Browsing by Author "Amorim, Gustavo"

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    Contraceptive implant use duration is not associated with breakthrough pregnancy among women living with HIV and using efavirenz: a retrospective, longitudinal analysis
    (Wiley, 2022) Stalter, Randy M.; Amorim, Gustavo; Mocello, A. Rain; Jakait, Beatrice; Shepherd, Bryan E.; Musick, Beverly; Bernard, Caitlin; Bukusi, Elizabeth A.; Wools-Kaloustian, Kara; Cohen, Craig R.; Yiannoutsos, Constantin T.; Patel, Rena C.; Implant/Efavirenz Study Group; East Africa IeDEA regional consortium; Biostatistics, School of Public Health
    Introduction: Contraceptive implants containing etonogestrel and levonorgestrel have emerged as popular contraceptive options among women in areas of high HIV burden in sub-Saharan Africa. However, recent pharmacokinetic data have shown drug-drug interactions between implants and efavirenz-containing antiretroviral therapy (ART), reducing the effectiveness of the implants. Here, we evaluated pregnancy incidence in 6-month intervals following implant initiation among women using efavirenz and contraceptive implants to assess whether the risk of breakthrough pregnancy is higher after specific periods of implant use. Methods: We used data from a retrospective longitudinal analysis of women living with HIV ages 18-45 years in western Kenya who attended HIV-care facilities between 2011 and 2015. We used Cox proportional hazard models to compute hazard ratios (HRs) for breakthrough pregnancy by implant type and ART regimen. Depending on the model, we adjusted for socio-demographic and clinical factors, programme, site and interaction between calendar time and ART regimen. We utilized inverse probability weights (IPWs) to account for three sampling phases (electronic medical record [EMR], chart review and phone interview) and calculated overall parameter estimates. Results: Women contributed 14,768 woman-years from the largest sampling phase (EMR). The median age was 31 years. Women used etonogestrel implants for 26-69% of the time and levonorgestrel implants for 7-31% of the time, depending on the sampling phase. Women used efavirenz, nevirapine or no ART for 27-33%, 40-46% and 15-26% of follow-ups, respectively. When combining sampling phases, there was little evidence to suggest that the relative hazard of pregnancy among efavirenz-containing ART users relative to nevirapine-containing ART changed with length of time on implants: IPW-adjusted HR of 3.1 (CI: [1.5; 6.4]) at 12 months, 3.4 (CI: [1.8; 6.3]) at 24 months, 3.8 (CI: [1.9; 7.7]) at 36 months and 4.2 (CI: [1.6; 11.1]) at 48 months (interaction p-value = 0.88). Similarly, no significant change in HRs over time was found when comparing women not using ART to nevirapine-containing ART users (interaction p-value = 0.49). Conclusions: We did not find evidence to suggest implants being more fallible from drug-drug interactions with efavirenz at later time intervals of implant use. Thus, we would not recommend shortening the duration of implant use or replacing implants sooner when concomitantly used with efavirenz.
