Risk factors for coronary artery disease in patients with systemic lupus erythematosus

Malignancy and systemic lupus erythematosus

The association of malignancy with systemic lupus erythematosus (SLE) has been investigated for years. The findings of cohort studies lend support for an increased risk of malignancy in SLE but are difficult to interpret definitively. In addition, several cohort studies have suggested an increased risk of non-Hodgkin's lymphoma but with imprecise estimation. There is inadequate evidence for any conclusions about the risk of solid tumors in these patients. A multicenter international research effort is in progress to elucidate these issues and to establish the role of exposures such as cytotoxic or immunomodulatory therapy. The recommendations advocated for cancer screening policies and for minimizing known risk factors for cancer in the general population should not be neglected in persons with SLE.

Lipopolysaccharide down regulates both scavenger receptor B1 and ATP binding cassette transporter A1 in RAW cells

Lipopolysaccharide (LPS) has recently been shown to facilitate macrophage foam cell formation and has been suggested to be a proatherogenic factor. The mechanism of LPS induced cholesterol accumulation, however, is unclear. In this report, using the macrophage-like RAW 264.7 cell line, we provide experimental evidence that LPS's proatherogenic effects may at least in part reflect altered cholesterol metabolism. Data presented demonstrate that in a dose-dependent manner, LPS is able to down regulate the mRNA expression of the two primary high-density lipoprotein (HDL) receptors, scavenger receptor B1 (SR-B1) and ATP binding cassette A1 (ABCA1), with a 50% inhibitory concentration of less than 0.2 ng/ml, as well as to decrease SR-B1 protein expression by 80%. We also found that LPS treatment resulted in a significant decrease (to 20% of the control level) of the specific (125)I-HDL binding as well as in 50% inhibition of the HDL-mediated cholesterol efflux compared to untreated cells. In addition, we compared the potencies of various modified LPS preparations and demonstrated that the phosphorylated lipid A portion of LPS, which is highly conserved among gram-negative microorganisms, including Chlamydia, is primarily responsible for the effects of LPS on SR-B1 and ABCA1 expression. Inhibitors of NF-kappaB activation were observed to efficiently block the suppressive effect of LPS on SR-B1 and ABCA1, suggesting a mechanism involving NF-kappaB. These data indicate that the LPS effects on cholesterol metabolism may contribute to the proatherogenic properties of LPS.

How to manage patients with cardiopulmonary disease?

Systemic lupus erythematosus (SLE) is a connective tissue disease characterized by the formation of autoantibodies and immune complexes. The heart and lungs are among the organ systems commonly affected in SLE. Pericarditis, premature coronary atherosclerosis, pleuritis and pulmonary infections are the most prevalent cardiopulmonary manifestations. Other rare associations include myocarditis, coronary arteritis, acute lupus pneumonitis/pulmonary haemorrhage, acute reversible hypoxaemia and 'shrinking lung' syndrome. Current imaging modalities may provide earlier detection of subclinical disease, which may aid in preventing these potentially fatal complications. The response to treatment varies, depending on the presentation of disease. In this chapter we address the frequency, diagnosis and monitoring, and treatment regimens of cardiac and pulmonary involvement in patients with SLE.

Can morbidity and mortality of SLE be improved?

Systemic lupus erythematosus (SLE) is the second most common autoimmune disorder (after thyroid disease) in women of childbearing age. Lupus is increasingly being recognized throughout the world's population. The incidence and prevalence of SLE varies among racial and ethnic groups. Lupus patient survival has significantly improved over the past five decades, but a three- to fivefold increased risk of death remains compared with the general population. As lupus patients survive longer, these individuals face a range of complications from the disease itself or consequent to its treatment. Emerging data from epidemiological studies underscore the importance of incorporating race and ethnicity in understanding the risk factors leading to the significant burden of mortality and morbidity associated with this disease. This chapter describes the epidemiology of lupus with a focus on racial and ethnic differences, reviews the mortality associated with the disease, discusses selected complications associated with morbidity related to the disease and highlights areas where we can improve mortality and morbidity.

Reproductive health in SLE

Oral contraceptives containing oestrogens and hormone replacement therapy are generally not prescribed for women with systemic lupus erythematosus (SLE). The concern regarding oestrogens is based on the greater incidence of SLE in women, abnormalities of oestrogen metabolism, murine models of lupus, several anecdotes of patients having disease flares while receiving hormones, and one retrospective study in patients with pre-existing renal disease. For healthy women and those with SLE, there are clinical settings in which exogenous oestrogens provide benefit. For pre-menopausal women, these include provision of safe and effective birth control, protection against bone loss, and the consideration of oral contraceptives to preserve fertility in patients taking cyclophosphamide. For post-menopausal women, these include treatment of hot flushes and vaginal dryness, prevention of osteoporosis and, more controversial, prevention of atherosclerosis. Other exogenous hormones (clomiphene citrate, gonadotropins, gonadotropin-releasing hormones) may be used to elevate levels of endogenous oestrogen and stimulate ovulation in patients with diminished fertility. This chapter focuses on three broad categories: birth control, assisted reproduction and hormone replacement.

