Clinical and laboratory characteristics of pediatric orthostatic hypertension: a retrospective study

Abstract

Aims: Orthostatic hypertension (OHT) is an underrecognized condition in the pediatric population, characterized by an abnormal rise in blood pressure upon standing. Given its potential long-term implications, including cardiovascular remodeling and end-organ damage, early identification and management of OHT are crucial. This study aims to evaluate the clinical and laboratory characteristics of children diagnosed with OHT, providing insights into potential risk factors and associated conditions. Methods: A retrospective, cross-sectional study was conducted at Ankara Training and Research Hospital between September 2022 and August 2024. A total of 111 pediatric patients diagnosed with OHT based on an active standing test were included. Demographic data, presenting symptoms, laboratory parameters (including vitamin B12, ferritin, and vitamin D levels) were analyzed. Results: The median age of the cohort was 15.3 years (range: 6.8–17.9), with a female predominance (63%). Nearly half of the patients (46%) were overweight or obese, and 22% had a family history of hypertension. Cardiovascular symptoms were the most common (36%), followed by cerebral hypoperfusion symptoms (35%) and other symptoms, including fatigue and concentration issues (27%). A significant proportion of the patients exhibited vitamin D deficiency (41%), vitamin B12 borderline levels (45%), and iron deficiency anemia (15%). Additionally, postural orthostatic tachycardia syndrome (POTS) was present in 24% of patients, with a notable association between POTS and low body weight (p=0.037). Conclusion: The descriptive findings of this study illustrate a range of clinical and laboratory characteristics in children with OHT, hinting at potential areas for future investigation. Although associations with pubertal status, obesity, and vitamin deficiencies were observed, the study's design limits causal inference. Future research, including control groups and prospective approaches, is crucial to understand the clinical importance of these observations.

Keywords

• Orthostatic hypertension
• autonomic dysfunction
• pediatric population
• active standing test

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