor 1 (IGF-1) range for 18 months. Starting dose was 2 microg/kg/d and increased to maximum dose of 6 microg/kg/d (average dose, 0.33 mg/d). MAIN OUTCOME MEASURES Change in body composition assessed by computed tomographic scan and dual-energy x-ray absorptiometry. Secondary outcomes included glucose, IGF-1, blood pressure (BP), and lipids. Treatment effect was the difference in the change between GH and placebo groups, using all available data. RESULTS Fifty-five patients (26 with GH and 29 with placebo) were included in the safety analyses and 52 patients (25 with GH and 27 with placebo) were included in the efficacy analyses. Visceral adipose tissue area (treatment effect [last-value-carried-forward analysis {n = 56}, -19 cm(2); 95% confidence interval {CI}, -37 to -0.3 cm(2)], -19 cm(2); 95% CI, -38 to -0.5 cm(2); P = .049); trunk fat (-0.8 kg; 95% CI, -1.5 to -0.04 kg; P = .04); diastolic BP (-7 mm Hg; 95% CI, -11 to -2 mm Hg; P = .006); and triglycerides (-7 mg/dL, P = .002) improved but 2-hour glucose levels on glucose tolerance testing increased in the GH group vs the placebo group (treatment effect, 22 mg/dL; 95% CI, 6-37 mg/dL; P = .009). The IGF-1 levels increased (treatment effect, 129 ng/mL; 95% CI, 95-164 ng/mL; P < .001). Adverse events were not increased for GH vs placebo (23%; 95% CI, 9%-44% vs 28%; 95% CI, 13%-47%; P = .70). CONCLUSIONS In HIV-associated abdominal fat accumulation and relative GH deficiency, low-dose GH received for 18 months resulted in significantly reduced visceral fat and truncal obesity, triglycerides, and diastolic BP, but 2-hour glucose levels on glucose tolerance testing were increased. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00100698.


American Heart Journal | 2014

Rationale and design of the familial hypercholesterolemia foundation CAscade SCreening for Awareness and DEtection of Familial Hypercholesterolemia registry

Emily C. O’Brien; Matthew T. Roe; Elizabeth S. Fraulo; Eric D. Peterson; Christie M. Ballantyne; Jacques Genest; Samuel S. Gidding; E. Hammond; Linda C. Hemphill; Lisa C. Hudgins; Iris Kindt; Patrick M. Moriarty; Joyce L. Ross; James Underberg; Karol Watson; Dave Pickhardt; Daniel J. Rader; Katherine Wilemon; Joshua W. Knowles

BACKGROUND Familial hypercholesterolemia (FH) is a hereditary condition caused by various genetic mutations that lead to significantly elevated low-density lipoprotein cholesterol levels and resulting in a 20-fold increased lifetime risk for premature cardiovascular disease. Although its prevalence in the United States is 1 in 300 to 500 individuals, <10% of FH patients are formally diagnosed, and many are not appropriately treated. Contemporary data are needed to more fully characterize FH disease prevalence, treatment strategies, and patient experiences in the United States. DESIGN The Familial Hypercholesterolemia Foundation (a patient-led nonprofit organization) has established the CAscade SCreening for Awareness and DEtection of Familial Hypercholesterolemia (CASCADE FH) Registry as a national, multicenter initiative to identify US FH patients, track their treatment, and clinical and patient-reported outcomes over time. The CASCADE FH will use multiple enrollment strategies to maximize identification of FH patients. Electronic health record screening of health care systems will provide an efficient mechanism to identify undiagnosed patients. A group of specialized lipid clinics will enter baseline and annual follow-up data on demographics, laboratory values, treatment, and clinical events. Patients meeting prespecified low-density lipoprotein or total cholesterol criteria suspicious for FH will have the opportunity to self-enroll in an online patient portal with information collected directly from patients semiannually. Registry patients will be provided information on cascade screening and will complete an online pedigree to assist with notification of family members. SUMMARY The Familial Hypercholesterolemia Foundation CASCADE FH Registry represents a novel research paradigm to address gaps in knowledge and barriers to comprehensive FH screening, identification, and treatment.


