Effects of general and central adiposity on circulating lipoprotein, lipid, and metabolite levels in UK Biobank: A multivariable Mendelian randomization study

Background

The direct effects of general adiposity (body mass index (BMI)) and central adiposity (waist-to-hip-ratio (WHR)) on circulating lipoproteins, lipids, and metabolites are unknown.

Methods

We used new metabolic data from UK Biobank (N=109,532, a five-fold higher N over previous studies). EDTA-plasma was used to quantify 249 traits with nuclear-magnetic-resonance spectroscopy including subclass-specific lipoprotein concentrations and lipid content, plus pre-glycemic and inflammatory metabolites. We used univariable and multivariable two-stage least-squares regression models with genetic risk scores for BMI and WHR as instruments to estimate total (unadjusted) and direct (mutually-adjusted) effects of BMI and WHR on metabolic traits; plus effects on statin use and interaction by sex, statin use, and age (proxy for medication use).

Findings

Higher BMI decreased apolipoprotein B and low-density lipoprotein cholesterol (LDL-C) before and after WHR-adjustment, whilst BMI increased triglycerides only before WHR-adjustment. These effects of WHR were larger and BMI-independent. Direct effects differed markedly by sex, e.g., triglycerides increased only with BMI among men, and only with WHR among women. Adiposity measures increased statin use and showed metabolic effects which differed by statin use and age. Among the youngest (38-53y, statins-5%), BMI and WHR (per-SD) increased LDL-C (total effects: 0.04-SD, 95%CI=-0.01,0.08 and 0.10-SD, 95%CI=0.02,0.17 respectively), but only WHR directly. Among the oldest (63-73y, statins-29%), BMI and WHR directly lowered LDL-C (-0.19-SD, 95%CI=-0.27,-0.11 and -0.05-SD, 95%CI=-0.16,0.06 respectively).

Interpretation

Excess adiposity likely raises atherogenic lipid and metabolite levels exclusively via adiposity stored centrally, particularly among women. Apparent effects of adiposity on lowering LDL-C are likely explained by an effect of adiposity on statin use.

Funding

UK Medical Research Council; British Heart Foundation; Novo Nordisk; National Institute for Health Research; Wellcome Trust; Cancer Research UK.

Integrative analysis of metabolite GWAS illuminates the molecular basis of pleiotropy and genetic correlation

Pleiotropy and genetic correlation are widespread features in genome-wide association studies (GWAS), but they are often difficult to interpret at the molecular level. Here, we perform GWAS of 16 metabolites clustered at the intersection of amino acid catabolism, glycolysis, and ketone body metabolism in a subset of UK Biobank. We utilize the well-documented biochemistry jointly impacting these metabolites to analyze pleiotropic effects in the context of their pathways. Among the 213 lead GWAS hits, we find a strong enrichment for genes encoding pathway-relevant enzymes and transporters. We demonstrate that the effect directions of variants acting on biology between metabolite pairs often contrast with those of upstream or downstream variants as well as the polygenic background. Thus, we find that these outlier variants often reflect biology local to the traits. Finally, we explore the implications for interpreting disease GWAS, underscoring the potential of unifying biochemistry with dense metabolomics data to understand the molecular basis of pleiotropy in complex traits and diseases.

Metabolic biomarker profiling for identification of susceptibility to severe pneumonia and COVID-19 in the general population

Biomarkers of low-grade inflammation have been associated with susceptibility to a severe infectious disease course, even when measured prior to disease onset. We investigated whether metabolic biomarkers measured by nuclear magnetic resonance (NMR) spectroscopy could be associated with susceptibility to severe pneumonia (2507 hospitalised or fatal cases) and severe COVID-19 (652 hospitalised cases) in 105,146 generally healthy individuals from UK Biobank, with blood samples collected 2007-2010. The overall signature of metabolic biomarker associations was similar for the risk of severe pneumonia and severe COVID-19. A multi-biomarker score, comprised of 25 proteins, fatty acids, amino acids, and lipids, was associated equally strongly with enhanced susceptibility to severe COVID-19 (odds ratio 2.9 [95%CI 2.1-3.8] for highest vs lowest quintile) and severe pneumonia events occurring 7-11 years after blood sampling (2.6 [1.7-3.9]). However, the risk for severe pneumonia occurring during the first 2 years after blood sampling for people with elevated levels of the multi-biomarker score was over four times higher than for long-term risk (8.0 [4.1-15.6]). If these hypothesis generating findings on increased susceptibility to severe pneumonia during the first few years after blood sampling extend to severe COVID-19, metabolic biomarker profiling could potentially complement existing tools for identifying individuals at high risk. These results provide novel molecular understanding on how metabolic biomarkers reflect the susceptibility to severe COVID-19 and other infections in the general population.

Learning with multiple pairwise kernels for drug bioactivity prediction

Motivation

Many inference problems in bioinformatics, including drug bioactivity prediction, can be formulated as pairwise learning problems, in which one is interested in making predictions for pairs of objects, e.g. drugs and their targets. Kernel-based approaches have emerged as powerful tools for solving problems of that kind, and especially multiple kernel learning (MKL) offers promising benefits as it enables integrating various types of complex biomedical information sources in the form of kernels, along with learning their importance for the prediction task. However, the immense size of pairwise kernel spaces remains a major bottleneck, making the existing MKL algorithms computationally infeasible even for small number of input pairs.

Results

We introduce pairwiseMKL, the first method for time- and memory-efficient learning with multiple pairwise kernels. pairwiseMKL first determines the mixture weights of the input pairwise kernels, and then learns the pairwise prediction function. Both steps are performed efficiently without explicit computation of the massive pairwise matrices, therefore making the method applicable to solving large pairwise learning problems. We demonstrate the performance of pairwiseMKL in two related tasks of quantitative drug bioactivity prediction using up to 167 995 bioactivity measurements and 3120 pairwise kernels: (i) prediction of anticancer efficacy of drug compounds across a large panel of cancer cell lines; and (ii) prediction of target profiles of anticancer compounds across their kinome-wide target spaces. We show that pairwiseMKL provides accurate predictions using sparse solutions in terms of selected kernels, and therefore it automatically identifies also data sources relevant for the prediction problem.

Availability and implementation

Code is available at https://github.com/aalto-ics-kepaco.

Supplementary information

Supplementary data are available at Bioinformatics online.

Education, employment, absenteeism, and work disability in women with systemic lupus erythematosus

OBJECTIVES

To study education, employment, absenteeism, and work disability (WD) in women with systemic lupus erythematosus (SLE) compared to population controls.

METHOD

The study included 181 women of working age with SLE (mean age 44.0 years, disease duration 12.7 years) and 549 female population controls matched for age living in the same metropolitan area of Helsinki. Data regarding education, employment, absenteeism, and WD in patients and controls were obtained by questionnaire and personal interview.

