Abstract and Introduction
Background & Aims: While several anthropometric measures predict liver disease, the waist-hip ratio (WHR) has shown superiority in previous studies. We analysed independent and joint associations of waist circumference (WC) and hip circumference (HC) with liver disease and liver-related risk factors.
Methods: Cross-sectional study (n = 6619) and longitudinal cohort (n = 40 923) comprised individuals from Health 2000 and FINRISK 1992–2012 studies. Prevalent and viral liver diseases were excluded. Longitudinal cohort was linked with national healthcare registers for severe incident liver disease. Linear regression and Cox proportional hazards models were used to analyse anthropometric, lifestyle, metabolic and bioimpedance-related parameters; liver enzymes; and 59 liver-related genetic risk variants.
Results: WC and HC showed independent and opposite associations with both liver enzymes and incident liver disease among men (HR for liver disease: WC, 1.07, 95% CI 1.03–1.11; HC, 0.96, 95% CI 0.92–0.99; P-range .04 to <.001) and women (HR for liver diseases: WC, 1.06, 95% CI 1.02–1.10; HC, 0.93, 95% CI 0.89–0.98; P-range .005 to .004). HC modified associations between WC and liver enzymes, and between WC and incident liver disease, particularly among men. Liver enzymes and risk of liver disease increased with increasing WC, more so among individuals with high WHR compared to with low WHR. WC and HC jointly reflected both body fat distribution and muscle mass, which was largely mirrored by WHR.
Conclusions: WC and HC exhibit independent and joint associations with liver disease, which are largely reflected by WHR. Both body fat distribution and muscle mass contribute to these anthropometric measures.
In the present era of the obesity epidemic, non-viral chronic liver disease is becoming an increasing health concern and economic burden. Chronic liver disease is usually asymptomatic and may silently progress to cirrhosis and end-stage liver disease, constituting the 11th leading cause of death, worldwide. Early identification of persons at risk for progressive liver disease requires that clinicians are aware of a cluster of risk factors, encompassed under the concept of non-alcoholic fatty liver disease (NAFLD) or metabolic dysfunction-associated fatty liver disease (MAFLD).
Obesity, as measured by the body mass index (BMI), is a risk factor for future severe liver disease; however, the risk effect is small.[4–6] Studies comparing different anthropometric measures consistently report that liver-related outcomes are more strongly associated with measures of abdominal obesity than with BMI.[7–9] Specifically, the waist-hip ratio (WHR) reportedly predicts clinical liver-related outcomes better than waist circumference (WC) alone, BMI, or waist-height ratio.[7–9] However, it remains unclear which liver disease-relevant metabolic, lifestyle or genetic factors are better reflected by WHR than the other anthropometric measures.
WHR includes the measure of hip circumference (HC), which exhibits an independent association with metabolic factors.[10,11] HC can also independently predict all-cause mortality.[12,13] However, the association between HC and liver-related outcomes has been scarcely studied. HC may reflect both muscle mass and subcutaneous adiposity. Indeed, the loss of muscle mass (sarcopenia) has been implicated in the pathophysiology of NAFLD[14–16] and liver-related outcomes.[17,18]
An improved understanding of the anthropometric measures predictive of clinical liver disease will be important for population risk stratification, which in turn is necessary for early identification of persons at risk. In the present population-based study, we aimed to compare the WHR to BMI with regards to their associations with several lifestyle, metabolic and genetic risk factors for liver disease, and to analyse the differential associations with WC and HC. In the second part of this study, we evaluated independent associations and interactions of WC and HC with liver disease.
Liver International. 2021;41(12):2903-2913. © 2021 Blackwell Publishing