Assistant Professor University of New Mexico School of Medicine Albuquerque, New Mexico, United States
Abstract Body : Fatty liver disease (FLD) is a growing medical concern among children and adolescents, affecting up to possibly 10% of the pediatric population. FLD is associated with the metabolic syndrome (obesity, type II diabetes, hypertension). If FLD is progresses, individuals may develop steatohepatitis and hepatocarcinoma. FLD is linked to reduced bone mineral density (BMD) in children, likely due to some combination of systemic inflammation, reduced availability of vitamin D, and sedentary lifestyles. Additionally, excess visceral adipose tissue (VAT) is linked to early-life stress, including small weight for gestational age. Stress suffered during early life may lead to the accumulation of VAT and the development of FLD.
In this study, we examine whether liver radiodensity is associated with reduced BMD among 691 individuals aged 0.5-21 years in a post-mortem CT (PMCT) sample from the Office of the Medical Investigator in New Mexico. Liver radiodensity was quantified from CT scans using Hounsfield Units (HU), a measure of tissue attenuation. Lower liver HU reflects FLD, as this condition is characterized by the accumulation of adipose tissue in the liver. Liver HU was measured at three sites on the right lobe of the liver in a single transverse image and then averaged together. Linear regression was used to examine relationships between liver HU and several independent variables, including physiological stress in early life, BMD, and muscle density.
Lower liver HU is significantly associated with FLD diagnosed at autopsy, reduced BMD and muscle density, increased VAT, and increased likelihood of cardiomegaly. These results bolster the relationship between FLD and reduced BMD in children and adolescents. FLD continues to increase in prevalence among juveniles, most likely due to increasing rates of early childhood obesity, which is linked with poor nutrition, sedentary behavior, and experiences of early-life stress. Clinically, FLD is most accurately diagnosed with fine needle biopsy, but at a minimum extensive bloodwork is typically performed for pediatric patients. The use of medical imaging is typically limited to ultrasound to identify lesions and masses. While the method used in this study has restricted clinical application, it can be applied to numerous CT scans databased for research purposes to better understand the prevalence of FLD and its comorbidities among children and adolescents.
