Sedentary behavior is associated with poor sleep quality during the COVID-19 pandemic, and physical activity mitigates its adverse effects.

BACKGROUND: We aimed to evaluate the association of sedentary behavior (SB) and moderate to vigorous leisure-time physical activity (MVPA) with sleep quality during the COVID-19 pandemic. METHODS: Cross-sectional, population-based study in adults, conducted from October to December 2020 in the Iron Quadrangle region, Brazil. The outcome was sleep quality, evaluated with the Pittsburgh Sleep Quality Index. SB was assessed by self-report of total sitting time, before and during the pandemic. Individuals with ≥ 9 h of total sitting time were classified as SB. In addition, the ratio of time spent in MVPA to time in SB was analyzed. A contrasted directed acyclic graph (DAG) model was constructed to adjust logistic regression models. RESULTS: A total of 1629 individuals were evaluated, the prevalence of SB before the pandemic was 11.3% (95%CI: 8.6-14.8), and during the pandemic 15.2% (95%CI: 12.1-18.9). In multivariate analysis, the chance of poor sleep quality was 77% higher in subjects with SB ≥ 9 h per day (OR: 1.77; 95% CI: 1.02-2.97). Furthermore, a one-hour increase in SB during the pandemic, increased the chance of poor sleep quality by 8% (OR: 1.08; 95%CI 1.01-1.15). In the analysis of the ratio of MVPA per SB in individuals with SB ≥ 9 h, practicing 1 min of MVPA per hour of SB reduces the chance of poor sleep quality by 19% (OR: 0.84; 95%CI: 0.73-0.98). CONCLUSION: SB during the pandemic was a factor associated with poor sleep quality, and the practice of MVPA can reduce the effects of SB.

The exogenous surfactant pre-treatment attenuates ventilator-induced lung injury in adult rats.

Mechanical ventilation is an essential supportive therapy in the treatment of critical patients, and it aims to maintain adequate gas exchange; however, it can also contribute to inflammation and oxidative stress, thus leading to lung injury. We tested the hypothesis that exogenous surfactant administration will be protective against ventilator-induced lung injury in adult healthy Wistar rats both because of its anti-inflammatory properties as well as its role in preventing alveolar collapse at end-expiration. Thus, the effect of intranasal instillation of a bovine exogenous surfactant was tested in Wistar rats submitted to mechanical ventilation. The animals were divided into four groups: (1) CONTROL; (2) SURFACTANT; (3) Mechanical ventilation (MV); (4) MV with pre-treatment with surfactant (MVSURFACTANT). The MV and MVSURFACTANT were submitted to MV with high tidal volume (12 mL/kg) for 1 h. After the experimental protocol, all animals were euthanized and the arterial blood, bronchoalveolar lavage fluid and lungs were collected for biochemical, immunoenzymatic assay, arterial blood gases, and morphometric analyzes. The Wistar rats that received exogenous surfactant (Survanta®) by intranasal instillation before MV demonstrated reduced levels of leukocytes, inflammatory biomarkers such as CCL2, IL-1, IL-6 and TNF-α. Furthermore, it prevented oxidative damage by reducing lipid peroxidation and protein carbonylation as well as histological pattern changes of pulmonary parenchyma. Our data indicate that exogenous surfactant attenuated lung inflammation and redox imbalance induced by mechanical ventilation in healthy adult rats suggesting a preventive effect on ventilator-induced lung injury.