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E William St Clair

Publications and source records attributed to E William St Clair.

At least 19 recordsLinked to original sources
PubMed2007

New reagents on the horizon for immune tolerance.

Recent advances in immunology and a growing arsenal of new drugs are bringing the focus of tolerance research from animal models into the clinical setting. The conceptual framework for therapeutic tolerance induction has shifted from a "sledgehammer" approach that relies solely on cellular depletion and cytokine targeting, to a strategy directed toward restoring a functional balance across the immune system, namely the different populations of naive cells, effector and memory cells, and regulatory cells. Unlocking the key to tolerance induction in the future will likely depend on our ability to harness the functions of T regulatory cells. Also, dendritic cells are strategically positioned at the interface between innate and adaptive immunity and may be subject to deliberate medical intervention in a way that can control a chronic inflammatory response. Many reagents with tolerance-inducing potential are currently undergoing clinical testing in transplantation, autoimmune diseases, and allergic diseases, and even more that are on the horizon promise to offer enormous benefits to human health.

Autoimmune Diseases↗
PubMed2006

Infliximab treatment maintains employability in patients with early rheumatoid arthritis.

OBJECTIVE: To evaluate the impact of infliximab therapy on the employment status of patients with early rheumatoid arthritis (RA). METHODS: Methotrexate (MTX)-naive patients with active early RA were randomly allocated to receive MTX plus placebo or MTX plus infliximab (3 mg/kg or 6 mg/kg) at weeks 0, 2, and 6 and then every 8 weeks through week 46. Data for patients younger than age 65 years were included in the analyses. A patient was categorized as employable if he or she was employed or felt well enough to work if a job were available. RESULTS: The change in actual employment was not significantly different between patients receiving MTX plus infliximab and those receiving MTX plus placebo (0.5% versus 1.3%; P > 0.5). However, the proportion of patients whose status changed from employable at baseline to unemployable at week 54 was smaller in the group receiving MTX plus infliximab compared with that in the group receiving MTX alone (8% versus 14%; P = 0.05). Patients who were treated with infliximab plus MTX had a significantly greater likelihood of improvement rather than deterioration in employability (odds ratio 2.4; P < 0.001); this likelihood was not significantly greater in patients receiving MTX alone. The proportion of employed patients who lost workdays during the trial was smaller in the MTX plus infliximab group than in the MTX-alone group (P = 0.010). CONCLUSION: The actual employment rates among patients in the 2 treatment groups were not different. However, patients with early RA who were treated with MTX plus infliximab had a higher probability of maintaining their employability compared with those who were treated with MTX alone.

Antibodies, Monoclonal↗
PubMed2006

Predictors of joint damage in patients with early rheumatoid arthritis treated with high-dose methotrexate with or without concomitant infliximab: results from the ASPIRE trial.

OBJECTIVE: To identify disease characteristics leading to progression of joint damage in patients with early rheumatoid arthritis (RA) treated with methotrexate (MTX) versus those treated with infliximab plus MTX. METHODS: Patients who had not previously been treated with MTX with active RA were randomly assigned to receive escalating doses of MTX up to 20 mg/week plus placebo or infliximab at weeks 0, 2, and 6, and every 8 weeks thereafter through week 46. Radiographic joint damage was assessed using the modified Sharp/van der Heijde score (SHS). The relationship between disease activity measures at baseline and week 14, as well as those averaged over time, were examined in relation to the change in SHS from baseline through week 54. RESULTS: C-reactive protein (CRP) levels, erythrocyte sedimentation rate (ESR), and swollen joint count were associated with greater joint damage progression in the MTX-only group, while none of these parameters was associated with progression in the infliximab plus MTX group. Mean changes in SHS among patients in the highest CRP (> or = 3 mg/dl) and ESR (> or = 52 mm/hour) tertiles in the MTX-only group were 5.62 and 5.89, respectively, compared with 0.73 and 1.12 in the infliximab plus MTX group (P < 0.001). Patients with greater joint damage at baseline (SHS > or = 10.5) showed less progression with infliximab plus MTX compared with MTX alone (-0.39 versus 4.11; P < 0.001). Patients receiving MTX alone who had persistently active disease at week 14 showed greater radiographic progression of joint damage than those taking MTX plus infliximab. CONCLUSION: High CRP level, high ESR, or persistent disease activity was associated with greater radiographic progression in the group taking MTX alone, while little radiographic progression was seen in patients receiving both MTX and infliximab, regardless of the abnormal levels of these traditional predictors.

