Tailored disorder in calcite organization in tergite cuticle of the supralittoral isopod Tylos europaeus Arcangeli, 1938.

The crustacean cuticle forms skeletal elements consisting of chitin-protein fibrils reinforced by amorphous and crystalline calcium carbonate and phosphate minerals. The edges of skeletal elements are of particular interest. They are subject to repeated strain and stress because they form transitions to the arthrodial membranes connecting them. These allow for relative movements of skeletal elements. In this study, we investigate structure, chemical composition, mineral organization and local mechanical properties of the anterior and posterior edges of the tergite cuticle in the conglobating beach isopod Tylos europaeus and compare these with the protective dorsal region of the tergites. The distribution of mineral phases at the edges resembles that of dorsal regions of the tergites. At the transition with the unmineralized arthrodial membrane the calcite containing distal exocuticle is replaced by epicuticular material and the subjacent cuticular layers containing amorphous calcium carbonate become enriched with amorphous calcium phosphate. At the edges, the local elastic modulus and hardness values are significantly lower compared to dorsal regions of the tergite cuticle, for both, the calcite and the amorphous mineral containing layers. The calcite within the tergite cuticle is assembled in different texture patterns: (i) almost random co-orientation, (ii) almost single crystalline calcite, and (iii) a graded organization. Calcite organization and co-orientation strength is highly variable, not only on very few tens of micrometres, but also between regions with different skeletal functionality. Our results show that besides structure and composition, patterns of calcite organization contribute to the hierarchical architecture and functionality of biological composites.

Functional adaptation of crustacean exoskeletal elements through structural and compositional diversity: a combined experimental and theoretical study.

The crustacean cuticle is a composite material that covers the whole animal and forms the continuous exoskeleton. Nano-fibers composed of chitin and protein molecules form most of the organic matrix of the cuticle that, at the macroscale, is organized in up to eight hierarchical levels. At least two of them, the exo- and endocuticle, contain a mineral phase of mainly Mg-calcite, amorphous calcium carbonate and phosphate. The high number of hierarchical levels and the compositional diversity provide a high degree of freedom for varying the physical, in particular mechanical, properties of the material. This makes the cuticle a versatile material ideally suited to form a variety of skeletal elements that are adapted to different functions and the eco-physiological strains of individual species. This review presents our recent analytical, experimental and theoretical studies on the cuticle, summarising at which hierarchical levels structure and composition are modified to achieve the required physical properties. We describe our multi-scale hierarchical modeling approach based on the results from these studies, aiming at systematically predicting the structure-composition-property relations of cuticle composites from the molecular level to the macro-scale. This modeling approach provides a tool to facilitate the development of optimized biomimetic materials within a knowledge-based design approach.

Electron microscopic and preparative methods for the analysis of isopod cuticle.

The crustacean cuticle consists of a complex organic matrix and a mineral phase. The physical and chemical properties of the cuticle are corellated to the specific functions of cuticular elements, leading to a large variety in its structure and composition. Investigation of the structure-function relationship in crustacean cuticle requires sophisticated methodological tools for the analysis of different aspects of the cuticular architecture. In the present paper we report improved preparation methods that, in combination with various electron microscopic techniques, have led to new insights of cuticle structure and composition in the tergite cuticle of Porcellio scaber. We used thin sections of non-decalcified tergites and decalcified resin embedded material for transmission electron microscopy and scanning transmission electron microscopy. Etched sagittal planes of bulk tergite samples were analysed with field emission scanning electron microscopy. We have found a distinct distal region within the exocuticle that differs from the subjacent proximal exocuticle in the arrangement of fibres. Within this distal exocuticle chitin-protein fibrils assemble to fibres with diameters between 15 and 50 nm that are embedded in a mineral matrix. In the proximal exocuticle and the endocuticle fibrils do not assemble to fibres and are surrounded by mineral individually. Furthermore, we show that the pore canals are filled with mineral, and demonstrate that mild etching of polished sagittal cuticle surfaces reveals regions containing mineral of diverse solubility.

Adolescent onset of lupus results in more aggressive disease and worse outcomes: results of a nested matched case-control study within LUMINA, a multiethnic US cohort (LUMINA LVII).

