Purpose: To determine the effect of prednisone dose and hydroxychloroquine dose on the coronary artery disease risk factors serum cholesterol level, mean arterial blood pressure, and weight in patients with systemic lupus erythematosus.
Patients and methods: A longitudinal cohort study of 264 patients with systemic lupus erythematosus was conducted. For all patients in the cohort, serum cholesterol, mean arterial pressure, weight, prednisone dose, hydroxychloroquine dose, and other potential confounding variables were recorded at each visit. Regression analysis appropriate for longitudinal data was used to assess the effect of prednisone on serum cholesterol and mean arterial pressure. To assess the effect of prednisone on weight, patients' weights were compared 90 days before and after a 10-mg or 20-mg increase in prednisone.
Results: A total of 3,027 patient visits were analyzed. In the regression model for serum cholesterol, a change in prednisone dose of 10 mg was associated with a change in cholesterol of 7.5 +/- 1.46 (SE) mg% after adjustment for the other significant variables in the model, including sex, race, hydroxychloroquine dose, and proteinuria. In the regression model for hydroxychloroquine, the 200-mg and the 400-mg dose were both associated with lower serum cholesterol (8.9 +/- 3.44 SE mg%). In the regression model for mean arterial blood pressure, a 10-mg change in prednisone dose led to a change in mean arterial blood pressure of 1.1 mm Hg after adjustment for age, weight, and antihypertensive drug use. A 10-mg increase in prednisone dose was associated with a mean weight change of 5.50 +/- 1.23 (SE) lb.
Conclusions: Changes in prednisone dose led to definable changes in risk factors for coronary artery disease, even after adjustment for other variables known to affect these risk factors. According to longitudinal regression analysis, hydroxychloroquine therapy was associated with lower serum cholesterol.