As many as one-third of patients with coronary heart disease who have met target low-density lipoprotein cholesterol levels undergo repeat lipid testing within months, without any further intensification of treatment, according to a large analysis published online July 1 in JAMA Internal Medicine.
Such patients are already being treated aggressively, and repeat lipid testing in them likely represents an overuse or waste of health care resources, said Dr. Salim S. Virani of the Health Policy and Quality Program, Michael E. DeBakey VA Medical Center Health Services Research and Development Center of Excellence, Houston, and his associates.
In a study involving nearly 28,000 CHD patients who made a primary care visit to a Veterans Affairs medical center or community-based outpatient clinic during a 1-year period, 12,686 such "redundant" lipid panels were performed at an average cost of about $16 each. "This is equivalent to $203,990 in annual costs for one VA network, and does not take into account the cost of the patient’s time to undergo lipid testing and the cost of the provider’s time to manage these results and notify the patient," the investigators said.
"Our results highlight areas to target for future quality improvement initiatives," they noted.
In the study, Dr. Virani and his colleagues identified 27,947 patients with CHD who were taking a variety of lipid-lowering medications and who had attained the guideline-recommended low-density lipoprotein (LDL) cholesterol target of less than 100 mg/dL. The mean age of these study subjects was 73 years, and most were white men. The prevalence of hypertension was 86%, and that of diabetes was 44%.
The study subjects had well-controlled lipid levels, with excellent mean baseline levels of LDL cholesterol (70 mg/dL), non-HDL cholesterol (94 mg/dL), triglycerides (123 mg/dL), and HDL cholesterol (43 mg/dL). Most (72%) were taking statins.
A total of 9,200 underwent repeat lipid panels within 11 months, without any intensification of their treatment. This ruled out any patients who might have been attempting to reach an even lower LDL cholesterol target of less than 70 mg/dL.
In these 9,200 patients, "it is likely that repeat lipid testing was performed without any clinical action," and therefore was redundant, the researchers said (JAMA Intern. Med. 2013 July 1 [doi: 10.1001/jamainternmed. 2013.8198]).
A total of 34% of the repeat lipid tests were done within 6 months of an index test, and 80% were done within 9 months. Their results were "strikingly similar" to those of the index lipid panels, which also "argues against major medication or therapeutic lifestyle changes as the drivers of repeat lipid testing."
A sensitivity analysis involving a subset of 13,114 patients who had optimal (below 70 mg/dL) LDL levels showed that 62% underwent repeat lipid testing, confirming that redundancy was commonplace even in these patients.
Patients who had concomitant hypertension or diabetes were the most likely to undergo repeat lipid panels, which "points toward a tendency of health care providers to order frequent laboratory testing in complex patients. Frequent lipid testing in these patients likely represents providers’ practice to order comprehensive laboratory tests (including lipid levels) rather than focusing on one clinical issue (e.g., ordering only glycated hemoglobin measurement to assess diabetes control)," Dr. Virani and his associates said.
"Repeat lipid testing likely provides a sense of comfort to the providers that they are being vigilant in following up on their patients with CHD, although a repeat lipid panel may not be indicated," they added.
Their study was limited in that it included few women, and minority races/ethnicities were underrepresented. The findings therefore may not be generalizable to these groups, the investigators said.
Dr. Virani reported no financial conflicts of interest; one of his associates reported ties to numerous industry sources.