Atherosclerosis and connective tissue diseases

Large increases in mortality related to premature atherosclerosis with coronary artery disease and stroke have been reported in patients with systemic lupus erythematosus (SLE), antiphospholipid syndrome (APLS), or rheumatoid arthritis (RA). Studies found relative risks of 5 for myocardial infarction, 6 to 10 for stroke in SLE patients, and 3.6 for cardiovascular deaths in RA patients. The main risk factors for atherosclerosis included not only the classic factors identified in epidemiological studies such as the Framingham study (advanced age, high cholesterol levels, hypertension, diabetes mellitus, and obesity), but also prolonged glucocorticoid therapy, long duration of SLE, postmenopausal status, and heart failure. SLE per se is an independent risk factor. The current pathogenic hypothesis for atherosclerosis involves an inflammatory response (erythrocyte sedimentation rate, C-reactive protein, and fibrin), autoantibodies, immune complexes (containing antibodies to phospholipids, to oxidized LDLs, and to endothelial cells), cytokine-producing activated T cells, and bacterial or viral infections responsible for an immune response against heat shock proteins (endogenous HSP60 and its equivalent, bacterial HSP65). Early risk factor intervention and effective control of inflammation should be incorporated into the management of connective tissue disease with the goal of protecting patients against atherosclerosis.

Traditional Framingham risk factors fail to fully account for accelerated atherosclerosis in systemic lupus erythematosus

OBJECTIVE

The frequency of coronary heart disease (CHD) and stroke are increased in systemic lupus erythematosus (SLE), but the extent of the increase is uncertain. We sought to determine to what extent the increase could not be explained by common risk factors.

METHODS

The participants at two SLE registries were assessed retrospectively for the baseline level of the Framingham study risk factors and for the presence of vascular outcomes: nonfatal myocardial infarction (MI), death due to CHD, overall CHD (nonfatal MI, death due to CHD, angina pectoris, and congestive heart failure due to CHD), and stroke. For each patient, the probability of the given outcome was estimated based on the individual's risk profile and the Framingham multiple logistic regression model, corrected for observed followup. Ninety-five percent confidence intervals (95% CIs) were estimated by bootstrap techniques.

RESULTS

Of 296 SLE patients, 33 with a vascular event prior to baseline were excluded. Of the 263 remaining patients, 34 had CHD events (17 nonfatal MIs, 12 CHD deaths) and 16 had strokes over a mean followup period of 8.6 years. After controlling for common risk factors at baseline, the increase in relative risk for these outcomes was 10.1 for nonfatal MI (95% CI 5.8-15.6), 17.0 for death due to CHD (95% CI 8.1-29.7), 7.5 for overall CHD (95% CI 5.1-10.4), and 7.9 for stroke (95% CI 4.0-13.6).

CONCLUSION

There is a substantial and statistically significant increase in CHD and stroke in SLE that cannot be fully explained by traditional Framingham risk factors alone.

The role of technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography (SPECT) in the detection of cardiovascular involvement in systemic lupus erythematosus patients with non-specific chest complaints

OBJECTIVES

Systemic lupus erythematosus (SLE) can affect multiple organs. Coronary artery disease has received increasing recognition as a major cause of morbidity and mortality in SLE in recent years. The purpose of this study was to evaluate the utility of technetium-99m sestamibi single-photon emission computed tomography ((99m)Tc-sestamibi SPECT) in the detection of cardiovascular involvement in SLE patients with non-specific clinical chest symptoms such as chest discomfort and/or dyspnoea and/or occasional palpitation.

METHODS

Thirty-three SLE female patients (age range: 22-45 yr) with non-specific complaints such as chest discomfort and/or dyspnoea and/or occasional palpitation were investigated using a (99m)Tc-sestamibi myocardial perfusion SPECT scan at rest and after dipyridamole infusion in a stress study. The age- and sex-matched healthy group (24 cases) and SLE patients without any cardiovascular symptoms/signs (28 cases) were also included as controls in this study. The results of the uptake pattern of (99m)Tc-sestamibi were classified into four types including normal, persistent perfusion defect, reversible perfusion defect and reverse redistribution.

RESULTS

Perfusion abnormalities were detected in 27 cases (seven patients had persistent perfusion defects, 15 patients had reversible perfusion defects, one patient had both persistent and reversible perfusion defects, two patients showed a reverse redistribution pattern and two patients had both reversible perfusion defects and a reverse redistribution pattern). The results of the SPECT in the healthy group were all normal. However, perfusion abnormalities were detected in 12 cases in the group of asymptomatic SLE patients.

CONCLUSIONS

(99m)Tc-sestamibi myocardial perfusion SPECT is a useful non-invasive imaging modality to detect cardiovascular involvement in SLE patients with non-specific clinical complaints of heart disease.

Accelerated atherosclerosis in systemic lupus erythematosus: implications for patient management

One of the most compelling clinical challenges in the management of systemic lupus erythematosus (SLE) is the high incidence of atherosclerotic cardiovascular disease (ASCVD). Potential mechanisms for accelerated atherosclerosis in SLE include chronic inflammation, excess of traditional risk factors, and corticosteroid therapy. Given the high prevalence of atherosclerosis in SLE patients relative to young women in the general population, we propose that the presence of SLE constitutes a sufficiently potent risk factor for ASCVD to warrant more aggressive goals for risk factor reduction and strategies to reduce inflammation.

Unusual coronary artery aneurysm and acute myocardial infarction in a middle-aged man with systemic lupus erythematosus

A 55-year-old man developed acute myocardial infarction (AMI) related to a large coronary artery aneurysm and a distal coronary stenotic lesion after steroid therapy for systemic lupus erythematosus (SLE). Only 13 SLE patients with AMI caused by coronary artery aneurysms have been reported, 11 of whom were young or middle-aged women and the 2 remaining were young men. This is the first report of a middle-aged man with multiple coronary lesions.