Adolescent↗
PubMed2006

Solid malignancies among patients in the Wegener's Granulomatosis Etanercept Trial.

OBJECTIVE: Etanercept is a soluble fusion protein designed to inhibit tumor necrosis factor (TNF). During the Wegener's Granulomatosis Etanercept Trial (WGET), a placebo-controlled trial of etanercept given in addition to standard therapy for remission induction and maintenance, more solid malignancies were observed in the etanercept group than in the group treated with standard therapy alone. This study was undertaken to further explore the potential association between anti-TNF therapy and the development of malignancy in these patients. METHODS: One hundred eighty patients with active WG were enrolled and followed up for a median of 27 months. At enrollment, disease characteristics, treatment history, specific medical history items, and information about previous WG treatments and risk factors for malignancy were recorded. During the trial, the occurrence of malignancies and other adverse events was recorded prospectively. RESULTS: All 6 solid malignancies observed during the WGET occurred in the etanercept group (P = 0.01 versus placebo group); based on a comparison of age- and sex-specific incidence rates, 1.92 solid malignancies would have been expected in this group. The solid malignancies included 2 cases of mucinous adenocarcinoma of the colon, 1 each of metastatic cholangiocarcinoma, renal cell carcinoma, and breast carcinoma, and 1 recurrent liposarcoma. There were no differences between the 2 treatment groups in sex distribution, disease severity, personal or family history of cancer, or tobacco and alcohol use. The etanercept group was older at baseline and less likely to be newly diagnosed with WG at the time of randomization. Patients who developed solid tumors were older than patients who did not. All etanercept-treated patients who developed solid tumors were also treated with cyclophosphamide during the trial. However, there were no differences between the groups in the amount of cyclophosphamide received during the trial or the percentage who had received cyclophosphamide before enrollment. There were also no differences in the mean duration of daily cyclophosphamide therapy or the maximum daily cyclophosphamide dosage before enrollment. CONCLUSION: Data from the WGET, the first substantial reported experience of the combined use of etanercept and cyclophosphamide in the treatment of WG, indicate that the combination of TNF inhibition and cyclophosphamide may heighten the risk of cancer beyond that observed with cyclophosphamide alone.

Aged↗
PubMed2006

IgG and IgM anticardiolipin antibodies following treatment with infliximab plus methotrexate in patients with early rheumatoid arthritis.

OBJECTIVE: To assess the occurrence of anticardiolipin antibodies (aCL) in patients with early rheumatoid arthritis (RA) receiving treatment with infliximab plus methotrexate (MTX) versus MTX alone. METHODS: The first 299 patients enrolled in the randomized, Active-Controlled Study of Patients Receiving Infliximab for the Treatment of Rheumatoid Arthritis of Early Onset (ASPIRE) trial who had baseline (week 0) samples available for aCL testing were included in this study. Sera were collected at weeks 0, 30, and 54 from 110 patients taking infliximab 3 mg/kg plus MTX, 98 patients taking infliximab 6 mg/kg plus MTX, and 91 patients taking placebo plus MTX. IgG and IgM aCL were measured using an anticardiolipin assay. RESULTS: IgG and IgM aCL positivity at baseline was similar in all treatment groups. Most patients were negative for IgG aCL at baseline and remained so at the last followup evaluation. One percent (2 of 208) of patients who received infliximab plus MTX and were negative for IgG aCL at baseline were positive for IgG aCL at weeks 30 and 54. A slightly higher proportion of patients who received infliximab plus MTX and were negative for IgM aCL at baseline were positive for IgM aCL at weeks 30 and 54 (4.8% [10 of 208]) as compared with patients who received placebo plus MTX (1.1% [1 of 91]), but the difference was not significant. CONCLUSION: There was a low incidence of the development of aCL in patients with early RA who received infliximab in combination with MTX, and the difference was not significant compared with patients who received placebo plus MTX.

