Clinical Impact and Cost of Laboratory Monitoring Need Review Even in Resource-Rich Setting

Abstract

To the Editors: Multiple studies have demonstrated the relatively low clinical impact and cost of frequent laboratory monitoring of asymptomatic patients receiving antiretroviral therapy (ART) in resource-poor settings.1,2 We propose taking these conclusions a step further into resource-rich settings given the rising cost of healthcare. The costs for treatment and medical care of an HIV-positive individual in the United States are as high as $34,000 per year with estimated lifetime costs surpassing 1 million dollars per patient.3 Furthermore, it is anticipated that the number of patients on ART, the time on therapy, and the commensurate costs will continue to increase.4-10 Given this rising number, it is critical that evidence based on best practices with regard to efficacy, safety, and cost-effectiveness is employed in the treatment of HIV. Current HIV treatment guidelines recommend that routine laboratory monitoring should be conducted every 3 months to monitor treatment effects, virologic breakthroughs, and timely detection of toxicities.8 However, with the advent of newer more efficacious ARTs with reduced toxicities, these older recommendations need to be re-evaluated. We conducted a retrospective cohort study of existing medical record data in our Southern California clinics to evaluate differences in HIV-1 RNA levels and CD4+ cell counts of patients seen every 3 months as compared with those seen every 6 months. We selected records for inclusion in this analysis if the patient had (1) been on antiretroviral therapy for at least 3 months before data extraction, (2) >95% adherence to ARTs, and (3) had routine CD4+ cell counts and HIV-1 RNA levels checked either at 3-month or at 6-month intervals. We selected patients with high adherence to limit potential confounding effects of adherence on the biomarkers of interest. Between September 1, 2008, and September 1, 2009, a total of 846 eligible patients were identified and included in our analysis. We found no differences in terms of gender, race/ethnicity, baseline CD4+ cell counts, and HIV-RNA levels between those who were seen at regularly scheduled 3-month follow-up visits as compared with those who had a 6-month follow-up visit (Table 1). No differences were noted in HIV-1 RNA levels at follow-up (P value = 0.65), however, clinically minimal though statistically significant improvements were noted in CD4+ cell counts (29 cells/uL vs. 6 cells/uL; P = 0.03).TABLE 1: Demographic and Clinical Characteristics of Patients Seen Quarterly as Compared With Patients Seen Semiannually, AIDS Healthcare Foundation, Los Angeles, CA, September 1, 2008, to September 1, 2009One of the critical questions regarding antiretroviral therapy management is what constitutes optimal monitoring, and clearly this issue has implications for resources allocation. Evidence should guide policies for laboratory monitoring, especially if data shows that this may not be a good use of resources. Nationally, there is a need for a randomized prospective study evaluating the safety of limited laboratory monitoring in stable patients on ART to demonstrate if this is a good use of resources in a time of dwindling health care dollars. Shilpa Sayana, MD, MPH* Marjan Javanbakht, PhD† Michael Weinstein* Homayoon Khanlou, MD* *AIDS Healthcare Foundation Los Angeles, CA †University of Los Angeles, California