Lower Haptoglobin Linked to Nocturnal BP Non-Dipping in Children With CKD, finds study
Researchers have found in a new study that lower circulating haptoglobin levels were independently associated with nocturnal blood pressure non-dipping in children with chronic kidney disease. The findings suggest that reduced hemoglobin-binding and buffering capacity may play a role in disrupted circadian BP regulation, although further mechanistic studies are needed to confirm causality. The study was published in the journal BMC Nephrology by Pei-Chen Lu and colleagues.
In order to assess the relationship between the level of haptoglobin in plasma and the circadian pattern of blood pressure, 60 children suffering from chronic kidney disease were selected to take part in the study. The concentration of haptoglobin in plasma was accurately measured by applying an enzyme-linked immunosorbent assay (ELISA) technique.
Out of these 60 individuals, 25 underwent 24 hours ABPM to measure their nighttime systolic blood pressure dipping. Non-dipping during nighttime was regarded as the condition wherein no reduction in the nighttime level of blood pressure of 10% or more than that occurs compared to the daytime.
Key findings:
- Among the 25 children who completed 24-hour ABPM, 15 participants (60%) exhibited nocturnal systolic blood pressure non-dipping (<10% nighttime decline).
- Circulating plasma haptoglobin levels were significantly lower in nocturnal non-dippers compared to normal dippers.
- Each 10 mg/dL increase in plasma haptoglobin was independently associated with 26% lower odds of nocturnal non-dipping (adjusted OR 0.74, 95% CI 0.49–0.99; p = 0.044) after adjusting for age and sex.
- Restricted cubic spline modeling demonstrated a threshold-like increase in non-dipping risk at lower plasma haptoglobin concentrations.
In summary, decreased serum concentrations of haptoglobin are independently associated with non-dipping nocturnal BP in children suffering from chronic kidney disease. The observed 26% decreased risk of non-dipping for each 10 mg/dL increment of haptoglobin level suggests that the function of the hemoglobin buffer is possibly significant for maintaining vascular tone in the circadian rhythm. Further studies need to be conducted in order to elucidate this mechanism and determine whether there exists any possibility for treatment of this disorder.
Reference:
Lu, PC., Liao, WT., Hsu, CN. et al. Haptoglobin is associated with nocturnal blood pressure non-dipping in children with chronic kidney disease. BMC Nephrol (2026). https://doi.org/10.1186/s12882-026-05295-0
