Table 1: Prevalence of cardiac autonomic neuropathy in different studies.

ReferenceYearN of subjectsType of DMPopulationDiagnosis tests for CANCriteria appliedCAN prevalence (%)

O’Brien [44]1991506Type 1Mean age 45 years, mean DM duration 15 yearsHRV: rest, deep breathing, Valsalva, lying to standing2 or more test positive17

Ziegler [59]1992647
Type 1HRV: coefficient of variations, spectral analysis, Valsalva, lying to standing3 or more test positive25.3
524Type 234.3

Kennedy [60]1995290Type 1Potential recipients of a pancreas transplantDeep breathingSingle test positive90

Kempler [12]20023007Type 1Mean age 32 years, mean DM duration 14 yearsHR lying to standing, postural BPSingle test positive36

Gaede [2]2003160Type 2Mean age 55 years, HbA1c 8.8% at baselineDeep breathing, postural BPSingle test positive27.5

Low [61]200483Type 1Sudomotor axon-reflex test, Valsalva, BP and HR response to standing, deep breathing2 or more test positive54
148Type 273

Pop-Busui [5]2010620Type 1—intensive treatment groupMean age 47 years, mean DM duration 26 yearsDeep breathing, Valsalva, postural BP2 or more test positive29
591Type 1—conventional treatment group35

DM: diabetes mellitus; CAN: cardiac autonomic neuropathy; HRV: heart rate variability; BP: blood pressure; HR: heart rate.