RESULTS

Basic education, vocational, or academic degrees and occupational categories in patients with SLE were similar to those in controls. In total, 62% of the patients were employed, compared to 77% of the controls (p < 0.001). During the preceding 12 months, employed SLE patients had been on sick leave for 25.4 days vs. 10.2 days in controls (p < 0.001). Subjective work ability regarding physical and mental demands of the job were lower in SLE patients than in controls (p < 0.001 and p = 0.036, respectively). The rate of permanent WD, defined as receiving disability benefits, was 34.3% in SLE patients vs. 10.3% in controls (p < 0.001). Cumulative WD due to SLE 5, 10, and 20 years after the clinical diagnosis was 13, 22, and 47%, respectively.

CONCLUSIONS

SLE does not seem to affect educational achievements and the employment rate for SLE patients is reasonably high. Absenteeism and work disability are, however, 2-3 times more common than in controls. Less than half of the patients were on permanent disability pension due to SLE 20 years after diagnosis of the disease.

Frequency of and risk factors for symptomatic bone fractures in patients with systemic lupus erythematosus

OBJECTIVES

To study risk factors for symptomatic bone fractures in patients with systemic lupus erythematosus (SLE) and to compare the frequency of fractures between SLE patients and population controls.

METHOD

The study included 222 SLE patients [mean age 47.0 years, disease duration 13.1 years, 204 (92%) women] and 720 population controls living in the metropolitan area of Helsinki. The history of symptomatic bone fractures in SLE patients and controls was recorded by interview, and demographic and clinical data of SLE patients were obtained by interview, clinical examination, and chart review.

RESULTS

A history of at least one symptomatic bone fracture was recorded in 93 (42%) of all 222 patients with SLE. The risk of any fracture in 204 women with SLE compared to controls was 1.8 [95% confidence interval (CI) 1.3-2.4] and fractures in the ankle, hip, and vertebral column were more common than in female controls, with odds ratios (ORs) of 2.0 (95% CI 1.1-3.7), 5.1 (95% CI 1.2-21.5), and 4.0 (95% CI 1.8-8.6), respectively. In 18 men with SLE, compared to male controls, no difference in the frequency of fractures was observed (OR 0.7, 95% CI 0.3-2.0). Risk factors for bone fractures in women with SLE were age (p = 0.008), comorbidity (p = 0.050), and the duration of corticosteroid use (p = 0.025).

CONCLUSIONS

Symptomatic bone fractures, especially in the ankle, hip, and vertebral column, are common in women with SLE. Special attention should be paid to preventing fractures in elderly female patients with comorbidities and a long duration of corticosteroid use.

Reproductive health in women with systemic lupus erythematosus compared to population controls

OBJECTIVE

To study the reproductive health history in women with systemic lupus erythematosus (SLE) compared to population controls.

METHODS

A total of 206 female SLE patients were interviewed regarding demographic and disease data, menstruation, use of contraception and hormone replacement therapy (HRT), infertility, and pregnancies. The control group consisted of 1037 women from the general population of similar age and socioeconomic status living in the same region.

RESULTS

In SLE women compared to population controls, mean age at menarche (13.3 vs. 13.2 years) and frequency of infertility (16% vs. 16%) were similar but menopause occurred earlier (44.9 vs. 46.8 years, p = 0.01). Current use of oral contraceptives (OCs) was less common than in controls [18% vs. 28%, odds ratio (OR) 0.55, 95% CI 0.3-1.0] while previous use of progesterone-containing intrauterine devices (IUDs) was more common (13% vs. 5%, OR 3.2, 95% CI 1.9-5.4). Current use of HRT was similar (22% vs. 21%) but SLE patients had started the use earlier (43.2 vs. 47.1 years, p = 0.003). Mean number of pregnancies was lower in SLE patients compared to controls (2.3 vs. 2.5, p = 0.046) and in lupus nephritis patients compared to SLE patients without nephritis (1.9 vs. 2.5, p = 0.01). No difference was found in the occurrence of spontaneous and induced abortions compared to controls, but pregnancy-associated complications were more common in SLE women.

CONCLUSION

When compared to population controls women with SLE are normally fertile, use less OCs and more IUDs, have earlier menopause and use HRT as frequently. Family size is reduced, especially in lupus nephritis patients, and pregnancy-associated complications are more common.

Anti‐nucleosome antibodies in the diagnosis of systemic lupus erythematosus

OBJECTIVE

To study the prevalence and diagnostic significance of antibodies against nucleosomes in patients with systemic lupus erythematosus (SLE) as compared to five anti-nuclear antibody (ANA) assays.

METHODS

The study included 305 patients with SLE, 125 patients with other autoimmune rheumatic diseases, and 415 healthy controls. Anti-nucleosome antibodies were measured by an enzyme-linked immunosorbent assay (ELISA) and ANA by immunofluorescence (IF) using Hep-2 cells. Anti-double-stranded DNA (anti-dsDNA) antibodies were measured by three commercial ELISAs and by IF using Crithidia luciliae as antigen.

RESULTS

Compared to three ELISAs for anti-dsDNA, the anti-nucleosome assay was less sensitive (30% vs. 29-69%) but equally specific (90% vs. 77-95%) for SLE. The most sensitive test was ANA (76%), and the least sensitive was Crithidia (13%). The correlations between the different assays were good (p < 0.001 for all comparisons).

CONCLUSION

The anti-nucleosome antibody assay does not offer additional information compared to conventionally used anti-dsDNA tests in the differential diagnosis of SLE.

The association of antibodies to cardiolipin,β2‐glycoprotein I, prothrombin, and oxidized low‐density lipoprotein with thrombosis in 292 patients with familial and sporadic systemic lupus erythematosus

OBJECTIVE

To determine the prevalence of antibodies to phospholipid-binding plasma proteins (aPL) and to oxidized low-density lipoprotein (OX-LDL), and to study the association of these antibodies with thrombosis and coronary heart disease (CHD) in patients with systemic lupus erythematosus (SLE).

METHODS

Clinical data and sera from 89 Finnish patients with familial and 203 with sporadic SLE were available for the study. Enzyme-linked immunosorbent assays (ELISA) were used for antibody determination.

RESULTS

The occurrence of thrombosis in our SLE patients was 13.7% (40/292) and of clinically diagnosed CHD was 1.4% (4/292). All antibody assays, except IgM-aCL, were significantly associated with thrombosis. IgG-aCL alone or in combination with anti beta 2-GPI or with anti OX-LDL were reasonably sensitive (38%, 48%, and 58%, respectively) and specific (87%, 80% and 72%, respectively) for a history of thrombosis. A high risk of arterial thrombosis (TIA or stroke) was associated with positivity of IgG-aCL, anti beta 2-GPI, and anti-prothrombin. Venous thrombosis was significantly associated with all other assays except IgM-aCL and anti-prothrombin. No test correlated with CHD, but the number of affected patients was small. There were three multiplex SLE families with two patients having a history of thrombosis: no consistent pattern of aPL or anti OX-LDL was found in these patients.

