Randomized controlled trial of an intervention to prevent adherence failure among HIV-infected patients initiating antiretroviral therapy.

OBJECTIVE: Compare the efficacy of a multicomponent social support intervention to standard-of-care counseling on medication adherence among HIV-infected patients initiating antiretroviral therapy. DESIGN: Randomized controlled trial. Generalized estimating equations tested for differences in the percentage of participants achieving 90% adherence. MAIN OUTCOME MEASURES: Pill-taking, electronically monitored over 6 consecutive months; plasma viral load (VL), assessed at 3 and 6 months following initiation of therapy. RESULTS: Of 226 participants who were randomized and began the trial, 87 (38%) were lost to the study by 6 months. The proportion of adherent participants declined steadily over time, with no time by group interaction. Sustained adherence was associated with increased odds of achieving an undetectable VL (OR=1.78; 95% CI=1.01, 3.13). In intention-to-treat analyses, a larger proportion of the intervention group than the control group was adherent (40.15% vs. 27.59%, p=.02) and achieved an undetectable VL p=.04). However, the majority of participants who remained on study experienced some reduction in VL (>or=1-log drop or undetectable), regardless of experimental condition. CONCLUSION: The multicomponent social support intervention significantly improved medication adherence over standard-of-care counseling; evidence for improved virologic outcomes was inconsistent. Early discontinuation of care and treatment may be a greater threat to the health of HIV patients than imperfect medication-taking.     

Neurocognitive influences on health behavior in a community sample.

CONTEXT: Dominant models of individual health behavior omit biological variables entirely and are composed almost exclusively of social-cognitive and conative variables. Research from the neurosciences suggests a role for brain function in explaining behaviors that require active self-regulation for consistent performance. However, the association between brain function and health behavior is underexplored. OBJECTIVE: To examine the predictive power of executive function for 2 health risk behaviors and 2 health protective behaviors in healthy adults. DESIGN: A cross-sectional community sample (N = 216) of adults 20-100 years of age were administered a battery of neuropsychological tests and completed self-report questionnaires regarding their health practices. It was hypothesized that poor performance on neuropsychological tests tapping executive function would be associated with poor health behavior tendencies. RESULTS: Errors on the Stroop task were positively associated with health risk behavior and negatively associated with health protective behavior after controlling for demographics, education, and IQ. CONCLUSION: Executive function is associated with health behavior tendencies. If the association is causal, explanatory models of individual health behavior should be revised to account for individual differences in biologically imbued self-regulatory abilities.     

Risky prospects and risk aversion tendencies: does competition in the classroom depend on grading practices and knowledge of peer-status?

When students are faced with the decision of whether to assist a peer, they should be sensitive to the potential risks associated with doing so. Two factors associated with risky helping behaviour in the classroom are: (1) the grading practices that are used, and (2) knowledge of a peer’s relative status. Normative (“curved”) grading creates a situation in which peer-interactions are potentially competitive, but it is only those interactions with peers of a similar status that carry the potential for assistance to be costly to oneself. In two studies, we created hypothetical scenarios in which the grading practices (normative or absolute) and peer-status proximity (proximate, distant, or unknown) were manipulated, and asked participants to report their willingness to cooperate with a peer by sharing their notes from an important lecture. We found that when normative grading was used, individuals were less willing to assist a peer when they knew that the peer’s status was proximate to their own. There was also less cooperation when peer status was unknown, under normative grading, which is consistent with a risk-aversion tendency.