Autonomic Neuropathy in Nondiabetic Offspring of Type 2 Diabetic Subjects Is Associated With Urinary Albumin Excretion Rate and 24-h Ambulatory Blood Pressure

Abstract

The aim of this study was to examine the impact of parental type 2 diabetes on the autonomic nervous system and to determine whether autonomic neuropathy is present and associated with changes in 24-h ambulatory blood pressure (AMBP) and urinary albumin excretion rate (UAER) in nondiabetic subjects with parental type 2 diabetes. We examined 223 nondiabetic offspring of type 2 diabetic subjects and a control group of 258 offspring of nondiabetic subjects. The autonomic nervous system was assessed by three cardiovascular reflex tests, 24-h AMBP was measured with an oscillometric recorder (90207; Spacelabs, Redmond, WA), and UAER was determined through three overnight urine samples. The subjects with parental type 2 diabetes had significantly lower heart rate variation in all three bedside tests (P < 0.01) than subjects without parental diabetes. The prevalence of autonomic neuropathy in the nondiabetic offspring with parental type 2 diabetes (6.7%) was significantly (P < 0.01) higher compared with the control group (1.6%). Autonomic neuropathy was associated with a higher fasting insulin level (P < 0.05), higher UAER (P < 0.001), higher 24-h mean AMBP (P < 0.01), and reduced diurnal blood pressure variation (P < 0.001) after adjustment for age, sex, and BMI. In conclusion, parental type 2 diabetes was found to be associated with alterations in the autonomic nervous system in nondiabetic subjects. The presence of autonomic neuropathy in subjects with parental type 2 diabetes was associated with higher UAER, fasting insulin level, and 24-h AMBP and a reduced diurnal blood pressure variation. This study indicates that parental type 2 diabetes has an impact on the cardiac autonomic function in nondiabetic subjects. Diabetes 50:630 -636, 2001

Alterations in heart rate variability during everyday life are linked to insulin resistance. A role of dominating sympathetic over parasympathetic nerve activity?

“…The role of ANS dysregulation in the development of IR was further supported by a small subgroup analysis of seven subjects with available longitudinal data on HRV in whom LF to HF power ratio at baseline was significantly associated with change in insulin sensitivity (M value) during the following 6 years. An imbalance in the ANS could be explained by a combination of a relative increase in sympathetic activation as well as an attenuation of parasympathetic activity and could therefore be in line with previous findings that IR is associated with both a parasympathetic dysfunction as well as an enhanced sympathetic reactivity [ 25 ].…”

“…In the present study differences in HRV between T2D relatives and controls were more pronounced in long-term than the short-term assessments suggesting that other mechanisms, such as physical activity and other life-style factors also may be of importance [ 25 ]. In addition, age-adjusted total and very low frequency (VLF) power was significantly lower in T2D relatives indicating that reduced vagal activation potentially could be an early component in the development of T2D [ 26 ].…”

Decreased β-Cell Function is Associated with Cardiovascular Autonomic Neuropathy in Chinese Patients Newly Diagnosed with Type 2 Diabetes

“…Previous studies have demonstrated that CAN is found in patients with newly-diagnosed diabetes, pre-diabetes, and even the first-degree relatives of type 2 diabetic patients with normal glucose tolerance [ 17 , 18 ]. Although CAN progresses with the duration of diabetes [ 19 ], it can be reversed at the very early stage by interventions on risk factors [ 20 ], just like other nervous system diseases [ 21 ]. Hence, it is of great clinical importance to identify CAN and its characteristics in the early stage of the disease.…”

Insulin resistance is independently associated with cardiovascular autonomic neuropathy in type 2 diabetes

“…Because of the atypical and insidious symptoms at the early stages of DCAN, the majority of type 2 diabetes mellitus patients tend to neglect the symptoms and leave it untreated clinically until the DCAN reaches a serious stage, by which time DCAN shows multiple complex and severe clinical manifestations, in turn increasing morbidity and mortality associated with a high risk of cardiac arrhythmias and sudden death 3 . Although DCAN progresses with diabetes progression 26 , early intervention and modification of risk factors could delay or reverse the progression of DCAN 27 . Therefore, early and correct identification for patients with a high risk of developing DCAN is crucial to initiate, escalate or intensify treatment.…”