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G S Alarcón

Publications and source records attributed to G S Alarcón.

At least 19 recordsLinked to original sources
PubMed2007

Neuropsychiatric events at the time of diagnosis of systemic lupus erythematosus: an international inception cohort study.

OBJECTIVE: To describe the prevalence, characteristics, attribution, and clinical significance of neuropsychiatric (NP) events in an international inception cohort of systemic lupus erythematosus (SLE) patients. METHODS: The study was conducted by the Systemic Lupus International Collaborating Clinics (SLICC). Patients were enrolled within 15 months of fulfilling the American College of Rheumatology (ACR) SLE classification criteria. All NP events within a predefined enrollment window were identified using the ACR case definitions of 19 NP syndromes. Decision rules were derived to determine the proportion of NP disease attributable to SLE. Clinical significance was determined using the Short Form 36 (SF-36) Health Survey and the SLICC/ACR Damage Index (SDI). RESULTS: A total of 572 patients (88% female) were recruited, with a mean +/- SD age of 35 +/- 14 years. The mean +/- SD disease duration was 5.2 +/- 4.2 months. Within the enrollment window, 158 of 572 patients (28%) had at least 1 NP event. In total, there were 242 NP events that encompassed 15 of 19 NP syndromes. The proportion of NP events attributed to SLE varied from 19% to 38% using alternate attribution models and occurred in 6.1-11.7% of patients. Those with NP events, regardless of attribution, had lower scores on the SF-36 and higher SDI scores compared with patients with no NP events. CONCLUSION: Twenty-eight percent of SLE patients experienced at least 1 NP event around the time of diagnosis of SLE, of which only a minority were attributed to SLE. Regardless of attribution, the occurrence of NP events was associated with reduced quality of life and increased organ damage.

Adult↗
PubMed2006

Systemic lupus erythematosus in a multiethnic US cohort (LUMINA) XL II: factors predictive of new or worsening proteinuria.

OBJECTIVES: To determine the factors predictive of new or worsening proteinuria in a large multiethnic cohort of patients with systemic lupus erythematosus (SLE). METHODS: Five hundred and twenty-nine SLE patients from a multiethnic US cohort [LUpus in MInorities: NAture versus Nurture (LUMINA)] were evaluated for new or worsening proteinuria using the categories of the Systemic Lupus Activity Measure-Revised: (1), normal; (2), trace or 1+ proteinuria on the dipstick; (3), 2-3+ proteinuria and (4), > or =4+ proteinuria. A rise in urinary protein was considered a positive event visit. Basic demographic and socioeconomic variables were assessed at baseline (T0). Clinical and immunological variables including disease features, activity, duration, comorbidities (such as hypertension and diabetes), medications and autoantibodies were assessed at the visit preceding a positive event visit. Selected HLA-DR and HLA-DQ alleles, and FCGR receptor polymorphisms were assessed. Data were analysed using logistic regression analyses and generalized estimating equations. RESULTS: There were 243 patients (59.1% of 93 Texan Hispanics, 37.0% of 100 Puerto Rican Hispanics, 58.0% of 181 African Americans and 29.7% of 155 Caucasians) with new or worsening proteinuria, and 364 positive events in 2801 visits. Younger age [Odds ratio (OR) = 1.013, 95% confidence limits (CL) = 1.001-1.024, P < 0.0334], anti-dsDNA (OR = 1.554, CL = 1.149-2.100, P < 0.0042), and HLA-DRB1*1503 (OR = 1.746, 95% CL = 1.573-2.2673, P < 0.0103) were found to independently predict the occurrence of new or worsening proteinuria. CONCLUSION: The factors predictive of new or worsening proteinuria include traditional factors associated with lupus nephritis, such as age and anti-dsDNA, as well as HLA-DRB1*1503, which has not been previously described in association with lupus nephritis, new or worsening proteinuria.

Adult↗
PubMed2006

Predictors of post-partum damage accrual in systemic lupus erythematosus: data from LUMINA, a multiethnic US cohort (XXXVIII).