CONCLUSION

IgG-aCL alone or in combination with anti beta 2-GPI or anti OX-LDL are sensitive and specific tests for detecting SLE patients at increased risk of thrombosis. The aetiopathogenesis of thrombosis in familial SLE appears to be multifactorial.

Antibodies to amino acid 200-239 (p200) of Ro52 as serological markers for the risk of developing congenital heart block

Maternal autoantibodies to the p200-epitope of Ro52 have been suggested to correlate with development of congenital heart block. The aim of the present study was to evaluate the clinical relevance and predictive value of p200-antibodies in high-risk pregnancies. Sera from 515 Finnish, Swedish and American women were included in the study. Sera originated from 202 mothers with an infant affected by second- or third-degree atrioventricular block (AVB), 177 mothers with rheumatic disease having infants with normal heart rate and female blood donors (n = 136). A novel serological assay for Ro52 p200-antibodies with intra- and inter-assay variability of 3% and 3.8% respectively was developed. Mothers of children affected by AVB II-III had significantly higher p200-antibody levels than mothers with rheumatic disease having children with normal heart rate (P < 0.001). In the Swedish cohort, a distinction between foetuses with normal conduction, AVB I, AVB II and III was possible. A significant difference in anti-p200 levels between AVB I and AVB II-III groups compared with foetuses with normal conduction (P < 0.05 and P < 0.01) was observed. Using p200-antibodies as a second step analysis in Ro52-positive pregnancies increased the positive predictive value for foetal cardiac involvement (AVB I, II or III) from 0.39 (0.27-0.51) to 0.53 (0.37-0.68). In conclusion, Ro52 p200-antibodies may occur in women with unaffected children, but levels are significantly higher in mothers of children with congenital heart block and are suggested as a relevant marker in evaluating the risk for foetal AV block.

Association of tumour necrosis factor a, b and c microsatellite polymorphisms with clinical disease activity and induction of remission in early rheumatoid arthritis

OBJECTIVE

To study the associations of tumor necrosis factor (TNF) a, b and c microsatellite markers with 1) the clinical disease activity and 2) the induction of remissions in patients with early rheumatoid arthritis (RA) treated with two treatment strategies.

METHODS

In the FIN-RACo (FINnish Rheumatoid Arthritis Combination therapy) trial of two years, 195 patients with recent-onset RA were randomly assigned to receive either a combination (COMBI) (sulphasalazine, methotrexate, hydroxychloroquine, and prednisolone) or a single (SINGLE) (initially sulphasalazine with or without prednisolone) disease modifying antirheumatic drug (DMARD) therapy. TNF a, b and c microsatellite and HLA-DRB1 typings were carried out in 165 (79 COMBI; 86 SINGLE) study completers.

RESULTS

At baseline the 28 joint disease activity scores (DAS28) of the patients positive for TNFa2, a13 or b1 microsatellite markers were significantly higher than in the other patients. In the SINGLE patients the DAS28 improved comparably in patients with (n = 31) or without (n = 53) the TNFb1 marker (NS), while the DAS28 of the TNFb1-positive COMBI patients (n = 22) improved significantly more than that of the TNFb1-negative cases (n = 57) (p = 0.014). Respective 31.8% (7/22) and 28.1% (16/57) of the COMBI patients with or without TNFb1 allele achieved remission at one year. The corresponding figure in SINGLE patients were 0% (0/31) and 20.8% (11/53) (p = 0.006). At two years the remission frequencies in the TNFb1+/TNFb1- patients in the COMBI and SINGLE were 50.0%/38.6% and 9.7%/22.6%, respectively.

CONCLUSION

Early TNFb1+ RA patients have more active disease but respond more favourably to COMBI treatment than the patients without this microsatellite allele. The finding may be of clinical relevance for the choice of DMARDs in early RA.

Serum soluble interleukin-2 receptor predicts early remission in patients with recent-onset rheumatoid arthritis treated with a single disease-modifying antirheumatic drug

OBJECTIVE

To study the value of baseline serum levels of circulating soluble interleukin-2 receptor (sIL-2R) and soluble E-selectin as predictors of early remission in patients with recent-onset rheumatoid arthritis (RA) receiving a single disease-modifying anti-rheumatic drug (DMARD) (SINGLE) or therapy with a combination of DMARDs (COMBI).

METHODS

Baseline (n = 157) serum samples originate from the FIN-RACo (FINnish Rheumatoid Arthritis Combination therapy) trial, in which 195 patients with early and clinically active RA were randomly assigned to receive either SINGLE (initially sulfasalazine) with or without prednisolone, or COMBI therapy (sulfasalazine, methotrexate, hydroxychloroquine, and prednisolone). Of the samples, 76 were from SINGLE patients and 81 from COMBI patients. sIL-2R was measured by automated immunoassay analyzer and sE-selectin by enzyme-linked immunosorbent assay.

RESULTS

At six months, 7 (9% [95% CI: 4 to 18]) SINGLE and 19 (23% [95% CI: 15 to 34]) COMBI patients were in remission. In multivariate logistic regression analysis, sIL-2R <442 U/ml and COMBI therapy were the only predictors of remission. The area under receiver operating characteristic curve for sIL-2R level was 0.86 (95% CI: 0.62 to 0.95) in SINGLE and 0.57 (95% CI: 0.42 to 0.71) in COMBI (p = 0.006). In SINGLE, the optimal cut offpoint was 442 U/ml, lower levels predicting remission with sensitivity of 83% (95% CI: 73% to 91%) and specificity of 86% (95% CI: 42% to 100%). Likelihood ratio for positive test was 5.9 (95% CI: 1.6 to 32.8). In multivariate logistic regression analysis, sIL-2R <442 U/ml and COMBI therapy were the only predictors of remission.

CONCLUSION

Low baseline serum sIL-2R level predicts early remission of patients with active early RA treated with a single DMARD.

Anti-telomere antibodies in systemic lupus erythematosus (SLE): a comparison with five antinuclear antibody assays in 430 patients with SLE and other rheumatic diseases

OBJECTIVE

To investigate the prevalence and diagnostic significance of antibodies against telomeric DNA in systemic lupus erythematosus (SLE) and other autoimmune rheumatic diseases, and to make comparisons with five conventional anti-DNA or anti-nuclear antibody (ANA) assays.

