ABSTRACT
Social isolation and feelings of loneliness are related to higher mortality and morbidity. Evidence from studies conducted during space missions, in space analogs, and during the COVID-19 pandemic underline the possible role of the autonomic nervous system in mediating this relation. Indeed, the activation of the sympathetic branch of the autonomic nervous system enhances the cardiovascular response and activates the transcription of pro-inflammatory genes, which leads to a stimulation of inflammatory activation. This response is adaptive in the short term, in that it allows one to cope with a situation perceived as a threat, but in the long term it has detrimental effects on mental and physical health, leading to mood deflection and an increased risk of cardiovascular disease, as well as imbalances in immune system activation. The aim of this narrative review is to present the contributions from space studies and insights from the lockdown period on the relationship between social isolation and autonomic nervous system activation, focusing on cardiovascular impairment and immune imbalance. Knowing the pathophysiological mechanisms underlying this relationship is important as it enables us to structure effective countermeasures for the new challenges that lie ahead: the lengthening of space missions and Mars exploration, the specter of future pandemics, and the aging of the population.
ABSTRACT
Multiple System Atrophy (MSA) is a rare neurodegenerative disease, clinically defined by a combination of autonomic dysfunction and motor involvement, that may be predominantly extrapyramidal (MSA-P) or cerebellar (MSA-C). Although dementia is generally considered a red flag against the clinical diagnosis of MSA, in the last decade the evidence of cognitive impairment in MSA patients has been growing. Cognitive dysfunction appears to involve mainly, but not exclusively, executive functions, and may have different characteristics and progression in the two subtypes of the disease (i.e., MSA-P and MSA-C). Despite continued efforts, combining in-vivo imaging studies as well as pathological studies, the physiopathological bases of cognitive involvement in MSA are still unclear. In this view, the possible link between cardiovascular autonomic impairment and decreased cognitive performance, extensively investigated in PD, needs to be clarified as well. In the present study, we evaluated a cohort of 20 MSA patients (9 MSA-P, 11 MSA-C) by means of a neuropsychological battery, hemodynamic assessment (heart rate and arterial blood pressure) during rest and active standing and bedside autonomic function tests assessed by heart rate variability (HRV) parameters and sympathetic skin response (SSR) in the same experimental session. Overall, global cognitive functioning, as indicated by the MoCA score, was preserved in most patients. However, short- and long-term memory and attentional and frontal-executive functions were moderately impaired. When comparing MSA-P and MSA-C, the latter obtained lower scores in tests of executive functions and verbal memory. Conversely, no statistically significant difference in cardiovascular autonomic parameters was identified between MSA-P and MSA-C patients. In conclusion, moderate cognitive deficits, involving executive functions and memory, are present in MSA, particularly in MSA-C patients. In addition, our findings do not support the role of dysautonomia as a major driver of cognitive differences between MSA-P and MSA-C.
ABSTRACT
Chronic pain and dysautonomic symptoms deteriorate Systemic sclerosis (SSc) patients' health-related quality of life with serious repercussions on social life and even on sleep. Heart Rate Variability (HRV) analysis can identify cardiovascular autonomic control impairment in subclinical condition. The aim of the present observational cross-sectional study was to assess the relationship between dysautonomic symptoms, quality of life status and cardiovascular autonomic profile. ECG and respiration were recorded at rest in 20 SSc patients. HRV analysis was performed using two different approaches: Linear spectral analysis and non-linear symbolic analysis. Pain was evaluated using the Numeric Rating Scale (NRS) and 3 questionnaires were administered for the evaluation of sleep quality (PSQI), mood tone (PHQ-9) and disability (HAQ). We found that sleep impairment was related to sympathetic predominance at rest measured as low-frequency/high-frequency ratio (LF/HF) (r = 0.48 and p = 0.033); poorer sleep quality was related to higher pain values (r = 0.48 and p = 0.034) and depressive symptoms (r = 0.82 and p < 0.01); higher pain scores were related to higher cardiovascular vagal modulation and higher disability indexes (r = 0.47 and p = 0.038 & r = 0.55 and p = 0.012, respectively). In conclusion dysautonomia and chronic pain showed a severe impact on sleep quality and disability with a consequent worsening of depressive symptom in our cohort of SSc patients.