The Journal of Clinical Endocrinology and Metabolism | 2010

Growth Hormone Deficiency after Treatment of Acromegaly: A Randomized, Placebo-Controlled Study of Growth Hormone Replacement

Karen K. Miller; Tamara Wexler; Pouneh K. Fazeli; Lindsay Gunnell; Gwenda J. Graham; Catherine Beauregard; Linda C. Hemphill; Lisa B. Nachtigall; Jay S. Loeffler; Brooke Swearingen; Beverly M. K. Biller; Anne Klibanski

CONTEXT The effects of GH replacement therapy in patients who develop GH deficiency (GHD) after cure of acromegaly have not been established in a placebo-controlled study. OBJECTIVE The objective of the study was to determine whether GH replacement improves body composition, cardiovascular risk markers and quality of life in patients with GHD and prior acromegaly. DESIGN This was a 6-month, randomized, placebo-controlled study. SETTING The study was conducted at a clinical translational science center. STUDY PARTICIPANTS Participants included 30 subjects with prior acromegaly and current GHD. INTERVENTION INTERVENTIONs included GH or placebo. MAIN OUTCOME MEASURES Body composition (dual-energy x-ray absorptiometry and cross-sectional computed tomography at L4), cardiovascular risk markers (high-sensitivity C-reactive protein (hsCRP), total, high-density lipoprotein and low-density lipoprotein cholesterol, fibrinogen, and carotid intimal-medial thickness), and quality of life were measured. RESULTS The mean GH dose at 6 months was 0.58 +/- 0.26 mg/d. Total fat mass, visceral adipose tissue (-15.3 +/- 18.6 vs. 1.3 +/- 12.5%, P = 0.01), and total abdominal fat decreased, and fat-free mass increased, in the GH vs. placebo group. Mean hsCRP levels decreased, but there was no GH effect on other cardiovascular risk markers. There was no change in glycosylated hemoglobin or homeostasis model assessment insulin resistance index. Quality of life improved with GH. Side effects were minimal. CONCLUSIONS This is the first randomized, placebo-controlled study of the effects of GH replacement therapy on body composition and cardiovascular end points in patients who have developed GH deficiency after treatment for acromegaly, a disease complicated by metabolic and body composition alterations and increased cardiovascular risk. GH replacement decreased visceral adipose tissue, increased fat-free mass, decreased hsCRP, and improved quality of life in patients with GHD after cure of acromegaly, with minimal side effects and without an increase in insulin resistance.


The Journal of Clinical Endocrinology and Metabolism | 2008

Growth Hormone Deficiency by Growth Hormone Releasing Hormone-Arginine Testing Criteria Predicts Increased Cardiovascular Risk Markers in Normal Young Overweight and Obese Women

Andrea L. Utz; Ami Yamamoto; Linda C. Hemphill; Karen K. Miller

CONTEXT Little is known about the relationship between GH and cardiovascular risk markers in women without organic hypothalamic/pituitary disease. OBJECTIVE The objective of the study was to determine whether healthy young overweight and obese women, who would be classified as having GH deficiency (GHD) based on standard criteria used in hypopituitarism (peak GH after stimulation with GHRH and arginine < 5 ng/ml), have increased cardiovascular risk markers. DESIGN This was a cross-sectional study. SETTING The study was conducted at the General Clinical Research Center. STUDY PARTICIPANTS Forty-five women of reproductive age, mean age 33.1 +/- 1.2 yr and mean body mass index (BMI) 30.9 +/- 1.0 kg/m(2). INTERVENTION There was no intervention. MAIN OUTCOME MEASURES Measures included carotid intima-medial thickness, high-sensitivity C-reactive protein (hsCRP), total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein, triglycerides, E-selectin, soluble intercellular adhesion molecule-1, TNF-alpha receptor I, TNF-alpha receptor II, fasting insulin levels, and oral glucose tolerance testing. RESULTS Twenty-six percent of overweight or obese subjects and none with BMI less than 25 kg/m(2) met criteria for GHD. Subjects who met GHD criteria had a mean BMI of 37.0 +/- 1.7 kg/m(2) (range 28.6-43.6 kg/m(2)), and their mean waist circumference (110.1 +/- 3.5 cm) was higher than in overweight/obese women with GH sufficiency (P = 0.007). Mean carotid intima-media thickness, hsCRP, soluble intercellular adhesion molecule-1, TNF-alpha receptor I, and TNF-alpha receptor II levels were higher, and HDL lower, in women meeting GHD criteria than in GH sufficiency. Differences in HDL, hsCRP, and TNF-alpha receptor II remained after controlling for age plus BMI, waist circumference, or trunk fat. There were no differences in measures of insulin resistance. CONCLUSIONS There may be a relative GHD syndrome in overweight and obese women without organic pituitary or hypothalamic disease that confers increased cardiovascular risk, independent of weight.