Accelerated atheroma, antiphospholipid antibodies, and the antiphospholipid syndrome

Indirect data coming from animal studies and in vitro observations support the contention that the mere presence of antiphospholipid antibodies may be sufficient to increase atheroma development, regardless of other predisposing factors. It seems that humoral and cellular immune responses to beta 2-glycoprotein I can play an important role in mediating the increased propensity to atherosclerosis.

Comorbidity in rheumatoid arthritis

It is increasingly clear that coexistent disease plays a pivotal role in RA outcome and that efforts aimed at specifically addressing these comorbidities need to be aggressively sought, investigated, and implemented once proven effective. RA-associated costs are currently increasing at twice the rate of the medical care index. Comorbidity in the setting of RA independently predicts disease-associated disability (a major cost component) and mortality, underscoring the need for a more comprehensive approach to RA, one that adequately addresses disease-specific comorbidities. At present, many primary and secondary preventative measures (Table 1) for RA-specific comorbidities remain largely unproved and require rigorous investigation in a randomized prospective fashion. Despite this ongoing need, advances are being made in our understanding of the underlying pathogenesis of these comorbid conditions and their relation with RA. This improved understanding should translate into further effective interventions. Bisphosphonates, for instance, have been shown to be effective in the prevention of GIOP and associated fractures. The past several years have seen other exciting therapeutic advances in RA. DMARD combinations have been shown to be more effective and no more toxic than MTX monotherapy. In addition to the recent release of COX-2 NSAIDs, three new disease-modifying agents (leflunomide, etanercept, and infliximab) have been added to the therapeutic armamentarium; these are options that have markedly changed the treatment landscape in RA. Although these important advances have generated much deserved optimism, the precise effect that these agents may have on RA-specific comorbidity remains to be seen. The next decade should prove to be an exciting time in RA management. Better identification, understanding, and management of RA comorbidities have great potential to improve quality of life and survival among our patients with RA.

Systemic lupus erythematosus in three ethnic groups. VII [correction of VIII]. Predictors of early mortality in the LUMINA cohort. LUMINA Study Group

OBJECTIVE

To determine the features associated with mortality in a multiethnic US cohort of patients with systemic lupus erythematosus (SLE) within 5 years of study onset.

METHODS

Socioeconomic and demographic features (age, gender, ethnicity, marital status, education, occupation, poverty, and health-related behaviors [drinking, smoking, exercising]), clinical and immunologic features (disease duration, disease onset type, disease activity according to the Systemic Lupus Activity Measure [SLAM], disease damage according to the Systemic Lupus International Collaborating Clinics [SLICC] Damage Index [SDI], number of American College of Rheumatology criteria at diagnosis, organ system manifestations, fatigue and pain ratings, and medication usage and autoantibodies), immunogenetic features (HLA class II genotypes), and behavioral and psychosocial features (social support, illness-related behaviors, and helplessness), as obtained at enrollment into the study, were compared between survivors and deceased patients. Logistic regression analysis was used to determine significant independent risk factors for mortality.

RESULTS

Within 5 years of study onset, 34 of 288 patients have died. Fourteen deaths could be directly attributed to SLE and 11 to infections. In 1 patient the cause of death could not be determined. In the remaining 8 patients the cause of death was neither infectious nor disease-related. There were 10 deaths among Hispanics, 18 among African Americans, and 6 among Caucasians (P < 0.05). Variables associated with mortality in the univariable analyses included poverty, less than full-time employment, difficulty in accessing health care, shorter disease duration, cardiovascular and renal involvement, higher serum creatinine levels and lower hematocrit values, higher SLAM and SDI scores, lower use of antimalarial drugs, and higher use of (some) immunosuppressants. Specific autoantibodies and class II HLA genotypes were not associated with mortality. Poverty and higher baseline SLAM and SDI scores were independently associated with mortality in the multivariable analyses.

CONCLUSIONS

Disease activity, disease damage, and poverty appear to be the most important determinants of mortality in this multiethnic US cohort of SLE patients. These results have applicability to the management of patients with SLE, a disease that more severely affects disadvantaged minority population groups.

Vascular stiffness in women with systemic lupus erythematosus

Large-vessel manifestations of systemic lupus erythematosus (SLE), a multisystem disease characterized by disturbances in the immune system, include higher than expected rates of hypertension and cardiovascular disease. Reductions in the elasticity of central arteries may act as a marker of early changes that predispose to the development of major vascular disease. This study evaluated risk factors associated with aortic stiffness measured by pulse wave velocity (PWV) in women with SLE. We expected SLE-specific factors, especially variables indicative of inflammation and active disease, to be associated with increasing PWV. The study population included 220 women currently enrolled in the Pittsburgh Lupus

REGISTRY

All risk factor data were collected on the day of the ultrasound examinations. PWV waveforms were collected from the right carotid and femoral arteries by Doppler probes. The mean age of the women was 45.5+/-10.8 years, the median SLE disease duration approximated 9 years, and the mean PWV was 6.1+/-1.7 m/s. Multiple regression models were stratified by menopausal status. Among postmenopausal women, PWV risk factors were primarily traditional factors and included age, systolic blood pressure, family history of vascular disease, carotid plaque, creatinine, obesity, glucose, white cell count, and cumulative SLE organ damage. Among premenopausal women, PWV risk factors consisted of a mix of SLE-related and traditional variables and included higher C3 levels, presence of ds-DNA antibodies, nonuse of hydroxychloroquine, lower leukocyte count, higher mean arterial pressure, and carotid plaque. SLE-specific variables appeared to be associated with increases in aortic PWV, indicating central artery stiffening. This was seen most clearly among premenopausal women. This finding may partially explain the higher rates of cardiovascular disease and hypertension observed in young women with SLE.

