Novel Approaches for Visualizing and Analyzing Dose-Timing Data from Electronic Drug Monitors, or "How the 'Broken Window' Theory Pertains to ART Adherence".

Adherence to antiretroviral medications is usually expressed in terms of the proportion of doses taken. However, the timing of doses taken may also be an important dimension to overall adherence. Little is known about whether patients who mistime doses are also more likely to skip doses. Using data from the completed Adherence for Life randomized controlled trial, we created visual and statistical models to capture and analyze dose timing data collected longitudinally with electronic drug monitors (EDM). From scatter plots depicting dose time versus calendar date, we identified dominant patterns of dose taking and calculated key features [slope of line over calendar date; residual mean standard error (RMSE)]. Each was assessed for its ability to categorize subjects with 'sub-optimal' (<95 % of doses taken) using area under the receiver operating characteristic (AROC) curve analysis. Sixty eight subjects contributed EDM data, with ~300 to 400 observations/subject. While regression line slopes did not predict 'sub-optimal' adherence (AROC 0.51, 95 % CI 0.26-0.75), the variability in dose timing (RMSE) was strongly predictive (AROC 0.79, 95 % CI 0.62-0.97). Compared with the lowest quartile of RMSE (minimal dose time variability), each successive quartile roughly doubled the odds of 'sub-optimal' adherence (OR 2.1, 95 % CI 1.3-3.4). Patterns of dose timing and mistiming are strongly related to overall adherence behavior. Notably, individuals who skip doses are more likely to mistime doses, with the degree of risk positively correlated with the extent of dose timing variability.

Importance of dose timing to achieving undetectable viral loads.

Little is known about the importance of dose timing to successful antiretroviral therapy (ART). In a cohort comprised of Chinese HIV/AIDS patients, we measured adherence among subjects for 6 months using three methods in parallel: self-report using a visual analog scale (SR-VAS), pill count, and electronic drug monitors (EDM). We calculated two adherence metrics using the EDM data. The first metric used the proportion of doses taken; the second metric credited doses as adherent only if taken within a 1-h window of a pre-specified dose time (EDM 'proportion taken within dose time'). Of the adherence measures, EDM had the strongest associations with viral suppression. Of the two EDM metrics, incorporating dose timing had a stronger association with viral suppression. We conclude that dose timing is also an important determinant of successful ART, and should be considered as an additional dimension to overall adherence.

Barriers to adherence to antiretroviral medications among patients living with HIV in southern China: a qualitative study.

Although China's government is rapidly expanding access to antiretroviral therapy, little is known about barriers to adherence among Chinese HIV-infected patients, particularly among injection drug users. To better understand barriers to antiretroviral treatment adherence, we conducted a qualitative research study, using both focus group and key informant methods, among 36 HIV-positive men and women in Dali, in southwestern China. All interviews utilized semi-structured question guides and were conducted in Mandarin, audio-recorded and translated into English for analysis. The most commonly cited adherence challenges were stigma, including secondary stigma experienced by family members; mental health issues; and economic concerns, particularly related to finding and maintaining employment. Distinctive gender differences emerged, partly due to previous heroin use among male respondents. Optimizing adherence may require that antiretroviral therapy programs be linked to other services, including drug addiction treatment, mental health services and vocational treatment and support. HIV care and service providers and policy makers in China responsible for HIV treatment should be aware of these important barriers to adherence.

HIV and AIDS in the People's Republic of China: a collaborative review.

The number of individuals diagnosed with HIV in China has risen dramatically in the last two years coincident with increased awareness and an attitude change within government. UNAIDS has suggested that China could have 10 million HIV infected people by 2010. However, antiretroviral treatments and HIV testing are not yet widely available and infected individuals often live in remote areas. It is unlikely that cheaper, locally produced, generic antiretroviral formulations will be available in China in the near future. Consequently, alternative strategies to manage HIV infection are being considered including the use of hydroxyurea, chloroquine and traditional Chinese herbal medicines. It is recognized in China that prevention and educational strategies will need to be at the forefront of approaches to control this epidemic.

Feasibility and Acceptability of a Real-Time Adherence Device among HIV-Positive IDU Patients in China.

We collected data on feasibility and acceptability of a real-time web-linked adherence monitoring container among HIV-positive injection drug users (IDU) in China. "Wisepill" uses wireless technology to track on-time medication dosing. Ten patients on antiretroviral therapy (ART) at the Guangxi CDC HIV clinic in Nanning, China, used Wisepill for one ART medication for one month. We monitored device use and adherence and explored acceptability of the device among patients. Mean adherence was 89.2% (SD 10.6%). Half of the subjects reported a positive overall experience with Wisepill. Seven said that it was inconvenient, supported by comments that it was large and conspicuous. Five worried about disclosure of HIV status due to the device; no disclosures were reported. Twelve signal lapses occurred (5.4% of prescribed doses), of which one was due to technical reasons, nine to behavioral reasons (both intentional and unintentional), and two to unclear reasons. Although the technical components must be monitored carefully, and acceptability to patients presents challenges which warrant further exploration, the Wisepill device has potential for adherence interventions that deliver rapid adherence-support behavioral feedback directly to patients, including IDU. The use of wireless technology appears uniquely promising for providing time-sensitive communication on patient behavior that can be harnessed to maximize the benefits of HIV treatment.