LETTERS TO THE EDITOR
Diagnosis, Evaluation, and Management of the Hypertensive Disorders of Pregnancy: Executive Summary To the Editor: In this comprehensive new SOGC Guideline1 I was surprised to see that methyldopa and (to some extent) clonidine are recommended as “alternative” oral therapeutic agents for the treatment of severe hypertension. While the immediaterelease nifedipine capsule has an onset of action approximately 20 minutes after administration and oral labetalol 20 minutes to two hours (peak effect 1 to 4 hours), the onset of action of oral methyldopa is four to six hours and immediate-release clonidine 30 minutes to one hour (peak effect 2 to 4 hours).2 While this is the executive summary (23 pages!) and it does not contain discussion on treatment, it is widely recognized that severe hypertension (defined in this guideline as a systolic blood pressure > 160 mmHg or a diastolic pressure > 110 mmHg) is associated with an increased risk of severe morbidity and mortality and should be controlled rapidly. Given this, I question the wisdom of “recommending” treatment that may take up to six hours to have a clinical effect. I trust that the diagnostic criteria for severe hypertension will be more fully discussed in the main document, since at least one well-quoted case series reports four of 24 peripartum strokes occurring with maternal systolic blood pressures of between 155 and 160 mmHg.3 Finally, I would like to suggest that in this electronic age future SOGC guidelines be circulated to the membership in draft form, so that all interested parties have a chance to review and comment before formal publication. David Somerset, FRCSC, FRCOG, FRANZCOG Departments of Obstetrics & Gynaecology and Radiology, University of Calgary, Calgary AB
REFERENCES 1. Magee LA, Pels A, Helewa M, Rey E, von Dadelszen P; SOGC Hypertension Guideline Committee. Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy: executive summary. SOGC Clinical Practice Guideline No. 307, May 2014. J Obstet Gynaecol Can 2014;36(5):416–38. 2. Drug Information (Lexicomp). UpToDate. Waltham, MA. Available at: http://www.uptodate.com/home/drugs-drug-interaction. Accessed May 6, 2014.
3. Martin JN Jr, Thigpen BD, Moore RC, Rose CH, Cushman J, May W. Stroke and severe preeclampsia and eclampsia: a paradigm shift focusing on systolic blood pressure. Obstet Gynecol 2005;105(2):246. J Obstet Gynaecol Can 2014;36(7):575
In Response To the Editor: We thank Dr Somerset for his comments. To clarify, the new Canadian guidelines have been published in two documents: an executive summary published in JOGC1 and a full-text, open-access version in Pregnancy Hypertension.2 The latter contains everything that is in the JOGC version, plus additional text and references for all sections. This arrangement was struck to balance the needs of the SOGC membership and the space constraints of the Journal. The link to the open access Pregnancy Hypertension document can be made by clicking on the link within the abstract of the document in JOGC. We also thank Dr Somerset for highlighting the critical issue of treatment of severe hypertension (≥ 160 mmHg systolic and/or ≥ 110 mmHg diastolic). This is discussed in detail beginning on page 119 of the Pregnancy Hypertension document.2 Strong recommendations (grade 1-A) are made for the use of parenteral labetalol, parenteral hydralazine, and oral nifedipine capsules for severe hypertension. Oral methyldopa and oral clonidine are suggested as alternatives, and were given lower ratings for quality of evidence and strength of recommendation (I-B and III-B, respectively). First, inclusion of oral agents for treatment of severe hypertension in the recommendations is aimed at getting severe hypertension treated, and treated more quickly in women cared for outside well-resourced facilities, be they rural health units or doctor’s offices where parenteral therapy and monitoring are not possible and transfer to hospital can take a few hours.3 Second, Dr Somerset raises the issue of how quickly severe hypertension must be treated. Most cases are without symptoms and present as part of a “hypertensive urgency”2; therefore, the severe hypertension can be managed over hours rather than minutes. Finally, we agree with Dr Somerset’s pharmacokinetic parameters for oral agents, and would add that the effect of oral nifedipine capsules peaks at one to four hours. The 2010 NICE guidelines from the United Kingdom list oral labetalol (200 mg) as one of the agents of first choice for severe hypertension in pregnancy.4 In the only relevant randomized controlled trial, oral methyldopa (250 mg) and labetalol (100 mg) JULY JOGC JUILLET 2014 l 575
LetterS to the Editor
