Systematic review of the effect of metabolic syndrome on outcomes due to acute respiratory distress syndrome: a protocol

INTRODUCTION: Acute respiratory distress syndrome (ARDS) is a life-threatening condition commonly seen in the intensive care unit. COVID-19 has dramatically increased the incidence of ARDS—with this rise in cases comes the ability to detect predisposing factors perhaps not recognised before, such as metabolic syndrome (MetS) and its associated conditions (hypertension, obesity, dyslipidaemia and type 2 diabetes mellitus). In this systematic review, we seek to describe the complex relationship between MetS, its associated conditions and ARDS (including COVID-19 ARDS). METHODS AND ANALYSIS: A systematic search of PubMed, Embase, Cochrane Central Register of Controlled Trials, CINAHL and Web of Science will be conducted. The population of interest is adults with ARDS and MetS (as defined according to the study author recognising that MetS definitions vary) or any MetS-associated condition. The control group will be adult patients with ARDS without MetS or any individual MetS-associated condition. We will search studies published in English, with a date restriction from the year 2000 to June 2023 and employ the search phrases ‘metabolic syndrome’, ‘acute respiratory distress syndrome’ and related terms. Search terms including ‘dyslipidaemia’, ‘hypertension’, ‘diabetes mellitus’ and ‘obesity’ will also be utilised. Outcomes of interest will include mortality (in-hospital, ICU, 28-day, 60-day and 90-day), days requiring mechanical ventilation and hospital and/or ICU length of stay. Study bias will be assessed using the NIH Bias Scale. ETHICS AND DISSEMINATION: Ethical approval is not required because this study includes previously published and publicly accessible data. Findings from this review will be disseminated via publication in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42023405816.