Vascular events in hypertensive patients with systemic lupus erythematosus

Our purpose was to examine prospectively the relationship between systemic hypertension and vascular events in patients with SLE. SLE patients followed in the University of Toronto Lupus Clinic presenting between 1980 and 1988 and within one year of their diagnosis of SLE were identified. Standard definitions were used for hypertension and for all vascular events (MI, angina, CVA, PVD). The presence of traditional CAD risk factors, along with disease- and therapy-related risk factors for the development of vascular disease, were compared in the hypertensive and normotensive group. A multivariate logistic regression was performed to determine the best predictor of a vascular event. One hundred and fifty patients were identified in our inception cohort [75 hypertensive (50%) and 75 (50%) normotensive]. Seventeen hypertensive patients (22.7%) had at least one vascular event as compared to six (8.0%) normotensive patients (p = 0.022). The vascular events included 7 with CAD, 5 with CVA, and 5 with PVD in the hypertensive group while in the normotensive group 3 patients developed CAD, 2 CVA and 1 PVD. Fifteen deaths were recorded in the hypertensive group as compared to eight deaths in the non-hypertensive groups (P = 0.09). The groups were comparable with respect to associated risk factors, except for higher frequency of hypercholesterolemia (P = 0.003), azotemia (P = 0.001) and corticosteroid use (P = 0.038) in the hypertension group. In a multivariate analysis the best predictor of a vascular event was hypercholesterolemia (OR 6.9, 95% CI 2.4-24.8, P < 0.001). We conclude that systemic hypertension is associated with an increased frequency of vascular events in SLE. This is best explained by its association with hypercholesterolemia.

Prevalence and relation to risk factors of carotid atherosclerosis and left ventricular hypertrophy in systemic lupus erythematosus and antiphospholipid antibody syndrome

The prevalence of preclinical cardiovascular disease was determined in women with systemic lupus erythematosus (SLE) and control subjects matched for traditional risk factors. Compared with control subjects, patients with SLE had a higher prevalence of carotid atherosclerosis (41% vs 9%, p < 0.005) and left ventricular hypertrophy (32% vs 5%, p < 0.005), supporting the possibility that chronic inflammation predisposes to premature cardiovascular disease in SLE.

Preliminary guidelines for the evaluation and management of dyslipidemia in adults infected with human immunodeficiency virus and receiving antiretroviral therapy: Recommendations of the Adult AIDS Clinical Trial Group Cardiovascular Disease Focus Group

Dyslipidemia is a prevalent condition that affects patients infected with human immunodeficiency virus (HIV) who are receiving antiretroviral therapy. These preliminary recommendations summarize the current understanding in this area and propose guidelines for management. Existing guidelines for the management of dyslipidemia in the general population formed the general basis for our recommendations. Data on the prevalence and treatment of dyslipidemia of HIV-infected patients, implications of treatment-related dyslipidemia in other chronically ill populations, and pharmacokinetic profiles for the available hypolipidemic agents in non-HIV populations were considered. Although the implications of dyslipidemia in this population are not fully known, the frequency, type, and magnitude of lipid alterations in HIV-infected people are expected to result in increased cardiovascular morbidity. We propose that these patients undergo evaluation and treatment on the basis of existing guidelines for dyslipidemia, with the caveat that avoidance of interactions with antiretroviral agents is paramount.

A pilot study on the effects of exercise in patients with systemic lupus erythematosus

OBJECTIVE

A pilot study was designed to assess the efficacy and safety of different exercise therapies on patient-reported fatigue and functional status.

METHODS

Ten patients with systemic lupus erythematosus (SLE) were randomly placed in either an aerobic exercise group (group 1: n = 5) or a range of motion/muscle strengthening (ROM/MS) exercise group (group 2: n = 5). Outcome measures assessed at baseline and the end of the study were fatigue, functional status, disease activity, cardiovascular fitness, isometric strength, bone mineral density (BMD) of the lumbar spine and femoral neck, and parathyroid hormone and osteocalcin as representative bone biochemical markers for bone resorption and bone formation, respectively.

RESULTS

Both aerobic and ROM/MS types of exercise were safe and did not worsen SLE disease activity. Patients in both exercise groups showed some improvement in fatigue, functional status, cardiovascular fitness, and muscle strength. Both groups showed increased bone turnover, but BMD was unchanged. Eighty percent of the patients met the compliance standard for the study.

CONCLUSIONS

This pilot study shows the feasibility of exercise for SLE patients. The potential value of this approach shows promise in the routine management of these patients.

Cardiovascular and cerebrovascular morbidity and mortality among women with end-stage renal disease attributable to lupus nephritis