were each effective in approximately 50% of women with severe hypertension, compared with > 80% effectiveness using nifedipine in other trials.5 Our perspective is that this therapeutic strategy is a reasonable alternative to providing nothing at all. We are conducting an ongoing trial of oral methyldopa versus nifedipine capsules versus labetalol that should help to clarify this issue. We cannot comment on the official SOGC policy on peer review. However, what we can say is that from January 2013 to January 2014, our Canadian Hypertensive Disorders of Pregnancy Working Group responded to three full rounds of peer review from the Hypertension Guideline Committee, the Maternal Fetal Medicine and Family Physician Advisory Committees, and the Executive and Council of the SOGC. Of course, we are more than happy to respond to questions and/or concerns from the membership as we move forward together in practice and in research. Laura A. Magee, MD, FRCPC Departments of Medicine and Obstetrics and Gynaecology, School of Population and Public Health, and Child and Family Research Institute, University of British Columbia, Vancouver BC Anouk Pels, MSc Amsterdam, The Netherlands Michael Helewa, MD, FRCSC Department of Obstetrics, Gynecology and Reproductive Sciences, University of Manitoba, Winnipeg MB Evelyne Rey, MD, MSc Department of Obstetrics and Gynaecology and Research Centre, CHU Sainte-Justine, University of Montreal, Montreal QC Peter von Dadelszen, MB ChB, DPhil, FRCSC Department of Obstetrics and Gynaecology, School of Population and Public Health, and Child and Family Research Institute, University of British Columbia, Vancouver BC On behalf of the SOGC Hypertension Guideline Committee
REFERENCES 1. Magee LA, Pels A, Helewa M, Rey E, von Dadelszen P; SOGC Hypertension Guideline Committee. Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy: executive summary. SOGC Clinical Practice Guideline No. 307, May 2014. J Obstet Gynaecol Can 2014;36:416–38. 2. Magee LA, Pels A, Helewa M, Rey E, von Dadelszen P. Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy. Pregnancy Hypertens 2014;4:105–45. 3. Firoz T, Magee L, MacDonell K, Payne B, Gordon R, Vidler M, et al.; the Community Level Interventions for Pre-eclampsia (CLIP) Working Group. Oral antihypertensive therapy for severe hypertension in pregnancy and postpartum: a systematic review. BJOG 2014; May 16. doi: 10.1111/1471-0528.12737. [Epub ahead of print] 4. National Institute for Health and Clinical Excellence. Hypertension in Pregnancy: The management of hypertensive disorders during pregnancy. NICE Clinical Guideline 2010;107:1–295. 5. Moore MP, Redman C. The treatment of hypertension in pregnancy. Curr Med Res Opin 1982;8:39–46. J Obstet Gynaecol Can 2014;36(7):575–576
576 l JULY JOGC JUILLET 2014
In Response To the Editor: I read with interest Dr Somerset’s suggestion regarding the review process of SOGC’s clinical practice guidelines. It is timely, as we have embarked on a major overhaul of our guideline processes. We have formed an oversight committee, with wide national representation and leading experts, to review the current processes and make recommendations for improvements. The recommendations will be based on the best evidence and a survey of the practices of other leading associations. As a first step, our current guidelines have been independently reviewed and the results presented at the recent Cochrane Canada Annual Symposium 2014, 20/20 Vision: Cochrane in the Next Decade. One of the areas we will be looking at is peer review and consultation with both users and the interested public. It is our hope to maintain the quality of our guidelines, improve their utility, and maximize the benefit of the electronic era. We will also look to collaborate with other groups that are developing guidelines: more documents on the same subjects are not always better! Dr Somerset’s comments will be forwarded to the Guideline Oversight and Management Committee. Jennifer Blake, MD, MSc FRCSC Chief Executive Officer, The Society of Obstetricians and Gynaecologists of Canada, Ottawa ON J Obstet Gynaecol Can 2014;36(7):576
Use of the Papanicolaou Test in Women Under 25 Years of Age in Southern Alberta To the Editor: Rayven Snodgrass et al.1 report that cervical cancer continues to be screened by Pap smear in women under 25, regardless of recommendations to the contrary. The authors conclude that Pap smear is not useful in that population and that it sometimes leads to overtreatment. However, that conclusion must be nuanced. Indeed, even though mass screening before the age of 25 results in few positive cases and thus is not cost-effective on an epidemiological level, we must nevertheless keep in mind that in the majority of cases, cervical cancer is an STI, which therefore targets sexually active women.
