Patients with rheumatoid arthritis who stop taking their statins are at greatly increased risk of death, a longitudinal study found.

After adjustment for variables including age, sex, and comorbidities, patients who discontinued statin therapy had a 60% increase in cardiovascular mortality (HR 1.60, 95% CI 1.15 to 2.23, P=0.005), according to Mary A. De Vera, PhD, of the Arthritis Research Centre of Canada in Vancouver, and colleagues.

Discontinuation also was associated with a 79% increase in all-cause mortality (HR 1.79, 95% CI 1.46 to 2.20, P<0.0001), the researchers reported online in Arthritis Care & Research.

Patients with rheumatoid arthritis have twice the risk of cardiovascular mortality compared with the general population, and statins are recommended in these patients for cholesterol lowering and to prevent ischemic heart disease.

Previous studies have suggested that more than half of all individuals who are prescribed statins eventually stop taking them, and De Vera’s group reported earlier that more than one-third of patients with rheumatoid arthritis discontinued the drugs over an 8-year period.

To explore the impact of this on mortality, the researchers analyzed data from an established cohort of 37,000 patients with rheumatoid arthritis in British Columbia, and determined that 4,102 had been prescribed a statin.

- Mean age of the patients was 66.6 years, and mean disease duration was 19 months. A total of 60% were women.

During 16,144 person-years of follow-up, 45.4% of patients discontinued taking a statin.

And during a mean follow-up of 4 years, there were 467 deaths from any cause and 198 deaths from cardiovascular disease. Among patients who died of cardiovascular disease, the most common causes were acute myocardial infarction in 31.3%, ischemic heart disease in 30.8%, and cerebrovascular accidents in 15.2%.

Aside from statin discontinuation, other factors associated with heightened risk of cardiovascular death were:

The researchers also calculated the effects of time since discontinuation and found a 0.4% increase in cardiovascular mortality for each month since stopping treatment (HR 1.004, 95% CI 1.001 to 1.016). For all-cause mortality, factors other than stopping statin treatment that were associated with risk included: Current arthritis treatments also influenced all-cause mortality, according to the researchers.