Effect Evaluation Of Antiretroviral Drugs To Prevent Mother To Child Transmission Of Aids

BackgroundAIDS has become a major public health problem worldwide, and HIV is a serious threat to the health of women and children. Therefore prevention of mother to child transmission of HIV is urgent. Prevention of mother-to-child transmission (PMTCT) provided to HIV infected pregnant women and their infants is a highly effective intervention and has huge potential to improve both maternal and child health. PMTCT interventions include antiretroviral drugs, safe delivery, formula feeding and other services. The effect of antiretroviral drugs to prevent mother to child transmission is particularly prominent. The provision of antiretroviral prophylaxis to both mother and child and avoidance of breastfeeding can reduce transmission from an estimated 30% to 35% with no intervention to around 1% to 2% with intervention in developed countries. Antiviral drugs including nucleoside reverse transcriptase inhibitors (NRTI), such as AZT and 3TC, and non-nucleoside reverse transcriptase inhibitors (NNRTI), such as NVP, whether used alone or in combination, can reduce the incidence of mother to child transmission. At present, research on the efficacy of anti-retroviral drugs on PMTCT is still being conducted.. There is also a lack of research assessing the effectiveness of combined versus single-drug regimens, Highly Active Antiretroviral Therapy (HAART) versus antiretroviral (ARV) prophylaxis, and duration of antiretroviral use. Evidence on these topics can be used to recommend the most effective and appropriate prevention of mother to child transmission ARV regimen.Objective1. To describe trends in PMTCT antiretroviral drug use over time;2. To compare use of antiretroviral drugs for prevention and treatment among HIV infected pregnant women;3. To determine the efficacy of antiretroviral drug regimens in PMTCT;4. To provide a scientific basis for national guidelines on antiretroviral regimens for PMTCT.MethodsThis study was a prospective observational cohort study. From 2005-2009,23 counties or districts with high HIV prevalence in the provinces of Xinjiang, Yunnan, Henan, Guizhou and Guangxi collected relevant information on HIV infected mothers and their infants and followed up through 18 months after delivery.As part of the national PMTCT initiative, pregnant women who were provided antenatal care in healthcare facilities in selected areas were offered HIV counseling and opt-out testing. HIV-positive pregnant women were offered prenatal care, antiretroviral drugs, safe midwifery, and formula feeding counseling services.HIV exposed infants were provided growth monitoring and follow-up services through 18 months of age. Infant HIV status was determined through early diagnosis of HIV before 6 months of age and HIV antibody testing at 12 and 18 months.Women were interviewed by trained investigators using a structured questionnaire. The questionnaire collected demographic characteristics and infant follow-up information, ARV use, mode of delivery and feeding mode. Antiretroviral drug regimens included sd-NVP, short-course AZT, combination ARV, prophylaxis regimen or highly active antiretroviral therapy (HARRT). Interviews were conducted in counseling rooms with the health care facilities while follow up interviews were held in the subjects'homes.Comparisons were assessed using the Pearsonχ2 test. Trends were evaluated using the Cochran-Mantel-Hanselχ2 test. Statistical analyses were performed with SAS v9 software.Results1. From 2005 to 2008 the percent of HIV infected pregnant women who received antiretroviral drugs was 77.13%,77.73%,78.26% and 84.20% respectively. The proportion of women receiving ARVs increased year by year (cmhx2=5.90, P=0.01). The proportion of HIV positive pregnant woman who recieved ART by year from 2005 to 2008 was 10.27%, 22.47%,40.85% and 67.56%. This also rose year by year (cmhχ2=232.06, P<0.0001). 2. Analyzing factors affecting ARV versus ART use, age, previous infection, accepting HIV antibody testing early in pregnancy and pre-test counseling were related to ARV use.3. Compared with the MTCT rate 11.27% of HIV infected pregnant women without ARVs, the MTCT among women who received ARVs declined to 4.38%(χ2=19.80, P <0.0001).4. Women who received sdNVP or short-course AZT had more risk of HIV transmission with 6.92% compared with two or triple combined antiretroviral regimens. Transmission-among those receiving two drug and triple ARVs was far lower at 3.02% and 3.20% respectively (χ2=8.04, P=0.02).5. Mother to child transmission was lower among those who took ARVs in pregnancy at 2.78%, compared with those who received ARVs at delivery at 6.81%. The MTCT among women who took ARVs regularly was lower than those who took ARVs less regularly (χ2=6.24, P=0.01)ConclusionAlthough the proportion of HIV-infected pregnant women who were provided antiretrovirals rose year by year, triple antiretroviral regimen coverage is still low and needs to be increased. Early and proper use of antiretrovirals does reduce mother to child transmission of HIV effectively. Regular antiretroviral use is particularly important. Doctors should place importance on HIV testing and providing ARVs during the first trimester. Efforts to improve compliance of long-term treatment should also be taken. It is suggested that antiretroviral use among HIV positive pregnant women could be improved by strengthening the HIV testing and counseling services provided in ANC settings. Promotion and application of HARRT should comply with regional characteristics. Meanwhile, clinical doctors should select appropriate modes of delivery dependent on the antiretroviral regimen used.