Diagnosis, Evaluation, and Management of the Hypertensive Disorders of Pregnancy: Executive Summary To the Editor: In this comprehensive new SOGC Guideline1 I was surprised to see that methyldopa and (to some extent) clonidine are recommended as “alternative” oral therapeutic agents for the treatment of severe hypertension. While the immediaterelease nifedipine capsule has an onset of action approximately 20 minutes after administration and oral labetalol 20 minutes to two hours (peak effect 1 to 4 hours), the onset of action of oral methyldopa is four to six hours and immediate-release clonidine 30 minutes to one hour (peak effect 2 to 4 hours).2 While this is the executive summary (23 pages!) and it does not contain discussion on treatment, it is widely recognized that severe hypertension (defined in this guideline as a systolic blood pressure > 160 mmHg or a diastolic pressure > 110 mmHg) is associated with an increased risk of severe morbidity and mortality and should be controlled rapidly. Given this, I question the wisdom of “recommending” treatment that may take up to six hours to have a clinical effect. I trust that the diagnostic criteria for severe hypertension will be more fully discussed in the main document, since at least one well-quoted case series reports four of 24 peripartum strokes occurring with maternal systolic blood pressures of between 155 and 160 mmHg.3 Finally, I would like to suggest that in this electronic age future SOGC guidelines be circulated to the membership in draft form, so that all interested parties have a chance to review and comment before formal publication. David Somerset, FRCSC, FRCOG, FRANZCOG Departments of Obstetrics & Gynaecology and Radiology, University of Calgary, Calgary AB
REFERENCES 1. Magee LA, Pels A, Helewa M, Rey E, von Dadelszen P; SOGC Hypertension Guideline Committee. Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy: executive summary. SOGC Clinical Practice Guideline No. 307, May 2014. J Obstet Gynaecol Can 2014;36(5):416–38. 2. Drug Information (Lexicomp). UpToDate. Waltham, MA. Available at: http://www.uptodate.com/home/drugs-drug-interaction. Accessed May 6, 2014.
3. Martin JN Jr, Thigpen BD, Moore RC, Rose CH, Cushman J, May W. Stroke and severe preeclampsia and eclampsia: a paradigm shift focusing on systolic blood pressure. Obstet Gynecol 2005;105(2):246. J Obstet Gynaecol Can 2014;36(7):575
In Response To the Editor: We thank Dr Somerset for his comments. To clarify, the new Canadian guidelines have been published in two documents: an executive summary published in JOGC1 and a full-text, open-access version in Pregnancy Hypertension.2 The latter contains everything that is in the JOGC version, plus additional text and references for all sections. This arrangement was struck to balance the needs of the SOGC membership and the space constraints of the Journal. The link to the open access Pregnancy Hypertension document can be made by clicking on the link within the abstract of the document in JOGC. We also thank Dr Somerset for highlighting the critical issue of treatment of severe hypertension (≥ 160 mmHg systolic and/or ≥ 110 mmHg diastolic). This is discussed in detail beginning on page 119 of the Pregnancy Hypertension document.2 Strong recommendations (grade 1-A) are made for the use of parenteral labetalol, parenteral hydralazine, and oral nifedipine capsules for severe hypertension. Oral methyldopa and oral clonidine are suggested as alternatives, and were given lower ratings for quality of evidence and strength of recommendation (I-B and III-B, respectively). First, inclusion of oral agents for treatment of severe hypertension in the recommendations is aimed at getting severe hypertension treated, and treated more quickly in women cared for outside well-resourced facilities, be they rural health units or doctor’s offices where parenteral therapy and monitoring are not possible and transfer to hospital can take a few hours.3 Second, Dr Somerset raises the issue of how quickly severe hypertension must be treated. Most cases are without symptoms and present as part of a “hypertensive urgency”2; therefore, the severe hypertension can be managed over hours rather than minutes. Finally, we agree with Dr Somerset’s pharmacokinetic parameters for oral agents, and would add that the effect of oral nifedipine capsules peaks at one to four hours. The 2010 NICE guidelines from the United Kingdom list oral labetalol (200 mg) as one of the agents of first choice for severe hypertension in pregnancy.4 In the only relevant randomized controlled trial, oral methyldopa (250 mg) and labetalol (100 mg) JULY JOGC JUILLET 2014 l 575
LetterS to the Editor
