Do Glucocorticoids Increase Mortality in Patients With RA and Diabetes?

Glucocorticoid therapy may be associated with a higher mortality rate among patients with rheumatoid arthritis (RA) and comorbid type 2 diabetes mellitus (T2DM) compared with patients with RA who do not have T2DM, according to a new retrospective cohort study.

To reach this conclusion, the researchers identified 9085 patients with incident RA from the United Kingdom’s primary care electronic medical records with linkage to the Office for National Statistics for mortality data. The study period was from January 1, 1998, to October 1, 2011.

T2DM was identified through Read codes—the United Kingdom’s former clinical terminology system—as well as through prescriptions and blood tests. Glucocorticoid use was identified through prescriptions.

The researchers determined that, among patients without T2DM, glucocorticoid use had a 4.4-fold increase in the all-cause mortality rate ratio (95% CI, 3.83-5.14) compared with no use of glucocorticoid.

Meanwhile, patients with T2DM had a lower mortality rate ratio of 3.02 (95% CI, 2.34-3.90) for glucocorticoid use.

Still, because of their higher baseline risk, patients with T2DM had a higher mortality rate difference associated with glucocorticoid use.

In patients with T2DM, treatment with glucocorticoids was associated with an additional 46.7 deaths per 1000 person-years (95% CI, 34.1-59.3) compared with patients with T2DM who were not treated with glucocorticoids. Patients who were treated with glucocorticoids but who did not have T2DM experienced an additional 36.2 deaths per 1000 person-years (95% CI, 31.6-40.8). 

A similar pattern was seen for cardiovascular (CV) mortality.

While the adjusted Cox proportional hazards model showed no evidence of multiplicative interaction, additive interaction indicated a nonsignificant increased risk. Furthermore, there was no interaction on either scale for CV mortality.

“[Glucocorticoid] use was associated with higher mortality rates in people with comorbid DM compared to people without DM, despite apparently reassuring similar relative risks,” the researchers concluded. “Clinicians need to be aware of the higher baseline risk in patients with DM and consider this when prescribing [glucocorticoids] in patients with RA and comorbid DM.”

—Colleen Murphy

Reference:

Costello RE, Marsden A, Movahedi M, et al. The effect of glucocorticoid therapy on mortality in patients with rheumatoid arthritis and concomitant type II diabetes: a retrospective cohort study. BMC Rheumatology. 2020;4(4). doi:10.1186/s41927-019-0105-4