The CAP Study
Women with a history of pre-eclampsia in their most recent pregnancy who agree to participate, receive calcium 500mg daily or placebo from enrolment until they become pregnant, and up to 20 weeks of pregnancy. The primary outcome is pre-eclampsia.
The graph above shows that we stopped recruitment in September 2016, and since February 2017 have been discontinuing the participation of non-pregnant women. Of the 587 completed pregnancies, 77 terminated before 24 weeks and 510 after 24 weeks. There are 42 women with on time visits and 13 with delayed visits. We expect to achieve our target of 540 pregnancies beyond 24 weeks.
Discontinuation of non-pregnant participants:
A novel feature of the CAP study has been the need to discontinue participants who have not become pregnant in an ethical way. We thank Ana Pilar Betran for researching and putting together a carefully considered process. This included the following guidelines for the study staff, and a letter to non-pregnant participants:
Steps to discontinue non-pregnant women
- Discontinue the women in a face-to-face interview. Ideally, you could discontinue each woman in her next PPV appointment. Do not resupply tablets in the discontinuation visit
- Print the explanatory letter (translated into local languages if necessary) to be given to the woman so she can take it home.
- Do a pregnancy test to make sure that she is not pregnant. If the test is negative, proceed to discontinue the participant. If the test is positive, continue the women in the study as per standard procedures of the trial.
- Explain that the trial has finished and that she will no longer need to come for the trial visits. Thus, she will no longer receive the tablets that she received since she entered the trial.
- Explain that we are giving her an explanatory letter to take home and read, and she can give the letter to her regular healthcare provider.
- Explain that she should continue her regular heath care with her healthcare provider, as she was during the study.
- If you think it is appropriate and possible, you may ask her if she would like you to schedule an appointment with a fertility clinic.
- Explain that we will call her in 6 weeks to check on her health as we have been doing during the study (the inter-visits phone calls).
- If the woman asks about continuing supplementation (e.g. buying calcium or other supplements in the pharmacy), ask her to contact her regular healthcare provider and discuss with him/her.
- Ask her if she wants the study finding be communicated to her and if so, how we should do this (e.g. letter, email, telephone).
- If the participant shows interest in knowing if they have been in the intervention arm or a control arm of the study, explain that breaking the code at this moment is not possible. Later when the summary results are available, this information could be made available to individual participants if they request it.
- Allow participants to ask you in person any questions they may have.
Discontinuation letter to participants:
Dear CAP study Participant,
This letter is to tell you that the CAP Study is drawing to a close. In this study you were randomly allocated (i.e. like spinning a coin) to tablets with calcium or to similar tablets but without calcium. Neither you nor we know which treatment you are receiving during your participation in the study. Our objective was to measure the effect of calcium on blood pressure and health, and the health and growth of the baby of those women who fell pregnant during the study period.
Closure of the trial means that you will no longer need to come for the trial visits and you will no longer receive the tablets that you have had since you entered the trial. You should now continue your regular health care with your healthcare provider as you were also doing during the study. Please, share this letter with your healthcare provider. You should also continue your regular life without concern for not continuing the tablets. We will call you in six weeks to check on your health.
We expect to have the summary finding of the study near the end of 2017. If you wish to know the results, please let us know how you would like us to tell you about them: by a letter, email or telephone call.
We would like to thank you for your participation, time and interest on this CAP Study. Your participation has been an important contribution to advance research and improve healthcare of pregnant women in the future.
The RCOG 2017 conference in Cape Town (20-22 March 2017) provided the opportunity for Stephen Munjanja, Sarah Manyame, Jim Roberts and Justus Hofmeyr to meet and discuss the urine biochemical studies of the calcium/creatine ratio and protein creatinine ratio, which were planned as part of this study. The analysis of Zimbabwean samples will be done by Sarah in Harare, and the rest by the University of Stellenbosch biobank facility in Tygerberg, Cape Town. The studies will be complemented with a case-control study of urinary predictors of pre-eclampsia done in Harare, which will be the basis of Sarah’s PhD. Sarah and Jim met with Carmen Swanepoel of Stellenbosch University to discuss using other CAP urine samples as a validation group in a collaboration between Sarah and Carmen.
We have submitted for publication the manuscript for a paper: Nutritional assessment of Pregnant Women from South Africa and Zimbabwe participating in the Calcium and Preeclampsia trial by Gabriela Cormick et al.