ABSTRACT
BACKGROUND: The worldwide pandemic SARS-CoV-2 infection is associated with clinical course including a very broad spectrum of clinical manifestations, including death. Several studies and meta-analyses have evaluated the role of hypertension on prognosis, but with important limitations and conflicting results. Therefore, we decided to perform a new meta-analysis of the observational studies that explored the relationship between pre-existing hypertension and mortality risk in patients with SARS-CoV-2 infection, using more stringent inclusion criteria to overcome the limitations inherent previous meta-analyses. METHODS: A systematic search of the on-line databases available up to 31 March 2022 was conducted, including peer-reviewed original articles, involving the adult population, where the role of hypertension on mortality due to SARS-CoV-2 infection was determined by Cox-proportional hazard models. Pooled hazard ratio (HR) was calculated by a random effect model. Sensitivity, heterogeneity, publication bias, subgroup and meta-regression analyses were performed. RESULTS: Twenty-six studies (222,083 participants) met the pre-defined inclusion criteria. In the pooled analysis, pre-existing hypertension was significantly associated with mortality due to SARS-CoV-2 infection, both in unadjusted and adjusted models (HR: 1.55; 95% CI: 1.22 to 1.97). However, in separate analyses including results adjusted for crucial and strong predictors of mortality during SARS-CoV-2 infection (e.g. body weight), the association disappeared. CONCLUSIONS: The results of this meta-analysis indicate that pre-existing hypertension is not an independent predictor of mortality during SARS-CoV-2 infection. Further studies should nevertheless be carried out worldwide to evaluate this role, independent of, or in interaction with, other confounders that may affect the mortality risk.
ABSTRACT
AIMS: In the course of the COVID-19 pandemic, multiple suggestions have been delivered through websites and social media referring to natural substances and various kinds of supplements with thaumaturgical properties in preventing and/or fighting the coronavirus infection. Indeed, there is no clinical trial evidence that a dietary or pharmacological supplementation of any particular substance will increase the effectiveness of the immune defences. There are however three nutritional issues that deserve special attention under the present circumstances, namely vitamin D deficiency, excess salt intake and inappropriate alcohol consumption. Here is a short review of the current knowledge about the possible role of these factors in the immunity defence system and their potential impact on the modulation of the immune response to SARS-COV2 infection. DATA SYNTHESIS: For all of these factors there is convincing evidence of an impact on the immune defence structure and function. In the absence of RCT demonstration that increased ingestion of any given substance may confer protection against the new enemy, special attention to correction of these three nutritional criticisms is certainly warranted at the time of COVID pandemic. CONCLUSIONS: We propose that the inappropriate intake of salt and alcohol and the risk of inadequate vitamin D status should be object of screening, in particular in subjects at high mortality risk from SARS-COV 2 infection, such as institutionalised elderly subjects and all those affected by predisposing conditions.