METHODS

Antibodies to telomeres, which are highly repetitive sequences of DNA (TTAGGG/CCCTAA) at the end of eukaryotic chromosomes, were measured by an enzyme linked immunosorbent assay (ELISA) in 305 patients with SLE and 125 patients with other autoimmune rheumatic diseases (78 rheumatoid arthritis, 32 primary Sjögren's syndrome, eight mixed connective tissue disease, seven miscellaneous rheumatic diseases). Other assays used were two commercial ELISA assays for anti-dsDNA using calf thymus as antigen, Crithidialuciliae immunofluorescence, and radioimmunoassay (RIA) for anti-dsDNA and immunofluorescence using Hep-2 cells for ANA.

RESULTS

The prevalence of anti-telomere in SLE was 60%, v 5% in rheumatoid arthritis and 18% in other autoimmune rheumatic diseases. Specificity of anti-telomere for SLE was 91%; positive and negative predictive values were 95% and 46%, respectively. For anti-dsDNA by two ELISA assays using calf thymus as antigen, sensitivities were 69% and 29% and specificities 66% and 96%, respectively. Other anti-dsDNA assays had low sensitivities (RIA 43%, Crithidia immunofluorescence 13%). The association of anti-telomere with a history of nephritis in patients with SLE was stronger (p = 0.005) than by any other assay (p = 0.006-0.999). The correlations between the different assays were good (p<0.001 for all comparisons).

CONCLUSIONS

The new ELISA for anti-telomere antibodies using standardised human dsDNA as antigen is a sensitive and highly specific test for SLE.

Relationship of maternal autoimmune response to clinical manifestations in children with congenital complete heart block

OBJECTIVE

To study the autoimmune response in mothers of children with congenital heart block (CHB) diagnosed at different ages and with different clinical manifestations.

PATIENTS AND METHODS

Clinical data and sera for the determination of immunological tests were available from 104 mothers of 113 children born between 1950 and 2000 and diagnosed with CHB before the age of 16 y. Prenatal diagnosis was performed in 74 (65%) children of 65 mothers, and 39 (35%) children had postnatal diagnosis of CHB. Maternal antibodies to 52 kd and 60 kd SS-A, and to 48 kd SS-B were determined by time-resolved fluoroimmunoassay (TR-FIA) and to antinuclear antibodies (ANA) by immunoflurescense (IF).

RESULTS

Out of the 65 mothers of children with in utero diagnosed CHB, 88% had antibodies to 52 kd SS-A and 83% had ANA. Antibodies to 60 kd SS-A and 48 kd SS-B were less frequently present, in 48% and in 54% of the mothers, respectively. Seven (11%) of the mothers were negative by all immunoassays. Of the 13 mothers of children with in-infancy diagnosed CHB, one mother had high-titer ANA. After 1 y of age, CHB was diagnosed in 26 children; at 1 to 6 y in 16 and after 7 y in 10 children; 1/16 and 1/10 patients had positive antibodies. In all twin pregnancies (n = 4) and in all families with recurring cases of CHB (n = 5), maternal antibodies were positive in at least one assay. The titer of 48 kd anti-SS-B antibodies was significantly higher in children with cutaneous neonatal lupus (98.1 vs 41.0; p = 0.02). All mothers whose children died before the age of 4 y (n = 8) and 85% (11/13) of mothers whose children developed cardiomyopathy had elevated antibody titers in at least one assay. However, we could not find any prognostic value of maternal antibody levels or specificities on the clinical outcome of the children with CHB.

CONCLUSIONS

Although rare, late detection or postnatal progression of CHB in antibody-mediated CHB should be taken into consideration. Maternal antibody levels or specificities have prognostic effect neither on the clinical outcome of the child with CHB nor on the risk of reappearance in the same family.

Peptidylarginine deiminase, the arginine to citrulline converting enzyme, is frequently recognized by sera of patients with rheumatoid arthritis, systemic lupus erythematosus and primary Sjögren syndrome

OBJECTIVE

Antibodies to citrulline-containing epitopes of filaggrin are highly specific for rheumatoid arthritis (RA). We studied whether the enzyme peptidylarginine deiminase (PAD), responsible for the post-translational modification of peptide-bound arginine residues to citrulline, constitutes an antigen for patients with RA.

METHODS

IgG antibodies to PAD were measured by enzyme-linked immunosorbent assay (ELISA) in sera from patients with RA, systemic lupus erythematosus (SLE), primary Sjögren syndrome (pSS), multiple sclerosis (MS) and healthy controls.

RESULTS

Compared to healthy controls, raised levels of IgG antibodies to PAD were found in 50 of 57 recent-onset RA patients (88%) and in 40 (70%) of the same 57 patients 3 years later (p<0.0001 for both comparisons). Eleven of 51 (22%) patients with RA of long duration, 19/43 (44%) patients with SLE and 16/19 (84%) patients with pSS, but none of 20 patients with MS, had elevated anti-PAD levels.

CONCLUSION

The arginine-citrulline converting enzyme PAD was recognized as a new antigen against which patients with inflammatory rheumatic diseases frequently show IgG class antibodies.

Pregnancy and lupus nephritis

Family planning and pregnancy are important and usually problematic issues for a young woman with lupus nephritis. Moderate renal insufficiency and previous use of alkylating cytotoxic drugs are associated with decreased fertility. Oral contraceptives containing synthetic estrogens are contraindicated in women with active lupus nephritis, uncontrolled hypertension, history of thromboembolic diseases or high levels of antiphospholipid antibodies. Mild flares of systemic lupus erythematosus (SLE) are common during pregnancy, severe renal flares and permanent impairment of renal function are uncommon. The outlook of pregnancy for women with lupus nephritis is usually favourable if the disease (both renal and nonrenal) has been quiescent for at least 6 months before pregnancy, and if, at conception, serum creatinine is less than 140 micromol/l, proteinuria less than 3 g/24 h and blood pressure controlled. The risk of fetal loss is, however, at least 2-3 times higher than in the normal population and pre-eclampsia, prematurity and fetal growth retardation frequently complicate these pregnancies. Especially poor fetal outcome is associated with antiphospholipid antibodies. Pregnancies in women with lupus nephritis require intense fetal and maternal surveillance.

Familial systemic lupus erythematosus in Finland

OBJECTIVE

To perform a cross sectional nation-wide clinical study of familial systemic lupus erythematosus (SLE) in Finland.

METHODS

We sought to identify all Finnish families in which at least 2 members satisfied the classification criteria for SLE. About 1,200 patients with SLE (80-85% of all patients attending Finnish hospitals) were contacted. Personal and/or phone interviews and examination of medical records were used to verify the diagnoses. A comparison of clinical characteristics was made between familial cases of SLE and matched sporadic controls.

RESULTS

We identified 53 multiplex families with 113 SLE patients. Forty-six families had 2 affected members and 7 families had 3 affected members. There were 3 pairs of monozygotic female twins and one pair of dizygotic twins of the opposite sex concordant for SLE. Eleven (9.7%) of the 113 familial cases of SLE were male. No differences were found in the clinical presentation of SLE between familial and sporadic cases (sex, age at onset, major clinical manifestations, and common laboratory tests). The incidence of familial SLE was approximately 4-5%.

