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Biomedical subjects

Joan T Merrill

Publications and source records attributed to Joan T Merrill.

At least 19 recordsLinked to original sources
PubMed2006

The prevalence and clinical significance of antiphospholipid antibodies in rheumatoid arthritis.

Published data were reviewed to evaluate the occurrence of antiphospholipid antibodies (aPL) in rheumatoid arthritis (RA) patients and to investigate their clinical relevance in this population. The mean prevalence was calculated at 28% and the median was 22%. Few studies have found a relationship between aPL antibodies and thrombosis, particularly in combination with other risk factors. Conflicting results have been reported on the association of anticardiolipin (aCL) antibody positivity and neurologic symptoms, Reynaud's phenomenon, disease activity, radiographic erosions, extra-articular RA manifestations, rheumatoid factor, and atherosclerosis. Some studies, however, suggest that there is a correlation present between those antibodies and C-reactive protein levels, rheumatoid nodules, and antinuclear antibodies. TNF-alpha blocking agents may cause an induction of aCL antibodies, but it seems like they do not cause any clinical features related to the antiphospholipid syndrome. Higher 17beta-estradiol levels were observed in aCL antibody-positive RA patients than in aCL antibody-negative patients and especially in premenopausal women, which may predispose to a more efficient immune response.

Antibodies, Antiphospholipid↗
PubMed2006

Do antiphospholipid antibodies develop for a purpose?

There is a growing body of literature suggesting that antiphospholipid antibodies develop for a purpose, that they play several key roles in the innate immune response, and are only rendered pathologic in susceptible people under adverse intravascular conditions. This paper will review evidence that the autoantibodies associated with the antiphospholipid syndrome develop from natural autoantibodies for purposes that are beneficial to host defense, and are only rendered pathologic as a result of adverse intravascular events.

Antibodies, Antiphospholipid↗
PubMed2006

Catastrophic antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is a thrombotic disorder associated with autoantibodies that target membrane phospholipids and phospholipid-binding proteins, which regulate coagulation. APS is usually characterized by major arterial or venous occlusions, pregnancy complications, or both. In 1992, Asherson described an unusual variant of APS termed the catastrophic antiphospholipid syndrome (also known as Asherson's syndrome), the hallmark of which is rapid multiorgan failure caused by widespread small-vessel thrombi. Empiric treatments have improved the prognosis of patients, but half still die from thrombotic diathesis, even though those who survive the acute stages frequently remain well. Given the persistently high mortality rate, efforts have been underway to facilitate early diagnosis, institute effective treatments in a timely manner and to better understand the cause (or causes) of this extreme condition in order to improve outcomes.

Anemia, Hemolytic↗
PubMed2005

Combined oral contraceptives in women with systemic lupus erythematosus.

BACKGROUND: Oral contraceptives are rarely prescribed for women with systemic lupus erythematosus, because of concern about potential negative side effects. In this double-blind, randomized, noninferiority trial, we prospectively evaluated the effect of oral contraceptives on lupus activity in premenopausal women with systemic lupus erythematosus. METHODS: A total of 183 women with inactive (76 percent) or stable active (24 percent) systemic lupus erythematosus at 15 U.S. sites were randomly assigned to receive either oral contraceptives (triphasic ethinyl estradiol at a dose of 35 microg plus norethindrone at a dose of 0.5 to 1 mg for 12 cycles of 28 days each; 91 women) or placebo (92 women) and were evaluated at months 1, 2, 3, 6, 9, and 12. Subjects were excluded if they had moderate or high levels of anticardiolipin antibodies, lupus anticoagulant, or a history of thrombosis. RESULTS: The primary end point, a severe lupus flare, occurred in 7 of 91 subjects receiving oral contraceptives (7.7 percent) as compared with 7 of 92 subjects receiving placebo (7.6 percent). The 12-month rates of severe flare were similar: 0.084 for the group receiving oral contraceptives and 0.087 for the placebo group (P=0.95; upper limit of the one-sided 95 percent confidence interval for this difference, 0.069, which is within the prespecified 9 percent margin for noninferiority). Rates of mild or moderate flares were 1.40 flares per person-year for subjects receiving oral contraceptives and 1.44 flares per person-year for subjects receiving placebo (relative risk, 0.98; P=0.86). In the group that was randomized to receive oral contraceptives, there was one deep venous thrombosis and one clotted graft; in the placebo group, there was one deep venous thrombosis, one ocular thrombosis, one superficial thrombophlebitis, and one death (after cessation of the trial). CONCLUSIONS: Our study indicates that oral contraceptives do not increase the risk of flare among women with systemic lupus erythematosus whose disease is stable.

