Cardiometabolic correlates of sleep‐disordered breathing in renal transplant children

Abstract

Sleep‐disordered breathing, a prevalent condition among adult renal transplant (RTx) recipients, has become an established independent risk factor of MetS, and furthermore, it might contribute to increased CV risk. Despite the proven correlations in adults, there is a lack of evidence for its significance in the pediatric RTx population. In this study, we aimed at assessing the prevalence and the clinical correlates of SDB in RTx children. Data of 13 patients (age [mean ± SD]: 14.2 ± 2.7 years) were analyzed. SDB was evaluated by PSG, as severity score OAHI was applied. Carbohydrate metabolism was characterized by OGTT, whereas CV status was studied by ABPM. Three composite end‐points were calculated as sum of z‐scores: daytime systolic and diastolic BP; nighttime systolic and diastolic BP; and glucose and insulin levels at 120 minutes. Eight patients (61.5%) were diagnosed with SDB of whom five patients (38.5%) had moderate or severe SDB. In linear regression analysis, OAHI during REM was associated with the CV variables (daytime BP P = 0.032, ß = 0.748; nighttime BP P = 0.041, ß = 0.715), and the correlations remained significant after adjustments for BMI. However, we did not confirm a significant association with the metabolic variables. The prevalence of SDB was high, and its severity during REM was a predictor of the BP suggesting that RTx children with SDB might be at risk of developing CV complications, especially HTN similarly to adults.

Hypertension in pediatric kidney transplantation

“…Sleep‐disordered breathing including sleep apnea syndrome (SAS) may be present in transplanted children and the indices of SAS correlate with nighttime BP. This suggests that transplanted children with SAS might be at risk of developing hypertension, similar to adults with SAS posttransplant 47 …”

“…In adults, impaired graft function is associated with elevated BP and increased risk of HTN. 12 In a single-center pediatric study, Mitsnefes et al 44 47 Low birth weight, a prenatal factor contributing to hypertension, has been shown to be a risk factor for hypertension not only in general population but also for transplanted children. 48 Unfortunately, it remains an unmodifiable risk factor of HTN in both the general population and posttransplant patients.…”

Sleep Apnea and the Kidney

“…In transplanted children, 61% of the sample showed evidence of OSA that was moderate-severe in 38.5% and associated with uncontrolled hypertension. However, SDB was likely to be overestimated, since prevalence of obesity and metabolic abnormalities tended to be higher in children undergoing PSG compared to children refusing participation to the study [67].…”