CONCLUSION

Our study shows that familial and sporadic SLE are not different disease entities; this means that we can extrapolate the results of future genetic analyses in multiplex SLE families to all patients with SLE.

Long-term outcome of mothers of children with isolated heart block in Finland

OBJECTIVE

To study the long-term outcome of mothers of children with isolated heart block in a defined population.

METHODS

We reviewed the Finnish hospital registries for patients born between 1950 and 1999 who had been diagnosed as having isolated heart block before the age of 15 years. We identified 101 children with isolated congenital heart block (CHB) and 55 with isolated heart block detected after the newborn period. Eighty-three (91%) of the 91 mothers of children with CHB and 48 (87%) of the 55 mothers of children with heart block detected after the newborn period were studied according to a protocol defining clinical characteristics (mean 9.9 years, range 0-49 years, and mean 22.9 years, range 4-47 years after the index delivery, respectively). Maternal survival was compared with survival in an age-matched population of normal Finnish women.

RESULTS

Before the index delivery, 29 (37%) of the 78 surviving mothers of children with CHB had a self-reported clinical diagnosis of a chronic autoimmune disease, and 55 (71%) had had symptoms, signs, or abnormal laboratory findings suggesting an underlying subclinical disease. Of the 23 mothers who were completely asymptomatic before the index delivery, 10 (13% of the surviving mothers) remained so after a mean followup of 9.6 years (range 0-21 years). In mothers of children with CHB, clinical characteristics different from those of healthy mothers were photosensitivity, fatigue, dry eyes, and dry mouth. Forty-eight (58%) of these 83 mothers developed an autoimmune disease during followup. The most common diagnosis was primary Sjögren's syndrome (22 definite, 11 probable), followed by systemic lupus erythematosus (SLE). The standardized mortality ratio of mothers of children with CHB was 5.1, and 3 of the 5 deaths were associated with SLE. Mothers of children with heart block detected after the newborn period had similar symptoms and signs of autoimmune diseases as the healthy controls, and their standardized mortality ratio was 1.9.

CONCLUSION

Primary Sjögren's syndrome, either definite or subclinical, is the predominant autoimmune disorder in mothers of children with CHB. Mothers of children with isolated heart block detected after the newborn period do not, as a group, have clinical features suggestive of autoimmune diseases.

Hormone replacement therapy in women with rheumatic diseases

Hormone replacement therapy (HRT) for the treatment of menopausal symptoms and for the prevention of osteoporosis and cardiovascular diseases has clearly increased during the last decades. Women with rheumatic diseases, especially when using corticosteroids, are in a high risk of osteoporotic fractures and atherosclerotic disease, which cause significant morbidity and mortality in later life. In this review, the benefits and risks of HRT in postmenopausal women are reviewed in general and, in particular, in women with rheumatic diseases.

Short- and long-term outcome of children with congenital complete heart block diagnosed in utero or as a newborn

OBJECTIVES

Few data are available in the literature regarding the long-term outcome of newborns with congenital complete heart block (CHB). The aims of this retrospective study were to assess neonatal morbidity and mortality, incidences of dilated cardiomyopathy (DCM), and associated heart defects, and to establish prenatal and postnatal factors that might predict adverse outcome in children with CHB.

DESIGN AND SETTING

The cohort includes 91 infants with CHB diagnosed in 5 tertiary centers in Finland between 1950 and 1998.

PATIENTS

Maternal connective tissue disease was evident in 89% of the patients. At birth, the median gestational age was 37.1 weeks, and the median weight was 2969 g. Of the 91 infants, 60 (66%) were girls and 7 (8%) were twins.

RESULTS

Incidences of perinatal morbidity and mortality were 58% and 7%, respectively. The total mortality of CHB was 16%; 11 of 15 (73%) died during the first 12 months. Cumulative probability of survival at 10 years old was 82%. Pacing as a newborn was indicated in 48 of 90 cases (53%), and 36 received pacemakers at older ages. Cardiac defects not causally related to CHB were found in 38 of 90 patients (42%), of whom 22 were operated on. DCM was found in 21 (23%), of whom 13 died. During the follow-up, among 75 survivors with a median age of 9 years, 54 (72%) are free from symptoms. Poor outcome defined as clinically or pathologically evident congestive DCM was associated with intrauterine hydrops, low fetal and neonatal heart rate, low birth weight, male sex, and neonatal problems attributable to prematurity or neonatal lupus.

CONCLUSIONS

Despite early pacing, CHB carries high mortality during the first 12 months of life. High incidences of DCM and associated heart defects indicate close echocardiographic monitoring of all children with CHB.

Comparison of combination therapy with single-drug therapy in early rheumatoid arthritis: a randomised trial. FIN-RACo trial group

BACKGROUND

The treatment of rheumatoid arthritis should aim at clinical remission. This multicentre, randomised trial with 2-year follow-up sought evidence on the efficacy and tolerability of combination therapy (sulphasalazine, methotrexate, hydroxychloroquine, and prednisolone) compared with treatment with a single disease-modifying antirheumatic drug, with or without prednisolone, in the treatment of early rheumatoid arthritis.

METHODS

199 patients were randomly assigned to two treatment groups. 195 started the treatment (97 received combination and 98 single drug therapy). Single-drug therapy in all patients started with sulphasalazine; in 51 patients methotrexate was later substituted. Oral prednisolone was required by 63 patients. The primary outcome measure was induction of remission. Analyses were intention to treat.

FINDINGS

87 patients in the combination group and 91 in the single-therapy group completed the trial. After a year, remission was achieved in 24 of 97 patients with combination therapy, and 11 of 98 with single-drug therapy (p=0.011). The remission frequencies at 2 years were 36 of 97 and 18 of 98 (p=0.003). Clinical improvement (American College of Rheumatology criteria of 50% clinical response) was achieved after 1 year in 68 (75%) patients with combination therapy, and in 56 (60%) using single-drug therapy (p=0.028), while at the 2-year visit 69 and 57 respectively (71% vs 58%, p=0.058) had clinically improved. The frequencies of adverse events were similar in both treatment groups.

INTERPRETATION

Combination therapy was better and not more hazardous than single treatment in induction of remission in early rheumatoid arthritis. The combination strategy as an initial therapy seems to increase the efficacy of the treatment in at least a proportion of patients with early rheumatoid arthritis.