Adolescent↗
PubMed2005

Mycophenolate mofetil or intravenous cyclophosphamide for lupus nephritis.

BACKGROUND: Since anecdotal series and small, prospective, controlled trials suggest that mycophenolate mofetil may be effective for treating lupus nephritis, larger trials are desirable. METHODS: We conducted a 24-week randomized, open-label, noninferiority trial comparing oral mycophenolate mofetil (initial dose, 1000 mg per day, increased to 3000 mg per day) with monthly intravenous cyclophosphamide (0.5 g per square meter of body-surface area, increased to 1.0 g per square meter) as induction therapy for active lupus nephritis. A change to the alternative regimen was allowed at 12 weeks in patients who did not have an early response. The study protocol specified adjunctive care and the use and tapering of corticosteroids. The primary end point was complete remission at 24 weeks (normalization of abnormal renal measurements and maintenance of baseline normal measurements). A secondary end point was partial remission at 24 weeks. RESULTS: Of 140 patients recruited, 71 were randomly assigned to receive mycophenolate mofetil and 69 were randomly assigned to receive cyclophosphamide. At 12 weeks, 56 patients receiving mycophenolate mofetil and 42 receiving cyclophosphamide had satisfactory early responses. In the intention-to-treat analysis, 16 of the 71 patients (22.5 percent) receiving mycophenolate mofetil and 4 of the 69 patients receiving cyclophosphamide (5.8 percent) had complete remission, for an absolute difference of 16.7 percentage points (95 percent confidence interval, 5.6 to 27.9 percentage points; P=0.005), meeting the prespecified criteria for noninferiority and demonstrating the superiority of mycophenolate mofetil to cyclophosphamide. Partial remission occurred in 21 of the 71 patients (29.6 percent) and 17 of the 69 patients (24.6 percent), respectively (P=0.51). Three patients assigned to cyclophosphamide died, two during protocol therapy. Fewer severe infections and hospitalizations but more diarrhea occurred among those receiving mycophenolate. CONCLUSIONS: In this 24-week trial, mycophenolate mofetil was more effective than intravenous cyclophosphamide in inducing remission of lupus nephritis and had a more favorable safety profile.

Administration, Oral↗
PubMed2005

The effect of combined estrogen and progesterone hormone replacement therapy on disease activity in systemic lupus erythematosus: a randomized trial.

BACKGROUND: There is concern that exogenous female hormones may worsen disease activity in women with systemic lupus erythematosus (SLE). OBJECTIVE: To evaluate the effect of hormone replacement therapy (HRT) on disease activity in postmenopausal women with SLE. DESIGN: Randomized, double-blind, placebo-controlled noninferiority trial conducted from March 1996 to June 2002. SETTING: 16 university-affiliated rheumatology clinics or practices in 11 U.S. states. PATIENTS: 351 menopausal patients (mean age, 50 years) with inactive (81.5%) or stable-active (18.5%) SLE. INTERVENTIONS: 12 months of treatment with active drug (0.625 mg of conjugated estrogen daily, plus 5 mg of medroxyprogesterone for 12 days per month) or placebo. The 12-month follow-up rate was 82% for the HRT group and 87% for the placebo group. MEASUREMENTS: The primary end point was occurrence of a severe flare as defined by Safety of Estrogens in Lupus Erythematosus, National Assessment-Systemic Lupus Erythematosus Disease Activity Index composite. RESULTS: Severe flare was rare in both treatment groups: The 12-month severe flare rate was 0.081 for the HRT group and 0.049 for the placebo group, yielding an estimated difference of 0.033 (P = 0.23). The upper limit of the 1-sided 95% CI for the treatment difference was 0.078, within the prespecified margin of 9% for noninferiority. Mild to moderate flares were significantly increased in the HRT group: 1.14 flares/person-year for HRT and 0.86 flare/person-year for placebo (relative risk, 1.34; P = 0.01). The probability of any type of flare by 12 months was 0.64 for the HRT group and 0.51 for the placebo group (P = 0.01). In the HRT group, there were 1 death, 1 stroke, 2 cases of deep venous thrombosis, and 1 case of thrombosis in an arteriovenous graft; in the placebo group, 1 patient developed deep venous thrombosis. LIMITATIONS: Findings are not generalizable to women with high-titer anticardiolipin antibodies, lupus anticoagulant, or previous thrombosis. CONCLUSIONS: Adding a short course of HRT is associated with a small risk for increasing the natural flare rate of lupus. Most of these flares are mild to moderate. The benefits of HRT can be balanced against the risk for flare because HRT did not significantly increase the risk for severe flare compared with placebo.