Cardiovascular and cerebrovascular diseases are common causes of morbidity and mortality in women with systemic lupus erythematosus (SLE) and are also common in patients with end-stage renal disease (ESRD). To determine whether women with ESRD caused by lupus nephritis are at greater risk for morbidity from these conditions than women with other causes of ESRD, data from the US Renal Data System were used to compare incidence rates of hospitalizations for acute myocardial infarction and cerebrovascular accident between women with ESRD caused by lupus nephritis and women with ESRD from other causes. The age- and race-adjusted incidences of hospitalizations for acute myocardial infarction during dialysis were 16.4 hospitalizations/1,000 patient-years among women with ESRD caused by lupus nephritis and 17.3 hospitalizations/1,000 patient-years among women in the comparison group (adjusted hazard ratio, 0.80; 95% confidence interval [CI], 0.58 to 1.08; P = 0.14). Adjusted incidence rates for acute myocardial infarction after renal transplantation also did not differ between these groups. Adjusted incidence rates for hospitalizations for cerebrovascular accident during dialysis were 18.5 hospitalizations/1,000 patient-years among women with ESRD caused by lupus nephritis and 19.2 hospitalizations/1,000 patient-years among women in the comparison group (adjusted hazard ratio, 0.87; 95% CI, 0.66 to 1.14; P = 0.30); incidence rates after transplantation also did not differ between groups. Risks for death from cardiovascular or cerebrovascular diseases also were not increased among women with ESRD caused by lupus nephritis. Sepsis was the most common cause of death in this group. Morbidity and mortality from acute myocardial infarction and cerebrovascular accident were substantially greater among women with ESRD caused by diabetes mellitus. Although morbidity and mortality from cardiovascular and cerebrovascular diseases are common among women with SLE, risks for these outcomes are not greater among women with ESRD caused by lupus nephritis than among other women without diabetes with ESRD.

Detection of coronary artery disease and the role of traditional risk factors in the Hopkins Lupus Cohort

Coronary artery disease (CAD) is a major cause of morbidity and mortality in SLE, including the Hopkins Lupus Cohort. Currently, 9% of the cohort have had clinical evidence (angina or myocardial infarction) of CAD. In our initial prospective study we found that duration of prednisone, hypertension, hyperlipidemia and obesity were risk factors for later CAD. We can now extend that list to include age, male sex, elevated homocysteine, renal insufficiency and antiphospholipid antibodies. Many of the risk factors are amenable to intervention, but the timing of intervention, and the effectiveness of intervention, must be determined.

Vascular imaging: changing the face of cardiovascular research

Patients with systemic lupus erythematosus (SLE) are at significant risk for premature cardiovascular disease, now a leading cause of death in this population. Most previous studies have used an overt clinical event to identify cardiovascular disease, likely underestimating the actual prevalence in these patients. Although the rates of myocardial infarction in SLE are high, the actual number of coronary events is low, precluding large clinical trials using a coronary event as the sole outcome. The ability to measure atherosclerosis, a known determinant of coronary heart disease, provides investigators with a desirable surrogate for the clinical cardiac event. With the advent of sensitive imaging techniques to identify subclinical atherosclerosis, we are now better equipped to determine the true prevalence and mechanisms of vascular disease in SLE. In this review, we will discuss several vascular imaging techniques and the current trend away from measuring flow-limiting vessel stenosis toward measuring earlier structural and functional aspects of the vascular system.

Epidemiology of cardiovascular disease in systemic lupus erythematosus

Awareness of the impact of cardiovascular disease on the late morbidity and mortality in patients with Systemic Lupus Erythematosus (SLE) is increasing. Clinical events secondary to accelerated atherosclerosis have been documented in lupus cohorts across the globe. We review the history and epidemiology of cardiovascular disease in patients with SLE.

Accelerated atheroma in lupus--background

Observational cohort studies in SLE have led to the description of accelerated atherosclerosis as an important cause of mortality and morbidity in this disease. The clinical observation of coronary artery disease occurring in premenopausal females with SLE gave rise to the concept of the bimodal mortality pattern. This pattern was confirmed in autopsy and epidemiological studies. These studies identified hypercholesterolemia and particularly its persistence in the first three years of disease, hypertension, and lupus itself as important risk factors for the development of accelerated atherosclerosis in these patients. It also became evident that corticosteroid therapy plays an important role in the elevation of plasma lipids while antimalarials resulted in a reduction of plasma cholesterol, LDL, and VLDL, especially in steroid-induced hyperlipidemia. Studies of clinical outcomes for atherosclerotic disease (angina, myocardial infarction) have shown a prevalence of 6-12% in a number of SLE cohorts. However, more sensitive investigations including myocardial perfusion imaging and carotid ultrasound have demonstrated a prevalence of atherosclerotic disease in 40% of patients studied. Further studies of SLE disease process, including immunological factors, may more clearly define the pathogenesis of accelerated atherosclerosis in patients with SLE, and may help elucidate mechanisms of atherosclerosis in the general population.

Lipids, cardiovascular disease and atherosclerosis in systemic lupus erythematosus

Systemic lupus erythematosus is commonly associated with early onset cardiovascular disease and is often associated with hyperlipidaemia. This review examines the evidence for an increased prevalence of both CHD and hyperlipidaemia in SLE and mechanisms by which autoimmunity in SLE could accelerate the progression of atheroma. It postulates how lipid lowering therapies used in cardiological disease might help reduce the incidence of CHD in SLE.

How accelerated atherosclerosis in SLE has changed our management of the disorder

Basic science insights along with the assessment of risk factors so clearly documented by the Canadian and Hopkins cohorts in earlier papers of this special issue have clearly led to a change in the way rheumatologists manage SLE. This review will highlight specific ways it should alter our day to day treatment of lupus patients.

Menopause, oestrogens and arthritis

The menopause coincides with the appearance of many of the common arthritic conditions and with the lessening of severity of others such as SLE. The hormonal changes that occur may modulate these diseases. Thus, hormonal manipulation may have either beneficial or detrimental effects on the incidence and activity of a number of common joint diseases. We review the evidence regarding the effect of the menopause and oestrogen replacement therapy on the pathogenesis, incidence and prevalence and disease activity of osteoarthritis, rheumatoid arthritis, systemic lupus erythematosus and carpal tunnel syndrome.