OBJECTIVE: To determine the impact of pregnancy on systemic lupus erythematosus (SLE) outcome. METHODS: SLE patients, age >or=16 yrs, disease duration <or=5 yrs at enrolment in LUMINA, a multiethnic cohort (Hispanics, African-Americans and Caucasians), were studied. The first pregnancy after SLE diagnosis was examined. A good pregnancy outcome was a full-term delivery; an adverse outcome was a miscarriage, abortion, premature birth or stillbirth. Dependent variables were disease activity (Systemic Lupus Activity Measure-Revised, SLAM-R) and damage accrual [Systemic Lupus International Collaborating Clinics (SLICC) Damage Index, SDI]. Differences in these variables between the visit immediately prior to, and the first visit after, pregnancy and their relationship with pregnancy outcome were examined. Damage accrual due to pregnancy exposure was examined by a case-crossover design. RESULTS: Sixty-three SLE women from all ethnic groups were included. The mean (S.D.) age and disease duration at pregnancy outcome were 27.6 (6.5) yrs and 18.3 (22.5) months, respectively. Adverse pregnancy outcomes occurred in 76.2% women. The SLAM-R and SDI scores were statistically different after pregnancy (P = 0.050 and P < 0.001, respectively); the SDI score was independent of pregnancy outcome but strongly associated with pregnancy duration (P = 0.006), disease activity (P = 0.001), damage prior to pregnancy (P < 0.001) and total disease duration (P = 0.039) by multivariable analyses. Exposure to pregnancy itself did not impact on damage accrual in the case-crossover analyses of 142 patients (17 pregnancy exposures) (OR = 1.25; 95% CI 0.336-4.655; P = 0.480). CONCLUSIONS: Pregnancy duration, total disease duration, disease activity and damage immediately prior to pregnancy decisively impact on damage accrual after pregnancy in patients with SLE.

Adult↗
PubMed2006

Systemic lupus erythematosus in a multiethnic US cohort LUMINA (XLI): factors predictive of self-reported work disability.

OBJECTIVE: To examine the risk factors for self-reported work disability in patients from the LUpus in MInorities: NAture vs. Nurture cohort with systemic lupus erythematosus (SLE). METHODS: Patients with SLE of Hispanic (Texas and Puerto Rico), African American and Caucasian ethnicity were studied. Work disability was defined by patients' self-report. Only patients known to be employed at the baseline visit were included. The probabilities of self-reporting work disability over time were examined by the Kaplan-Meier method; differences between ethnic groups were examined by the log-rank test. The relationship of baseline socioeconomic-demographic, clinical, behavioural and psychological features with work disability was examined by standard statistical tests. Variables with p<or=0.10 in these analyses were examined by logistic regression. RESULTS: The rate of self-reported work disability among the 273 patients studied was 19% at 5 years; it was numerically higher for the African Americans (25%) than for the Hispanics from Texas (19%) and the Caucasians (18%). The rate for the Hispanics from Puerto Rico was 7% at 2 years; 5-year rates could not be estimated for this ethnic subgroup (shorter follow-up in the cohort). In the regression analysis, age, male sex, poverty, total disease duration, disease activity and damage accrual were predictors of work disability. CONCLUSIONS: The rate of work disability was 19% at 5 years. Patients with SLE with more severe disease and with lower socioeconomic status are at high risk of becoming disabled. The toll SLE imposes could possibly be reduced in patients at risk if, in addition to medical treatment, services needed to overcome their disadvantageous socioeconomic status are provided.

Adult↗
PubMed2006

Racial or ethnic differences in allele frequencies of single-nucleotide polymorphisms in the methylenetetrahydrofolate reductase gene and their influence on response to methotrexate in rheumatoid arthritis.

