Cardiovascular autonomic neuropathy (CAN) is a major complication of type 1 diabetes (T1D). This study aimed to
evaluate cardiac autonomic nervous system (ANS) function in children with T1D and its relation to different
demographic, clinical and laboratory variable. This cross-sectional study included 60 children with T1D (mean
age = 15.1 ± 3.3 years; duration of diabetes = 7.95 ± 3.83 years). The following 8 non-invasive autonomic testing were
used for evaluation: heart rate at rest and in response to active standing (30:15 ratio), deep breathing and Valsalva
maneuver (indicating parasympathetic function); blood pressure response to standing (orthostatic hypotension or OH),
sustained handgrip and cold; and heart rate response to standing or positional orthostatic tachycardia syndrome or
POTs (indicating sympathetic function). None had clinically manifest CAN. Compared to healthy children (5%),
36.67% of children with T1D had ≥ 2 abnormal tests (i.e., CAN) (P = 0.0001) which included significantly abnormal
heart rate response to standing (POTs) (P = 0.052), active standing (30:15 ratio) (P = 0.0001) and Valsalva maneuver
(P = 0.0001), indicating parasympathetic autonomic dysfunction, and blood pressure response to cold (P = 0.01),
indicating sympathetic autonomic dysfunction. 54.55, 27.27 and 18.18% had early, definite and severe dysfunction
of ANS. All patients had sensorimotor peripheral neuropathy. The longer duration of diabetes (> 5 years), presence
of diabetic complications and worse glycemic control were significantly associated with CAN.
Conclusions: The study concluded that both parasympathetic and sympathetic autonomic dysfunctions are common in
children with T1D particularly with longer duration of diabetes and presence of microvascular complications.