The objective of this study is to examine the clinical features and outcomes of patients with systemic lupus erythematosus (SLE) whose disease began in adolescence [juvenile-onset SLE (jSLE)] compared with adult-onset patients [adult-onset SLE (aSLE)] from a large multiethnic cohort. Systemic lupus erythematosus patients of African-American, Caucasian, or Hispanic ethnicity and >or=1 year follow-up were studied in two groups: jSLE (diagnosed at

Systemic lupus erythematosus in a multiethnic US Cohort LUMINA XLVIII: factors predictive of pulmonary damage.

The objective of this study was to determine the factors predictive of time to the occurrence of pulmonary damage in systemic lupus erythematosus (SLE). Six-hundred and twenty-six SLE patients from a multiethnic (Hispanics, African Americans and Caucasians) longitudinal study of outcome were studied. Pulmonary damage was defined as per the Systemic Lupus International Collaborating Clinics Damage Index. Socioeconomic-demographic, clinical, genetic, serological features, pharmacologic treatments, behavioural, psychological and disease activity [as per the Systemic Lupus Activity Measure-Revised (SLAM-R)] were examined. Factors associated with time to the occurrence of pulmonary damage were examined by Cox proportional hazards regressions. A Kaplan-Meier survival curve was also examined. Forty-six (7.3%) patients had pulmonary damage after a mean (SD) total disease duration of 5.3 (3.6) years. Among those patients, 25 had pulmonary fibrosis, 12 pulmonary hypertension, eight pleural fibrosis, four pulmonary infarction and four shrinking lung syndrome. Seven patients had more than one type of lung damage. Cumulative rates of pulmonary damage at five and 10 years were 7.6% and 11.6%, respectively. In the multivariable analyses, age (HR = 1.033, 95% CI 1.006-1.060; P = 0.0170), pneumonitis (HR = 2.307, 95% CI 1.123-4.739; P = 0.0229) and anti-RNP antibodies (HR = 2.344, 95% CI 1.190-4.618; P = 0.0138) were associated with a shorter time to the occurrence of pulmonary damage while photosensitivity (HR = 0.388, 95% CI 0.184-0.818; P = 0.0128) and oral ulcers (HR = 0.466, 95% CI 0.230-0.942; P = 0.0335) with a longer time. Pulmonary damage is relatively common in SLE. Age, pneumonitis and anti-RNP antibodies were associated with a shorter time to the development of permanent lung disease.

Systemic lupus erythematosus in a multiethnic US cohort LUMINA LI: anaemia as a predictor of disease activity and damage accrual.

OBJECTIVE: To examine if anaemia (and its severity) is associated with disease activity and damage accrual in systemic lupus erythematosus (SLE). METHODS: Four thousand four-hundred study visits in 613 SLE patients enrolled in LUMINA were studied. Anaemia was expressed in four categories of haematocrit (Hct) as defined by the Systemic Lupus Activity Measure-Revised (SLAM-R): no anaemia (Hct >35%), mild (Hct = 30-35%), moderate (Hct = 25-29%) and severe (Hct <25%). Anti-dsDNA antibodies were measured at baseline. Disease activity was assessed with the SLAM-R and damage with the Systemic Lupus International Collaborating Clinics Damage Index (SDI). The relationship between anaemia and anti-dsDNA antibodies with the SLAM and SDI scores was examined by univariate (one-way ANOVA) and multivariate (generalized linear models and generalized estimating equation regression) analyses. RESULTS: All categories of anaemia and anti-ds DNA were significantly associated with the SLAM-R at baseline and over time. However, only moderate and severe anaemia were associated with the SDI at baseline and over time, while the presence of anti-ds DNA was only associated with the SDI over time but not at baseline. Several clinical domains of the SLAM-R and SDI were associated with anaemia at baseline and over time. CONCLUSIONS: Mild, moderate and marked anaemia are strongly associated with disease activity in SLE. Moderate and marked anaemia are associated with damage accrual. These associations are observed both early and during the course of SLE. Different levels of anaemia could be used to monitor disease activity and predict organ/system damage in SLE.

