我的生活+的主要目标之一是帮助人们预防新的HIV和其他STI,丙型肝炎和结核病病历的产生。

该应用程序有助于建立医生和HIV感染者之间的匿名沟通。 它可以让您创建简单易行的服药时间表,并设置隐藏和个性化的提醒。

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25 七月 2017, 18:35
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HIV Pre-Exposure Prophylaxis (PrEP) Online Course at Coursera Review. Day 18 of 42.

HIV Pre-Exposure Prophylaxis (PrEP) Online Course at Coursera Review. Day 18 of 42. - 图片 1

Couples, where one of the partners lives with HIV, are called ‘serodiscordant.’ In the eighteenth lesson of the PrEParing course, instructors offer to talk about the use of PrEP in such couples. The lecture “PrEP in Women and Serodifferent Couples” was read by Dr. Jennell Coleman, an OBGYN with expertise in reproductive infectious diseases.

Dr. Coleman spoke about HIV prevention for women living in serodiscordant couples.

For those who find it difficult to understand medical terms, let’s give an example:Ann is a 30 years-old woman; she does not have HIV and chronic diseases. Ann lives with a man Andrew, he is 37 years old, and he is HIV-positive. Doctors describe a couple of Ann and Andrew ‘serodiscordant’, indicating that people with different HIV status live together and, possibly, have a regular sex life.

There is a risk of HIV transmission for HIB-negative partner living in a serodiscordant couple, but medical knowledge in its current state can provide several ways to prevent the transmission of HIV from a man to a woman in a serodiscordant couple. One such method is PrEP.

Dr. Coleman begins his lecture estimating global trends of the HIV epidemic. 2,400 women become HIV-positive every day. In the United States, the picture is the following: risk of getting HIV among black women if four times more higher than the risk for white or Hispanic women.

There was one study that examined at this a little bit closer and enrolled about 2,000 women from five different cities in the US with a high prevalence of HIV. The majority were black, they were about 88%, 12% were Hispanic, and 8% were white. The incidence of HIV in that study was five times higher than the estimates of the American Center for Disease Control (CDC). It was almost close to incidence rates to particular Sub-Saharan African countries. So again, we know that in some populations in the US among women, some women are at risk for HIV infection.

The first studies of PrEP in women were conducted on antiretroviral agents being used topically, such as a gel with tenofovir and emtricitabine. A decline in HIV transmission in most of these studies was found, although the level of reduction appeared to be inadequate.

Epidemiologists have suggested that the low effectiveness of the first pilot programs of PrEP in women was associated with low adherence to drug intake. For oral forms of PrEP, researchers noted that women with lack of education could interrupt the course, believing that they do not have the risk of getting HIV. Another factor of low adherence was found in women who were in relationships with abusive partner, in such cases women often rely on the partner’s decision.

There are also biological factors that reduce the effectiveness of PrEP in women. Statisticians show a higher incidence of bacterial infections, STIs, among women involved in studies. The total area of rectal and vaginal mucosa is superior to that in men. The larger the area of mucosal membranes, the higher the risk of HIV transmission. Moreover, also seminal fluid can last for days inside the female genital tract after sexual intercourse. So, women are more at risk of HIV transmission than men in serodiscordant couples.

In previous “Pharmacokinetics and Pharmacodynamics” lecture instructor has already described the rate of tenofovir and emtricitabine distribution in the human body. They showed that in rectal mucosa PrEP reaches effective concentrations after seven days, when in vaginal and cervical mucosa not earlier than after 21 days.

Inflammatory processes in female genital tract and external genitalia also increase the risk of HIV transmission. Inflammation can be caused by a deficiency of hormones, STIs like syphilis or gonorrhea. The number of immune cells, such as CD4-lymphocytes, increases in the inflammation zone. These cells are excellent targets for HIV. Besides, inflammation disrupts the integrity of the mucous membrane. Therefore, the inflammatory process in the mucous membranes increases the risk of HIV transmission.

So going back to PrEP in women, there was a recent study that examined five clinical trials and noted again that three reported evidence of effectiveness and two didn’t. Researchers conducted additional calculations, regression analysis, to understand whether adherence affects the risk of HIV transmission in women. And it turned out that yes, it does. The higher the adherence to PrEP, the lower her risk of getting HIV.

