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A better understanding of the SARS-CoV-2 virus behavior and possible risk factors implicated in poor outcome has become an urgent need. We performed a systematic review in order to investigate a possible association between body weight and prognosis among patients diagnosed with COVID-19. We searched in Cochrane Library, EMBASE, MEDLINE, WHO-Global Literature on Coronavirus Disease, OpenGrey, and Medrxiv. We used the ROBINS-I tool or Cross-Sectional/Prevalence Study Quality tool from AHRQ, to evaluate the methodological quality of included studies. Nine studies (two prospective cohorts, four retrospective cohorts and three cross-sectional) were included and assessed the relationship between obesity and COVID-19 prognosis. Risk of bias of the included studies ranged from moderate to critical. Clinical and methodological heterogeneity among them precluded meta-analyses. Most of the included studies showed some degree of association to: (a) higher BMI and worse clinical presentation and (b) obesity and need of hospitalization. The results were inconsistent about the impact of obesity on mortality. Based on limited methodological quality studies, obesity seems to predict poor clinical evolution in patients with COVID-19. Further studies with appropriate prospective design are needed to reduce the uncertainty on this evidence., (Copyright © 2020 Peres, Riera, Martimbianco, Ward and Cunha.)

Many studies have provided observational data on the association of obesity and thyroid cancers, but only few of them propose mechanisms that would permit a better understanding of the causal molecular mechanisms of this association. Considering that there is an increasing incidence of both obesity and thyroid cancers, we need to summarize and link recent studies in order to characterize and understand the contribution of obesity-related factors that might affect thyroid cancer development and progression. Adipose tissue is involved in many vital processes, including insulin sensitivity, angiogenesis, regulation of energy balance, activation of the complement system, and responses such as inflammation. Although these processes have their own molecular pathways, they involve the same molecules through which obesity and adipose tissue might exert their roles in carcinogenesis, not only affecting MAPK and PI3K or even insulin pathways, but also recruiting local inflammatory responses that could result in disease formation and progression. This review describes five important issues that might explain the link between excessive weight and thyroid cancer: thyroid hormones, insulin resistance, adipokines, inflammation, and sexual hormones., (© 2014 Society for Endocrinology.)

The melanocortin system in the hypothalamus controls food intake and energy expenditure. Its disruption causes severe obesity in mice and humans. cAMP-response element-binding protein 1 (CREB1) has been postulated to play an important role downstream of the melanocortin-4 receptor (MC4R), but this hypothesis has never been confirmed in vivo. To test this, we generated mice that lack CREB1 in SIM1-expressing neurons, of the paraventricular nucleus (PVN), which are known to be MC4R-positive. Interestingly, CREB1(ΔSIM1) mice developed obesity as a result of decreased energy expenditure and impairment in maintaining their core body temperature and not because of hyperphagia, defining a new role for CREB1 in the PVN. In addition, the lack of CREB1 in the PVN caused a reduction in vasopressin expression but did not affect adrenal or thyroid function. Surprisingly, MC4R function tested pharmacologically was normal in CREB1(ΔSIM1) mice, suggesting that CREB1 is not required for intact MC4R signaling. Thus CREB1 may affect other pathways that are implicated in the regulation of body weight.