Adolescent↗
PubMed2005

The role of biomarkers in the assessment of lupus.

Although considered a prototypic autoimmune disease, the hallmark of systemic lupus erythematosus (SLE) is its heterogeneity. Accordingly, manifestations can vary widely from person to person, with the potential involvement of virtually any bodily organ. Furthermore, the genetic abnormalities underlying this condition are complicated, with diverse genetic polymorphisms described in different ethnic groups, strongly suggesting that the actual pathology underlying the immunologic disarray might not be the same for each patient. Evolving concepts of genetics and immunity have clarified that patients can carry unique arrays of exacerbating and protective factors. These factors, in conjunction with variable environmental triggers for SLE, probably determine the sequelae that an individual experiences. Therefore, it is not surprising that the clinical manifestations are diverse, the temporal sequence of organ involvement often unpredictable, and that the flares of inflammatory activity that characterize SLE can either remit without consequence or leave permanent damage in their wake. It is widely accepted that the current standard of care for SLE patients is inadequate. Programs to develop and test new drug and/or device therapies have been ongoing since the mid-1990s but have encountered formidable obstacles. With the current burst of drug discovery and the advent of several large international trials of promising new agents, the challenge to overcome these obstacles has never been greater. A burgeoning literature in the past decades nevertheless suggests that despite the complexities of the many immunologic pathways that impact on SLE, characteristic biologic markers are emerging as potential signposts that can characterize patient subgroups, predict prognosis, mark the exacerbations and remissions of SLE flares, and serve as endpoints in the determination of the dosing and timing of immune-modulating treatments. Several of the promising biomarkers are addressed in this chapter.

Biomarkers↗
PubMed2005

Computer-assisted pattern recognition of autoantibody results.

Immunoassay-based anti-nuclear antibody (ANA) screens are increasingly used in the initial evaluation of autoimmune disorders, but these tests offer no "pattern information" comparable to the information from indirect fluorescence assay-based screens. Thus, there is no indication of "next steps" when a positive result is obtained. To improve the utility of immunoassay-based ANA screening, we evaluated a new method that combines a multiplex immunoassay with a k nearest neighbor (kNN) algorithm for computer-assisted pattern recognition. We assembled a training set, consisting of 1,152 sera from patients with various rheumatic diseases and non-diseased patients. The clinical sensitivity and specificity of the multiplex method and algorithm were evaluated with a test set that consisted of 173 sera collected at a rheumatology clinic from patients diagnosed by using standard criteria, as well as 152 age- and sex-matched sera from presumably healthy individuals (sera collected at a blood bank). The test set was also evaluated with a HEp-2 cell-based enzyme-linked immunosorbent assay (ELISA). Both the ELISA and multiplex immunoassay results were positive for 94% of the systemic lupus erythematosus (SLE) patients. The kNN algorithm correctly proposed an SLE pattern for 84% of the antibody-positive SLE patients. For patients with no connective tissue disease, the multiplex method found fewer positive results than the ELISA screen, and no disease was proposed by the kNN algorithm for most of these patients. In conclusion, the automated algorithm could identify SLE patterns and may be useful in the identification of patients who would benefit from early referral to a specialist, as well as patients who do not require further evaluation.

Algorithms↗
PubMed2005

Emergence of targeted immune therapies for systemic lupus.

Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease, characterised by flares of rampant inflammation that can threaten, in an unpredictable manner, almost any organ in the body. Current standard of care is largely empiric, involving the use of corticosteroids and toxic immune suppressive agents that are widely acknowledged to have unacceptable side effects for long-term use. Recently, there have been significant advances in understanding the nature of some fundamental immune imbalances underlying the complicated clinical manifestations of SLE. Nevertheless attempts to develop and test more targeted, and potentially safer immune-modulating drugs for lupus have encountered significant obstacles, due to the lack of validated biological markers for disease flare and remission, and difficulties in the clinical assessment of the heterogeneous patients. In support of renewed interest in drug development for lupus, large collaborative groups have formed, and efforts are underway to develop objective biomarkers for SLE as well as to improve the standardisation and reproducibility of clinical outcome measures in multi-centre trials.

Drug Delivery Systems↗
PubMed2005

DHEA supplementation: the claims in perspective.

Deficiency of dehydroepiandrosterone (DHEA) is associated with lupus erythematosus, diabetes mellitus, Alzheimer disease, and some cancers, but we are not yet ready to conclude that prescribing supplemental DHEA is helpful in these or any other conditions. DHEA shows some promise in observational clinical studies and laboratory experiments, but we still need large-scale human studies to answer key questions. For now, we do not have enough evidence to recommend routine treatment with DHEA. As with other supplements, quality control is always a concern, and different brands may contain different amounts of active ingredient.

Adjuvants, Immunologic↗
PubMed2004

Effects of prasterone on disease activity and symptoms in women with active systemic lupus erythematosus.

OBJECTIVE: To determine whether prasterone administration results in improvement or stabilization of systemic lupus erythematosus (SLE) disease activity and its symptoms. METHODS: Women with active SLE were treated with prasterone 200 mg/day plus standard SLE treatments or with placebo plus standard SLE treatments for up to 12 months in this randomized, double-blind investigation conducted at 27 centers. Standard SLE treatments included prednisone (</=10 mg/day), antimalarials, and immunosuppressive agents; dosages were required to be stable for >/=6 weeks prior to enrollment and remain unchanged during protocol treatment. Responders were patients who experienced no clinical deterioration and had improvement or stabilization over the duration of the study in 2 disease activity measures (the SLE Disease Activity Index [SLEDAI] and the Systemic Lupus Activity Measure) and 2 quality of life measures (patient's global assessment and the Krupp Fatigue Severity Scale). RESULTS: A total of 381 women with SLE were enrolled. Among patients with clinically active disease at baseline (SLEDAI score >2), 86 of 147 in the prasterone group (58.5%) demonstrated improvement or stabilization without clinical deterioration, as compared with 65 of 146 in the placebo group (44.5%) (P = 0.017). Acne and hirsutism were reported in 33% and 16%, respectively, of the prasterone group and in 14% and 2%, respectively, of the placebo group (P < 0.05 for both comparisons). However, most cases of acne and hirsutism were mild and did not require withdrawal from therapy. Myalgias and oral stomatitis were reported less frequently in the prasterone group (22% and 15%, respectively) than in the placebo group (36% and 23%, respectively) (P < 0.05 for both comparisons). Serum levels of high-density lipoprotein cholesterol, triglycerides, and C3 complement significantly decreased, while levels of testosterone and, to a lesser extent, estradiol increased in the prasterone group. CONCLUSION: In adult women with active SLE, administration of prasterone at a dosage of 200 mg/day improved or stabilized signs and symptoms of disease and was generally well tolerated.

Adjuvants, Immunologic↗
PubMed2004

Genetics of antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by recurrent arterial or venous thrombosis or fetal loss and the presence of antiphospholipid antibodies (aPL). Genetic factors are thought to play a role in the susceptibility to APS. Similar to many other polygenic autoimmune diseases, human leukocyte antigen associations have been reported. The genetics of b(2)-glycoprotein I, one of the most representative target antigens of aPL, has been extensively studied. Additional genetic risk factors for the development of thrombosis in patients with aPL have also been discussed. However, the genes involved in APS have not been identified because antigen specificity of aPL and the pathophysiology of APS are highly heterogeneous and multifactorial. Genome-wide linkage analysis and larger cohort studies would lead to better understanding of the genes that might be involved in APS.