Role of HLA in congenital heart block: susceptibility alleles in children

Congenital heart block (CHB) is a syndrome of uncertain pathogenesis leading to cardiac conduction disturbances in the foetus and newborns. It has been proposed that maternal antibodies transmit immunological injury in the developing foetal heart, thus causing irreversible damage of the atrioventricular node, leading to third-degree atrioventricular block. However, some genetic or environmental factors may also be involved. We have searched for genetic markers that play a role in immune response and that would be pathognomonic for the disease, either in mothers by regulating their immune response or in children by affecting antigen presentation and target for the maternal immune response. We have compared HLA class I and II alleles of the children with their mother and with healthy individuals and searched for HLA markers that would be emphasized in children. We have shown that particular DQ alleles in the child predispose to CHB, perhaps serving as antigen-presenting molecules on site. In addition, the HLA-Cw3 allele is involved, although its function remains to be clarified. In our results, children with CHB were often identical to their mothers in alleles of DRB, DQA and DQB loci, thus affecting foetomaternal recognition and suggesting that cell-mediated mechanisms could be involved in the pathogenesis.

Role of HLA in congenital heart block: susceptibility alleles in mothers

In congenital heart block (CHB), abnormal maternal immunisation leads to autoantibody production against SS-A/Ro and SS-B/La antigens. These maternal antibodies are transferred across the placenta to the unborn child and are believed to transmit irreversible immunological injury in developing foetal heart tissue, thus causing 3rd-degree atrioventricular block. The mothers may suffer from systemic lupus erythematosus (SLE) or primary Sjögren's syndrome (SS), but they may be asymptomatic. Women with primary SS show a typical autoimmune HLA antigen pattern, namely higher frequency of HLA B8 and DR3 than in the normal population. The HLA pattern may affect individual ability to resist infecting bacteria and viruses and to response in various ways to autoantigens. It is probable that other factors such as genetic regulation of immune response are involved in CHB. We compared the HLA class I and class II alleles of mothers having CHB children with those of women suffering from primary SS and having healthy children, and with those of healthy Finns. Antibodies against 52-kD and 60-kD SS-A/Ro and 48-kD SS-B/La antigens were compared between the two groups of mothers. Our results show that anti-SS-A/Ro antibody-positive mothers all show a strong association with known autoimmune-predisposing HLA alleles, however, the mothers of CHB children differ in some HLA class I alleles, and especially in HLA haplotypes, from mothers of healthy children. Mothers with HLA A1, Cw7, B8 and without B15 are at particularly high-risk of having CHB children.

Recurrent miscarriage, congenital heart block and systemic lupus erythematosus

We report the obstetric history of a woman, who between 15 spontaneous abortions, gave birth to a child with congenital heart block. She later developed systemic lupus erythematosus, had antibodies to SS-A/Ro and SS-B/La but was repeatedly negative for antiphospholipid antibodies.

Renal lupus in pregnancy

The outlook of pregnancy for women with lupus nephritis is usually favourable if the disease has been quiescent for at least 3 months before pregnancy, and if, at conception, serum creatinine is less than 140 mumol/l, proteinuria less than 3 grams/25 hours and blood pressure controlled. The risk of fetal loss is, however, 2-3 times higher than in the normal population and pre-eclampsia, prematurity and fetal growth retardation frequently complicate these pregnancies. Pregnancies in women with lupus nephritis are high-risk pregnancies and they require intense fetal and maternal surveillance.

Immune-mediated congenital heart block (CHB): identifying and counseling patients at risk for having children with CHB

OBJECTIVE

To identify patterns of maternal antibodies associated with an increased risk of having a child with congenital heart block (CHB) and to provide a basis for counseling women with a previously affected child.

METHODS

This retrospective clinical study of the obstetric histories of 46 Finnish women with a CHB child compared the strength and specificity of the immune response to SS-A/Ro and SS-B/La, as determined by immunoblot and ELISA, in 44 affected women with 85 women with systemic lupus erythematosus (SLE) and 32 women with primary Sjögren's syndrome (SS) with healthy children.

RESULTS

High levels of anti-SS-A/Ro and anti-SS-B/La by practically all assays were associated with a significantly increased risk of having a CHB child. The best single test to identify high-risk mothers was anti-52 kd SS-A/Ro by immunoblot (OR 18.9), and it was the only assay to detect mothers at increased risk of CHB as compared with controls with primary SS. Low risk of CHB was indicated by undetectable or low levels of antibodies in the ELISA assays and no reactivity on immunoblot. Mothers with a previous child with CHB had a history of fetal loss (mostly spontaneous abortions) or a history of recurrent fetal losses (> or = 3) slightly more often than controls. Late-trimester obstetric complications in non-CHB pregnancies were insignificant. The relative risk for a female child compared with a male child to have CHB was 1.9 (1.2-2.9, P = .009), and the risk of the mother having another child with CHB was 12% (4 of 34).

CONCLUSION

Although there is no unique antibody profile specific for CHB, mothers with a high or low risk of having a child with CHB can be identified. Female children appear to have an increased risk of CHB, but the risk of the mother having another child with CHB is low.

Congenital heart block: HLA differences between affected children and healthy siblings in four Finnish families

Congenital heart block without intracardiac anatomic malformations is a potentially lethal disease affecting children and newborns. The mother often has an autoimmune disorder with autoantibodies against SS-A/Ro and/or SS-B/La antigens. However, only a minority of the children of these mothers develop complete heart block. It is believed that the maternal antibodies are pathogenic, but other immunological mechanisms such as cell-mediated injury cannot be excluded. Maternal cells may recognize fetal antigens adjacent to fetal HLA, and thus some children may be more susceptible to heart block than others, depending on their HLA genetics. The purpose of this study was to evaluate whether there are HLA differences between children with heart block and their healthy siblings. Six affected children in four families and their siblings were studied. MHC class I were typed serologically and class II and some non-HLA alleles were typed by DNA techniques. DQB1*03/04 were seen more often in the affected children than in the siblings. Some other differences were also seen in the other antigens of the MHC area.

Thrombolysis for acute ischemic stroke in the primary antiphospholipid syndrome

Successful intravenous thrombolytic treatment for acute major ischemic stroke was given to a 24-year-old woman with primary antiphospholipid syndrome. Our patient was a smoker and used oral contraceptives containing estrogen at the time of the stroke. We discuss risk factors for stroke and the treatment of arterial thrombosis in patients with antiphospholipid antibodies.

Antibodies binding to anionic phospholipids but not to oxidized low-density lipoprotein are associated with thrombosis in patients with systemic lupus erythematosus

OBJECTIVE

Elevated levels of antibodies against oxidized low-density lipoprotein (LDL) frequently occur in patients with systemic lupus erythematosus (SLE) and these antibodies crossreact in many sera with anticardiolipin antibodies, known to be associated with thrombosis. Therefore, a study was carried out to assess the mutual relationship between antibodies against oxidized LDL and thrombosis.

METHODS

The occurrence of IgG class antibodies against oxidized LDL, cardiolipin and phosphatidyl serine were determined by enzyme-linked immunosorbent assay in a series of 146 patients with SLE. Twenty-one patients had had thromboembolic complications. At least one of three tests used to detect lupus anticoagulant was positive in 34 out of 133 patients.