Adult↗
PubMed2006

CTLA4Ig: bridging the basic immunology with clinical application.

After a very long and windy road, in December of 2005 the FDA approved CTLA4Ig for the treatment of rheumatoid arthritis. Orencia is the first-in-class antagonist of CD28 costimulation. In this perspective, we discuss the science that led to CTLA4Ig development and the clinical challenges in bringing the drug from the bench to the bedside.

Abatacept↗
PubMed2006

New therapeutics in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic disorder characterized predominately by a chronic inflammatory polyarthritis, with frequent progression to joint destruction and disability. Radiographic joint damage develops in as many as 75% of patients within the first 2 years of disease. For this reason, current RA treatment approaches have focused on early intensive therapy with multiple disease-modifying antirheumatic drugs. The approval of new drugs for this indication has expanded the number of therapeutic options that can potentially allow for tight control of the inflammatory process.

Antirheumatic Agents↗
PubMed2006

Serum, urinary, and salivary nitric oxide in rheumatoid arthritis: complexities of interpreting nitric oxide measures.

Nitric oxide (NO) may play important roles in rheumatoid arthritis (RA). RA is an inflammatory disease involving joints and other systems including salivary glands. To assess NO production in RA patients, we compared levels of serum, urine, and salivary nitrite and nitrate (NOx) in patients with RA and normal subjects, and we examined the relationships of these measures to disease activity. Serum, urine, and NOx levels as well as renal creatinine, NOx clearance and fractional excretion rates were compared in 25 RA patients and 20 age- and gender-matched healthy controls. Subjects were hospitalized for 3 days and placed on a NOx restricted diet. NOx was assayed using nitrate reductase and the Griess reagent. RA activity was assessed using standard clinical and laboratory measures. While consuming a restricted diet for 3 days to eliminate the effects of oral intake of NOx, 24 hour urinary NOx excretion decreased in both RA patients and healthy controls. Urine NOx levels at all time points were not significantly different between RA patients and normal subjects. Serum NOx levels also decreased during the 3 days of NOx restriction, but RA patients had higher serum NOx levels at all time points compared with the control group. Likewise, serum NOx/creatinine ratios were higher in RA patients than in controls. Although basal salivary flow rate and tear flow were lower in RA patients, salivary NOx levels did not differ between normal and RA subjects. While renal creatinine clearance was not different between the two groups, we found that RA patients had lower renal NOx clearance and lower renal NOx fractional excretion. After correction of p values for multiple comparisons, there were no significant relationships for the RA group between measures of disease activity and the urinary NOx, serum NOx, or urinary NOx clearance. Despite interest in the use of NO as a marker of disease activity, alterations in renal NOx clearance and fractional excretion in RA make it difficult to assess in vivo NO production even with strict dietary restriction of NOx intake.

Arthritis, Rheumatoid↗
PubMed2005

Cardiolipin polyspecific autoreactivity in two broadly neutralizing HIV-1 antibodies.

The design of a human immunodeficiency virus-1 (HIV-1) immunogen that can induce broadly reactive neutralizing antibodies is a major goal of HIV-1 vaccine development. Although rare human monoclonal antibodies (mAbs) exist that broadly neutralize HIV-1, HIV-1 envelope immunogens do not induce these antibody specificities. Here we demonstrate that the two most broadly reactive HIV-1 envelope gp41 human mAbs, 2F5 and 4E10, are polyspecific autoantibodies reactive with the phospholipid cardiolipin. Thus, current HIV-1 vaccines may not induce these types of antibodies because of autoantigen mimicry of the conserved membrane-proximal epitopes of the virus. These results may have important implications for generating effective neutralizing antibody responses by using HIV-1 vaccines.

AIDS Vaccines↗
PubMed2005

Brief communication: high incidence of venous thrombotic events among patients with Wegener granulomatosis: the Wegener's Clinical Occurrence of Thrombosis (WeCLOT) Study.

