Clinical trial NCT02948439: Prenatal Exercise and Cardiovascular Health (PEACH)
Official title: Exercise and Neurovascular Function During Pregnancy
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Pregnancy
Keywords: pregnancy
cardiovascular
nervous system
exercise
Lead sponsor: University of Alberta
Sponsor class: OTHER
First posted: 2016-10-28
Enrollment: 64
Sex: FEMALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Maintenance of a healthy pregnancy depends on an appropriate adaptation and responsiveness of blood vessels, to ensure appropriate blood flow to the fetus during everyday stressors. Previous work by the investigators has demonstrated that during pregnancy, the part of the nervous system responsible for cardiovascular function (the sympathetic nervous system) is hyperactive. The investigators also know that in women who develop high blood pressure during pregnancy that sympathetic nervous system activity is even higher. Yet, very little is known about why this occurs and how this might be affected.

Pregnant women are encouraged to be active, yet, less than 15% of women perform sufficient exercise to meet current guidelines. This is important because hyperactivity of the sympathetic nervous system is observed in other inactive populations and has been linked to adverse cardiovascular health outcomes including hypertension, atherosclerosis, heart attack, and stroke. Indeed, in 2011, the American Heart Association stated that inactivity was a risk factor as potent as cigarette smoking for the development of future cardiovascular disease in women.

The investigators' work and others have demonstrated that exercise during pregnancy is beneficial for both the mom and baby; however, the effect of prenatal exercise on neurovascular function is not known. If exercise is effective in controlling the increase in sympathetic activity that occurs during pregnancy, or its effects on the cardiovascular system, this may help prevent the development of high blood pressure or other cardiovascular problems during pregnancy.

Detailed description: The objectives of this study are to: 1) examine the impact of exercise on sympathetic and vascular function during pregnancy; 2) examine the role of endothelial function on the vascular effects of exercise during pregnancy.

Study design:

100 women (\>18yrs) will be recruited in the first or second trimester (\<20 wks). Women with multiple pregnancies will be excluded. Eligible women will be randomized between an aerobic exercise intervention (EXER) or no intervention (CTRL).

Initial testing will take place between 16-20 weeks of pregnancy. Following initial baseline testing, women will be randomly assigned to an exercise intervention or no intervention. Women will receive an opaque sequentially numbered envelop with their allocation. Allocation will be determined using a randomly generated allocation sequence by an individual not associated with the research study. The intervention will consist of aerobic exercise equivalent to 50-70% of heart rate reserve, 3-4 times per week until the end of the study (34-36 weeks). For initial baseline testing (16-20 weeks) and at the end of the intervention (34-36 weeks), participants will visit the laboratory twice

On Day 1, participants will complete a peak exercise test on the treadmill or bike to volitional fatigue to measures fitness and cardiovascular/cerebrovascular responses to exercise.

On Day 2 Participants will arrive fasted (12 hrs) and blood samples will be collected. Anthropometrics, personal/familial history of hypertension and pregnancy complications will be recorded. Following a standardized breakfast, participants will undergo an assessment of reflex neurovascular control including a cold pressor test, flow mediated dilation and end expiratory voluntary breath hold. Muscle sympathetic nerve activity, ultrasound (blood flow and diameter of brachial, femoral and carotid arteries), blood pressure, heart rate and respiratory variables will be measured.

OUTCOME/IMPACT

Pregnancy is a stress-test for life; with women who develop complications during pregnancy having a higher risk for cardiovascular disease later in life. Exercise is well known to prevent cardiovascular disease through improvements in endothelial function and the sympathetic nervous system. Whether this improvements is also seen in pregnancy remains to be seen.

Eligibility criteria: Inclusion Criteria:

* \>18 years old
* singleton pregnancy
* cleared to exercise by health care provider using Par Med X for Pregnancy (CSEP)

Exclusion Criteria:

* multiple gestation
* absolute contraindication to exercise (CSEP)
* \<18 years old
* develops any contraindication during intervention

Primary outcomes:
measure: Sympathetic Nerve Activity - cold pressor test response
timeFrame: 16-20 weeks and 34-36 weeks gestation
Secondary outcomes:
measure: Respiratory measures - respiratory frequency
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Sympathetic Nerve Activity - breath hold response
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Respiratory measures - tidal volume
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Respiratory measures - oxygen
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Respiratory measures - carbon dioxide
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Respiratory measures - lung volume
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Cerebral blood flow at rest
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Cerebral autoregulation
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Cerebral blood flow during exercise
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: fasted blood sample - blood volume
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: fasted blood sample - neurotransmitters
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: fasted blood sample- inflammatory markers
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: fasted blood sample- epigenetics
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: fasted blood sample- sex hormones
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: fasted blood sample- metabolic
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: fetal outcomes- birth weight
timeFrame: within one month postpartum
measure: fetal outcomes- length
timeFrame: within one month postpartum
measure: fetal outcomes- gestational age
timeFrame: within one month postpartum
measure: maternal outcomes- mode of delivery
timeFrame: within one month postpartum
measure: maternal outcomes- delivery complications
timeFrame: within one month postpartum
measure: maternal outcomes- pregnancy complications
timeFrame: any time during study
measure: fetal outcomes- apgar score
timeFrame: within one month postpartum
measure: fetal outcomes- NICU
timeFrame: within one month postpartum
measure: maternal outcomes- gestational weight gain
timeFrame: within one month postpartum
measure: Endothelial Function - time to peak dilation
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Endothelial Function- flow mediated dilation
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Endothelial Function - shear stress
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Accelerometry
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Physical Activity Questionnaire
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Depression rating
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Sleep Quality
timeFrame: 16-20 weeks and 34-36 weeks gestation
measure: Food log
timeFrame: 16-20 weeks and 34-36 weeks gestation
Other outcomes:
Locations:
city: Edmonton
country: Canada
facility: Program for Pregnancy and Postpartum Health, University of Alberta
state: Alberta
Study officials:
affiliation: University of Alberta
name: Rachel Skow, MSc
role: STUDY_DIRECTOR
References:
citation: Boparai R, Skow RJ, Farooq S, Steinback CD, Davenport MH. Prenatal exercise and cardiovascular health (PEACH) study: the remote effect of aerobic exercise training on conduit artery and resistance vessel function. Appl Physiol Nutr Metab. 2021 Dec;46(12):1459-1468. doi: 10.1139/apnm-2020-0902. Epub 2021 Jun 23.
citation: Skow RJ, Fraser GM, Steinback CD, Davenport MH. Prenatal Exercise and Cardiovascular Health (PEACH) Study: Impact on Muscle Sympathetic Nerve (Re)Activity. Med Sci Sports Exerc. 2021 Jun 1;53(6):1101-1113. doi: 10.1249/MSS.0000000000002583.