Premature atherosclerosis in systemic lupus erythematosus

SLE is a multifaceted disease; over the past 20 years, as survival has improved dramatically, new challenges have emerged. It is now clear from the results of studies at several centers that SLE is associated with at least a fivefold increased risk of CAD, which is accelerated at its onset and seems to abolish a female premenopausal protection against CAD. Several groups have also found by various techniques that subclinical disease occurs at a frequency of about 35% to 40%. The pathogenesis of atherosclerosis in this context seems to be a complex interaction of factors associated with the disease, its therapy, and traditional risk factors. Indeed, experimental models suggest a synergy of these different dimensions in plaque formation. Hypercholesterolemia has been identified as predictive of both future CAD events and sub-clinical disease. This is mainly the case in those patients in whom hypercholesterolemia is a sustained phenomenon. In addition, SLE itself seems to be a strong risk factor for CAD over and above the effects of the known traditional CAD risk factors. There is a lot that is still unknown about the pathogenesis of CAD in SLE. Current knowledge is sufficient to justify the belief that an aggressive approach to management of traditional CAD risk factors in patients with SLE is likely to have a major impact on morbidity and mortality in this population. For this to happen, patients must be educated about this issue and be encouraged to play an active role in lifestyle modifications. In addition, clinicians who care for patients with SLE need to assume a primary role in screening and coordinating the management of CAD risk factors in these high-risk patients.

Hopkins Lupus Cohort. 1999 update

The Hopkins Lupus Cohort is a decade-long prospective study, now numbering 800 patients with systemic lupus erythematosus. In this article, predictors of disease activity, disease damage (including accelerated atherosclerosis and antiphospholipid antibody syndrome) and health status are reviewed.

Overexpression of secretory phospholipase A(2) causes rapid catabolism and altered tissue uptake of high density lipoprotein cholesteryl ester and apolipoprotein A-I

Plasma levels of high density lipoprotein (HDL) cholesterol and its major protein component apolipoprotein (apo) A-I are significantly reduced in both acute and chronic inflammatory conditions, but the basis for this phenomenon is not well understood. We hypothesized that secretory phospholipase A(2) (sPLA(2)), an acute phase protein that has been found in association with HDL, promotes HDL catabolism. A series of HDL metabolic studies were performed in transgenic mice that specifically overexpress human sPLA(2) but have no evidence of local or systemic inflammation. We found that HDL isolated from these mice have a significantly lower phospholipid and cholesteryl ester and significantly greater triglyceride content. The fractional catabolic rate (FCR) of (125)I-HDL was significantly faster in sPLA(2) transgenic mice (4.08 +/- 0.01 pools/day) compared with control wild-type littermates (2.16 +/- 0.48 pools/day). (125)I-HDL isolated from sPLA(2) transgenic mice was catabolized significantly faster than (131)I-HDL isolated from wild-type mice after injection in wild-type mice (p < 0.001). Injection of (125)I-tyramine-cellobiose-HDL demonstrated significantly greater degradation of HDL apolipoproteins in the kidneys of sPLA(2) transgenic mice compared with control mice (p < 0.05). The fractional catabolic rate of [(3)H]cholesteryl ether HDL was significantly faster in sPLA(2)-overexpressing mice (6.48 +/- 0.24 pools/day) compared with controls (4.80 +/- 0.72 pools/day). Uptake of [(3)H] cholesteryl ether into the livers and adrenals of sPLA(2) transgenic mice was significantly enhanced compared with control mice. In summary, these data demonstrate that overexpression of sPLA(2) alone in the absence of inflammation causes profound alterations of HDL metabolism in vivo and are consistent with the hypothesis that sPLA(2) may promote HDL catabolism in acute and chronic inflammatory conditions.

Atherosclerosis and systemic lupus erythematosus

The description of late-stage mortality and morbidity has been an important contribution to the understanding of systemic lupus erythematosus (SLE) in the past decade. Among the major factors in this clinical spectrum of SLE is the development of accelerated atherosclerosis. This condition has been recognized clinically with the documentation of myocardial infarction and angina in young women with SLE. This accelerated atherosclerosis has also been recognized at postmortem examinations. The exact mechanism for accelerated atherosclerosis remains unclear. However, disease activity with its immunologic events, the anticardiolipin syndrome, and the effect of corticosteroids in promoting hyperlipidemia contribute to its development. It appears that SLE may be a risk factor, in addition to the usual risk factors for the development of atherosclerosis. It has recently been shown that antimalarials may prevent some of the hyperlipidemia caused by corticosteroids. As evidence for the presence of subclinical atherosclerosis in these patients is accumulating, earlier diagnosis and treatment of events may be possible, and preventive measures may be instituted earlier.

Determinants of enhanced thromboxane biosynthesis in patients with systemic lupus erythematosus

OBJECTIVE

To evaluate the rate of thromboxane biosynthesis in patients with systemic lupus erythematosus (SLE), exploring the interplay between antiphospholipid antibodies (aPL) and 2 markers of endothelial perturbation: thrombin generation and platelet activation.

METHODS

A comparison of 11-dehydrothromboxane B2 (TXB2) excretion, which is a marker of in vivo platelet activation, aPL, von Willebrand factor (vWF) and tissue plasminogen activator (tPA), which are 2 circulating markers of endothelial perturbation, and plasma levels of the prothrombin fragment F1+2, which is a marker of thrombin generation, was performed in 40 SLE patients and 40 healthy subjects. Thromboxane metabolite excretion was also measured in 8 SLE patients before and after treatment with low-dose aspirin.

