The entropy of RR intervals is associated to gestational age in full-term newborns with adequate weight for gestational age.

Introduction: The variability of successive RR intervals has been pointed out as an indicator of systemic homeostasis. The entropy of successive RR intervals is associated with a greater adaptive capacity, which is essential after childbirth, characterized by a change from an intrauterine environment that constantly adapts to the fetal demands, to an extrauterine environment that requires constant biological adaptations by the neonate.

Objectives: To analyze the association between gestational age (GA) and the entropy of RR intervals in term infants with adequate birth weight in the first hours of extrauterine life.

Sarcopenia is associated to an impaired autonomic heart rate modulation in community-dwelling old adults.

Purpose: The aims of this study were to compare the autonomic heart control parameters from sarcopenic and non-sarcopenic community-dwelling elders.

Methods: This is a cross-sectional study including 76 community-dwelling old adults, which was clinically stratified as sarcopenic or non-sarcopenic, according to the current recommendations. They were submitted to 5-min recordings of successive RR intervals.

The smoking habit negatively influences autonomic heart control in community-dwelling elderly adults.

Objective: The present study aimed to analyze the influence of smoking on heart autonomic control in elderly adults who did and did not smoke.

Methods: In a population-based study, all community-dwelling elderly adults (≥60 years old) from Aiquara, Bahia, Brazil, were invited to participate in the study. Two-hundred-thirty-two (232) elderly adults provided information about their smoking habits and underwent 5-min recordings of successive RR intervals.