Ahmed M. Bayoumi, MD, MSc, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada
Most studies of utilities among Human Immunodeficiency Virus (HIV)-positive individuals predated currently used antiretroviral therapies and accompanying toxicities. We evaluated the association between antiretroviral drugs, symptoms, and utilities. We conducted 206 interviews using a computer to illustrate tradeoffs, conduct surveys, and store data. We elicited utilities using the Rating Scale (RS), Time Trade-Off (TTO), and Standard Gamble (SG) methods and symptoms using a modified HIV-specific scale. We retrieved drug information from respondents' charts. The median number of cumulative antiretrovirals used was 4 (interquartile range [IQR] = 3 to 5). At the time of the interview, 69 participants (34%) were not taking antiretrovirals, 61 (30%) were taking 2 or 3 drugs, 36 (18%) were taking 4 drugs, and 65 (32%) were taking 5 or more drugs. Only 6 participants (3%) reported having no symptoms. The typical respondent had 6 (IQR=4-9) mild and 2 (0-5) severe symptoms. The most common symptom was fatigue, which was mild in 96 (47%) and severe in 68 (33%). The intraclass correlation coefficient between SG and TTO scores was 0.65. There was no association between RS, SG, or TTO utility scores and the number of drugs (p for trend = 0.38, 0.68, and 0.31, respectively). There was only one statistically significant association between any utility score and a drug class: participants using a non-nucleoside reverse transcriptase inhibitor had a higher RS score than patients not using such a drug (0.56 vs. 0.47). Several symptoms were significantly associated with SG and TTO utilities, including fatigue, fevers, cognitive difficulties, diarrhea, depression, anxiety, skin problems, respiratory problems, anorexia, muscle and joint pain, sexual difficulties, and weight loss. Peripheral pain and headache were associated only with the SG; abdominal pain and physical changes related to the lipodystrophy syndrome only with the TTO. Not associated with the SG or the TTO were dizziness, nausea, sleep problems, and hair loss. RS utilities were associated only with skin and respiratory problems. Each severe symptom decreased SG and TTO scores by 0.019 (95% confidence interval 0.010 to 0.028) and 0.024 (0.014 to 0.034), respectively. Utility scores are strongly associated with symptom burden in HIV but not with antiretroviral therapy use. Our study suggests that SG and TTO scores are valid measures of symptom burden but RS scores are not.
See more of Oral Concurrent Session A - Quality of Life and Utility Theory
See more of The 27th Annual Meeting of the Society for Medical Decision Making (October 21-24, 2005)