RESULTS

SLE patients had significantly higher 11-dehydro-TXB2 excretion, plasma F1+2, vWF, and tPA levels than controls. A statistically significant correlation was found between plasma levels of vWF and tPA and excretion of thromboxane metabolite. Moreover, significantly higher 11-dehydro-TXB2 was found in patients with aPL positivity and endothelial perturbation. Low-dose aspirin suppressed 11-dehydro-TXB2 by 80%, suggesting a predominant platelet source of enhanced thromboxane biosynthesis. After a median followup of 48 months, all SLE patients who experienced major cardiovascular events had thromboxane metabolite excretion, aPL positivity, and signs of endothelial perturbation.

CONCLUSION

We have characterized a sensitive marker of platelet activation, which is abnormal in SLE patients who were positive for aPL and endothelial perturbation. This analytical approach may help identify those patients at increased risk of thrombosis as potential candidates for antiplatelet therapy.

Women's health

Symptoms reliably attributable to menopause are vasomotor symptoms and vaginal dryness. Other symptoms are not directly related to the menopause. HRT or ERT are effective in providing symptom relief and preventing disease prevalent in postmenopausal women. HRT or ERT is beneficial in women with RA. Little data concerns safety in SLE patients, but there are theoretical advantages to using HRT or ERT in women with SLE and two studies that indicate it is safe. Other forms of treatment are available to women who cannot or will not use HRT or ERT.

Management of lipid disorders

ASCVD is common in patients with rheumatologic disorders. Reduction of LDL cholesterol and treatment of lipid disorders is proved to reduce the risk of ASCVD and its associated clinical events. Therefore, plasma lipids should be obtained in all patients with rheumatologic disorders and lipid disorders should be aggressively treated in an attempt to reduce cardiovascular risk. The clinical approach is similar to other patients, but care should be taken to avoid side effects and drug-drug interactions, which may be somewhat more likely to occur in patients with rheumatologic disorders.

Antibodies against lysophosphatidylcholine and oxidized LDL in patients with SLE

Lysophosphatidylcholine (LPC) is present in oxidized low density lipoprotein (oxLDL), which is implicated in atherosclerosis. Antibodies to cardiolipin (aCL) and oxLDL (aoxLDL) have been shown to crossreact. LPC is formed by hydrolysis of phosphatidylcholine (PC) in LDL and cell membranes, induced by phospholipase A2 or by oxidation. We here demonstrate the presence of enhanced antibody levels to LPC in 184 patients with SLE as compared to 85 healthy, age-matched controls. The antibody reactivity to LPC was not specifically related to oxidation of the fatty acid moiety in LPC, since LPC containing only the saturated fatty acid palmitic acid showed equivalent antibody levels as LPC containing unsaturated fatty acids. aPC were significantly lower as compared to aLPC, indicating that hydrolysis of PC at the sn-2 position increases the antigenic potential of the molecule. Beta-glycoprotein 1 was a cofactor for aCL, but not for aoxLDL or aLPC, and the antigenicity of these compounds is therefore not directly related to beta2GP1. There was a close correlation between aoxLDL, aCL and aLPC and both LPC and oxLDL competitively inhibited aCL-binding to CL. LPC, oxLDL and CL thus display a common antigenic site, which could be formed by removal of a fatty acid at the sn-2 position, possibly due to the activity to phospholipase A2 and/or oxidation. This study indicates the potential role of LDL-oxidation and phospholipase A2 in SLE.

Antibodies to adult human endothelial cells cross-react with oxidized low-density lipoprotein and beta 2-glycoprotein I (beta 2-GPI) in systemic lupus erythematosus

Cardiovascular manifestations are common in systemic lupus erythematosus (SLE). Oxidized low-density lipoprotein (oxLDL) is implicated in cardiovascular disease, especially atherosclerosis, and cross-reacts with antibodies to cardiolipin (aCL). beta 2-GPI is a plasma protein participating in the coagulating cascade, and is also cofactor for aCL, and some aCL have been shown to be directed against beta 2-GPI and/or complexes between beta 2-GPI and phospholipids. Lysophosphatidylcholine (LPC) is a phospholipid present both in oxLDL and in damaged endothelium, and we recently showed that LPC is involved in the antigenicity of oxLDL. Antibodies to endothelial cells (aEC) correlate with diseases activity in SLE and vasculitis, and we recently showed that aEC are enhanced in cardiovascular disease such as borderline hypertension and early atherosclerosis. aEC were determined using EC from adult V. Saphena Magna. Antibody levels were determined by ELISA. aEC of IgG type were enhanced in 184 patients with SLE compared with 85 healthy controls. There was a close correlation between aoxLDL, aCL, aLPC, a beta 2-GPI and aEC. Binding of sera to EC was competitively inhibited by beta 2-GPI, LPC and oxLDL. Taken together, the data indicate that EC share antigenic epitopes with beta 2-GPI and with oxLDL, especially LPC. Phospholipids in EC membranes may thus be antigenic epitopes. beta 2-GPI may bind to these phospholipids, and become an autoantigen. LPC is formed by oxidation of phospholipids and/or proinflammatory factors leading to activation of phospholipase A2, and the findings indicate the potential role of both lipid oxidation and phospholipase A2 in SLE.

