The risk of myocardial infarction is just as high in patients who have chronic kidney disease as in those who have diabetes, and their subsequent mortality is even higher, according to a report published online June 19 in the Lancet.
"Our research suggests that there is a strong case for considering CKD to be a coronary heart disease risk equivalent," as is the case with diabetes. This means that people with CKD, like diabetes patients, "are at a comparable risk of coronary events to those who have previously had a heart attack," Dr. Marcello Tonelli of the departments of medicine and public health sciences at the University of Alberta, Edmonton, said in a press statement accompanying the release of the report.
Dr. Tonelli and his associates used information from two large, population-based cohorts – the Alberta Kidney Disease Network and the National Health and Nutrition Examination Survey (NHANES) 2003-2006 – to compare the risks of hospitalization for MI among adults with previous MI, adults with diabetes mellitus but no kidney disease, and adults with CKD but no diabetes. The 1,268,029 study subjects were followed for a median of 4 years, during which time 1% (11,340) were admitted for MI.
Compared with healthy adults, the unadjusted rate of MI during follow-up was highest in people with a history of MI (18.5 per 1,000 person-years) but was also significantly elevated in those with diabetes (5.4 per 1,000 person-years) or CKD (6.9 per 1,000 person-years).
In addition, the proportion of patients who died within 30 days of admission for MI was highest for patients with CKD (14%) but also was significantly elevated for patients with diabetes (8%) and those with a history of MI (10%).
These findings suggest that "arguments supporting inclusion of diabetes in the highest risk category for CHD seem also to apply to people with CKD," the investigators said (Lancet 2012 June 19 [doi:10.1016/S0140-6736(12)60572-8]).
In exploratory analyses in which the data were adjusted to account for patient age, socioeconomic status, and comorbidities, the MI rate decreased in those with CKD but not in those with diabetes. This suggests that demographic and clinical characteristics – most notably, old age – are responsible for much of the cardiovascular risk associated with CKD, they noted.
The study findings also imply that patients with CKD, like those with diabetes, would benefit from lipid-lowering treatment.
This study was supported by the Alberta Heritage Foundation for Medical Research, Alberta Health and Wellness, the University of Alberta, and the University of Calgary. Dr. Tonelli reported ties to Pfizer and Merck, and one of his associates reported ties to Amgen.