Sexual behaviors during antiretroviral therapy among HIV-infected patients, Thailand

An increasing trend in sexual risk behavior has occurred in the era of antiretroviral therapy (ART) in Thailand. This study was conducted to identify sexual risk behavior and examine relationships between unprotected sex and CD4 levels among HIV-infected patients receiving ART in the National Antiretroviral Program. A cross-sectional survey was conducted in 460 HIV-infected patients age 18-49 years who visited the out-patient clinic of Bamrasnaradura Infectious Diseases Institute in February 2006 by using a standardized self-administered questionnaire. The results show that 60.4% of participants were men. The median most recent CD4 cell count during the prior 6 months was 261 cells/mm3. Twenty-three percent of the participants who had no sexual activity after they knew their HIV positive status started having sex again after receiving ART with a 12-week median duration period from starting ART to having first sex. There was a significant difference between the number of those having sexual activity before and after starting ART (p-value=0.013). Fifty-six percent of participants had sex during the previous 6 months. Of these, 26.5% had sex with commercial partners and 28.4% with non-regular partners. Inconsistent condom use, with commercial partners or non-regular partners, in females (35.3-36.8%) was higher than in males (7.8-11.1%). Participants with a known HIV-negative regular partner were 0.25 times more likely to have unprotected sex than those with a known HIV-positive regular partner (adjusted OR, 0.25; 95%CI, 0.09-0.73). No association between unprotected sex and CD4 levels was found. The findings support the need for reinforcing risk reduction programs among HIV-infected persons, particularly couple counseling, and promoting awareness of risk of acquirring sexually transmitted infections and drug-resistant strains of HIV.     

Error variability affects the after effects following motor learning of lateral balance control during walking in people with spinal cord injury

People with incomplete spinal cord injury (iSCI) usually show impairments in lateral balance control during walking. Effective interventions for improving balance control are still lacking, probably due to limited understanding of motor learning mechanisms. The objective of this study was to determine how error size and error variability impact the motor learning of lateral balance control during walking in people with iSCI. Fifteen people with iSCI were recruited. A controlled assistance force was applied to the pelvis in the medial‐lateral direction using a customized cable‐driven robotic system. Participants were tested using 3 conditions, including abrupt, gradual, and varied forces. In each condition, participants walked on a treadmill with no force for 1 min (baseline), with force for 9 min (adaptation), and then with no force for additional 2 min (post‐adaptation). The margin of stability at heel contact (MoS_HC) and minimum value moment (MoS_Min) were calculated to compare the learning effect across different conditions. Electromyogram signals from the weaker leg were also collected. Participants showed an increase in MoS_Min (after effect) following force release during the post‐adaptation period for all three conditions. Participants showed a faster adaptation and a shorter lasting of after effect in MoS_Min for the varied condition in comparison with the gradual and abrupt force conditions. Increased error variability may facilitate motor learning in lateral balance control during walking in people with iSCI, although a faster learning may induce a shorter lasting of after effect. Error size did not show an impact on the lasting of after effect.