The phenomenon of missing doses in a cohort of HIV patients with good adherence to highly active antiretroviral therapy.

A self-administered questionnaire survey was conducted in a specialist HIV clinical service in Hong Kong. A total of 76 male Chinese patients who had been on highly active antiretroviral therapy for over one year were enrolled. All except one had undetectable viral load at the time of the assessment. Though a majority (76%) scored 100% in self-reporting adherence rating, one-third of these had in fact missed at least one dose in the preceding four-week period. Men having sex with men had a lower tendency of missing dose than heterosexuals (13.6% versus 42%, P=0.019). There was no association between missing doses and clinical staging or the regimens. The study revealed that missing doses may occur despite report of almost complete adherence, which, in the long run, could be a cause for concern.