Previous studies have suggested that nonalcoholic fatty liver disease (NAFLD) is associated with lower bone mineral density (BMD), but data are limited especially in Western countries.
The cross-sectional study was conducted to assess the association between NAFLD and BMD. In this study, the author used the National Health and Nutrition Survey (NHANES) III dataset, and examined the association in the United States population.
6,126 participants from 40 to 75 year old were selected after excluding people with hepatitis virus serology, elevated alcohol consumption, or decreased renal function, and pregnant women. The exposure, NAFLD, was defined as having moderate to severe hepatic steatosis. The prevalence of NAFLD was 24.9% among the selected participants. Multivariate linear regression with the outcome of BMD was conducted. After controlling for gender/menopausal status, race, age and BMI, the final model did not show a statistically significant NAFLD effect on BMD (beta coefficient: -0.007, 95%CI: -0.016, 0.003).
In the secondary analysis, using serum alanine aminotransferase (ALT) level, NAFLD group was further categorized into high ALT NAFLD group and normal ALT NAFLD group. These two groups were used as exposures, and non-NAFLD group was used as a reference group. After controlling for gender/menopausal status, race, age and BMI, the final model showed that high ALT NAFLD has statistically significant negative effect on BMD (beta coefficient: -0.051, 95% CI: -0.081, -0.020) at the overall average BMI level, 27 kg/m2. The interaction term between high ALT NAFLD and BMI showed statistically significant positive coefficient (beta coefficient: 0.004, 95% CI: 0.001, 0.007), which suggests the high ALT NAFLD negative effect is attenuated among higher BMI people.
The primary analysis did not support the hypothesis that NAFLD has an association with lower BMD. The secondary analysis suggested the possible relationship between NAFLD and lower BMD among people with low to normal BMI.
Table of Contents
Background/Literature Review 1
Future Directions 27
Figures and Figure Legends 45
Appendices 50 (Supporting Information 50, SAS Source Codes 56)
About this Master's Thesis
|Committee Chair / Thesis Advisor|
|The Association between Nonalcoholic Fatty Liver Disease and Bone Mineral Density -- Results from the Third National Health and Nutrition Examination Survey (NHANES III) ()||2018-08-28||