SLE Medicaid patients have higher 30-day death rate compared to those with diabetes
New research found that the 30-day death rate for Medicaid patients with systemic lupus erythematosus (SLE) who underwent coronary revascularization procedures for cardiovascular disease was double that of patients with diabetes mellitus who underwent the same procedures. This study will be presented at the 2019 ACR/ARP Annual Meeting (Abstract # 897).
Systemic lupus erythematosus, referred to as SLE or lupus, is a chronic (long-term) disease that causes systemic inflammation which affects multiple organs and can be deadly. In addition to affecting the skin and joints, it can affect other organs in the body such as the kidneys, brain, the tissue lining the lungs (pleura) and/or heart (pericardium). Many patients experience fatigue, weight loss, and fever.
This research group previously found that although there were similar myocardial infarction risks in patients with SLE or diabetes mellitus (DM), for unknown reasons the rates of coronary revascularization procedures among SLE patients enrolled in Medicaid were 18 percent higher than age- and sex-matched diabetes patients. Although DM patients are known to have an elevated absolute risk of death after coronary revascularization procedures, little is known about mortality after these heart procedures in lupus patients. The researchers conducted a study to determine the outcomes in SLE patients compared to patients with DM as well as patients in the general population. Patients in each cohort were enrolled in Medicaid.
The researchers used Medicaid Analytic eXtract data containing billing claims from the 29 most populated states in the United States from 2007 to 2010. They identified adults 18 to 65 years old with prevalent SLE or DM based on the ninth edition of the International Classification of Diseases (ICD-9) codes. They also included patients without SLE or DM for the general population cohort.
Researchers identified coronary revascularization procedures among 608 SLE patients, 1,185 DM patients and 628 general population patients. Each group had a similar follow-up period of approximately two years (1.7). SLE patients had the highest 30-day post-revascularization mortality rate (351.35) per 1,000 person years of observation compared to 210.4 in the DM group and 189.9 in the general population. The analysis showed that lupus patients had double the odds of death within 30 days after a coronary revascularization compared to patients with DM. They also found a similar, but non-significant trend for SLE patients compared to the general population, although this was limited by very few deaths in the general population group.
"The results suggest that Medicaid SLE patients undergoing coronary revascularization procedures had an increased risk of death compared to similar diabetes mellitus patients having the same procedures. This may be due to severity of cardiovascular disease and overall health status in SLE patients selected for these procedures," said Medha Barbhaiya, MD, a rheumatologist and clinical researcher the Hospital for Special Surgery and the study's lead author. "Future studies accounting for the complexity and indications of the procedures performed, SLE and cardiac disease severity, and investigating causes of post-procedure deaths are required. Given the small number of deaths observed, this study needs to be replicated in a larger cohort."
Although based on a small number of post-procedural deaths, this study found that the SLE patients had 1.7 times higher 30-day mortality rates post-coronary revascularization compared to DM and general population patients, despite being comparatively much younger on average.