Adherence support needed during pregnancy

Adherence to antiretrovirals among HIV-positive women is far from optimal during pregnancy and falls further in the months after delivery, according to a study reported in the August 1^st edition of the Journal of Acquired Immune Deficiency Syndromes. Importantly, pregnant women with perfect adherence had lower viral loads than those who did not, so the US researchers conclude that interventions to improve adherence are needed in this group.

The short- and long-term success of antiretroviral therapy is directly related to levels of adherence to medication regimes. Antiretroviral treatment is recommended for pregnant women diagnosed with HIV in order to reduce mother-to-child HIV transmission and when needed, for the mother's health. Poor adherence to treatment can lead to increased risk of transmission to the child, development of viral resistance to treatment, and transmission of drug-resistant virus to the child.

Self-reported adherence rates were assessed in HIV-positive pregnant women and mothers up to 14 days after delivery who were enrolled in the Pediatric AIDS Clinical Trials Group Protocol 1025 from August 2002 to July 2005. Follow-up continued until 48 weeks after delivery. All participants were on tablet formulations and completed at least one self-assessment on adherence. Perfectly adherent subjects reported no missed doses four days before their study visit. Participants were also asked about the length of time since they last missed a dose.

Of 519 eligible women, 90% were enrolled before delivery. However, after delivery an increasing number of women did not complete the study forms on adherence, usually citing insufficient time, and these reports were scored as missing. The authors acknowledge that this study design may have led to underestimates of adherence. This is of concern since, among the 445 pregnant subjects receiving antiretrovirals and with self-report adherence forms completed, only 75% reported perfect adherence during the four days before their study visit nearest to but before delivery. The majority (53%) reported that the last time they had missed any dose was more than 3 months before the study visit.

Pregnant subjects with perfect adherence had lower viral loads than those who reported missing doses. The odds of perfect adherence were significantly higher for women who initiated antiretrovirals during pregnancy (p

Adherence rates significantly decreased six, 24, and 48 weeks after delivery (65%, 64%, and 66%, respectively (p

Thus, the team concludes that participants that do not have favourable characteristics associated with good adherence may need additional support with their medications. Future studies should further investigate tools for depression screening, ascertain the role of medication-related toxicities and the usefulness of support networks on adherence; and monitor the consequences of poor adherence on pregnancy outcomes, rates of mother-to-child transmission, and the development of viral resistance.