Antiphospholipid Syndrome↗
PubMed2004

Diagnosis of the antiphospholipid syndrome: how far to go?

The past decade has seen an evolution in the way that thrombophilic conditions are diagnosed and understood. This has largely evolved through the detection of single nucleotide polymorphisms in critical regulating proteins that are thought to confer significant structural-functional changes at key points in the coagulation cascade. The antiphospholipid syndrome (APS) is a complex hypercoagulable disorder that as yet defies the possibility of simple, predictive testing.

Antibodies, Antiphospholipid↗
PubMed2004

Challenges in bringing the bench to bedside in drug development for SLE.

It is now widely accepted that the current standard of care for systemic lupus erythematosus (SLE) patients is inadequate. There has not been a new medication approved for this disease in thirty years. Attempts to develop and test new drugs have been ongoing since the mid-1990s, but have encountered formidable obstacles. Current models for lupus pathogenesis have provided a theoretical framework for understanding how heterogeneous genetic defects might combine in various ways to increase susceptibility to SLE in different individuals, and could have important implications for new drug development. With the current burst of drug discovery and increased public awareness of SLE, the impetus to overcome these obstacles has never been greater.

Animals↗
PubMed2004

Anti-beta 2-glycoprotein I and antiphosphatidylserine antibodies are predictors of arterial thrombosis in patients with antiphospholipid syndrome.

The predictive value (PV) and association of 4 antiphospholipid antibodies with clinical manifestations of the antiphospholipid syndrome (APS) were evaluated in 90 patients with systemic lupus erythematosus (SLE) and 100 with APS. Patients with APS were classified into arterial thrombosis, venous thrombosis, and pregnancy morbidity subgroups. IgG, IgM, and IgA anticardiolipin (aCL), antiphosphatidylserine (aPS), anti-beta 2-glycoprotein I (anti-B2GPI), and antiprothrombin (aPT) antibodies were determined by enzyme-linked immunosorbent assay. Individually, anti-B2GPI and aPS antibodies had the strongest PV for APS (86.4%-94.1%; P < .001) in patients with SLE. The PV for APS reached 100% when 2 or more antibodies were present. Similarly, anti-B2GPI and aPS antibodies had a stronger PV and association for arterial thrombosis (87%-95%; P < .001) compared with venous thrombosis (80%-92%; P = .01). Weak PV and association with pregnancy morbidity were seen with all antibodies. These results suggest an important pathogenic role of anti-B2GPI antibodies in arterial thrombosis. In addition, anti-B2GPI and aPS antibodies seem to provide the best diagnostic value for the laboratory assessment of APS.

Abortion, Spontaneous↗
PubMed2004

Defining response in systemic lupus erythematosus: a study by the Systemic Lupus International Collaborating Clinics group.

OBJECTIVE: In a preliminary attempt to develop a drug responder index for patients with systemic lupus erythematosus (SLE), 2 validated disease activity instruments were studied for their responsiveness and compared to a physician visual analog scale (VAS) assessment of disease activity. We attempted to determine whether these validated instruments were useful components in characterizing response in the setting of a clinical trial. METHODS: Eighty paper patients were assessed using the British Isles Lupus Assessment Group (BILAG) and Systemic Lupus Disease Activity Index (SLEDAI) and by physician's assessment of global activity. The cases were arranged in random order and divided into groups of 20 patients and each group was assessed by 20 lupus experts; change in disease activity was recorded at 3 and 6 months compared to baseline using a physician VAS. RESULTS: Four different lupus experts assessed disease activity in all 80 patients at baseline and 3 and 6 months after initiation of therapy using the BILAG and SLEDAI instruments. BILAG and SLEDAI scores correlated well over time; however, in a regression analysis where average physician VAS were chosen as the outcome variable, a significant amount of variation in the average physician VAS not related to the SLEDAI and BILAG scores was noted. CONCLUSION: The physician VAS may be too blunt to assess response in SLE, because even among experienced lupus assessors, there were considerable differences in what influenced scoring decisions.

Adult↗