Retention during the first year of HIV care and the effect of an interactive text-messaging service on patient engagement in care

Abstract: Background: Retention in HIV care is critical to ensure timely treatment initiation, viral suppression, reduced transmission, and to prevent AIDS-related deaths. Retention in care is low and falls short of the level needed to meet the UNAIDS 90-90-90 targets. There are few interventions designed to improve retention in HIV care and quantifying retention in care has been mostly limited to quantifying ‘retention in clinic’. ‘Retention in clinic’ accounts for those who return to the clinic at which they were originally enrolled but does not consider informal or formal transfers, which are common in sub-Saharan Africa. The overall aim of this thesis was to quantify retention in HIV care and to investigate whether the WelTel text-messaging intervention, previously found to improve antiretroviral therapy adherence, improved retention during the first year of HIV care. Ancillary studies using baseline data were also conducted as part of this thesis. Methods: Between April 2013 and June 2015, adults testing HIV-positive were recruited at two clinics in informal settlements in Nairobi, Kenya. Individuals ineligible for the trial because they did not meet phone-related trial eligibility criteria were invited to participate in a supplementary cohort study. In the trial, intervention arm participants received a weekly text-message and were asked to respond within 48 hours. The primary outcome was retention in care at 12-months (clinic attendance 10-14 months after the first visit). Participants who did not attend this 12-month appointment were traced and those confirmed active in care elsewhere were considered retained. All participants, both in the trial and cohort study, were followed for up to 14 months to quantify retention in care at one year. Baseline data for the entire study population were used to conduct additional studies on advanced HIV at presentation to care and a gender analysis of health-related quality of life at the time of a positive HIV test. Results: Of 700 individuals recruited for the trial, 349 were allocated to the intervention and 351 to the control arm. At 12 months, 79.4% (n=277/349) of intervention arm participants were retained in care compared to 81.2% (n=285/351) of control arm participants (risk ratio 0.98, 95% confidence interval [CI] 0.91 – 1.05). In the larger cohort study (n=775), 62.7% (95% CI 59.2% - 66.1%) of participants returned to the clinic for their 12-month appointment (retained in clinic) and 609 (78.6%, 95% CI 75.7% - 81.5%) were retained in care at any HIV clinic. In the first ancillary study, 248/753 (32.9%) participants presented to care with advanced HIV, 59.0% (146/248) of whom had been previously diagnosed with HIV. In the second ancillary study, the mean physical composite score was statistically significantly higher in women than men at the time of an HIV diagnosis (adjusted mean difference [AMD] 2.49, 95% CI 0.54 - 4.44). There was no significant difference between the genders in mental composite scores (AMD -0.99, 95% CI -2.71 - 0.73). Conclusions: Presentation to care with advanced HIV was primarily due to delayed diagnosis, rather than delayed linkage to care after diagnosis. Variation by clinic suggests that outreach and other community-based efforts may drive earlier testing and linkage to care. After receiving a positive HIV test, men and women had similar mental health scores, while women reported greater physical health. The weekly WelTel textmessaging service did not improve retention in early HIV care in this setting. Both in the trial and cohort study, retention in clinic substantially underestimated retention in care one year after presenting to care. While the proportion of patients retained in care was greater than expected, interventions to improve retention in care are needed to meet global targets to end the AIDS epidemic.