Abstract
Increasing age is associated with a reduction in overall heart rate variability as well as changes in complexity of physiologic dynamics. The aim of this study was to verify if the alterations in autonomic modulation of heart rate caused by the aging process could be detected by Shannon entropy (SE), conditional entropy (CE) and symbolic analysis (SA). Complexity analysis was carried out in 44 healthy subjects divided into two groups: old (n = 23, 63 ± 3 years) and young group (n = 21, 23 ± 2). It was analyzed SE, CE [complexity index (CI) and normalized CI (NCI)] and SA (0V, 1V, 2LV and 2ULV patterns) during short heart period series (200 cardiac beats) derived from ECG recordings during 15 min of rest in a supine position. The sequences characterized by three heart periods with no significant variations (0V), and that with two significant unlike variations (2ULV) reflect changes in sympathetic and vagal modulation, respectively. The unpaired t test (or Mann-Whitney rank sum test when appropriate) was used in the statistical analysis. In the aging process, the distributions of patterns (SE) remain similar to young subjects. However, the regularity is significantly different; the patterns are more repetitive in the old group (a decrease of CI and NCI). The amounts of pattern types are different: 0V is increased and 2LV and 2ULV are reduced in the old group. These differences indicate marked change of autonomic regulation. The CE and SA are feasible techniques to detect alteration in autonomic control of heart rate in the old group.
| Original language | English |
|---|---|
| Pages (from-to) | 229-235 |
| Number of pages | 7 |
| Journal | Internal and Emergency Medicine |
| Volume | 7 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - Jun 2012 |
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Keywords
- Aging
- Conditional entropy
- Heart rate variability
- Nonlinear analysis
- Symbolic analysis
ASJC Scopus subject areas
- Emergency Medicine
- Internal Medicine
Cite this
Aging reduces complexity of heart rate variability assessed by conditional entropy and symbolic analysis. / Takahashi, Anielle C M; Porta, Alberto; Melo, Ruth C.; Quitério, Robison J.; da Silva, Ester; Borghi-Silva, Audrey; Tobaldini, Eleonora; Montano, Nicola; Catai, Aparecida M.
In: Internal and Emergency Medicine, Vol. 7, No. 3, 06.2012, p. 229-235.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Aging reduces complexity of heart rate variability assessed by conditional entropy and symbolic analysis
AU - Takahashi, Anielle C M
AU - Porta, Alberto
AU - Melo, Ruth C.
AU - Quitério, Robison J.
AU - da Silva, Ester
AU - Borghi-Silva, Audrey
AU - Tobaldini, Eleonora
AU - Montano, Nicola
AU - Catai, Aparecida M.
PY - 2012/6
Y1 - 2012/6
N2 - Increasing age is associated with a reduction in overall heart rate variability as well as changes in complexity of physiologic dynamics. The aim of this study was to verify if the alterations in autonomic modulation of heart rate caused by the aging process could be detected by Shannon entropy (SE), conditional entropy (CE) and symbolic analysis (SA). Complexity analysis was carried out in 44 healthy subjects divided into two groups: old (n = 23, 63 ± 3 years) and young group (n = 21, 23 ± 2). It was analyzed SE, CE [complexity index (CI) and normalized CI (NCI)] and SA (0V, 1V, 2LV and 2ULV patterns) during short heart period series (200 cardiac beats) derived from ECG recordings during 15 min of rest in a supine position. The sequences characterized by three heart periods with no significant variations (0V), and that with two significant unlike variations (2ULV) reflect changes in sympathetic and vagal modulation, respectively. The unpaired t test (or Mann-Whitney rank sum test when appropriate) was used in the statistical analysis. In the aging process, the distributions of patterns (SE) remain similar to young subjects. However, the regularity is significantly different; the patterns are more repetitive in the old group (a decrease of CI and NCI). The amounts of pattern types are different: 0V is increased and 2LV and 2ULV are reduced in the old group. These differences indicate marked change of autonomic regulation. The CE and SA are feasible techniques to detect alteration in autonomic control of heart rate in the old group.
AB - Increasing age is associated with a reduction in overall heart rate variability as well as changes in complexity of physiologic dynamics. The aim of this study was to verify if the alterations in autonomic modulation of heart rate caused by the aging process could be detected by Shannon entropy (SE), conditional entropy (CE) and symbolic analysis (SA). Complexity analysis was carried out in 44 healthy subjects divided into two groups: old (n = 23, 63 ± 3 years) and young group (n = 21, 23 ± 2). It was analyzed SE, CE [complexity index (CI) and normalized CI (NCI)] and SA (0V, 1V, 2LV and 2ULV patterns) during short heart period series (200 cardiac beats) derived from ECG recordings during 15 min of rest in a supine position. The sequences characterized by three heart periods with no significant variations (0V), and that with two significant unlike variations (2ULV) reflect changes in sympathetic and vagal modulation, respectively. The unpaired t test (or Mann-Whitney rank sum test when appropriate) was used in the statistical analysis. In the aging process, the distributions of patterns (SE) remain similar to young subjects. However, the regularity is significantly different; the patterns are more repetitive in the old group (a decrease of CI and NCI). The amounts of pattern types are different: 0V is increased and 2LV and 2ULV are reduced in the old group. These differences indicate marked change of autonomic regulation. The CE and SA are feasible techniques to detect alteration in autonomic control of heart rate in the old group.
KW - Aging
KW - Conditional entropy
KW - Heart rate variability
KW - Nonlinear analysis
KW - Symbolic analysis
UR - http://www.scopus.com/inward/record.url?scp=84862231942&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84862231942&partnerID=8YFLogxK
U2 - 10.1007/s11739-011-0512-z
DO - 10.1007/s11739-011-0512-z
M3 - Article
C2 - 21253879
AN - SCOPUS:84862231942
VL - 7
SP - 229
EP - 235
JO - Internal and Emergency Medicine
JF - Internal and Emergency Medicine
SN - 1828-0447
IS - 3
ER -