Acute granulomatous lupus pneumonitis: the first case report.

Acute lupus pneumonitis is a rare form of pulmonary involvement in systemic lupus erythematosus (SLE). We present herein a patient with acute lupus pneumonitis who presented with acute onset of fever, cough, dyspnea and a miliary pattern on chest radiographs and computer tomography. Lung histopathology revealed bronchocentric granulomatosis. To our knowledge, this is the first documented case of granulomas in lung parenchyma believed to be caused by SLE. The differential diagnoses of acute lupus pneumonitis and the pertinent literature are discussed.

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.

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

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.

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.

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.

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.

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.

Relationship between adherence to study and clinic visits in systemic lupus erythematosus patients: data from the LUMINA cohort.

The aim of this study was to examine the relationship between nonadherence with study visits and with regularly scheduled clinic visits after adjusting for other patient and disease characteristics. One hundred and forty-one LUMINA patients with appointment data in the institutions' computerized systems (UAB and UTH) were studied. 'No shows' were assessed as the percentage of appointments not attended for either rheumatology, other clinics and LUMINA visits (from zero to 100%). Eighty-nine percent of the patients were women, 40% were Caucasians, 55% African-Americans and 5% Hispanics. 'No shows' to rheumatology were associated with non-Caucasian ethnicity, younger age, single marital status, lack of home ownership, 'no shows' to other clinics and to the LUMINA study, greater disease activity and to some disease manifestations (serositis, renal involvement, positive anti-dsDNA antibodies). In multivariable analyses, features predictive of rheumatology 'no shows' were lack of home ownership, 'no shows' to LUMINA study visits, renal involvement and serosal manifestations. Nonadherence with study visits and with regularly scheduled care at rheumatology clinics were associated. Other factors predictive of nonadherence to recommended care were lack of home ownership (a measurement of low socioeconomic status) and the presence of disease manifestations (i.e., renal or serosal involvement). These data should be considered when caring for patients with SLE.

Early clinical manifestations, disease activity and damage of systemic lupus erythematosus among two distinct US Hispanic subpopulations.

OBJECTIVES: To compare the baseline clinical manifestations, immunological features, disease activity and damage accrual in systemic lupus erythematosus (SLE) patients from two US Hispanic subgroups. METHODS: A total of 105 Hispanic SLE patients from Texas (a population of Mexican or Central American ancestry) and 81 from the island of Puerto Rico (all Puerto Ricans) participating in a longitudinal study of outcome were examined. The socio-economic/demographic, clinical and immunological variables were obtained at the time of enrollment (T(0)). Disease activity was determined with the Systemic Lupus Activity Measure (SLAM), and disease damage with the Systemic Lupus International Collaborating Clinics (SLICC) Damage Index (SDI). Disease activity was also determined at the time of diagnosis (T(D)). RESULTS: At T(0) Hispanics from Texas were younger than those from Puerto Rico (33.1 +/- 12.0 vs 37.5 +/- 11.6 yr, P = 0.0125). Both groups were similar with regard to gender distribution (92.4 vs 95.1% females) and disease duration (1.4 +/- 1.4 vs 1.7 +/- 1.3 yr). Hispanics from Texas were more likely to have serositis (60.0 vs 8.6%, P < 0.0001), renal involvement (41.0 vs 13.6%, P < 0.0001), psychosis (5.7 vs 0.0%, P = 0.0365) and thrombocytopenia (21.0 vs 3.7%, P = 0.0006). On the other hand, Hispanics from Puerto Rico were more likely to have photosensitivity (81.5 vs 41.0%, P < 0.0001), malar rash (65.4 vs 45.7%, P = 0.0074) and discoid rash (13.6 vs 2.9%, P = 0.0060). At baseline, the presence of anti-dsDNA antibodies was higher in Hispanics from Texas (69.5% vs 46.9%, P = 0.0018) while anti-Ro antibodies were more frequent in Hispanics from Puerto Rico (24.7 vs 11.4%, P = 0.0175). Mean SLAM scores at T(D) (12.9 +/- 6.4 vs 9.1 +/- 4.6, P < 0.0001) and T(0) (10.9 +/- 6.3 vs 6.6 +/- 3.8, P < 0.0001) were significantly higher in Hispanics from Texas. Similarly, mean SDI scores at T(0) were higher in Hispanics from Texas (0.67 +/- 1.08 vs 0.26 +/- 0.54, P = 0.0026). By stepwise Poisson regression, SDI scores were associated with older age, disease activity and ethnicity (Hispanics from Texas). CONCLUSIONS: Early in SLE, marked differences are observed between Hispanics from Texas and Puerto Rico. Higher disease activity, more major organ involvement, higher frequency of anti-dsDNA antibodies and more damage accrual occur in Hispanic lupus patients from Texas than in those from Puerto Rico.

