Positive effect of hydroxychloroquine on lipid profiles of patients with rheumatoid arthritis: A Veterans Affair cohort.

OBJECTIVE

Despite remarkable improvements in rheumatoid arthritis (RA) treatment, there is evidence indicating that the mortality gap between patients with RA and the general population is not closing. The increase in mortality rates in patients with RA is predominantly due to cardiovascular disease (CVD). Literature suggests that important links exist between RA inflammation and atherosclerosis in CVD. Dyslipidemia is a well-known risk factor of atherosclerosis. Previous studies have suggested that antimalarials, chloroquine diphosphate, and hydroxychloroquine (HCQ), used in the treatment of autoimmune diseases, have a beneficial effect on the lipid levels. However, the studies had small sample sizes. We analyzed a Veterans Affair RA cohort of 2,925 patients to characterize the effect of 4 months' use of HCQ on the lipid levels.

METHODS

Data for this cohort were obtained from the department of Veterans Affairs administrative database. Individuals (age ≥18 years) with a diagnosis of RA (ICD-9 code) at 2 or more outpatient visits from 1999 to 2009 were identified. Only the patients with at least 1 lipid level measured at 120-180 days before staring HCQ were included. Lipids levels on pre- and poststart dates of HCQ (120-180 days) were compared using student's t-test and adjusted for age, sex, race, C-reactive protein (CRP), and statin use with multivariable regression (analysis of variance/analysis of covariance) for the change in different lipid levels. To give equal weightage to covariables, we conducted an analysis of marginal means for race in each lipid level. All analyses were performed using STATA 11.

RESULTS

After adjusting for sex, age, race, statin use, and post CRP values >10 mg/dL using a linear regression, the factor driving the change in the different lipid levels was race (p values for total cholesterol, 0.006; low-density lipoprotein, 0.09; non-high-density lipoprotein [HDL], 0.03; atherogenic index, 0.08; and HDL, 0.17). When considering race individually using marginal means analysis, the race in the subgroup "others" was more influential.

CONCLUSION

Our results suggest that sex and race influences the HCQ effect on the lipid profiles in patients with RA. Use of HCQ in males is found to be associated with positive changes in the lipid profiles independent from the use of statins. There is a suggestion that whites and African Americans might be less susceptible to HCQ effect on lipid profiles than other races.