Correlates of repeat lipid testing in patients with coronary heart disease

Abstract

Importance: Understanding the frequency and correlates of redundant lipid testing could identify areas for quality improvement initiatives aimed at improving the efficiency of cholesterol care in patients with coronary heart disease (CHD).

Objective: To determine the frequency and correlates of repeat lipid testing in patients with CHD who attained low-density lipoprotein cholesterol (LDL-C) goals and received no treatment intensification.

Design, setting, and participants: We assessed the proportion of patients with LDL-C levels of less than 100 mg/dL and no intensification of lipid-lowering therapy who underwent repeat lipid testing during an 11-month follow-up period. We performed logistic regression analyses to evaluate facility, provider, and patient characteristics associated with repeat testing. In total, we analyzed 35,191 patients with CHD in a Veterans Affairs network of 7 medical centers with associated community-based outpatient clinics.

Main outcomes and measures: Frequency and correlates of repeat lipid testing in patients having CHD with LDL-C levels of less than 100 mg/dL and no further treatment intensification with lipid-lowering therapies.

Results: Of 27,947 patients with LDL-C levels of less than 100 mg/dL, 9200 (32.9%) had additional lipid assessments without treatment intensification during the following 11 months (12 ,686 total additional panels; mean, 1.38 additional panel per patient). Adjusting for facility-level clustering, patients with a history of diabetes mellitus (odds ratio [OR], 1.16; 95% CI, 1.10-1.22), a history of hypertension (OR, 1.21; 95% CI, 1.13-1.30), higher illness burden (OR, 1.39; 95% CI, 1.23-1.57), and more frequent primary care visits (OR, 1.32; 95% CI, 1.25-1.39) were more likely to undergo repeat testing, whereas patients receiving care at a teaching facility (OR, 0.74; 95% CI, 0.69-0.80) or from a physician provider (OR, 0.93; 95% CI, 0.88-0.98) and those with a medication possession ratio of 0.8 or higher (OR, 0.75; 95% CI, 0.71-0.80) were less likely to undergo repeat testing. Among 13,114 patients who met the optional LDL-C target level of less than 70 mg/dL, repeat lipid testing was performed in 8177 (62.4% of those with LDL-C levels of <70 mg/dL) during 11 follow-up months.

Conclusions and relevance: One-third of patients having CHD with LDL-C levels at goal underwent repeat lipid panels. Our results highlight areas for quality improvement initiatives to reduce redundant lipid testing. These efforts would be more important if the forthcoming cholesterol guidelines adopt a medication dose-based approach in place of the current treat-to-target approach.