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Cardiac autonomic dysfunction in type 2 diabetes - effect of hyperglycemia and disease duration.

Tarvainen MP, Laitinen TP, Lipponen JA, Cornforth DJ, Jelinek HF - Front Endocrinol (Lausanne) (2014)

Bottom Line: Heart rate variability (HRV) is reduced in diabetes mellitus (DM) patients, suggesting dysfunction of cardiac autonomic regulation and an increased risk for cardiac events.Duration of diabetes was strongly associated with decrease in HRV, the most significant decrease in HRV was found within the first 5-10 years of the disease.In conclusion, elevated blood glucose levels have an unfavorable effect on cardiac autonomic function and this effect is pronounced in long-term T2DM patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Applied Physics, University of Eastern Finland , Kuopio , Finland ; Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital , Kuopio , Finland.

ABSTRACT
Heart rate variability (HRV) is reduced in diabetes mellitus (DM) patients, suggesting dysfunction of cardiac autonomic regulation and an increased risk for cardiac events. The aim of this paper was to examine the associations of blood glucose level (BGL), glycated hemoglobin (HbA1c), and duration of diabetes with cardiac autonomic regulation assessed by HRV analysis. Resting electrocardiogram (ECG), recorded over 20 min in supine position, and clinical measurements of 189 healthy controls and 93 type 2 DM (T2DM) patients were analyzed. HRV was assessed using several time-domain, frequency-domain, and non-linear methods. HRV parameters showed a clear difference between healthy controls and T2DM patients. Hyperglycemia was associated with increase in mean heart rate and decrease in HRV, indicated by negative correlations of BGL and HbA1c with mean RR interval and most of the HRV parameters. Duration of diabetes was strongly associated with decrease in HRV, the most significant decrease in HRV was found within the first 5-10 years of the disease. In conclusion, elevated blood glucose levels have an unfavorable effect on cardiac autonomic function and this effect is pronounced in long-term T2DM patients. The most significant decrease in HRV related to diabetes and thus presence of autonomic neuropathy was observed within the first 5-10 years of disease progression.

No MeSH data available.


Related in: MedlinePlus

Box plots of selected HRV associations with BGL (A), HbA1c (B), and duration of diabetes (C). On each box, the central mark is the median, the edges of the box are the 25th and 75th percentiles, and the whiskers extend to the most extreme parameter values excluding outliers. Significant differences between all the “boxes” (A,B) or between successive “boxes” (C) were tested using the Mann–Whitney U test (***p ≤ 0.001; **p ≤ 0.01; *p ≤ 0.05).
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Figure 2: Box plots of selected HRV associations with BGL (A), HbA1c (B), and duration of diabetes (C). On each box, the central mark is the median, the edges of the box are the 25th and 75th percentiles, and the whiskers extend to the most extreme parameter values excluding outliers. Significant differences between all the “boxes” (A,B) or between successive “boxes” (C) were tested using the Mann–Whitney U test (***p ≤ 0.001; **p ≤ 0.01; *p ≤ 0.05).

Mentions: The effect of glycemia on selected HRV parameters is further illustrated in Figures 2A,B. In order to observe HRV changes related to glycemia, the diabetes group was divided into four subgroups according to BGL (3–5.5, 5.6–7, 7.1–11, and >11 mmol/L) and HbA1c (4–5.6, 5.7–6.4, 6.5–7.5, and >7.5%). The number of measurements within each subgroup varied between 32 and 66, except for the lowest HbA1c subgroup, which consisted of only four measurements. The healthy subjects were divided only into the first two glycemic (3–5.5 and 5.6–7 mmol/L) subgroups. No remarkable changes were observed between the first two glycemic (control or diabetes) subgroups, i.e., when BGL is below 7 mmol/L and HbA1c below 6.4% (46 mmol/mol), but mean RR interval and HRV were decreased for the two highest glycemic subgroups for diabetic patients.


