Medication adherence to antiretroviral therapy among newly treated people living with HIV

Antiretroviral therapy (ART) has proven to be the most effective treatment method for people living with HIV [1, 2], its effectiveness critically depends on the extent of individual medication adherence [3‐5]. When the rate of adherence to medication is as high as 95%, the viral suppression rate approaches 78%. However, when the rate of adherence is reduced to 80%, there is a dramatic reduction in the viral suppression rate, which can be as low as 20%. The adherence rate of medication should be maintained at 95% or above to optimize antiviral outcomes and enhance viral suppression [6, 7]. Additionally, failure to maintain the blood concentrations of the medications is a common and serious problem, data indicated that dosing time adherence was significantly associated with lower viral load, and that was also associated to elevated CD4 cell count [8, 9]. Poor adherence to medication has been confirmed to be an important risk factor for the emergence of drug-resistant HIV strains, which can be transmit to others [10, 11]. Poor medication adherence not only endangers individual health but also increases of transmission with detectable viral loads, brings difficulties in treatment, leading to severe public health problems.

The “Four Frees and One Care” policy was promulgated in China in 2004. As a result, more than 420,000 AIDS patients received antiretroviral therapy by June 2016 [12]. HIV/AIDS is becoming a manageable chronic condition, and adherence to ART, especially adherence to medication, is the focus of many researchers. Medication adherence is defined as taking all medications at the appropriate time with the appropriate dosage as prescribed by the physician [13, 14]. Although there is no standard method of measurement, self-report questionnaires are widely used due to their simplicity and validity. Their results are consistent with objective measurement methods, such as electronic drug concentration monitoring and plasma drug concentration monitoring [15]. Zhou et al. conducted a meta-analysis of medication adherence among patients receiving antiviral therapy in China from 1985 to 2015 [16] and found that the 90% medication adherence rate was 77.61%, which was lower than the rates reported by similar studies conducted in other countries [17‐19]. This finding suggested a greater need to pay attention to this group of people in China.

Adherence to medication is a complicated behavior that is affected by disease-related, cognitive and psychological, and provider-related factors [17, 20]. Disease-related factors include symptoms [19], the disease course [21, 22], and side effects [22]. Cognitive and psychological factors include self-efficacy [23], the depression or anxiety status [24], and knowledge of medication [17]. Provider-related factors include patient-provider relationships [25], the provision of limited instructions [21, 26], and low-quality services [26].

Previous studies had several limitations in assessing adherence to medication. First, the assessment was based solely on the self-reported quantity of drugs taken by the patients but not on the timing of drug intake. In addition, neglect of the time difference of drug intake may lead to an overestimation of adherence [15]. Second, the stage of ART was not specified. As the treatment duration progresses, the probability of non-adherence increases [27]. Therefore, high priority must be given to the assessment of adherence behavior as well as any necessary intervention for non-adherence during the early stages of treatment.

Optimizing adherence, especially in the early stages of treatment, is crucial to ensure long-term immunological and virological success [27]. For people living with HIV who have newly initiated antiretroviral therapy, accurately evaluating their medication adherence and identifying the factors associated with adherence can help providers to predict their prognosis and adopt timely interventions to facilitate and maintain the optimum effects of antiviral therapy. Given the above considerations, this study aimed to investigate medication adherence with respect to both quantity and timing and the factors related to adherence among people living with HIV with newly initiated antiretroviral therapy and to provide evidence for formulating individualized interventions to improve treatment outcomes.

The rate of dosage adherence among newly received antiretroviral therapy (within 3–6 months) was 87.0% in this study. This rate was higher than the result obtained by Wang [34], who reported 78.9% dosage adherence rate among patients with HIV infections with an average treatment duration of 17.7 months but was lower than the results of Xiao [35], who reported a 96.6% dosage adherence rate. This difference might due to the different characteristics and treatment cascades of the samples, since we compared the rate using the same operational definitions of adherence behavior within the studies. The rate of taking the medicine within the prescribed time was 87.4%, which was higher than the rate indicated by Gill [29], who reported 47.8% dosing time adherence rate in the past months. This might due to the inconsistent time of medication length, the medication adherence would decrease with the medication time increasing [7]. It is suggested that more attention should be paid to the adherence of newly treated people living with HIV.

The univariate analysis revealed that participants with positive anxiety symptoms, positive depression symptoms and AIDS-related symptoms had a higher tendency for poor adherence, which were consistent with previous studies [19, 23, 26]. Globally, numerous studies have demonstrated that people living with HIV are vulnerable to psychological problems [24, 36‐39]. This group faces a high risk of mental health problems, but the psychosocial needs of HIV-positive individuals remain largely unaddressed in China [40]. The diagnosis of HIV status is a negative life event that results in negative psychological reactions, such as depression, anxiety and suicidal ideation [38, 41, 42]. Newly treated people living with HIV, especially those with AIDS-related symptoms, not only have to accept the fact of chronic condition, but also have to comply with complex medication regimens, which usually leads to increased symptoms of anxiety and depression. Additionally, participants with positive anxiety and depression may be more likely to have physiological symptoms that are attributed to the side effects of the antiviral regime [36, 43]. In the final model, this study did not demonstrate an association between anxiety and medication adherence (although 64.3% of the participants had anxiety symptoms, and 14.0% had severe anxiety symptoms). This result might due to the relatively short follow-up duration of the antiviral therapy for the study sample. Anxiety might worsen with a prolonged treatment time and decreased physical functioning of the patients, eventually resulting in adverse influences on medication adherence behavior [44]. Future interventions to facilitate patients’ adherence to antiretroviral therapy should pay close attention to their emotional health and changes in their emotional health over time. Furthermore, effective psychological coping strategies must be provided for this group.

Participants who refused to disclose their HIV status had poor adherence, which was consistent with previous studies [45].The reason may be that non-disclosure impeded them from obtaining social support. Patients with lower social support were more inclined to show poor adherence [46]. In this study, the positive rates of depression among those who refused to disclose their HIV status were higher than those of the disclosers, this also might cause the negative association between non-disclosure and adherence. In addition, participants who did not disclose their HIV status to others put more pressure on themselves in terms of taking regular medication [47], which might have led to missing dose intentionally especially for those living with others. We can reasonably assume that self-discrimination and fear of the deterioration of the relationship may have interfered with their disclosure to others, which in turn negatively affected their adherence. Thus, adherence-enhancing interventions for people living with HIV should consider incorporating psychosocial coping strategies, including providing assistance for disclosure to supportive others, improving their utilization of social support from their surroundings, and developing practical tips on how to keep their privacy while taking medication in the right amount at the right time in different situations may also be an important approach.

One-sixth of the participants reported suboptimal medication adherence within the first 6 months. Factors associated with poor adherence included non-disclosure of their HIV status, had positive depression. Tailored interventions, such as assistance with an appropriate disclosure process and effective medication reminder strategies involving family or other cohabitants in the psychosocial support program, should be implemented to improve medication adherence during established ART.