BACKGROUND: Venous thrombotic events (VTEs) have been observed in Wegener granulomatosis, but the incidence rate is not known. OBJECTIVE: To measure the incidence of VTEs in patients with Wegener granulomatosis. DESIGN: Prospective, observational cohort study. SETTING: A multicenter, randomized, double-blind, placebo-controlled treatment trial for Wegener granulomatosis. PATIENTS: 180 patients with Wegener granulomatosis enrolled during periods of active disease. MEASUREMENTS: Venous thrombotic events (deep venous thromboses or pulmonary emboli) were documented and confirmed prospectively. Incidence rates were calculated on the basis of time to first VTE. RESULTS: Thirteen patients had VTEs before enrollment. During 228 person-years of prospective follow-up, 16 VTEs occurred in 167 patients with no history of VTE. Median time from enrollment to VTE for patients with an event was 2.1 months. The incidence of VTE among patients with Wegener granulomatosis was 7.0 per 100 person-years (95% CI, 4.0 to 11.4). LIMITATIONS: Although prospectively recorded, screening for VTEs did not occur. CONCLUSIONS: The incidence rate of VTEs in Wegener granulomatosis is high when compared with available rates in the general population, patients with lupus, and patients with rheumatoid arthritis. These results have important implications for clinical care of patients with Wegener granulomatosis.

Double-Blind Method↗
PubMed2005

A serum proteomic approach to gauging the state of remission in Wegener's granulomatosis.

OBJECTIVE: To identify serum ion patterns that distinguish remission from active disease in patients with Wegener's granulomatosis (WG). METHODS: Using sera collected in the WG Etanercept Trial, we selected samples from patients who either were undergoing a period of extended disease remission or had recent flares of active WG. Unfractionated samples were randomized into sets for training and testing, such that remission sera and active disease sera could be analyzed without batch bias. Molecular species within the sera were ionized by high-resolution, matrix-assisted laser desorption ionization time-of-flight mass spectrometry. We then used a bioinformatics pattern-recognition tool to identify optimal combinations of ions. During the training stage, the clinical data (remission versus active disease) were provided in association with the spectral data from each sample. In the testing stage, we performed blinded testing on a previously unexamined set of samples. RESULTS: The most robust model, trained on a total of 82 samples (42 remission, 40 active disease), included 7 key ions with mass:charge ratios of 803.239, 2,171.672, 2,790.574, 3,085.237, 5,051.726, 5,833.989, and 6,630.465. The combined relative amplitudes of these 7 ions identified 5 distinct clusters of either remission or active disease samples during the training stage. In the testing stage, this model segregated 72 samples into the same 5 clusters, including 1 large remission cluster (n = 28) and another large active disease cluster (n = 32). Three smaller clusters of active disease or remission samples were also identified, with remission clusters populated by 2 samples in one cluster and 8 in another, and an active disease cluster populated by 2 samples. The model categorized 35 of 37 remission samples correctly (sensitivity 95%, 95% confidence interval [95% CI] 82.1-99.4) and 32 of 35 active disease samples correctly (specificity 91%, 95% CI 78.1-98.1). CONCLUSION: This serum proteomic profiling approach appears to be useful in distinguishing between states of stable clinical remission and active disease. Further validation and refinement of this strategy may help clinicians apply immunosuppressive therapies more judiciously among their patients, thereby avoiding morbidity and mortality from excessive treatment. Identification of the most robust and clinically useful combinations of ions will permit the rational selection of molecules for sequencing and analysis.

Antirheumatic Agents↗
PubMed2005

Damage caused by Wegener's granulomatosis and its treatment: prospective data from the Wegener's Granulomatosis Etanercept Trial (WGET).