After the objective evidence that the PrEP in women works was obtained, it remained to solve two priority tasks. The first is how health providers and PrEP consultants can help identify women who are at higher risk of getting HIV. The second is how a woman can understand on her own that the risk of getting HIV is high and it is worth contacting a PrEP provider.

In a recent study, the Center for Disease Control (CDC) estimated the number of people in the US indicated for prescribing PrEP. It turned out to be 1.2 million, where 624,000 of them were heterosexual men and 460,000 women.

It turns out that PrEP was prescribed only to one in 167 women compared to one in four to men from MSM group. So it is hard to develop methods for assessing how to identify a woman who should be prescribed PrEP.

Epidemiologists have investigated medical insurance databases in the United States. The results showed that in 2014 only in 3 percent of cases PrEP was prescribed to women. Dr. Coleman reminds that the number of new HIV cases in the US among men and females is the same. Hence, public health providers deliver insufficient attention to women.

Next, Dr. Coleman suggested looking at two cases from clinical practice and thinking about your choice.

Case 1

33 yo. HIV-negative who came to consultation for preconception counseling with her husband who is living with HIV. They want to have a biological child together. Her husband was compliant with his pill regimen and his visits to a doctor. He had been taking antiretroviral therapy for years and had an undetectable viral load. The woman had never been pregnant before and had never tried, because her partner was HIV-positive. Protocol for PrEP and preconception counseling recommends screen all patients for intimate partner violence, the result was negative.

Question: — will you prescribe PrEP to this woman?

Next, instructor talks in her lecture about a recent study looking at a general population of people living with HIV. It is interesting that every second person living with HIV lives in serodiscordant relationships and one in five lives with a partner of unknown HIV status. So, one can assume that between 50 and 70 percent of HIV-positive people live in couple with an HIV-negative partner. Researchers at the Johns Hopkins University have tried to estimate how many of these people live in heterosexual couples — there are about 140,000 couples in the United States, half of them wanted to have children. “So this highlights the importance of asking patients about their fertility desires and plans,” says Dr. Coleman.

Case 2

26 yo. healthy pregnant woman presented with her male partner for prenatal care on her 14th gestation week. This was her second pregnancy, she has performed test for HIV in initial prenatal labs and was HIV-negative. Her male partner spoke freely, he was not receiving antiretroviral therapy because he was homeless and was experiencing alcohol abuse, so his providers did not provided him any antiretroviral therapy. They both openly discussed that he could be physically abusive at times. The man stated he was trying to overcome such behavior, and the woman not ready to break the relationship.

Question: — will you prescribe PrEP to this woman?

So, pregnancy may be a time of enhanced risk of HIV acquisition.

 

It’s unclear whether or not this is biological, as a result of the pregnancy and immune changes, or is it behavioral, regarding the male partner having outside partners during the pregnancy. So, the series of studies confirm that the risk of HIV transmission from an HIV-positive man to an HIV-negative woman during pregnancy increases.

The increased risk of HIV transmission from mother to fetus or child is also well studied in cases when a healthy mother receives HIV from a partner during pregnancy or breastfeeding. Epidemiologists conducted two studies, one at the Department of Health of New York, and the second at the US CDC. Both studies show that one in seventy women (1.4 percent) is receiving HIV during these periods. In such cases, the risk of HIV transmission to a child is very high, because the mother does not immediately recognize that she has become HIV-positive. The virus in the mother’s blood reproduces and can pass to the baby’s organism during pregnancy, childbirth or through breast milk during breastfeeding.

A course participant could immediately raise the question:

“And what about PrEP for pregnant women?”

This issue has been discussed for the past five years, but so far there has not been a single randomized clinical trial in which researchers could have studied this issue in detail. But there are indirect data from studies that indicate the safety of PrEP during early pregnancy. PrEP was not the cause of miscarriage, delayed fetal growth, or significant differences in children among mothers who took PrEP during early pregnancy.