Systemic lupus erythematosus in three ethnic groups. XX. Damage as a predictor of further damage.

OBJECTIVE: To examine the predictors of damage in a multiethnic cohort of systemic lupus erythematosus (SLE) patients with a specific focus on damage at baseline. PATIENTS AND METHODS: SLE patients from a multiethnic US (Hispanic, African-American and Caucasian) cohort (LUMINA: Lupus in Minority populations, Nature versus nurture) were included if they had > or =6 months of follow-up in the cohort. Damage was measured with the Systemic Lupus International Collaborating Clinics (SLICC) Damage Index (SDI). The dependent variable was the change in SDI score between study visits. Predictors were from the preceding visit. Variables known to affect damage accrual in SLE were included in the analyses. RESULTS: Three hundred and fifty-two patients (82 Hispanics, 153 African-Americans and 117 Caucasians) representing 1795 patient visits were included. Previous damage was found to be a significant predictor of subsequent damage accrual (P < 0.0001). Other variables predictive of subsequent damage accrual were disease activity (P < 0.0001), older age (P = 0.041) and use of corticosteroids (P = 0.0048). CONCLUSIONS: Once damage occurs in SLE, further damage is expected to occur. This is more likely to be the case if disease activity persists. These data have clinical implications for the management of SLE patients.

Systemic lupus erythematosus in three ethnic groups: XV. Prevalence and correlates of fibromyalgia.

The purpose of this study was to determine the prevalence and correlates of fibromyalgia (FM) in a prospective, multiethnic systemic lupus (SLE) cohort. A total of 266 SLE patients with disease duration of < or = 5 years at study entry were evaluated longitudinally for the presence of FM (per ACR criteria). Sociodemographic factors, behavioral/psychological variables, clinical features, serologic factors (autoantibodies), and self-reported functioning (MOS SF-36) were ascertained in all patients. Subjects were evaluated at study entry and annually thereafter. The prevalence of FM was then calculated, as was the prevalence of FM-like manifestations (widespread pain with at least 6, but fewer than 11/18 tender points). Variables were evaluated for association with FM or FM-like manifestations by univariate and stepwise logistic regression analyses. FM was present in 14 patients (5%; 9/92 Caucasians (C), 4/109 African Americans (AA), 1/65 Hispanics (H)) and FM/FM-like manifestations in 35 (13%; 16 C, 9 AA, 10 H). There was no difference noted between those with and without FM with respect to gender, education level, income below poverty level, disease activity or damage. By stepwise logistic regression analyses, the strongest association with both FM and FM/FM-like manifestations was a self-reported history of anxiety or affective disorder (P = 0.0237, OR = 4.6 and P = 0.0068, OR = 3.4, respectively). Caucasian ethnicity was strongly associated with FM (P = 0.0066, OR = 7.5) and African American ethnicity was negatively associated with FM/FM-like (P = 0.0204, OR = 0.3). Poorer self-reported physical functioning was associated with FM/FM-like (P = 0.0443, OR = 0.96). FM and FM-like manifestations correlate best with the presence of Caucasian ethnicity, concomitant anxiety or affective disorder, and to a lesser extent with poorer self-reported physical functioning. African American ethnicity is negatively associated with the combination of FM and FM-like manifestations. Clinical measures of disease activity, disease damage, specific organ dysfunction, sociodemographic factors and serologic features are not correlated with FM in this early SLE cohort.