Posture-related changes in sympathetic baroreflex sensitivity during normal pregnancy.
Clin Auton Res
; 32(6): 485-495, 2022 12.
Article
en En
| MEDLINE
| ID: mdl-36394777
ABSTRACT
Normal pregnancy is associated with vast adjustments in cardiovascular autonomic control. Sympathetic baroreflex sensitivity has been reported to be attenuated during pregnancy in animal models, but most studies in humans are cross-sectional and findings from longitudinal case studies are inconclusive. It remains unclear how sympathetic baroreflex sensitivity is altered longitudinally during pregnancy within an individual in different body postures. Therefore, this study examined the impact of posture on sympathetic baroreflex sensitivity in 24 normal-weight normotensive pregnant women. Spontaneous sympathetic baroreflex sensitivity was assessed during early (6-11 weeks) and late (32-36 weeks) pregnancy and 6-10 weeks postpartum in the supine posture and graded head-up tilt (30° and 60°). In addition, data from the postpartum period were compared with (and no different to) 18 age-matched non-pregnant women to confirm that the postpartum period was reflective of a non-pregnant condition (online supplement). When compared with postpartum (-3.8 ± 0.4 bursts/100 heartbeats/mmHg), supine sympathetic baroreflex sensitivity was augmented during early pregnancy (-5.9 ± 0.4 bursts/100 heartbeats/mmHg, P < 0.001). However, sympathetic baroreflex sensitivity at 30° or 60° head-up tilt was not different between any phase of gestation (P > 0.05). When compared to supine, sympathetic baroreflex sensitivity at 60° head-up tilt was significantly blunted during early (Δ2.0 ± 0.7 bursts/100 heartbeats/mmHg, P = 0.024) and late (Δ1.5 ± 0.6 bursts/100 heartbeats/mmHg, P = 0.049) pregnancy but did not change postpartum (Δ0.4 ± 0.6 bursts/100 heartbeats/mmHg, P = 1.0). These data show that time-course changes in sympathetic baroreflex sensitivity are dependent on the posture it is examined in and provides a foundation of normal blood pressure regulation during pregnancy for future studies in women at risk for adverse pregnancy outcomes.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Postura
/
Barorreflejo
Tipo de estudio:
Diagnostic_studies
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Observational_studies
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Prevalence_studies
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Prognostic_studies
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Risk_factors_studies
Límite:
Animals
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Female
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Humans
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Pregnancy
Idioma:
En
Revista:
Clin Auton Res
Asunto de la revista:
NEUROLOGIA
Año:
2022
Tipo del documento:
Article
País de afiliación:
Estados Unidos