were each effective in approximately 50% of women with severe hypertension, compared with > 80% effectiveness using nifedipine in other trials.5 Our perspective is that this therapeutic strategy is a reasonable alternative to providing nothing at all. We are conducting an ongoing trial of oral methyldopa versus nifedipine capsules versus labetalol that should help to clarify this issue. We cannot comment on the official SOGC policy on peer review. However, what we can say is that from January 2013 to January 2014, our Canadian Hypertensive Disorders of Pregnancy Working Group responded to three full rounds of peer review from the Hypertension Guideline Committee, the Maternal Fetal Medicine and Family Physician Advisory Committees, and the Executive and Council of the SOGC. Of course, we are more than happy to respond to questions and/or concerns from the membership as we move forward together in practice and in research. Laura A. Magee, MD, FRCPC Departments of Medicine and Obstetrics and Gynaecology, School of Population and Public Health, and Child and Family Research Institute, University of British Columbia, Vancouver BC Anouk Pels, MSc Amsterdam, The Netherlands Michael Helewa, MD, FRCSC Department of Obstetrics, Gynecology and Reproductive Sciences, University of Manitoba, Winnipeg MB Evelyne Rey, MD, MSc Department of Obstetrics and Gynaecology and Research Centre, CHU Sainte-Justine, University of Montreal, Montreal QC Peter von Dadelszen, MB ChB, DPhil, FRCSC Department of Obstetrics and Gynaecology, School of Population and Public Health, and Child and Family Research Institute, University of British Columbia, Vancouver BC On behalf of the SOGC Hypertension Guideline Committee
REFERENCES 1. Magee LA, Pels A, Helewa M, Rey E, von Dadelszen P; SOGC Hypertension Guideline Committee. Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy: executive summary. SOGC Clinical Practice Guideline No. 307, May 2014. J Obstet Gynaecol Can 2014;36:416–38. 2. Magee LA, Pels A, Helewa M, Rey E, von Dadelszen P. Diagnosis, evaluation, and management of the hypertensive disorders of pregnancy. Pregnancy Hypertens 2014;4:105–45. 3. Firoz T, Magee L, MacDonell K, Payne B, Gordon R, Vidler M, et al.; the Community Level Interventions for Pre-eclampsia (CLIP) Working Group. Oral antihypertensive therapy for severe hypertension in pregnancy and postpartum: a systematic review. BJOG 2014; May 16. doi: 10.1111/1471-0528.12737. [Epub ahead of print] 4. National Institute for Health and Clinical Excellence. Hypertension in Pregnancy: The management of hypertensive disorders during pregnancy. NICE Clinical Guideline 2010;107:1–295. 5. Moore MP, Redman C. The treatment of hypertension in pregnancy. Curr Med Res Opin 1982;8:39–46. J Obstet Gynaecol Can 2014;36(7):575–576
576 l JULY JOGC JUILLET 2014
In Response To the Editor: I read with interest Dr Somerset’s suggestion regarding the review process of SOGC’s clinical practice guidelines. It is timely, as we have embarked on a major overhaul of our guideline processes. We have formed an oversight committee, with wide national representation and leading experts, to review the current processes and make recommendations for improvements. The recommendations will be based on the best evidence and a survey of the practices of other leading associations. As a first step, our current guidelines have been independently reviewed and the results presented at the recent Cochrane Canada Annual Symposium 2014, 20/20 Vision: Cochrane in the Next Decade. One of the areas we will be looking at is peer review and consultation with both users and the interested public. It is our hope to maintain the quality of our guidelines, improve their utility, and maximize the benefit of the electronic era. We will also look to collaborate with other groups that are developing guidelines: more documents on the same subjects are not always better! Dr Somerset’s comments will be forwarded to the Guideline Oversight and Management Committee. Jennifer Blake, MD, MSc FRCSC Chief Executive Officer, The Society of Obstetricians and Gynaecologists of Canada, Ottawa ON J Obstet Gynaecol Can 2014;36(7):576
Use of the Papanicolaou Test in Women Under 25 Years of Age in Southern Alberta To the Editor: Rayven Snodgrass et al.1 report that cervical cancer continues to be screened by Pap smear in women under 25, regardless of recommendations to the contrary. The authors conclude that Pap smear is not useful in that population and that it sometimes leads to overtreatment. However, that conclusion must be nuanced. Indeed, even though mass screening before the age of 25 results in few positive cases and thus is not cost-effective on an epidemiological level, we must nevertheless keep in mind that in the majority of cases, cervical cancer is an STI, which therefore targets sexually active women.
