Management of Cardiovascular Disease Risk in Rheumatoid Arthritis

Meta-analyses of randomized controlled trials have estimated that lipid-lowering therapy with HMG-CoA reductase inhibitors (statins) reduces the risk of CVD by 25% to 30%; as such, statin therapy has become the standard of care for reduction of CVD risk in the general population.¹² Benefits for primary prevention of CVD in RA have also been observed; statin therapy was associated with a reduced risk of CVD events (hazard ratio [HR], 0.45; 95% confidence interval [CI], 0.20-0.98) and all-cause mortality (HR, 0.43; 95% CI, 0.20-0.92) in a population-based cohort study.¹³ Statins appear to have similar lipid-lowering effects and result in similar CVD risk reduction when used for primary or secondary prevention in RA patients compared to non-RA controls.^14-16 Additionally, anti-inflammatory properties of statins may act in synergy with disease-modifying antirheumatic drugs (DMARDs) to improve RA disease activity. In a small study of RA patients, statin therapy improved subjective and objective markers of RA disease activity in conjunction with methotrexate.¹⁷

While statins provide robust reduction in CVD risk, some individuals cannot tolerate statin therapy or do not achieve goal LDL levels with statin therapy. Select non-statin LDL-cholesterol-lowering agents have shown promise for reducing CVD events in the general population.¹⁸ Ezetimibe, which inhibits cholesterol absorption in the small intestine, very modestly reduced CVD events when added to atorvastatin (relative risk [RR], 0.94; 95% CI, 0.89-0.99) in a double-blind randomized controlled trial.¹⁹ Novel monoclonal antibodies to proprotein convertase subtilisin/kexin type 9 (PCSK-9) inhibit the internalization of surface LDL receptors, promoting LDL clearance. Two PCSK-9 inhibitors, alirocumab and evolocumab, were approved by the US Food and Drug Administration (FDA) after randomized controlled trials demonstrated their efficacy in lowering LDL by approximately 60% and reducing CVD events by approximately 15% in patients on maximum-tolerated statin therapy.^20-22 To date, non-statin LDL-cholesterol-lowering agents have been subject to limited study in RA.²³

Identification and management of dyslipidemia offers an opportunity for substantial CVD risk reduction at the RA population level. Unfortunately, current rates of lipid screening are inadequate in this high-risk group. In a study of 3298 Medicare patients with RA, less than half of RA patients with an indication underwent appropriate lipid screening.²⁴ Additionally, statins are often underutilized for both primary and secondary prevention in RA patients. Only 27% of RA patients meeting National Cholesterol Education Program Adult Treatment Panel III criteria were initiated on statin therapy in a population-based cohort study.²⁵ Among patients discharged after a first myocardial infarction (MI), the odds of receiving lipid-lowering therapy were 31% lower for RA patients (odds ratio [OR], 0.69; 95% CI, 0.58-0.82).²⁶ Similar to the general population, adherence to statins in RA patients appears to be poor.^27-30 This raises particular concern considering that a population-based cohort study of RA patients demonstrated a 67% increased risk of MI associated with statin discontinuation, regardless of prior MI status.²⁷ Providers—rheumatologists, primary care providers, and cardiologists alike—need to remain vigilant in efforts to assess CVD risk to identify patients who will benefit from lipid-lowering therapy and to emphasize the importance to patients of statin adherence. Novel models of health-care delivery, health technologies, and patient engagement in care may prove useful for improving lipid screening and management in RA.

Tobacco Use

Cigarette smoking is a shared risk factor for both CVD and RA. Large cohort studies have identified a dose-dependent increased risk of incident RA, particularly seropositive RA, among smokers.^31-34 Tobacco smoking has also been associated with increased levels of inflammation and RA disease activity.³⁵ The consequences of tobacco use in the general population are staggering. Among individuals over the age of 30 years, tobacco use is responsible for 12% of all deaths and 10% of all CVD deaths.³⁶ Similar findings are observed in RA; a recent meta-analysis estimated there is a 50% increased risk of CVD events in RA related to smoking tobacco.³⁷ In the general population, smoking cessation markedly lowers CVD risk, and over time CVD risk may approach that of nonsmokers.^38,39 Thus, regular counseling and interventions to facilitate smoking cessation are critical to reducing CVD risk in RA patients. RA-specific smoking cessation programs have been proposed, but have yet to outperform standard smoking cessation programs.⁴⁰

Diabetes Mellitus

It is estimated that almost 10% of the US population has diabetes mellitus (DM), which in isolation portends substantial CVD risk.⁴¹ There is an increased prevalence of DM in RA, perhaps owing to factors such as physical inactivity and chronic glucocorticoid use, though a higher level of RA disease activity itself has been associated with increased insulin resistance.^42-45 In a cohort of 100 RA patients who were neither obese nor diabetic, RA patients had significantly higher fasting blood glucose and insulin levels than age- and sex-matched controls. These findings were even more pronounced in RA patients with higher levels of disease activity.⁴⁴ Similar to the general population, DM is associated with poor CVD outcomes in RA.³⁷ Therefore, both appropriate management of diabetes and control of RA disease activity are vitally important to minimize CVD risk related to DM.