Cardiac autonomic dysfunction in type 2 diabetes - effect of hyperglycemia and disease duration.

Tarvainen MP, Laitinen TP, Lipponen JA, Cornforth DJ, Jelinek HF - Front Endocrinol (Lausanne) (2014)

Box plots of selected HRV associations with BGL (A), HbA1c (B), and duration of diabetes (C). On each box, the central mark is the median, the edges of the box are the 25th and 75th percentiles, and the whiskers extend to the most extreme parameter values excluding outliers. Significant differences between all the “boxes” (A,B) or between successive “boxes” (C) were tested using the Mann–Whitney U test (***p ≤ 0.001; **p ≤ 0.01; *p ≤ 0.05).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4126058&req=5

Figure 2: Box plots of selected HRV associations with BGL (A), HbA1c (B), and duration of diabetes (C). On each box, the central mark is the median, the edges of the box are the 25th and 75th percentiles, and the whiskers extend to the most extreme parameter values excluding outliers. Significant differences between all the “boxes” (A,B) or between successive “boxes” (C) were tested using the Mann–Whitney U test (***p ≤ 0.001; **p ≤ 0.01; *p ≤ 0.05).
Mentions: The effect of glycemia on selected HRV parameters is further illustrated in Figures 2A,B. In order to observe HRV changes related to glycemia, the diabetes group was divided into four subgroups according to BGL (3–5.5, 5.6–7, 7.1–11, and >11 mmol/L) and HbA1c (4–5.6, 5.7–6.4, 6.5–7.5, and >7.5%). The number of measurements within each subgroup varied between 32 and 66, except for the lowest HbA1c subgroup, which consisted of only four measurements. The healthy subjects were divided only into the first two glycemic (3–5.5 and 5.6–7 mmol/L) subgroups. No remarkable changes were observed between the first two glycemic (control or diabetes) subgroups, i.e., when BGL is below 7 mmol/L and HbA1c below 6.4% (46 mmol/mol), but mean RR interval and HRV were decreased for the two highest glycemic subgroups for diabetic patients.

Bottom Line: Heart rate variability (HRV) is reduced in diabetes mellitus (DM) patients, suggesting dysfunction of cardiac autonomic regulation and an increased risk for cardiac events.Duration of diabetes was strongly associated with decrease in HRV, the most significant decrease in HRV was found within the first 5-10 years of the disease.In conclusion, elevated blood glucose levels have an unfavorable effect on cardiac autonomic function and this effect is pronounced in long-term T2DM patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Applied Physics, University of Eastern Finland , Kuopio , Finland ; Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital , Kuopio , Finland.

ABSTRACT
Heart rate variability (HRV) is reduced in diabetes mellitus (DM) patients, suggesting dysfunction of cardiac autonomic regulation and an increased risk for cardiac events. The aim of this paper was to examine the associations of blood glucose level (BGL), glycated hemoglobin (HbA1c), and duration of diabetes with cardiac autonomic regulation assessed by HRV analysis. Resting electrocardiogram (ECG), recorded over 20 min in supine position, and clinical measurements of 189 healthy controls and 93 type 2 DM (T2DM) patients were analyzed. HRV was assessed using several time-domain, frequency-domain, and non-linear methods. HRV parameters showed a clear difference between healthy controls and T2DM patients. Hyperglycemia was associated with increase in mean heart rate and decrease in HRV, indicated by negative correlations of BGL and HbA1c with mean RR interval and most of the HRV parameters. Duration of diabetes was strongly associated with decrease in HRV, the most significant decrease in HRV was found within the first 5-10 years of the disease. In conclusion, elevated blood glucose levels have an unfavorable effect on cardiac autonomic function and this effect is pronounced in long-term T2DM patients. The most significant decrease in HRV related to diabetes and thus presence of autonomic neuropathy was observed within the first 5-10 years of disease progression.

No MeSH data available.


Related in: MedlinePlus