BACKGROUND: The anti-folate drug methotrexate (MTX) is commonly used to treat rheumatoid arthritis. OBJECTIVE: To determine the allele frequencies of five common coding single-nucleotide polymorphisms (SNPs) in the methylenetetrahydrofolate reductase (MTHFR) gene in African-Americans and Caucasians with rheumatoid arthritis and controls to assess whether there are differences in allele frequencies among these ethnic or racial groups and whether these SNPs differentially affect the efficacy or toxicity of MTX. METHODS: Allele frequencies in the 677, 1298 and 3 additional SNPs in the MTHFR coding region in 223 (193 Caucasians and 30 African-Americans) patients with rheumatoid arthritis who previously participated in one of two prospective clinical trials were characterised, and genotypes were correlated with the efficacy and toxicity of MTX. Another 308 subjects with rheumatoid arthritis who participated in observational studies, one group predominantly Caucasian and the other African-American, as well as 103 normal controls (53 African-Americans and 50 Caucasians) were used to characterise allele frequencies of these SNPs and their associated haplotypes. RESULTS: Significantly different allele frequencies were seen in three of the five SNPs and haplotype frequencies between Caucasians and African-Americans. Allele frequencies were similar between patients with rheumatoid arthritis and controls of the same racial or ethnic group. Frequencies of the rs4846051C, 677T and 1298C alleles were 0.33, 0.11 and 0.13, respectively, among African-Americans with rheumatoid arthritis. Among Caucasians with rheumatoid arthritis, these allele frequencies were 0.08 (p<0.001 compared with African-Americans with rheumatoid arthritis), 0.30 (p = 0.002) and 0.34 (p<0.001), respectively. There was no association between SNP alleles or haplotypes and response to MTX as measured by the mean change in the 28-joint Disease Activity Score from baseline values. In Caucasians, the 1298 A (major) allele was associated with a significant increase in MTX-related adverse events characteristic of a recessive genetic effect (odds ratio 15.86, 95% confidence interval 1.51 to 167.01; p = 0.021), confirming previous reports. There was an association between scores of MTX toxicity and the rs4846051 C allele, and haplotypes containing this allele, in African-Americans, but not in Caucasians. CONCLUSIONS: : These results, although preliminary, highlight racial or ethnic differences in frequencies of common MTHFR SNPs. The MTHFR 1298 A and the rs4846051 C alleles were associated with MTX-related adverse events in Caucasians and African-Americans, respectively, but these findings should be replicated in larger studies. The rs4846051 SNP, which is far more common in African-Americans than in Caucasians, can also be proved to be a useful ancestry informative marker in future studies on genetic admixture.

Black or African American↗
PubMed2006

Systemic lupus erythematosus in a multiethnic cohort: LUMINA XXXV. Predictive factors of high disease activity over time.

AIM: To ascertain the predictive factors of high levels of disease activity in systemic lupus erythematosus (SLE). PATIENTS AND METHODS: Patients with SLE (American College of Radiology criteria), aged >or=16 years, with disease duration 10). A basic multivariable model (including age, sex, ethnicity, health insurance, social support, abnormal illness-related behaviours, helplessness and prior disease activity) was first examined. Additional models were built by including other variables. RESULTS: 554 patients (100 Hispanics from Texas, 94 Hispanics from Puerto Rico, 199 African Americans, 161 Caucasians) and 2366 visits were analysed; 47% of the patients and 29% of the visits met the definition of high disease activity (more common among African Americans (72.0%) and Hispanics from Texas (71.3%) than among Caucasians (43.9%) and Hispanics from Puerto Rico (31.9%)). Variables found to predict high levels of disease activity were Hispanic (from Texas) and African American ethnicities, lack of health insurance, helplessness, abnormal illness-related behaviours and poor social support; age was negatively associated with high levels of disease activity. African admixture and anti-double-stranded DNA antibodies also predicted high levels of disease activity, as did prior disease activity. None of the human leucocyte antigen variables were retained in the models. CONCLUSIONS: Socioeconomic-demographic (age, ethnicity, health insurance), behavioural and psychological variables are important mediators of high levels of disease activity in SLE during its course. Interventions aimed at modifiable factors may improve the outcomes of SLE.

Adolescent↗
PubMed2006

Systemic lupus erythematosus in a multiethnic U.S. cohort (LUMINA) XXVII: factors predictive of a decline to low levels of disease activity.

