Background Patients with systemic lupus erythematosus (SLE) have an increased prevalence of insulin resistance and the metabolic syndrome. Exercise has been shown to improve insulin resistance and components of the metabolic syndrome in the general population. However, few studies have evaluated the effects of exercise on the metabolic health of patients with SLE.
Objectives Determine the relationship between exercise and metabolic health in SLE patients.
Methods We performed a cross sectional study of 165 patients with SLE and recorded the amount of dedicated exercise performed outside of daily activities as metabolic equivalents in minutes per week (METs). We measured clinical variables, fasting insulin and glucose, and calculated the homeostasis model assessment (HOMA) as a measure of insulin resistance. Metabolic syndrome was defined by the National Cholesterol Education Program Adult Treatment Panel III definition. Current MET expenditure was categorized into quartiles and we used these to determine the relationship between exercise and the metabolic syndrome and its individual components using binary logistic regression and multivariable regression analyses adjusting for age, race and sex.
Results Patients with SLE (n=165) had a median [IQR] age of 41 years [30-48], 89.1% were female, median BMI was 27.5 kg/m2 [23.6-32.74], and 29% had metabolic syndrome. Median disease duration was 7 years [3-12] and SLEDAI was 4 [0-6]. The median exercise expenditure was 200 MET min/week [0-591.75]. With each quartile increase in METs, resting heart rate decreased by 2.3 beats per minute (95% CI, 0.7-4.0 beats per minute) (P=0.006). The odds of having metabolic syndrome was decreased by 25.9% (0.8-44.6%) for each quartile increase in METs (P=0.044). Each increasing quartile of exercise was associated with a 12.3% (0.2-22.9%) decrease in HOMA (P=0.045), 8.9 mg/dl (0.5-17.3 mg/dl) decrease in triglycerides (P=0.037), and 2.5 mg/dl (0.7-4.3 mg/dl) increase in HDL (P=0.006), but no significant change in the presence of hypertension (P=0.10), fasting glucose level (P=0.14), or BMI (P=0.11). There was a non-significant trend toward decreased waist circumference with increasing exercise (P=0.06).
Conclusions Some metabolic benefits are associated with the amount of exercise performed in patients with SLE, particularly decreased odds of having metabolic syndrome and improvement in insulin resistance, triglyceride, and HDL levels. Future interventional studies to determine if exercise can prevent or reverse the metabolic syndrome and its associated adverse cardiometabolic risk factors in patients with SLE patients will be of interest.
Disclosure of Interest None Declared