Adherence to protease inhibitors, HIV-1 viral load, and development of drug resistance in an indigent population

• Published in: AIDS (London) Vol. 14; no. 4; pp. 357 - 366
• Main Authors: Bangsberg, David R., Hecht, Frederick M., Charlebois, Edwin D., Zolopa, Andrew R., Holodniy, Mark, Sheiner, Lewis, Bamberger, Joshua D., Chesney, Margaret A., Moss, Andrew
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 10.03.2000
• Subjects: Adult; Anti-HIV Agents - administration & dosage; Anti-HIV Agents - therapeutic use; Biological and medical sciences; Cohort Studies; Drug Resistance, Microbial - genetics; Drug Therapy, Combination; Female; Genotype; HIV Protease Inhibitors - administration & dosage; HIV Protease Inhibitors - therapeutic use; HIV-1 - genetics; HIV-1 - isolation & purification; Homeless Persons; Human immunodeficiency virus 1; Human viral diseases; Humans; Infectious diseases; Male; Medical Indigency; Medical sciences; Multivariate Analysis; Patient Compliance; Reverse Transcriptase Inhibitors - administration & dosage; Reverse Transcriptase Inhibitors - therapeutic use; Viral diseases; Viral diseases of the lymphoid tissue and the blood. Aids; Viral Load; Human; Immunopathology; Accessibility; HIV-1 virus; Retroviridae; Genotype; AIDS; Immune deficiency; Lentivirus; Care; Infection; Virus; Resistance; Chemotherapy; Homeless; Treatment; Viral disease; Antiviral; Treatment compliance; Human immunodeficiency virus; Viral load; Protease inhibitor
• ISSN: 0269-9370
• DOI: 10.1097/00002030-200003100-00008

To examine the relationship between adherence, viral suppression and antiretroviral resistance in HIV-infected homeless and marginally housed people on protease inhibitor (PI) therapy. A cross-sectional analysis of subjects in an observational prospective cohort systematically sampled from free meal lines, homeless shelters and low-income, single-room occupancy (SRO) hotels. Thirty-four HIV-infected people with a median of 12 months of PI therapy. Adherence measured by periodic unannounced pill counts, electronic medication monitoring, and self-report; HIV RNA viral load; and HIV-1 genotypic changes associated with drug resistance. Median adherence was 89, 73, and 67% by self-report, pill count, and electronic medication monitor, respectively. Thirty-eight per cent of the population had over 90% adherence by pill count. Depending on the measure, adherence explained 36-65% of the variation in concurrent HIV RNA levels. The three adherence measures were closely related. Of 20 genotyped patients who received a new reverse transcriptase inhibitor (RTI) when starting a PI, three had primary protease gene substitutions. Of 12 genotyped patients who received a PI without a new RTI, six had primary protease gene substitutions (P < 0.03). A substantial proportion of homeless and marginally housed individuals had good adherence to PI therapy. A strong relationship was found between independent methods of measuring adherence and concurrent viral suppression. PI resistance was more closely related to the failure to change RTI when starting a PI than to the level of adherence.