Journal of the American College of Cardiology | 2014

Nonpharmacological Lipoprotein Apheresis Reduces Arterial Inflammation in Familial Hypercholesterolemia

Diederik F. van Wijk; Barbara Sjouke; Amparo L. Figueroa; Hamed Emami; Fleur M. van der Valk; Megan H. MacNabb; Linda C. Hemphill; Dominik M. Schulte; Marion G. Koopman; Mark E. Lobatto; Hein J. Verberne; Zahi A. Fayad; John J. P. Kastelein; Willem J. M. Mulder; G. Kees Hovingh; Ahmed Tawakol; Erik S.G. Stroes

BACKGROUND Patients with familial hypercholesterolemia (FH) are characterized by elevated atherogenic lipoprotein particles, predominantly low-density lipoprotein cholesterol (LDL-C), which is associated with accelerated atherogenesis and increased cardiovascular risk. OBJECTIVES This study used (18)F-fluorodeoxyglucose positron emission tomography ((18)FDG-PET) to investigate whether arterial inflammation is higher in patients with FH and, moreover, whether lipoprotein apheresis attenuates arterial wall inflammation in FH patients. METHODS In total, 38 subjects were recruited: 24 FH patients and 14 normolipidemic controls. All subjects underwent FDG-PET imaging at baseline. Twelve FH patients who met the criteria for lipoprotein apheresis underwent apheresis procedures followed by a second FDG-PET imaging 3 days (range 1 to 4 days) after apheresis. Subsequently, the target-to-background ratio (TBR) of FDG uptake within the arterial wall was assessed. RESULTS In FH patients, the mean arterial TBR was higher compared with healthy controls (2.12 ± 0.27 vs. 1.92 ± 0.19; p = 0.03). A significant correlation was observed between baseline arterial TBR and LDL-C (R = 0.37; p = 0.03) that remained significant after adjusting for statin use (β = 0.001; p = 0.02) and atherosclerosis risk factors (β = 0.001; p = 0.03). LDL-C levels were significantly reduced after lipoprotein apheresis (284 ± 118 mg/dl vs. 127 ± 50 mg/dl; p < 0.001). There was a significant reduction of arterial inflammation after lipoprotein apheresis (TBR: 2.05 ± 0.31 vs. 1.91 ± 0.33; p < 0.02). CONCLUSIONS The arterial wall of FH patients is characterized by increased inflammation, which is markedly reduced after lipoprotein apheresis. This lends support to a causal role of apoprotein B-containing lipoproteins in arterial wall inflammation and supports the concept that lipoprotein-lowering therapies may impart anti-inflammatory effects by reducing atherogenic lipoproteins.


AIDS | 2012

Effects of lifestyle modification and metformin on atherosclerotic indices among HIV-infected patients with the metabolic syndrome.

Kathleen V. Fitch; Suhny Abbara; Hang Lee; Eleni Stavrou; Rachel Sacks; Theresa Michel; Linda C. Hemphill; Martin Torriani; Steven Grinspoon