Other studies that examined women living with HIV or hepatitis B also failed to show an increase in risks of fetal defects, developmental delays, premature births caused by PrEP pills. There was one small study in which mothers who received PrEP or an antiretroviral therapy regimen containing Truvada were observed. The report on this study showed that children might lag somewhat behind in growth and weight, they may have decreased bone density at birth. Such children did not differ from their peers at the age of two.

And recently World Health Organization put out a systematic review, and its statement was that it does not appear to be a safety related rationale for prohibiting PrEP during pregnancy or lactation. Also, there is no evidentiary logic in the ban on a continuation of PrEP for pregnant women. In other words, WHO did not find any evidence in favor of the risk of PrEP for pregnant women and their children. Moreover, prescribing PrEP to a woman will allow her to breastfeed an infant. There are some controversial opinions among child psychologists that breastfeeding better affects the formation of a human personality. There are also opinions among pediatric immunologists that effects of breastfeeding are better than lactating with milk formula. The issue requires further study, systematic reviews, and evidence-based practices.

Next, we have Case 3, and this is more a typical example that Dr. Coleman has in her practice in Baltimore, USA.

Case 3

HIV-negative 36 yo. woman visited to OBGYN for routine annual examination. She have lasting relationships with two male sexual partners, one of them is her main partner and the second is a casual partner. She did not know the HIV status of her partners, but she assumed that they both were HIV-negative. Her tests for trichomonas and gonorrhea STIs were positive.

Question: — will you prescribe PrEP to this woman?

Next, Dr. Coleman moves to clinical guidelines on prescribing PrEP to women. In the United States, there are clinical guidelines issued by CDC and the American College of Obstetrics and Gynecology:

  • The CDC recommends heterosexual women to start PrEP in cases where they are in a permanent relationship with an HIV-positive partner. In case a woman does not have a permanent partner, risk factors are taken into account: the number of sexual partners, the history of STI diagnoses, commercial sex work, etc.
  • The American College of OBGYN offers an expanded list, recommending to prescribe PrEP for women living in an area with a high HIV prevalence, or engaged in social work with homeless, prisoners, commercial workers; to women who abuse alcohol. For women who are directly or indirectly at risk of HIV transmission, PrEP provider is recommended at least to have a conversation with them.

There aren’t too many demonstration projects in the US among women in PrEP. For example, researchers studied the effects of PrEP on 27 women from two American cities. 67 percent of these women have already taken PrEP before, during and after pregnancy. The study has shown that PrEP was safe during pregnancy. After delivery, half of observed women disappeared from the field of view of the researchers. So, it is important to establish feedback with such women; perhaps electronic feedback can help, such as a mobile application for HIV-positive people Life4me+.

In the future, says the instructor, new methods of PrEP will be possible, which can be taken less often than once a day, such as intravaginal rings, disposable films, PrEP injections, and others. It is interesting that in that novel ways of delivery it is possible to combine PrEP with contraception.

At the end of the lecture, Dr. Coleman gave some follow up on the cases.

In the first case, a couple was planning a pregnancy, which was offered PrEP, but the woman refused. As a result, the couple tried to conceive the child naturally, they succeeded after the first try, “which was like spectacular” and the woman remained HIV-negative and she delivered a healthy baby.

In the second case, there was a pregnant HIV-negative woman attended for consultation with an HIV-positive partner who did not take ART, a classic case. So, the woman got HIV from her partner during breastfeeding and, unfortunately, the child subsequently also turned out to be HIV-positive.

In the third case, this is the most frequent scenario, an HIV-negative woman came for a routine annual examination, she had bacterial infections, and she reported having several sexual partners whose HIV status is unknown. She was offered PrEP, she refused, because she believed that there was no risk. This woman did not appear at the consultant. But the steps were performed correctly — consultant told the woman about the risk of HIV, offered PrEP and explained what it is. Now the woman is aware of PrEP and can ask it from her doctor in the future.

The review is completed for today, if the information you read in the article seems to be important — please, share it on a social network or send it to friends by email or via Whatsapp, Viber, Telegram or another messenger.

If you have not already signed up for the PrEParing course on the Coursera platform, it’s never too late to do it, just follow the link https://www.coursera.org/learn/prep.

Stay with us and stay healthy!

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