Impaired short-term blood pressure regulation and autonomic dysbalance in children with type 1 diabetes mellitus

Abstract

Aims Because reduction in baroreceptor sensitivity (BRS) has been associated with hypertension in the normal population and with increased cardiovascular morbidity and mortality in patients with diabetes mellitus, we measured BRS in a patient cohort of children with type 1 diabetes mellitus. Methods Two hundred and eight children (150 patients with type 1 diabetes mellitus, mean age 13.9±2.8 years, 70 boys, mean HbA 1c 7.8±1.4%; and 58 healthy controls, mean age 14.1±3.1 years, 32 boys) were studied. BRS and heart rate variability (HRV) were analysed from a shorttime ECG and BP recording using the sequence method (BRS) and the frequency domain method (HRV). Results There were 111 of 150 patients (74%) and 5 of 58 controls (8.6%) that showed impaired BRS. Mean BRS differed significantly between patients and controls (18.4± 7.2 vs 25.8 ± 8.2 ms/mm, p < 0.001). BRS correlated inversely with systolic BP (r=−0.23, p=0.009) and was related to diabetes duration (r=−0.194, p=0.027). Analysis of HRV showed greater sympathetic and less parasympathetic influence in patients than in controls (low frequency/ high frequency ratio 1.3±0.8 vs 0.9±0.6, p<0.05); the low frequency/high frequency ratio was inversely correlated with BRS (r=−0.28, p=0.001). Conclusions/interpretation Diabetic children show reduced BRS. In our patient group, the single risk factor for this finding was found to be the disease duration. The degree of BRS impairment was related to the degree of autonomic dysbalance.

Baroreceptor sensitivity and diabetes mellitus

“…Improved glycemic control slows the progression of DM [84] and should therefore improve prognosis in such patients. BRS has also been correlated with HbA1c level [82].…”

“…Female diabetic patients have been shown to have lower BRS and worse prognosis than their male counterparts [81]. Also, there exists a negative correlation between the disease duration and the BRS in diabetic patients [82]. Studies in DM patients have demonstrated that the degree of autonomic (sympathovagal) imbalance determines the extent of BRS impairment [82].…”

“…Also, there exists a negative correlation between the disease duration and the BRS in diabetic patients [82]. Studies in DM patients have demonstrated that the degree of autonomic (sympathovagal) imbalance determines the extent of BRS impairment [82]. In addition, the extent of BRS impairment is also a determinant factor as a more depressed BRS has been associated with a poorer prognosis [81,83].…”

Cardiovascular Autonomic Nervous System Function and Aerobic Capacity in Type 1 Diabetes

“…Also the relation between exercise and decreased sympathetic activity has been suggested (Billman, 2002). Impaired cardiovascular ANS function has been associated with type 1 diabetes (T1D) (Ziegler et al, 2001; Riihimaa et al, 2002; Dalla Pozza et al, 2007; Lucini et al, 2009; Rosengård-Bärlund et al, 2009; Spallone et al, 2011; Kuehl and Stevens, 2012). Recently, we reported lower aerobic capacity (VO 2peak ) in Type 1 diabetes patients than in healthy controls (Peltonen et al, 2012), which is in agreement with several other papers (Niranjan et al, 1997; Komatsu et al, 2005; Gusso et al, 2008; Nadeau et al, 2010).…”

Increased peripherin in sympathetic axons innervating plantar metatarsal arteries in STZ-induced type I diabetic rats

“…While there appears to be no direct investigations of perivascular sympathetic nerves in human diabetics, there are reports of increased, rather than decreased, sympathetic vasomotor regulation in young type 1 diabetics (e.g., Dalla Pozza et al, 2007; Lucini et al, 2009). In addition, a number of studies have reported that reductions in parasympathetic control of the heart in type 1 diabetic patients precede impairment of sympathetic vasomotor regulation (e.g., Javorka et al, 2005; Dalla Pozza et al, 2007). These findings suggest vasoconstrictor sympathetic neurons are less vulnerable to the neurotoxic effects of Type 1 diabetes.…”