Predictors and impact of self-reported suboptimal effort on estimates of prevalence of HIV-associated neurocognitive disorders

Andrew J. Levine, Eileen Martin, Ned Sacktor, Cynthia Munro, James Becker

Research output: Contribution to journalArticle


BACKGROUND:: Prevalence estimates of HIV-associated neurocognitive disorders (HAND) may be inflated. Estimates are determined via cohort studies in which participants may apply suboptimal effort on neurocognitive testing, thereby inflating estimates. Additionally, fluctuating HAND severity over time may be related to inconsistent effort. To address these hypotheses, we characterized effort in the Multicenter AIDS Cohort Study. METHODS:: After neurocognitive testing, 935 participants (525 HIV-, 410 HIV+) completed the Visual Analogue Effort Scale (VAES), rating their effort from 0-100%. Those with <100% then indicated the reason(s) for suboptimal effort. K-means cluster analysis established 3 groups: high (mean=97%), moderate (79%), and low effort (51%). Rates of HAND and other characteristics were compared between groups. Linear regression examined predictors of VAES score. Data from 57 participants who completed the VAES at two visits was analyzed to characterize the longitudinal relationship between effort and HAND severity. RESULTS:: Fifty-two percent of participants reported suboptimal effort (<100%) effort, with no difference between serostatus groups. Common reasons included “tired” (43%) and “distracted” (36%). The lowest effort group had greater ANI and MND diagnosis (25 and 33%) as compared to the moderate (23% and 15%) and the high effort groups (12% and 9%). Predictors of suboptimal effort were self-reported memory impairment, African-American race, and cocaine use. Change in effort between baseline and follow-up correlated with change in HAND severity. CONCLUSION:: Suboptimal effort appears to inflate estimated HAND prevalence and explain fluctuation of severity over time. A simple modification of study protocols to optimize effort is indicated by the results.

Original languageEnglish (US)
JournalJournal of Acquired Immune Deficiency Syndromes
StateAccepted/In press - Mar 22 2017


ASJC Scopus subject areas

  • Pharmacology (medical)
  • Infectious Diseases

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