Laboratory monitoring of drugs at initiation of therapy in ambulatory care
Received: 27 May 2005 Revised: 08 August 2005 Accepted: 08 August 2005 DOI:
Cite this article as: Raebel, M.A., Lyons, E.E., Andrade, S.E. et al. J GEN INTERN MED (2005) 20: 1120. doi:10.1111/j.1525-1497.2005.0257.x Abstract Product labeling and published guidelines reflect the importance of monitoring laboratory parameters for drugs with a risk of organ system toxicity or electrolyte imbalance. Limited information exists about adherence to laboratory monitoring recommendations. The objective of this study was to describe laboratory monitoring among ambulatory patients dispensed medications for which laboratory testing is recommended at therapy initiation. BACKGROUND AND OBJECTIVES: We conducted a retrospective cross-sectional analysis of patients in 10 geographically distributed health maintenance organizations who were newly prescribed medications with recommended laboratory test monitoring. The main outcome measure was the proportion of initial drug dispensing without recommended baseline laboratory monitoring for 35 newly initiated drugs or drug classes. DESIGN AND SUBJECTS: One hundred seven thousand, seven hundred sixty-three of 279,354 (39%) initial drug dispensings occurred without recommended laboratory monitoring. Patients without monitoring were younger than patients who had monitoring (median 57 vs 61 years, RESULTS: P<.001). Thirty-two percent of dispensings where a serum creatinine was indicated did not have it evaluated (range across drugs, 12% to 61%); 39% did not have liver function testing (range 10% to 75%); 32% did not have hematologic monitoring (range 9% to 51%); and 34% did not have electrolyte monitoring (range 20% to 62%) ( P<.001). Substantial opportunity exists to improve laboratory monitoring of drugs for which such monitoring is recommended. This study emphasizes the need for research to identify the clinical implications of not conducting recommended laboratory monitoring, existing barriers to monitoring, and methods to improve practice. CONCLUSIONS: Key Words laboratory monitoring ambulatory drug therapy
The authors have no conflicts of interest to declare for this article.
Authors had access to study data, take responsibility for the accuracy of the analysis, and had authority over manuscript preparation and the decision to submit the manuscript for publication.
Previous Presentation: Portions of this work were presented during the HMO Research Network 10th Annual Meeting on May 5, 2004, in Dearborn, Mich.
Funding/Support and Role of Sponsor: This work was supported by a cooperative agreement (U18 HS 11832) from the Agency for Healthcare Research and Quality (AHRQ). AHRQ did not design or conduct the study, collect, management, analyze, or interpret the data, nor did it have a role in the preparation, review, or approval of the manuscript.
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