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    The effect of a Mentor Mothers program on prevention of vertical transmission of HIV outcomes in Zambézia Province, Mozambique: a retrospective interrupted time series analysis
    (Wiley, 2022) Carlucci, James G.; Yu, Zhihong; González, Purificación; Bravo, Magdalena; Amorim, Gustavo; das Felicidades Cugara, Cristina; Guambe, Helga; Mucanhenga, Jaime; Silva, Wilson; Tique, José A.; Sardella Alvim, Maria Fernanda; Graves, Erin; De Schacht, Caroline; Wester, C. William; Pediatrics, School of Medicine
    Introduction: Mentor Mothers (MM) provide peer support to pregnant and postpartum women living with HIV (PPWH) and their infants with perinatal HIV exposure (IPE) throughout the cascade of prevention of vertical transmission (PVT) services. MM were implemented in Zambézia Province, Mozambique starting in August 2017. This evaluation aimed to determine the effect of MM on PVT outcomes. Methods: A retrospective interrupted time series analysis was done using routinely collected aggregate data from 85 public health facilities providing HIV services in nine districts of Zambézia. All PPWH (and their IPE) who initiated antiretroviral therapy (ART) from August 2016 through April 2019 were included. Outcomes included the proportion per month per district of: PPWH retained in care 12 months after ART initiation, PPWH with viral suppression and IPE with HIV DNA PCR test positivity by 9 months of age. The effect of MM on outcomes was assessed using logistic regression. Results: The odds of 12-month retention increased 1.5% per month in the pre-MM period, compared to a monthly increase of 7.6% with-MM (35-61% pre-MM, 56-72% with-MM; p < 0.001). The odds of being virally suppressed decreased by 0.9% per month in the pre-MM period, compared to a monthly increase of 3.9% with-MM (49-85% pre-MM, 59-80% with-MM; p < 0.001). The odds of DNA PCR positivity by 9 months of age decreased 8.9% per month in the pre-MM period, compared to a monthly decrease of 0.4% with-MM (0-14% pre-MM, 4-10% with-MM; p < 0.001). The odds of DNA PCR uptake (the proportion of IPE who received DNA PCR testing) by 9 months of age were significantly higher in the with-MM period compared to the pre-MM period (48-100% pre-MM, 87-100% with-MM; p < 0.001). Conclusions: MM services were associated with improved retention in PVT services and higher viral suppression rates among PPWH. While there was ongoing but diminishing improvement in DNA PCR positivity rates among IPE following MM implementation, this might be explained by increased uptake of HIV testing among high-risk IPE who were previously not getting tested. Additional efforts are needed to further optimize PVT outcomes, and MM should be one part of a comprehensive strategy to address this critical need.
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    Pregnancies among women living with HIV using contraceptives and antiretroviral therapy in western Kenya: a retrospective, cohort study
    (BMC, 2021-08-13) Patel, Rena C.; Amorim, Gustavo; Jakait, Beatrice; Shepherd, Bryan E.; Mocello, A. Rain; Musick, Beverly; Bernard, Caitlin; Onono, Maricianah; Bukusi, Elizabeth A.; Wools-Kaloustian, Kara; Cohen, Craig R.; Yiannoutsos, Constantin T.; Biostatistics, School of Public Health
    Background: Preventing unintended pregnancies is paramount for women living with HIV (WLHIV). Previous studies have suggested that efavirenz-containing antiretroviral therapy (ART) reduces contraceptive effectiveness of implants, but there are uncertainties regarding the quality of the electronic medical record (EMR) data used in these prior studies. Methods: We conducted a retrospective, cohort study of EMR data from 2011 to 2015 among WLHIV of reproductive age accessing HIV care in public facilities in western Kenya. We validated a large subsample of records with manual chart review and telephone interviews. We estimated adjusted incidence rate ratios (aIRRs) with Poisson regression accounting for the validation sampling using inverse probability weighting and generalized raking. Results: A total of 85,324 women contributed a total of 170,845 women-years (w-y) of observation time; a subset of 5080 women had their charts reviewed, and 1285 underwent interviews. Among implant users, the aIRR of pregnancy for efavirenz- vs. nevirapine-containing ART was 1.9 (95% CI 1.6, 2.4) using EMR data only and 3.2 (95% CI 1.8, 5.7) when additionally using both chart review and interview validated data. Among efavirenz users, the aIRR of pregnancy for depomedroxyprogesterone acetate (DMPA) vs. implant use was 1.8 (95% CI 1.5, 2.1) in EMR only and 2.4 (95% CI 1.0, 6.1) using validated data. Conclusion: Pregnancy rates are higher when contraceptive implants are concomitantly used with efavirenz-containing ART, though rates were similar to leading alternative contraceptive methods such as DMPA. Our data provides policymakers, program staff, and WLHIV greater confidence in guiding their decision-making around contraceptive and ART options. Our novel, 3-phase validation sampling provides an innovative tool for using routine EMR data to improve the robustness of data quality.