Predictors of cardiac autonomic neuropathy in patients with diabetic peripheral neuropathy

The study aimed at assessment of predictors of cardiac autonomic neuropathy (CAN) among patients with established diabetic peripheral neuropathy (DPN).

This cross-sectional study included 80 patients with DPN. Detailed history taking, physical examination and laboratory investigations were done. CAN was diagnosed by cardiac autonomic reflex tests which consists of the Valsalva ratio, lying standing heart rate (30/15 ratio), R-R interval variation, postural hypotension and sustained handgrip.

The majority of patients (about 91%) had CAN. Of them, 20% had early, 61.3% had definite and 10% had severe CAN. Compared to patients without CAN, patients with CAN were older (p = 0.002), with longer diabetes duration (DD) (p < 0.001), higher waist circumference (WC) (p < 0.001) and higher LDL-c levels. DD, HbA1c, WC, HDL-c, neuron specific enolase level, ankle brachial index (ABI) and diabetic retinopathy (DR) were associated with CAN severity. Regression analysis revealed that older age, longer DD, higher WC and LDL-c levels were associated with CAN in univariate but not multivariate analysis. However, DD was the only predictor of advanced stages of CAN (definite and severe) in multivariate analysis.

The prevalence of CAN is very high among patients with DPN (91%). Old age, long DD, high WC and LDL-c level were associated with CAN. DD could be considered as a predictor of advanced stages of CAN (definite and severe).