Date Published: July 27, 2017
Publisher: Public Library of Science
Author(s): Marcio Clementino de Souza Santos, Luiz Carlos de Lima Silveira, Sílvia Cristina Garcia Moura-Tonello, Alberto Porta, Aparecida Maria Catai, Givago da Silva Souza, Tohru Minamino.
To evaluate the heart rate variability (HRV) in patients with multibacillary leprosy using dynamic linear and nonlinear analysis.
Twenty-one leprosy patients (mean age: 39.14 ±10.58 years) and 21 healthy subjects (mean age: 36.24 ± 12.64 years) completed the sample. Heart rate variability recording was performed by a Polar RS800 CX heart monitor during a period of 15 min in the supine position and 15 min in a sitting position. Analysis of HRV was performed by frequency domain from high frequency (HF) and low frequency (LF) spectral indexes in absolute and normalized units. The nonlinear analysis of HRV was calculated using symbolic analysis (0V%, 1V%, 2LV% and 2UV% indexes), Shannon entropy (SE) and normalized complexity index (NCI).
Linear analysis: both groups showed higher HF values (p < 0.05) and smaller LF values (p < 0.05) in supine than in sitting position. The leprosy patients showed higher LF values (p < 0.05) and smaller HF values (p < 0.05) compared to the controls on supine position. Symbolic analysis: leprosy patients had higher 0V% values (p < 0.05), smaller 2LV% values (p < 0.05) and 2UV % values compared to healthy subjects on both positions. The 1V % had higher values (p < 0.05) for leprosy patients than for controls in the sitting position. The control subjects had smaller 0V % values (p < 0.05), and higher 2UV % values (p < 0.05) in the supine position compared to the sitting position. Leprosy patients had higher 2UV index values (p < 0.05) in the supine position compared to the sitting position. In the complexity analysis, leprosy patients had smaller SE and NCI values (p < 0.05) than the control in the supine position. There was no difference between the SE and NCI values of leprosy and the control subjects in the sitting position. The control subjects had higher SE and NCI values (p < 0.05) in the supine position than in the sitting position. Leprosy patients had higher sympathetic modulation and smaller vagal modulation than controls, indicating less HRV and cardiac modulation with lower complexity. The control group displayed significant HRV differences in response to position changes while leprosy patients had fewer HRV differences after the same postural change. An analysis of HRV with linear and non-linear dynamics proved to be a reliable method and promising for the investigation of autonomic dysfunction in patients with multibacillary leprosy.
Leprosy is a chronic, infectious disease caused by Mycobacterium leprae . More than 200,000 new cases are detected every year, most of them in developing countries such as India and Brazil . The disease leads to several disabilities, including motor, sensory, and autonomic impairments [3, 4]. These complications affect the quality of life of the patients and are associated with high treatment and rehabilitation costs.
Table 1 describes the physical features and information about the drug therapy of the leprosy patients.
In the present investigation, we observed that multibacillary leprosy patients had changes in HRV using linear and non-linear methods, reflecting changes in the autonomic control of the heart function. We found in the patients an increase of the sympathetic modulation and a decrease of the vagal modulation on the heart as well as a reduced complexity of HRV.
The leprosy group had higher cardiac sympathetic modulation, reduced vagal modulation on the heart and reduced complexity of RRi than the control group, indicating lower HRV. In response to postural change from supine to sitting position, the leprosy group showed a lower change to this stimulus because even in the supine it already had high sympathetic modulation.