Delays in protease inhibitor use in clinical practice.

OBJECTIVE

To determine the clinical factors associated with delayed protease inhibitor initiation.

DESIGN

Chart review and telephone survey.

SETTING

General medicine practice at an academic medical center in Boston, Mass.

PATIENTS

One hundred ninety patients living with HIV and a viral load of more than 10,000 copies/ml.

MEASUREMENTS AND MAIN RESULTS

The main outcome measurement was time to first protease inhibitor prescription after first elevated HIV viral load (>10,000 copies/ml). In this cohort, 190 patients had an elevated viral load (median age 39; 87% male; 12% history of injection drug use; 63% AIDS; 53% with depression; 17% history of pneumocystis pneumonia; 54% CD4 <200). In Cox proportional hazards modeling, significant univariate correlates for delayed protease inhibitor initiation were higher CD4 cell count (hazard ratio [HR] 2. 38 for CD4 200-500 compared with <200, 95% confidence interval [CI] 1.59, 3.57; and HR 8.33 for CD4> 500; 95% CI 2.63, 25.0), higher viral load (HR 0.43 for each 10-fold increase; 95% CI 0.31, 0.59), injection drug use (HR 2.08; 95% CI 1.05, 4.17), AIDS (HR 0.24; 95% CI 0.15, 0.36), and history of pneumocystis pneumonia (HR 0.32; 95% CI 0.21, 0.49). In multivariate models adjusted for secular trends in protease inhibitor use, factors significantly associated with delay of protease inhibitor initiation (p <.05) were higher CD4 cell count (for CD4 200-500, HR 2.63; 95% CI 1.61, 4.17; for CD4> 500, HR 11.11; 95% CI 3.57, 33.33), higher viral load (HR 0.66 for each 10-fold increase; 95% CI 0.45, 0.98), history of pneumocystis pneumonia (HR 0.57; 95% CI 0.37, 0.90), history of depression (HR 1. 49; 95% CI 1.03, 2.13), and history of injection drug use (HR 2.70; 95% CI 1.35, 5.56).

CONCLUSIONS

HIV-infected patients with higher CD4 cell counts or a history of depression or history of injection drug use have significant and lengthy delays of protease inhibitor therapy. Although some delays may be clinically appropriate, enhancement of provider and patient education might prove beneficial. Further research should examine reasons for delays in protease inhibitor initiation and their appropriateness.