Metabolic syndrome is marked by increased risk of cardiovascular diseases, so its incidence among people with lupus can indicate risk of cardiovascular disease in lupus patients.
Lack of Cardiovascular Risk Assessment in a Canadian Population of Lupus Patients
Lack of cardiovascular risk assessment in inflammatory arthritis and systemic lupus erythematosus patients at a tertiary care center.
Keeling SO, Teo M, and Fung D. (2011). Clinical Rheumatology, epub ahead of print.
What is the topic?
People with lupus have an increased risk of heart disease and stroke due to premature hardening of the arteries. This increased risk is due in part to traditional risk factors (such as diabetes, high blood pressure, and high cholesterol) and in part due to lupus-specific immune dysfunction. Further, the role that medications used to treat lupus play in prevention or induction of heart disease or stroke has not been well-characterized. Thus, it is important to actively assess and detect traditional risk factors for heart disease in people with lupus on an ongoing basis. To this end, the European League Against Rheumatism (EULAR) recommends annual risk assessment for heart disease in people with lupus.
What did the researchers hope to learn?
The researchers aimed to evaluate how effectively risk for heart disease was being assessed in a population of lupus patients being cared for in Alberta, Canada.
Who was studied?
In this study, charts from 504 patients, being cared for at nine rheumatology centers at the University of Alberta Hospital in Canada, were reviewed. Of these 504 patients, 64 (about 13%) were diagnosed as having lupus and most of them were women.
How was the study conducted?
Medical charts were reviewed for patients being cared for at nine rheumatology centers at the University of Alberta Hospital in Canada. Data in the medical charts included patient demographics, traditional heart disease risk factors, medications being taken for lupus or heart disease, history of heart disease evaluations and treatment, blood pressure, lupus disease duration, and several measurements of blood components indicative of lupus disease activity.
For purposes of this study, a diagnosis of lupus relied entirely on a rheumatologist’s assessment and was considered positive even if four of the ACR criteria for lupus were not met.
Patients with the following conditions were excluded from the study: overlap syndrome, mixed (and undifferentiated) connective tissue disease, and early, undeclared inflammatory rheumatic diseases.
What did the researchers find?
The lupus patients included in this study had an average disease duration of 10 years and an average age at diagnosis of 30. Over 90% of the lupus patients were taking anti-malarial drugs or had taken them in the past. Over half (59%) of the lupus patients were taking prednisone or had taken it in the past. Only about 6% of the lupus patients were taking non-steroidal anti-inflammatory drugs (NSAIDs) or had taken them in the past.
Charts for most of the lupus patients (over 96%) included information about blood pressure and about 39% of them were taking drugs to lower blood pressure. However, charts for most of the lupus patients did not include information about obesity, diabetes, or family history of heart disease (over 90% in each case). Charts for over half of the lupus patients did not include information about smoking or levels of fat in the blood (over 51% in each case). This was true even though the most common traditional heart disease risk factor in these patients was high blood pressure, followed by abnormal levels of fat in the blood. Information about heart disease risk factors was absent or missing to the extent that an assessment of 10-year risk of heart disease could not be calculated for all but one of the lupus patients.
What were the limitations of the study?
Limitations included the fact that the data were obtained from patient charts “retrospectively” (meaning that charts from previous patient assessments were studied), which may limit the accuracy of the information gathered. As such, it is unclear if these risk factors were being treated or detected by primary care physicians, even if the rheumatologists were not addressing them. Further, since about half of the lupus patients did not meet the ACR criteria for lupus, it is possible that some of the patients did not actually have lupus. Also, in this study, it was not possible to differentiate the participating rheumatologists based on years of training or possible training or site bias.
What do the results means for you?
Even though the participating rheumatology centers were conducting clinical trials, much of the heart disease risk assessments were lacking in a large proportion of the lupus patients being cared for. People with lupus should be sure to undergo annual risk assessment for heart disease as recommended by EULAR.
The results of this study indicate that current use of steroids (20 mg/day or more) is perhaps the most significant risk factor for heart disease in individuals with lupus.