Background: The association of central obesity with higher rates of mortality is not well studied. This study evaluates the association between waist-to-height ratio (WHtR), as a measure of central obesity, with mortality. Methods: Documents were retrieved from PubMed, Web of Science, Scopus, and Google Scholar databases until May 2022. Data were extracted from cohort studies reporting effect size (hazard ratio (HR)) regarding the association between WHtR as a continuous (per 1 SD increment) or categorical (highest/lowest) measure and all-cause and cause-speci c mortality. Screening of included studies was performed independently by two authors. Moreover, the quality assessment of included studies was performed based on the Newcastle-Ottawa assessment scale. Finally, random effect meta-analysis was performed to pool the data, and the outcomes' certainty level was assess based on the GRADE criteria Results: Of the 815 initial studies, 20 were included in the meta-analysis. Random effect meta-analysis showed that in the general population, the all-cause mortality HRs for categorical and continuous measurements of WHtR increased signi cantly by 23% (HR:1.23; 95%CI: 1.04-1.41) and 16% (HR:1.16; 95%CI: 1.07-1.25), respectively. Moreover, the hazard of cardiovascular (CVD) mortality increased signi cantly for categorical and continuous measurements of WHtR by 39% (HR:1.39; 95%CI: 1.18-1.59) and 19% (HR:1.19; 95%CI:1.07-1.31). The quality assessment score of all included studies was high.Conclusions: Higher levels of WHtR, indicating central obesity, were associated with an increased hazard of CVD and all-cause mortality. This measure can be used in the clinical setting as a simple tool for predicting mortality.
BackgroundCentral obesity, also known as visceral or abdominal obesity, happens when fat tissue accumulation in the body's central part increases with aging (1,2). According to the reports, the prevalence of central obesity has risen over time. It has been predicted that 80.0% of women and over half of men (55.6%) in the United States will have abdominal obesity by 2030 (3). Central obesity has become a global concern since it is linked to several unpleasant health conditions. On top of the general hazards reported for obesity, such as cardiovascular diseases (2,4-12) and diabetes (1,13,14), it has been revealed that central obesity, in particular, is a signi cant risk factor for several health complications, including chronic kidney disease (CKD) (15,16), the decline in glomerular ltration rate (GFR) (17), diabetic kidney disease (18), obstructive sleep apnea syndrome (OSAS) (19), metabolic syndrome (20-25), chronic obstructive pulmonary disease (COPD) (26), liver cancer (2,27), biliary tract cancer (2,28), heart failure with preserved ejection fraction (HFpEF) (29), endothelial dysfunction (30), and nally, premature death (2,22,31). Regarding the measurement of central obesity, approaches using body mass index (BMI) sometimes fail to specify whether high BMI is related to abdominal obesity or not since BMI doe...