Obstructive Sleep Apnea is a common respiratory disorder characterized by recurrent nocturnal episodes of normal breathing interruption due to upper airway total or partial collapse. Obstructive sleep apnea and cardiovascular diseases has similar risk factors, but the first is also a predisposing factor for cardiovascular pathologies independently of individuals demographic characteristics or risk markers. Heart rate variability is a non-invasive method to evaluate the regulation of autonomic nervous system and its a promising marker for health and disease, such as cardiovascular and respiratory diseases. The aim was to review whether heart rate variability is altered in patients with obstructive sleep apnea. We searched in five databases, including BIREME, Cochrane, Scholar Google, MEDLINE/PubMed and Periodics CAPES, and reference lists were also searched. Only cross-sectional studies comparing the heart rate variability of obstructive sleep patients with controls were included. Two authors independently extracted data and assessed trial quality. Twelve studies (513 participants with obstructive sleep apnea and 340 controls) met the inclusion criteria. This review evidence that adults with obstructive sleep apnea may demonstrate diminished vagal tone and higher sympathetic responsiveness.

Objectives Heart rate variability (HRV) is an important physiological measure of the capacity for neurogenic homeostatic regulation, and an indirect measure of emotional processing. We aimed to investigate whether HRV parameters are altered in people with chronic low back pain when compared to healthy controls. Methods We searched on PubMed, Scopus, CINAHL, Web of Science, Cochrane Library, and PsycINFO from inception to January 2018. The inclusion criteria were: patients with non-specific chronic low back pain, absence of radiculopathy, age from 18 to 65 years, and comparison with healthy controls. Data extraction was performed by two independent review authors. The methodological quality of the studies was assessed using the appraisal tool for cross-sectional studies. Results After screening 2,873 potential articles, two studies met the inclusion criteria. Studies were composed of 153 patients with chronic low back pain and 62 healthy controls. An electrocardiogram was used to record HRV and linear methods (time and frequency) were used to analyze the results. The main findings indicate that patients with chronic low back pain have a significant reduction in HRV, with sympathetic predominance compared to healthy controls. Conclusions There is limited evidence suggesting that chronic low back pain patients presented a lower vagal activity evidenced by HRV, when compared to healthy controls. The results of this systematic review should be interpreted with caution due to the restricted number of included studies, small sample sizes and different protocols used to measure HRV. The limited evidence about HRV alterations in low back pain also suggests the need of future studies to investigate if HRV parameters can be a useful measure in chronic pain samples or even if it can be used as an outcome in clinical trials aiming to investigate the effectiveness of interventions based on emotion regulation.

Background: Hereditary transthyretin-mediated (hATTR) amyloidosis with polyneuropathy is a rare, inherited, multisystem, and often fatal disease caused by a variant in transthyretin (TTR) gene. Baseline characteristics of patients, especially anthropometric data, are scarce in the literature, and they are relevant to define effective treatment strategies. Objective: This study aimed to describe baseline demographic, anthropometric, and disease characteristics in a cohort of patients from a reference center in Brazil. Methods: Symptomatic patients not previously included in clinical trials and eligible for treatment were enrolled. Ethnicity, state of residence, age, sex, weight, height, body mass index (BMI), TTR variant, and Polyneuropathy Disability Score (PND) at diagnosis were analyzed. Results: Among the 108 patients enrolled, 58.33% were male, 60.19% were Caucasian, and 83.33% lived in the Southeast region. Mean age was 51.61 (±16.37) years, mean weight was 65.76 (±15.16) kg, mean height was 168.33 (±10.26) cm, and mean BMI was 23.11 (±4.45) kg/m2. The most prevalent variant was V30M (86.11%). Patients with PND score 0 presenting autonomic neuropathy were 14.81%. Patients with PND score I-II and III-IV were 52.78 and 32.41%, respectively. Mean weight and BMI were significantly lower in patients with sensory-motor manifestations. Conclusions: This is the largest cohort of patients in Brazil for whom anthropometric characteristics have been described. Baseline demographic, anthropometric, and disease data indicate that delay in diagnosis of hATTR amyloidosis with polyneuropathy is still a problem and that efforts must be made to expedite diagnosis and maximize opportunities for new disease-modifying treatments.

Search methods for identification of studies Five electronic databases were searched (last search date: January 19, 2018) including BIREME, MEDLINE, Periodicos CAPES, The Cochrane Library and Scholar Google. To ensure that all potential articles were included, an extensive set of search terms was used to