Objective:Metabolic abnormalities including diabetes, dyslipidemia, hypertension, and abdominal obesity occur commonly in HIV patients, are associated with increased coronary artery calcification (CAC), and contribute to increased cardiovascular disease (CVD) in this population. We hypothesized that lifestyle modification (LSM) and metformin would improve CVD indices in HIV patients with metabolic syndrome. Design:A randomized, placebo-controlled trial to investigate LSM and metformin, alone and in combination, over 1 year, among 50 HIV-infected patients with metabolic syndrome. Methods:We assessed CAC, cardiovascular and metabolic indices. Results:Among the participants, duration of HIV-infection was 14 ± 1 year and duration of antiretroviral therapy was 6 ± 1 year. Metformin-treated patients demonstrated significantly less progression of CAC (−1 ± 2 vs. 33 ± 17, P = 0.004, metformin vs. placebo), whereas the effect of LSM on CAC progression was not significant (8 ± 6 vs. 21 ± 14, P = 0.82, LSM vs. no-LSM). Metformin had a significantly greater effect on CAC than LSM (P = 0.01). Metformin-treated patients also demonstrated less progression in calcified plaque volume (−0.4 ± 1.9 vs. 27.6 ± 13.8 &mgr;l, P = 0.008) and improved homeostatic model of assessment-insulin resistance (HOMA-IR) (P = 0.05) compared with placebo. Participants randomized to LSM vs. no-LSM showed significant improvement in HDL (P = 0.03), high-sensitivity C-reactive protein (hsCRP) (P = 0.05), and cardiorespiratory fitness. Changes in CAC among the four groups – no-LSM–placebo (43 ± 30); LSM–placebo (19 ± 7); no-LSM–metformin (1 ± 1) and LSM–metformin (−4 ± 6) – were different (P = 0.03 for ANOVA and linear trend across groups), and the majority of this effect was mediated by metformin. Results are mean ± SEM. Conclusion:Metformin prevents plaque progression in HIV-infected patients with the metabolic syndrome.


Circulation-cardiovascular Genetics | 2016

Treatment Gaps in Adults with Heterozygous Familial Hypercholesterolemia in the United States: Data from the CASCADE-FH Registry

Emil M. deGoma; Zahid Ahmad; Emily C. O’Brien; Iris Kindt; Peter Shrader; Connie B. Newman; Yashashwi Pokharel; Seth J. Baum; Linda C. Hemphill; Lisa C. Hudgins; Catherine D. Ahmed; Samuel S. Gidding; Danielle Duffy; William A. Neal; Katherine Wilemon; Matthew T. Roe; Daniel J. Rader; Christie M. Ballantyne; MacRae F. Linton; P. Barton Duell; Michael D. Shapiro; Patrick M. Moriarty; Joshua W. Knowles

Background— Cardiovascular disease burden and treatment patterns among patients with familial hypercholesterolemia (FH) in the United States remain poorly described. In 2013, the FH Foundation launched the Cascade Screening for Awareness and Detection (CASCADE) of FH Registry to address this knowledge gap. Methods and Results— We conducted a cross-sectional analysis of 1295 adults with heterozygous FH enrolled in the CASCADE-FH Registry from 11 US lipid clinics. Median age at initiation of lipid-lowering therapy was 39 years, and median age at FH diagnosis was 47 years. Prevalent coronary heart disease was reported in 36% of patients, and 61% exhibited 1 or more modifiable risk factors. Median untreated low-density lipoprotein cholesterol (LDL-C) was 239 mg/dL. At enrollment, median LDL-C was 141 mg/dL; 42% of patients were taking high-intensity statin therapy and 45% received >1 LDL-lowering medication. Among FH patients receiving LDL-lowering medication(s), 25% achieved an LDL-C <100 mg/dL and 41% achieved a ≥50% LDL-C reduction. Factors associated with prevalent coronary heart disease included diabetes mellitus (adjusted odds ratio 1.74; 95% confidence interval 1.08–2.82) and hypertension (2.48; 1.92–3.21). Factors associated with a ≥50% LDL-C reduction from untreated levels included high-intensity statin use (7.33; 1.86–28.86) and use of >1 LDL-lowering medication (1.80; 1.34–2.41). Conclusions— FH patients in the CASCADE-FH Registry are diagnosed late in life and often do not achieve adequate LDL-C lowering, despite a high prevalence of coronary heart disease and risk factors. These findings highlight the need for earlier diagnosis of FH and initiation of lipid-lowering therapy, more consistent use of guideline-recommended LDL-lowering therapy, and comprehensive management of traditional coronary heart disease risk factors.

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Daniel J. Rader

University of Pennsylvania

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MacRae F. Linton

Vanderbilt University Medical Center

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