The objective of this study was to examine factors predictive of a decline to low levels of disease activity in a cohort of systemic lupus erythematosus (SLE) patients. Patients with SLE of Hispanic (from Texas or Puerto Rico), African-American or Caucasian ethnicity from a multiethnic cohort were included. A decline to low levels of disease activity was defined as a score < or =5 as per the Systemic Lupus Activity Measure-Revised (SLAM-R) at any annual study visit if preceded by a SLAM-R > or =8. Using Generalized Estimating Equation (GEE), socioeconomic-demographic, behavioral, function, psychological, laboratory and clinical data [disease manifestations, number of ACR criteria accrued at diagnosis and damage accrual as per the Systemic Lupus International Collaborating Clinics (SLICC) Damage Index (SDI)] from the visit preceding that meeting the definition were examined as predictors of decline to low levels of disease activity. Two-hundred and eighty-seven patients (67 Hispanics from Texas, 32 Hispanics form Puerto Rico, 120 African-Americans and 68 Caucasians), accounting for 632 visits were analyzed. In the GEE multivariable analysis, higher degrees of social support (OR = 1.208, 95% CI 1.059-1.379; P = 0.005) were predictive of a decline to low levels of disease activity, while the number of ACR criteria accrued at diagnosis (OR = 0.765, 95% CI 0.631-0.927; P = 0.006) and damage (OR = 0.850, 95% CI 0.743-0.972, P = 0.018) were negatively associated. These data suggest that a decline to low levels of disease activity in lupus patients seems to be multifactorial; this study also underscores the importance of social support for lupus patients.

Adult↗
PubMed2006

Systemic lupus erythematosus in a multiethnic U.S. cohort (LUMINA) XXXI: factors associated with patients being lost to follow-up.

The objective of this study was to determine the frequency of loss to follow-up and the factors predictive of its occurrence in a systemic lupus erythematosus (SLE) multiethnic cohort. We studied SLE patients from the LUMINA cohort (Hispanics from Texas and from the Island of Puerto Rico, African-Americans and Caucasians). Loss to follow-up was defined as subjects who failed to attend two or more of the latest consecutive yearly study visits. The relationship between baseline features and loss to follow-up was examined by univariable and multivariable Cox regression analyses with loss to follow-up as the dependent variable. The retention rate in the cohort was estimated by the Kaplan-Meier method. Five-hundred and fifty-four patients with a mean (SD) follow-up of 3.4 (2.9) years were studied. One-hundred and fifty-eight (29%) met the definition of lost to follow-up. The cumulative loss to follow-up rate at five years was 36%. The cumulative loss to follow-up rate at five years was higher for the African-Americans. Patients lost to follow-up tended to be younger and more likely to have poor social support and higher levels of helplessness. They also tended to have more renal involvement and more active disease as per the Systemic Lupus Activity Measure-Revised. Disease activity (hazard ratio = 1.04, 95% confidence interval 1.01-1.07, P = 0.02) was the only variable independently contributing to loss to follow-up. Our data suggest that in longitudinal SLE studies, loss to follow-up does not occur at random and it differs between ethnic groups and is also particularly higher among patients with more active disease. Pro-active measures may need to be applied to decrease the probability of patients 'at risk' of becoming lost to follow-up and to preserve the integrity of the cohort.

Adult↗
PubMed2006

Systemic lupus erythematosus in a multi-ethnic cohort (LUMINA) XXXII: [corrected] contributions of admixture and socioeconomic status to renal involvement.

Renal involvement in systemic lupus erythematosus (SLE) is more frequent in minorities. We examined whether genetic or socioeconomic status (SES) explain these disparities in a large multiethnic (Hispanics from Texas and Puerto Rico, African Americans and Caucasians) SLE cohort. Renal involvement was defined as WHO Class II-V and/or proteinuria (> 0.5 g/24 h or 3+) attributable to SLE and/or abnormal urinary sediment, proteinuria 2+, elevated serum creatinine/ decreased creatinine clearance twice, 6 months apart present any time over the course of the disease. Ancestry informative markers (AIMS) were used to define the admixture proportions in each patient and group. Logistic regression models were examined to determine the percentage variance (R2) in renal involvement related to ethnicity that is explained by socio-economic status (SES) and admixture (adjusting for age, gender and disease duration, basic model). Four-hundred and fifty-nine (out of 575) patients were included; renal involvement occurred in 44.6% Texas Hispanics, 11.3% Puerto Rico Hispanics, 45.8% African Americans, 18.3% Caucasians. SES accounted for 14.5% of the variance due to ethnicity (after adjusting for basic model variables), admixture 36.8% and both, 12.2%; 45.9% of the variance remained unexplained. Alternative models for decreased glomerula filtration rate and end-stage renal disease were comparable in the distribution of the explanatory variables. Our data indicate that genetic factors appear to be more important than SES in explaining the ethnic disparities in the occurrence of renal involvement.