RESULTS

The level of antibodies against oxidized LDL correlated significantly with that of antibodies against cardiolipin (r = 0.52) but only marginally with antibodies against phosphatidyl serine (r = 0.18). Antibodies against cardiolipin and phosphatidyl serine, but not those against oxidized LDL, were significantly associated with the presence of lupus anticoagulant (odds ratios of the risk in the highest tertile relative to the lower tertiles of the antibody were 5.3, 6.9 and 1.1, respectively) and with thrombosis (odds ratios 2.5, 4.0 and 1.0, respectively).

CONCLUSION

The observations suggest that only those antibodies reacting specifically with cardiolipin and phosphatidyl serine are associated with thrombosis and with the presence of lupus anticoagulant in patients with SLE, whereas antibodies crossreacting with oxidized LDL and those reacting specifically with oxidized LDL are not associated.

Antibodies to phospholipid-binding plasma proteins and occurrence of thrombosis in patients with systemic lupus erythematosus

There is accumulating evidence that anti-phospholipid (aPL) antibodies in the sera of patients with autoimmune diseases bind to a complex of anionic phospholipids and plasma phospholipid-binding proteins, namely beta 2-glycoprotein I (beta 2-GPI) and prothrombin. It has been suggested that a conformational change in beta 2-GPI, induced by binding either to anionic phospholipids or to the oxygen molecules on the irradiated microtiter plate, reveals cryptic antigenic epitope(s) in the native protein. We used an enzyme-linked immunoassay for measuring antibodies against two phospholipid-binding proteins, i.e., beta 2-GPI and prothrombin, absorbed to an irradiated plate in an unselected series of 139 patients with systemic lupus erythematosus (SLE). Elevated levels of antibodies against beta 2-GPI were found in 49% of patients and antibodies against prothrombin in 34% of patients. Both antibodies were significantly associated with deep venous thrombosis in patients with SLE (P = 0.009 for both antibodies). Accordingly, testing of these antibodies seems to be clinically useful in evaluating the risk of thrombosis.

Maternal HLA antigens and antibodies to SS-A/Ro and SS-B/La. Comparison with systemic lupus erythematosus and primary Sjögren's syndrome

To study the maternal immunogenetics in congenital heart block (CHB), 31 mothers of affected children were HLA typed for class I and II antigens, and the results were compared with the corresponding HLA types in 900 healthy controls, in 45 mothers with systemic lupus erythematosus (SLE) and in 21 mothers with primary SS who had healthy children. An enzyme-linked immunosorbent assay was used to study the autoantibody responses to the recombinant 52 and 60 kDa SS-A/Ro, and 48 kDa SS-B/La proteins, and to the affinity-purified SS-A/Ro and SS-B/La antigens. Mothers of children with CHB had HLA B8 and DR3 significantly more often than healthy controls [71 vs 10%; relative risk (RR) 9.8, P < 0.00001 and 74 vs 23%; RR9.8, P < 0.001, respectively]. HLA B35 was protective (RR 0.1, P = 0.0029). Compared to controls with SLE, mothers of children with CHB were more often HLA DR3 and DQ2 positive (RR 4.1, P = 0.0057 and RR 3.1, P = 0.031, respectively), and compared to controls with primary SS less often HLA B15 positive (RR 0.1, P = 0.010). In general, the HLA antigen profile in mothers of children with CHB was more closely related to primary SS than to SLE. Levels of antibodies to all three SS-A/Ro antigens were significantly higher in mothers of children with CHB than in controls with SLE and primary SS (P = 0.0001-0.0014). With regard to SS-B/La, the autoantibody responses were similar (P = 0.32-0.66).(ABSTRACT TRUNCATED AT 250 WORDS)

Fetal outcome in women with primary Sjögren's syndrome. A retrospective case-control study

OBJECTIVE

To study fetal outcome in women with primary Sjögren's syndrome (SS) compared to that in women with systemic lupus erythematosus (SLE) and healthy women, and to study the possible association of fetal loss with anticardiolipin antibodies (aCL) and antibodies to SS-A/Ro and SS-B/La in women with primary SS.

METHODS

A retrospective analysis of the fetal outcome in 55 pregnancies in 21 patients with primary SS compared to that in 100 pregnancies in 42 patients with SLE and 94 pregnancies in 42 healthy women matched for age, parity and the onset of the autoimmune disease with respect to pregnancy. IgG-, IgM- and IgA-aCL were determined by a cofactor-dependent ELISA and antibodies to SS-A/Ro and SS-B/La by ELISA using human recombinant antigens and affinity-purified antigens.

RESULTS

Of all the 55 pregnancies in patients with primary SS, 8 (15%) occurred after the onset of primary SS symptoms. Eleven (20%) of the 55 pregnancies ended in fetal loss. The relative risk (RR) for fetal loss in patients with primary SS was 2.7 (95% CI 1.1-6.5; p = 0.023), and after the exclusion of the patient with four spontaneous abortions it was 2.0 (0.7-5.3; p = 0.18). In SLE the level of risk was 2.2 (0.9-5.0; p = 0.065). Fetal loss in patients with primary SS was not associated with elevated levels of anticardiolipin antibodies (aCL) or autoantibodies to SS-A/Ro or SS-B/La. Newborns of mothers with primary SS were not more premature or growth retarded than newborns of healthy women, but the absolute and the relative birth weights of the newborns of mothers with SLE was significantly lower than in healthy controls (P < 0.001 and P < 0.0001, respectively).

CONCLUSION

We conclude that the majority of pregnancies in women with primary SS occur before the onset of the disease and that these women have an increased risk of fetal loss, which is not associated with elevated levels of ACL or antibodies to SS-A/Ro or SS-B/La. The risk of fetal loss in primary SS is similar to that in women with SLE, but fetal growth retardation appears to be more common in SLE than in primary SS.

Isolated congenital heart block. Long-term outcome of mothers and characterization of the immune response to SS-A/Ro and to SS-B/La

OBJECTIVE

To study the long-term outcome of mothers of children with isolated congenital heart block (CHB) and to characterize the maternal autoantibody response to SS-A/Ro and SS-B/La.

METHODS

A retrospective clinical study of 33 mothers a mean of 11.2 years (SD 9.2 years, range 0-32 years) after the delivery of their first child with CHB. A clinical and immunologic study of 31 of these mothers, compared with 89 healthy mothers, 45 mothers with systemic lupus erythematosus (SLE), and 19 mothers with primary Sjögren's syndrome (SS), all of whom had healthy children. The specificity of the autoantibody responses to SS-A/Ro and SS-B/La was studied by enzyme-linked immunosorbent assays using purified human recombinant antigens and affinity-purified antigens.