OBJECTIVE: To analyze damage occurring in patients with Wegener's granulomatosis (WG) enrolled in the WG Etanercept Trial (WGET) and to correlate that damage with disease activity, adverse events, and quality of life. METHODS: The Vasculitis Damage Index (VDI) was applied to all 180 patients at trial entry and every 6 months throughout the trial. Items of damage were analyzed by presumed etiology (i.e., secondary to WG, to therapy, or both) and time of occurrence. Spearman's rank correlation coefficients were calculated between VDI scores and the Birmingham Vasculitis Activity Score for WG (BVAS/WG), frequency of flares, number of adverse events, and the patients' quality-of-life assessments. RESULTS: The mean VDI score was 1.3 at the study enrollment and 1.8 at the end of the trial. This increase was due to damage that occurred despite (or because of) therapy, including visual impairment, hearing loss, nasal blockade, pulmonary fibrosis, hypertension, renal insufficiency, peripheral neuropathy, gonadal failure, and diabetes mellitus. Only 11% of the enrolled patients had not sustained a single VDI item after 1 year of enrollment. When adjusted for baseline VDI, the baseline BVAS/WG correlated moderately well with the VDI score at 1 year (r = 0.20, P = 0.015). Increases in adjusted VDI scores also correlated with the number of adverse events, particularly among patients with limited WG (P = 0.06). CONCLUSION: Damage from both active disease and its treatment remain important problems for patients with WG. Despite the dramatic improvements in patient survival achieved over the last several decades, only a few patients with WG emerge from a period of active disease without sustaining some damage from the disease itself, its treatment, or both. An important measure of future therapeutic approaches will be their ability to reduce the damage accrued over time.

Double-Blind Method↗
PubMed2005

Herpes zoster in immunocompromised patients: incidence, timing, and risk factors.

PURPOSE: To evaluate the risk factors for herpes zoster as well as the incidence and timing of this complication in patients who were treated with immunosuppression because of active Wegener's granulomatosis. SUBJECTS AND METHODS: We studied the 180 Wegener's granulomatosis patients in the Wegener's Granulomatosis Etanercept Trial (WGET). Herpes zoster events during WGET were documented prospectively. Follow-up questionnaires were employed to describe the location, treatment, and complication(s) of herpes zoster and its therapy. Univariate and multivariate analyses were performed to evaluate risk factors, including history of herpes zoster, for the occurrence of herpes zoster during the trial. All analyses were based on the time to first occurrence of herpes zoster. RESULTS: Eighteen patients (10% of the WGET cohort) suffered a total of 19 herpes zoster episodes over a mean follow-up period of 27 months. The annual incidence of herpes zoster in the WGET cohort was 45 cases/1000 patient-years (95% confidence interval [CI]: 27, 70). The median time from enrollment to the occurrence of herpes zoster in the subgroup of patients with that complication was 16.5 months (+/- 9.4). Fifteen of the 19 herpes zoster events (79%) occurred between months 6 and 36, many months after the period of most intensive immunosuppression. In univariate analyses, history of serum creatinine > or =1.5 mg/dL before enrollment was associated with a relative risk (RR) of 3.0 (95% CI: 1.1, 7.8) for herpes zoster during WGET (P=.03). In multivariate analyses, serum creatinine > or =1.5 mg/dL was associated with an RR of 6.3 (95% CI: 2.0, 19.8; P=.002), and female sex with an RR of 4.6 (95% CI: 1.6, 13.2; P=.004). CONCLUSION: Renal dysfunction and female sex were consistently strong risk factors for herpes zoster events in this population. Contrary to expectation, most herpes zoster events did not occur during periods of most intensive immunosuppression. These data may inform studies of interventions designed to prevent herpes zoster in patients on treatment for immune-mediated diseases.