Adult↗
PubMed2005

Systemic lupus erythematosus in a multiethnic US cohort (LUMINA): XXIV. Cytotoxic treatment is an additional risk factor for the development of symptomatic osteonecrosis in lupus patients: results of a nested matched case-control study.

BACKGROUND: Osteonecrosis is common in systemic lupus erythematosus (SLE) and often disabling. The role of glucocorticoids in its development is well known. OBJECTIVE: To explore other possible risk factors for osteonecrosis in SLE. METHODS: A nested matched case-control study undertaken in the context of a large, longitudinal, multiethnic lupus cohort (LUMINA), currently formed of 571 SLE patients meeting American College of Rheumatology criteria. All those developing symptomatic osteonecrosis after the diagnosis of SLE were considered cases. Two controls matched for age, disease duration, ethnicity, and centre were selected for each case. Cases and controls were compared by univariable analyses using selected variables. Variables with p<0.10 and those thought clinically relevant were entered into conditional logistic regression models including either the average dose or the highest dose of glucocorticoids, with osteonecrosis as the dependent variable. RESULTS: 32 cases were identified and 59 matched controls selected (in five cases only one control could be found). By univariable analyses, both groups were largely comparable for socioeconomic-demographic, clinical, and laboratory variables. Cases were less exposed to hydroxychloroquine (as assessed by the percentage of exposure time) (p = 0.026), used higher doses of glucocorticoids (average and highest doses) (p = 0.011 and 0.001, respectively), and received cytotoxic drugs more often (p = 0.015). In the multivariable analyses only cytotoxic drug use (both models) and the highest dose of glucocorticoids remained associated with the occurrence of osteonecrosis. CONCLUSIONS: Cytotoxic drug use is a risk factor for the development of symptomatic osteonecrosis in SLE patients, along with glucocorticoids. No definite protective factors were identified.

Adult↗
PubMed2005

Systemic lupus erythematosus in a multiethnic cohort (LUMINA): XXVIII. Factors predictive of thrombotic events.

OBJECTIVE: To determine the relationship between the presence of antiphospholipid (aPL) antibodies, hydroxychloroquine use and the occurrence of thrombotic events in patients with systemic lupus erythematosus (SLE). METHODS: Four hundred and forty-two SLE patients from the LUMINA (Lupus in Minorities: Nature vs Nurture) cohort, a multiethnic (Hispanics from Texas, n = 99 and Puerto Rico, n = 36; African Americans, n = 172; and Caucasians, n = 135) cohort, were studied by generalized estimating equation (GEE) to determine the relationship between antiphospholipid (aPL) antibodies (measured as IgG and IgM aPL antibodies and/or the lupus anticoagulant) at enrolment or historically prior to enrolment, hydroxychloroquine use (ever) and the occurrence of thrombotic (central and/or peripheral, arterial and/or venous) events after adjusting for known and possible confounders [socioeconomic-demographic features, smoking, disease activity and damage, serum cholesterol levels, anti-oxidized low-density lipoprotein IgG and IgM antibodies, and high-sensitivity (hs) C-reactive protein]. Postanalysis correlation between aPL and anticardiolipin (aCL) assays was attempted by performing aCL assays on random samples of patients whose aPL status was known. RESULTS: A number of clinical variables were significant in the univariable analyses; however, in the multivariable GEE analyses, only smoking [odds ratio (OR) 2.777, 95% confidence interval (CI) 1.317-5.852] and disease activity as measured by the SLAM (Systemic Lupus Activity Measure) (OR 1.099; 95% CI 1.053-1.147) were significant. In particular, hydroxychloroquine use, which appeared to be protective against thrombotic events in the univariable analyses, was not retained in the multivariable analyses. aPL antibodies were not significant in either analysis. Few additional aPL-positive patients emerged from the validation study. CONCLUSIONS: Smoking and disease activity emerged as important determinants in the occurrence of thrombotic events in our patients. Comprehensive treatment strategies should be directed to both smoking cessation and control of disease activity in patients with SLE.

Antibodies, Antiphospholipid↗
PubMed2005

Lack of recording of systemic lupus erythematosus in the death certificates of lupus patients.

