BACKGROUND: Increased heart rate (HR) and diminished heart rate variability (HRV) are signs of early cardiovascular autonomic neuropathy. We tested the hypotheses that increased HR and diminished HRV are present in people: (i) with increased fasting glucose (FG) levels not in the range of diabetes mellitus (DM), and (ii) in people with the metabolic syndrome (MetS) independent of elevated FG levels. METHODS: HR and HRV were determined in 1267 adults (mean age 72 years) who had Holter monitoring and FG measures: 536 had normal FG levels (NORM, FG 4.5-5.5 mmol/l), 363 had mildly impaired FG (IFG-1, FG 5.6-6.0 mmol/l), 182 had significantly impaired FG (IFG-2, FG 6.1-6.9 mmol/l) and 178 had DM (FG > 6.9 mmol/l or use of glucose-lowering agents/insulin). HR and HRV in NORM/IFG-1 was further compared by the number of components of the MetS and compared by the presence or absence of MetS in IFG-2/DM. RESULTS: HRV indices were more impaired in IFG-2 and DM than in NORM or IFG-1. There were few differences in HRV indices between NORM and IFG-1 or between IFG-2 and DM. In NORM/IFG-1 participants, having > or = 2 components of the MetS was associated with a greater decrease in HRV compared with having no or one components. In IFG-2/DM participants, MetS was associated with decreased HRV compared with no MetS. CONCLUSIONS: Increased HR and diminished HRV occur in the non-diabetic FG range. Diminished HRV is associated with the MetS, independent of FG levels. Both these results suggest that factors associated with increasing non-diabetic FG levels and the MetS play a role in the onset of cardiac autonomic impairment.
BACKGROUND: Increased heart rate (HR) and diminished heart rate variability (HRV) are signs of early cardiovascular autonomic neuropathy. We tested the hypotheses that increased HR and diminished HRV are present in people: (i) with increased fasting glucose (FG) levels not in the range of diabetes mellitus (DM), and (ii) in people with the metabolic syndrome (MetS) independent of elevated FG levels. METHODS: HR and HRV were determined in 1267 adults (mean age 72 years) who had Holter monitoring and FG measures: 536 had normal FG levels (NORM, FG 4.5-5.5 mmol/l), 363 had mildly impaired FG (IFG-1, FG 5.6-6.0 mmol/l), 182 had significantly impaired FG (IFG-2, FG 6.1-6.9 mmol/l) and 178 had DM (FG > 6.9 mmol/l or use of glucose-lowering agents/insulin). HR and HRV in NORM/IFG-1 was further compared by the number of components of the MetS and compared by the presence or absence of MetS in IFG-2/DM. RESULTS: HRV indices were more impaired in IFG-2 and DM than in NORM or IFG-1. There were few differences in HRV indices between NORM and IFG-1 or between IFG-2 and DM. In NORM/IFG-1 participants, having > or = 2 components of the MetS was associated with a greater decrease in HRV compared with having no or one components. In IFG-2/DMparticipants, MetS was associated with decreased HRV compared with no MetS. CONCLUSIONS: Increased HR and diminished HRV occur in the non-diabetic FG range. Diminished HRV is associated with the MetS, independent of FG levels. Both these results suggest that factors associated with increasing non-diabetic FG levels and the MetS play a role in the onset of cardiac autonomic impairment.
Authors: Daniel J Pelchovitz; Jason Ng; Alexandru B Chicos; Daniel W Bergner; Jeffrey J Goldberger Journal: Am J Physiol Heart Circ Physiol Date: 2012-04-27 Impact factor: 4.733
Authors: Dan Ziegler; Andreas Voss; Wolfgang Rathmann; Alexander Strom; Siegfried Perz; Michael Roden; Annette Peters; Christa Meisinger Journal: Diabetologia Date: 2015-02-28 Impact factor: 10.122
Authors: Shivam Champaneri; Gary S Wand; Saurabh S Malhotra; Sarah S Casagrande; Sherita Hill Golden Journal: Curr Diab Rep Date: 2010-12 Impact factor: 4.810