Adolescent↗
PubMed2005

Infliximab for the treatment of early rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic, chronic inflammatory disease characterised predominately by polyarthritis with frequent progression to permanent joint damage and disability. Evidence shows that starting treatment with disease-modifying antirheumatic drug (DMARD) therapy early in the course of disease can slow radiographic progression of RA compared with a more delayed approach. Moreover, in the early stages of RA, treatment with a combination of methotrexate (MTX), a traditional DMARD, and a biologic with tumour necrosis factor (TNF)-alpha blocking activity has proven to be more effective than using MTX alone. Among the approved TNF-alpha inhibitors, infliximab is a chimeric monoclonal antibody with high affinity and specificity for its target cytokine. It binds to soluble TNF monomers and trimers, as well as membrane-bound TNF-alpha, forming a stable complex which prevents TNF-alpha from binding to its receptor and triggering a biological response. The combination of MTX and infliximab therapy has shown superior clinical outcomes compared with MTX monotherapy in early RA, as well as greater protection against joint damage and physical disability. Although infliximab therapy has been associated with side effects, including serious infections, this drug can be administered with an acceptable margin of safety for several years by appropriate selection of patients, screening for latent and active tuberculosis, and monitoring of patients for infection and other toxicities. The knowledge of the benefits of infliximab therapy for early RA affords groundwork for developing more effective treatment strategies that can minimise disease progression over the long term.

Antibodies, Monoclonal↗
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

Combination of infliximab and methotrexate therapy for early rheumatoid arthritis: a randomized, controlled trial.

OBJECTIVE: To compare the benefits of initiating treatment with methotrexate (MTX) and infliximab (anti-tumor necrosis factor alpha [anti-TNFalpha] monoclonal antibody) with those of MTX treatment alone in patients with rheumatoid arthritis (RA) of < or =3 years' duration. METHODS: RA patients were eligible if they had active disease and no prior treatment with MTX or a TNFalpha inhibitor. One thousand forty-nine patients were randomly assigned in a 4:5:5 ratio to 3 treatment groups: MTX-placebo, MTX-3 mg/kg infliximab, and MTX-6 mg/kg infliximab. MTX dosages were rapidly escalated to 20 mg/week, and infliximab or placebo infusions were given at weeks 0, 2, and 6, and every 8 weeks thereafter through week 46. RESULTS: At week 54, the median percentage of American College of Rheumatology improvement (ACR-N) was higher for the MTX-3 mg/kg infliximab and MTX-6 mg/kg infliximab groups than for the MTX-placebo group (38.9% and 46.7% versus 26.4%, respectively; P < 0.001 for both comparisons). Patients in the MTX-3 mg/kg infliximab and MTX-6 mg/kg infliximab groups also showed less radiographic progression than those receiving MTX alone (mean +/- SD changes in van der Heijde modification of the total Sharp score at week 54: 0.4 +/- 5.8 and 0.5 +/- 5.6 versus 3.7 +/- 9.6, respectively; P < 0.001 for each comparison). In addition, physical function improved significantly more in the MTX-3 mg/kg infliximab and MTX-6 mg/kg infliximab groups than in the MTX-placebo group. Infliximab therapy was associated with a significantly higher incidence of serious infections, especially pneumonia. CONCLUSION: For patients with active RA in its early stages, combination therapy with MTX and infliximab provides greater clinical, radiographic, and functional benefits than treatment with MTX alone.

Adult↗
PubMed2004

N-acetyl transferase genotypes in relation to risk of developing systemic lupus erythematosus.

OBJECTIVE: To examine the association between N-acetyl transferase (NAT) genotype (NAT1 and NAT2) and risk of developing systemic lupus erythematosus (SLE). METHODS: DNA samples were collected from 243 recently diagnosed cases and 298 controls enrolled in a population based case-control study conducted in 60 counties in North Carolina and South Carolina, USA. RESULTS: There was no association between SLE and NAT1 genotype (OR 0.96, 95% CI 0.65, 1.4 for the presence of a *10 allele) or NAT2 genotype (OR 1.1, 95% CI 0.73, 1.6 for the slow- compared with fast-acetylation genotype). We saw some evidence of interaction between NAT genotypes and use of hair dyes (a source of arylamines), with higher risk seen among hair dye users who had both the *10 NAT1 allele and the NAT2 slow-acetylation genotype (OR 2.9, 95% CI 1.2, 6.9 in this subgroup compared with all others). CONCLUSION: Our results suggest that although there is little overall association between NAT genotypes and risk of developing SLE, the interaction between NAT1 and NAT2 and specific exposures such as hair dyes may be important. This finding highlights the need to consider exposure when assessing genetic susceptibility.

Adult↗