Background/Purpose:  Patients with rheumatoid arthritis (RA) have increased cardiovascular risk. In the general population, exercise improves several cardiovascular risk factors, including HDL cholesterol concentrations. Although exercise is known to improve quality of life measures in patients with RA, less is known about its effects on cardiovascular risk factors, particularly lipoprotein particle concentrations, which provide information not always concordant to that of lipoprotein cholesterol concentrations. Therefore, we examined the hypothesis that increased exercise is associated with beneficial effects on cardiovascular risk factors, including HDL particle concentration.

Methods: Patient-reported exercise outside of daily activities was quantified as metabolic equivalents measured in minutes per week (METmin/week), according to the 2011 Compendium of Physical Activities, in 165 patients with RA. Hypertension was defined as current use of anti-hypertensive agents or systolic blood pressure ≥140 mmHg and/or a diastolic pressure ≥90 mmHg. Insulin resistance was measured by the homeostasis model assessment of insulin resistance (HOMA). Standard lipid profiles were measured by our diagnostic clinical laboratory, whereas HDL and LDL particle concentrations were determined by nuclear magnetic resonance spectroscopy (LipoScience). The relationship between METmin/week and cardiovascular risk factors was assessed with Spearman correlation and with linear and logistic regression with adjustment for age, race and sex.

Results: The mean ± standard deviation [range] of exercise was 311 ± 786 METmin/week [0 – 7200 METmin/week]. Exercise was inversely associated with heart rate (P=0.02), waist-hip ratio (P=0.02), and systolic blood pressure (0.03), but not with the degree of insulin resistance (HOMA) or BMI. We found no significant association between exercise and LDL or HDL cholesterol concentrations. Exercise was positively associated with the concentration of both total and small HDL particles (P=0.003 and P=0.001, respectively), but not with LDL particle concentrations (Table). Those who exercised had 2.6 μmol/L greater HDL particle concentration (P=0.002) and 2.8 μmol/L greater small HDL particle concentration (P=0.001), after adjustment for age, race and sex.

Conclusion:   The amount of self-reported exercise in patients with RA was independently associated with beneficial changes in several cardiovascular risk factors including heart rate, waist-hip ratio, systolic blood pressure and HDL particle concentration.