OBJECTIVE: To determine to what extent the diagnosis of systemic lupus erythematosus (SLE) in deceased lupus patients is under-reported in death certificates, and the patient characteristics associated with such an occurrence. METHODS: The death certificates of 76 of the 81 deceased SLE patients from two US lupus cohorts (LUMINA for Lupus in Minorities: Nature vs Nurture and CLU for Carolina Lupus Study), including 570 and 265 patients, respectively, were obtained from the Offices of Vital Statistics of the states where the patients died (Alabama, Georgia, North Carolina, South Carolina, Tennessee and Texas). Both cohorts included patients with SLE as per the American College of Rheumatology criteria, aged > or =16 yr, and disease duration at enrolment of < or =5 yr. The median duration of follow-up in each cohort at the time of these analyses ranged from 38.1 to 53.0 months. Standard univariable analyses were performed comparing patients with SLE recorded anywhere in the death certificate and those without it. A multivariable logistic regression model was performed to identify the variables independently associated with not recording SLE in death certificates. RESULTS: In 30 (40%) death certificates, SLE was not recorded anywhere in the death certificate. In univariable analyses, older age was associated with lack of recording of SLE in death certificates [mean age (standard deviation) 50.9 (15.6) years and 39.1 (18.6) yr among those for whom SLE was omitted and included on the death certificates, respectively, P = 0.005]. Patients without health insurance, those dying of a cardiovascular event and those of Caucasian ethnicity were also more likely to be in the non-recorded group. In the multivariable analysis, variables independently associated with not recording SLE as cause of death were older age [odds ratio = (95% confidence interval) 1.043 (1.005-1.083 per yr increase); P = 0.023] and lack of health insurance [4.649 (1.152-18.768); P = 0.031]. CONCLUSIONS: A high proportion of SLE diagnoses are not recorded in death certificates. Older patients and those without health insurance are more prone to have SLE not recorded. These findings do have implications for the assessment of the impact of this disease in epidemiological studies conducted using vital statistics records.

Adolescent↗
PubMed2005

Systemic lupus erythematosus in a multiethnic US Cohort (LUMINA). XXX: association between C-reactive protein (CRP) gene polymorphisms and vascular events.

OBJECTIVES: To determine if a polymorphic GTn repeat in the intron of the C-reactive protein (CRP) gene associates with occurrence of vascular arterial events in systemic lupus erythematosus (SLE). METHODS: We performed a nested case-control study on the LUMINA cohort of 546 Hispanic, African-American and Caucasian SLE patients. Twenty-five patients who developed vascular arterial events (i.e. myocardial infarction, angina, coronary artery bypass graft surgery, stroke, claudication, gangrene or significant tissue loss and/or arterial peripheral thrombosis) after enrolment were selected as cases and 32 ethnically matched patients with no previous vascular arterial events served as controls. Their CRP gene GTn polymorphism and plasma CRP was determined. RESULTS: Patients with vascular events had more severe SLE and were more likely to have plasma CRP in the highest quintile of measured values. The overall distribution of GTn alleles for patients with vascular events had a greater number of the GT20 variant compared with controls [26.0% of alleles (13/50) vs 15.6% (10/64)]. This greater number of GT20 in patients with vascular events was observed for African-Americans [29.2% (7/24) vs 21.0% (8/38)] and Hispanics [33.0% (4/12) vs 0% (0/16)] but not for Caucasians [14.3% (2/14) vs 20.0% (2/10)]. For African-Americans and Hispanics combined (45 patients), the frequency of GT20 in those with vascular events (30.6%, 11/36) was significantly higher than in those without them (14.8%, 8/54) (P<0.05, one-tailed test for difference in proportions). When patients were categorized according to the number of GT20 alleles they carried (thus GT20/GT20, GT20/GTx or GTx/GTx, where x is any allele other than GT20), for both African-Americans and Hispanics the likelihood of vascular arterial events increased in proportion with the GT20 dose, and all GT20-homozygous patients developed vascular arterial events. CONCLUSIONS: The CRP GT20 variant is more likely to occur in African-American and Hispanic SLE patients than in Caucasian ones, and SLE patients carrying the GT20 allele are more likely to develop vascular arterial events.

Adult↗