RESULTS

By the time of the analysis, 2 (6%) of the 33 mothers of CHB children had died and 6 (18%) had met the criteria for SLE. As a group, mothers of CHB children had clinical and immunologic characteristics more closely related to primary SS than to SLE or any other connective tissue disease. The predominant autoantibody response was to the SS-A/Ro antigens, notably to the 52-kd SS-A/Ro protein (prevalence 97%). Compared with controls with SLE, mothers of CHB children had higher titers of antibodies to recombinant 52-kd and 60-kd SS-A/Ro proteins and to the affinity-purified SS-A/Ro antigen (P < 0.05, P < 0.01, and P < 0.001, respectively). Compared with controls with primary SS, the autoantibody responses were similar.

CONCLUSION

The predominant autoimmune disorder in mothers of children with CHB is subclinical primary SS. Antibodies to SS-A/Ro appear to be a prerequisite for the development of CHB.

Congenital heart block in one of the HLA identical twins

A case of HLA identical twins with one affected by congenital heart block is reported. Both twins, as their mother, had more than 12-fold higher anti-Ro antibody titers compared to healthy controls, but no differences were observed between the affected and the healthy baby. It is possible that there is a third factor causing the manifestation of this disease.

Isolated congenital heart block: fetal and infant outcome and familial incidence of heart block

OBJECTIVE

To determine the 1-year outcome of infants with isolated congenital heart block, the risk of fetal loss in mothers of affected infants, and the risk of recurrence of congenital heart block.

METHODS

The outcomes of 34 infants with isolated congenital heart block and of the 109 pregnancies in the 32 mothers of these infants were analyzed retrospectively. A control group consisted of 170 pregnancies in 64 women individually matched for age, parity, and socioeconomic status.

RESULTS

Five (15%) of the 34 infants with isolated congenital heart block died before 1 year of age. The relative risk for fetal loss in mothers of affected children, after the exclusion of a mother with 16 spontaneous abortions, was 1.9 (95% confidence interval 0.9-3.8; P = .094). The prevalence of congenital heart block in all siblings of children with congenital heart block was 4% (two of 45). The risk of having a child with congenital heart block after a previous birth of an affected child was 8% (two of 26).

CONCLUSIONS

Infant mortality in isolated congenital heart block is considerable, and mothers of affected children tend to have an increased risk of fetal loss. However, the risk of recurrence of congenital heart block is low.

Pregnancy in lupus nephropathy

The purpose of this study was to obtain information about the fetal and maternal outcome of pregnancy in patients with pre-existing lupus nephritis and to evaluate risk factors for poor fetal outcome. Twenty-six pregnancies in 16 patients were retrospectively analyzed. Induced abortions were performed in two patients and one patient had a spontaneous abortion. Of the 23 completed pregnancies, all clinically established on inactive lupus nephritis with normal renal function, seven (30%) were complicated by pre-eclampsia. Two of the three patients with severe pre-eclampsia had increased levels of antiphospholipid antibodies (aPL). Of the 23 newborns, seven (30%) were premature (< 37 weeks) and seven (30%) had neonatal complications. Six of the seven pregnancies associated with neonatal complications were hypertensive. There was one early neonatal death. Four newborns (16%) were severely growth retarded (< -2 SD). The presence of hypertension before pregnancy tended to correlate with low relative birth weight in the newborns (p = 0.079). Flares of systemic lupus erythematosus (SLE) during pregnancy and six months post partum occurred in two (9%) of the 23 completed pregnancies. Renal function was not affected irreversibly in any patient. Thus, the outlook for pregnancy in patients with stable lupus nephritis at conception is good. However, the risk of obstetric complications is greater and fetal morbidity, especially in hypertensive pregnancies, is common.

Fetal outcome in lupus pregnancy: a retrospective case-control study of 242 pregnancies in 112 patients

Fetal outcome in systemic lupus erythematosus (SLE) was retrospectively analysed in 242 pregnancies in 112 unselected patients, and the outcome was compared with that of 417 pregnancies in 192 control women matched for age, parity and socio-economic status. Relative risk for fetal loss after the diagnosis of SLE was 2.5 (95% confidence interval (CI), 1.4-4.5), for prematurity 5.8 (3.2-10.5) and for intra-uterine growth retardation (IUGR) 8.6 (3.0-24.3). Fetal outcome of pregnancy in patients with pre-existing stable lupus nephritis was no worse than in other SLE pregnancies. Relations of three lupus anticoagulant (LA) assays and tree anticardiolipin (aCL) enzyme-linked immunosorbent assays to fetal outcome were studied. Patients positive by any LA assay had a previous fetal loss more often than patients negative by all LA assays (odds ratio 3.4; 95% CI, 1.3-9.0; P = 0.01). Of the 41 patients whose antiphospholipid antibody (aPL) tests were all negative, five (12%) had a history of fetal loss (16% in controls). As a group, aCL was more sensitive for fetal loss than LA (64% vs 50%), but LA was more specific (77% vs 52%). Combinations of one aCL assay with one LA assay had a 41-73% sensitivity and a 64-73% specificity for a history of fetal loss. aPL did not correlate to prematurity or fetal growth retardation. In conclusion, fetal loss in SLE is 2.5 times more prevalent than in the normal population. The presence of LA indicates a high risk for fetal loss, and the absence of aPL is an indication of a favorable pregnancy outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Production of prostacyclin and thromboxane in lupus pregnancies: effect of small dose of aspirin

OBJECTIVES

To find out whether the tendency toward poor outcome in lupus pregnancies could be explained by changes in prostacyclin/thromboxane production, to relate these changes to the presence of antiphospholipid antibodies, and to study the potential benefits of low-dose aspirin.

METHODS

We followed the urinary output of prostacyclin metabolites (6-keto-prostaglandin [PG]F1 alpha, 2,3-dinor-6-keto-PGF1 alpha) and thromboxane metabolites (thromboxane B2, 2,3-dinor-thromboxane B2) using high-pressure liquid chromatography followed by radioimmunoassay. We studied 14 pregnant women with systemic lupus erythematosus (SLE), of whom six had detectable antiphospholipid antibodies. The patients were randomized by a computerized program to receive either 50 mg aspirin daily (six women) or placebo (eight women). Nine healthy pregnant women served as controls.

RESULTS

The production of prostacyclin was normal in early pregnancy in SLE patients but was reduced during late gestation in those without antiphospholipid antibodies. The production of thromboxane was increased in SLE patients compared with controls, and this increase was highest (two-to threefold rise) when antiphospholipid antibodies were detectable. Aspirin eliminated thromboxane dominance without affecting prostacyclin production.

CONCLUSION

These data suggest that the presence of antiphospholipid antibodies in SLE patients may trigger thromboxane dominance, possibly contributing to the adverse outcome of these pregnancies. This thromboxane dominance can be eliminated with aspirin.