Adenotonsillectomy lowers high blood pressure in children with OSA

Obstructive sleep apnea (OSA) is a spectrum of disorders ranging from simple snoring to complete obstruction of upper airways during sleep, which affects both children and adults.

The most common cause of obstructive sleep apnea in children is chronic adenotonsillar hypertrophy, and so adenotonsillectomy is considered as the first-line treatment for OSA in children.

Obstructive Sleep Apnea and Hypertension

Hypertensive and cardiovascular complications of OSA in adults is well known. In adults, intermittent hypoxia and hypercapnia due to OSA promote nocturnal hypertension, leading to the development of sustained daytime hypertension through sympathetic activation, inflammation, oxidative stress, and endothelial dysfunction. This eventually leads to sequential cardiovascular morbidities.

High blood pressure (BP) in children with OSA was first described by Gillenminault et al in 1976. Since then, various studies have been done on this domain, and as usual, there exist controversies in the literature regarding blood pressure changes after adenotonsillectomy in children with OSA.

A meta-analysis in 2007 reported that associated evidence between moderate to severe childhood OSA and hypertension is insufficient. Similarly, the Childhood Adenotonsillectomy Trial and study by Apostolidou et al observed that no significant change in cardiometabolic measures happens in children with OSA after surgery.

But several subsequent studies after the meta-analysis reported that children with moderate to severe OSA are having higher pre-op BP than controls. Studies by Amin et al, Ng et al, Kang et al, and Li et al found that diastolic BP reduces in children after surgery.

In a study conducted at Cincinnati Children’s Hospital Medical Center headed by Lisa Burns, MD, (Pulmonary Fellow at Cincinnati Children’s Hospital Medical Center), they observed that in some children with OSA, adenotonsillectomy lowers high blood pressure significantly within 24 months of the procedure. In addition, in a subset of children with moderate to severe sleep apnea, there was a decrease in heart size after adenotonsillectomy.

“Our study emphasizes the importance of treating severe sleep apnea in order to prevent persistent elevation in blood pressure and end-organ damage. We also shown that diastolic blood pressure, is more sensitive to the effects of sleep apnea than other measures of blood pressure. – Dr. Burns said. “

Problems with pediatric hypertension

Hypertension in childhood may continue into adulthood and be associated with adverse cardiovascular outcomes.

In the Young Finns study, it was observed that childhood hypertension is associated with increased arterial stiffness in adulthood associated with adverse cardiovascular outcomes.

Juonala et al observed that carotid artery intima and media thickness which is a predictor for atherosclerosis is found to be increased in children with elevated BP. This can eventually lead to early adult cardiovascular disease.

Adenotonsillectomy can lower the blood pressure.

In a recent article published in JAMA Otolaryngology, Cho-Hsueh Lee et al from Taiwan studied the effect of adenotonsillectomy among 582 children with obstructive sleep apnea. The study was conducted during the period of January 1, 2010, to April 30, 2016.

All the children with suspected OSA underwent polysomnography (PSG). An apnea-hypopnea-index (AHI) of 1 and above was considered as diagnostic for pediatric OSA. These children later underwent adenotonsillectomy along with multiple pre- and post-procedural BP monitoring.

After excluding children who were not satisfying the inclusion criteria, or who belongs to exclusion criteria, they analyzed results of 240 non-obese children with OSA and a mean age of 7.3 years (66.7% boys).

From the study, authors found that postoperatively all children with OSA had significant improvement in AHI scores, Mean oxygen saturation, reduction in systolic and diastolic blood pressure values.

Those children who were previously diagnosed to have hypertension (before adenotonsillectomy) had a significant decrease in all BP measurements, including systolic BP index (nocturnal, −4.3; morning, −5.7) and diastolic BP index (nocturnal, −10.7; morning, −11.6). In contrast, children without hypertension had a slight increase in nocturnal systolic BP (103.8 to 105.9 mm Hg).

A generalized estimating equation model for subgroup comparisons found that children with hypertension had greater improvement in all BP measures than children without hypertension.

Conclusions

Hypertension in childhood may continue into adulthood and be associated with early and adverse cardiovascular outcomes. Hence early screening and appropriate treatment of hypertension in the pediatric population is important.

Children with OSA need to be screened to determine their hypertensive status and appropriate treatment should be initiated to ease their OSA symptoms and to potentially prevent future adverse cardiovascular outcomes.

References

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