Myocardial infarction in patients with systemic lupus erythematosus with normal findings from coronary arteriography and without coronary vasculitis--case reports

The authors present the cases of two young patients, a man and a woman, who presented with myocardial infarction, in the absence of ischemic heart disease or stenosis of the coronary arteries. The woman was known to have systemic lupus erythematosus (SLE) for the past 3 years (the immunoglobulin M [IgM] anticardiolipins antibodies were positive), without a history of coronary risk factors. Suddenly she presented with acute chest pain on rest that lasted 4 hours and culminated in anterior wall myocardial infarction. She was admitted to the coronary care unit, where no thrombolysis was given. She did not have echocardiographic evidence of Libman-Sacks endocarditis, but myocardial infarction was evident at the electrocardiogram (ECG). The young man had SLE (the IgM anticardiolipins were absent, but he was positive for lupus anticoagulant antibodies), he was hyperlipidemic, was a moderate smoker and moderately obese, and had no history of ischemic heart disease. He suddenly presented with an acute myocardial infarction documented by ECG, enzymes, and gammagraphy. In both patients, coronary angiography findings were normal and myocardial biopsy did not show evidence of arteritis. The relevance of these cases is the rare association of ischemic heart disease in SLE, with normal coronary arteries and without evidence of arteritis or verrucous endocarditis.

Premature morbidity from cardiovascular and cerebrovascular diseases in women with systemic lupus erythematosus

OBJECTIVE

To determine rates of morbidity due to cardiovascular and cerebrovascular diseases among women with systemic lupus erythematosus (SLE).

METHODS

I used the California Hospital Discharge Database, which contains information on all discharges from acute care hospitals in California, to identify women with SLE who had been hospitalized for treatment of either acute myocardial infarction (AMI), congestive heart failure (CHF), or cerebrovascular accident (CVA) from 1991 to 1994. I compared the proportions of hospitalizations for each cause among women with SLE with those in a group of women without SLE, for 3 age strata (18-44 years, 45-64 years, and > or =65 years).

RESULTS

Compared with young women without SLE, young women with SLE were 2.27 times more likely to be hospitalized because of AMI (95% confidence interval [95% CI] 1.08-3.46), 3.80 times more likely to be hospitalized because of CHF (95% CI 2.41-5.19), and 2.05 times more likely to be hospitalized because of CVA (95% CI 1.17-2.93). Among middle-aged women with SLE, the frequencies of hospitalization for AMI and CVA did not differ from those of the comparison group, but the risk of hospitalization for CHF was higher (odds ratio [OR] 1.39, 95% CI 1.05-1.73). Among elderly women with SLE, the risk of hospitalization for AMI was significantly lower (OR 0.70, 95% CI 0.51-0.89), the risk of hospitalization for CHF was higher (OR 1.25, 95% CI 1.01-1.49), and the risk of hospitalization for CVA was not significantly different from those in the comparison group.

CONCLUSION

Young women with SLE are at substantially increased risk of AMI, CHF, and CVA. The relative odds of these conditions decrease with age among women with SLE.

Prevalence and risk factors of carotid plaque in women with systemic lupus erythematosus

OBJECTIVE

To determine the prevalence of carotid atherosclerosis and associated risk factors in women with systemic lupus erythematosus (SLE).

METHODS

Carotid plaque and intima-media wall thickness (IMT) were measured by B-mode ultrasound in women with SLE. Risk factors associated with carotid plaque and IMT were determined at the time of the ultrasound scan and included traditional cardiovascular risk factors, SLE-specific variables, and inflammation markers.

RESULTS

The 175 women with SLE were predominantly white (87%), with a mean age of 44.9 years (SD 11.5). Twenty-six women (15%) had a previous arterial event (10 coronary [myocardial infarction or angina], 11 cerebrovascular [stroke or transient ischemic attack], and 5 both). The mean +/- SD IMT was 0.71 +/- 0.14 mm, and 70 women (40%) had focal plaque. Variables significantly associated with focal plaque (P < 0.05) included age, duration of lupus, systolic, diastolic, and pulse pressure, body mass index, menopausal status, levels of total and low-density lipoprotein (LDL) cholesterol, fibrinogen and C-reactive protein levels, SLE-related disease damage according to the Systemic Lupus International Collaborating Clinics (SLICC) damage index (modified to exclude cardiovascular parameters), and disease activity as determined by the Systemic Lupus Activity Measure. Women with longer duration of prednisone use and a higher cumulative dose of prednisone as well as those with prior coronary events were more likely to have plaque. In logistic regression models, independent determinants of plaque (P < 0.05) were older age, higher systolic blood pressure, higher levels of LDL cholesterol, prolonged treatment with prednisone, and a previous coronary event. Older age, a previous coronary event, and elevated systolic blood pressure were independently associated with increased severity of plaque (P < 0.01). Older age, elevated pulse pressure, a previous coronary event, and a higher SLICC disease damage score were independently related to increased IMT (P < 0.05).

CONCLUSION

B-mode ultrasound provides a useful noninvasive technique to assess atherosclerosis in women with SLE who are at high risk for cardiovascular disease. Potentially modifiable risk factors were found to be associated with the vascular disease detected using this method.

Prevention and treatment of adverse effects of corticosteroids in systemic lupus erythematosus

Corticosteroid therapy has had a major impact on improvement in disease activity and long-term survival in patients with systemic lupus erythematosus (SLE). Unfortunately, the therapeutic advantages are accompanied by many manifestations of toxicity, some of which are short term and potentially reversible, while others cause chronic irreversible damage. Many of these features of toxicity have similar presentations to manifestations of SLE disease activity, and must be distinguished in the individual patient. The features of corticosteroid toxicity are reviewed in this chapter, and means of prevention and/or treatment are discussed.