Liver Diseases
Conditions
Keywords
Obese, MRS, hepatic triglyceride content, MR spectroscopy
Brief summary
The purpose of this study is to see how effective the investigators' optimized magnetic resonance spectroscopy (MRS) sequence in quantifying hepatic triglyceride content (HTGC) to enhance MRS as a diagnostic tool in non-alcohol fatty liver disease (NAFLD).
Detailed description
One way to gauge MRS as an effective diagnostic tool is by looking at the reproducibility of the liver fat measurements on subjects by calculating the coefficient of variation (CV). This study assesses the modified MRS sequence, using both breath holds and free breathing. The HTGC levels are measured twice in the same individuals on two independent events separated by 10 minutes. Subjects are then given a high fat, high carbohydrate meal of Pizza Hut pizza, Pepsi, and Oreo cookies. Two hours after eating the meal, the subjects return to the scanner and repeat all MRS scans.
Interventions
None listed
Sponsors
Washington University School of Medicine
Study design
Observational model
COHORT
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Obese
Exclusion criteria
* Diabetes * Pregnant
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| The Reproducibility of the Hepatic Triglyceride Content Measurement by MRS. | 6 months | We compared three 1H-Magnetic Resonance Spectroscopy sequences: A Standard Siemens sequence, and an optimized sequence with either breath-holds or free-breathing. Repeat scans were done with the subject briefly removed from and returned to the scanner between scans. The results given are coefficients of variation of the triglyceride signal divided by the water signal. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| The Hepatic Triglyceride Content Pre- and Post-prandial. | after a 12 hour fast and 2 hours post-prandial | We compared the intrahepatic triglyceride content in subjects after a 12 hour fast and 2 hours after eating a high fat, high carbohydrate meal. The measure reported here is for the pre and post prandial results given as the ratio of triglyceride signal to water signal. After showing its reliability, we chose to use the results from the optimized breath-hold sequence. |
| T2 (Spin-spin Relaxation Time) Ratios of Triglyceride/Water | baseline cross-sectional measurements | T2 (spin-spin relaxation time) ratios of triglyceride/water using optimized PRESS sequences |
Countries
United States
Participant flow
Recruitment details
Subjects were recruited through the Center for Human Nutrition (CHN) beginning in July, 2009. Many had previously been enrolled in other CHN studies. The final subject was tested in December, 2009.
Pre-assignment details
All enrolled subjects completed the study.
Participants by arm
| Arm | Count |
|---|---|
| NAFLD Non-diabetic, obese with diagnosed NAFLD (hepatic triglyceride content (HTGC) greater or equal to 5.5%) | 5 |
| Non-NAFLD Non-diabetic, obese with no previous diagnosis of NAFLD | 9 |
| Total | 14 |
Baseline characteristics
| Characteristic | Non-NAFLD | Total | NAFLD |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 1 Participants | 1 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 8 Participants | 13 Participants | 5 Participants |
| Age, Continuous | 46 years STANDARD_DEVIATION 12 | 45 years STANDARD_DEVIATION 12 | 43 years STANDARD_DEVIATION 13 |
| Region of Enrollment United States | 9 participants | 14 participants | 5 participants |
| Sex: Female, Male Female | 4 Participants | 8 Participants | 4 Participants |
| Sex: Female, Male Male | 5 Participants | 6 Participants | 1 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 5 | 0 / 9 |
| serious Total, serious adverse events | 0 / 5 | 0 / 9 |
Outcome results
Primary
The Reproducibility of the Hepatic Triglyceride Content Measurement by MRS.
We compared three 1H-Magnetic Resonance Spectroscopy sequences: A Standard Siemens sequence, and an optimized sequence with either breath-holds or free-breathing. Repeat scans were done with the subject briefly removed from and returned to the scanner between scans. The results given are coefficients of variation of the triglyceride signal divided by the water signal.
Time frame: 6 months
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| NAFLD | The Reproducibility of the Hepatic Triglyceride Content Measurement by MRS. | Siemens sequence | 13.0 coefficient of variation | Standard Error 9.6 |
| NAFLD | The Reproducibility of the Hepatic Triglyceride Content Measurement by MRS. | Optimized sequence | 4.4 coefficient of variation | Standard Error 3.9 |
| Non-NAFLD | The Reproducibility of the Hepatic Triglyceride Content Measurement by MRS. | Siemens sequence | 23.5 coefficient of variation | Standard Error 1.1 |
| Non-NAFLD | The Reproducibility of the Hepatic Triglyceride Content Measurement by MRS. | Optimized sequence | 9.7 coefficient of variation | Standard Error 0.1 |
Secondary
T2 (Spin-spin Relaxation Time) Ratios of Triglyceride/Water
T2 (spin-spin relaxation time) ratios of triglyceride/water using optimized PRESS sequences
Time frame: baseline cross-sectional measurements
Population: This analysis was per protocol.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| NAFLD | T2 (Spin-spin Relaxation Time) Ratios of Triglyceride/Water | Low IHTG | 0.9 ratio | Standard Deviation 0.1 |
| NAFLD | T2 (Spin-spin Relaxation Time) Ratios of Triglyceride/Water | Medium IHTG | 1.1 ratio | Standard Deviation 0.1 |
| NAFLD | T2 (Spin-spin Relaxation Time) Ratios of Triglyceride/Water | High IHTG | 1.1 ratio | Standard Deviation 0.1 |
Comparison: null hypothesis was that the T2 ratio would not depend on level of intrahepatic triglyceride (IHTG) and would be equal for the low and medium IHTG categories.p-value: 0.006t-test, 2 sided
Comparison: null hypothesis was that the T2 ratio would not depend on level of intra-hepatic triglyceride (IHTG) and would be equal for the low (\<5%) and high (\>10%) IHTG categories.p-value: <0.0001t-test, 2 sided
Comparison: The null hypothesis was that there would be no difference in T2 relaxation ratios for varying levels of intra-hepatic triglyceride (IHTG). Thus the medium (5 - 10%) and high (\<10%) IHTG groups would not be statistically different with regard to average T2 ratio.p-value: 0.93t-test, 2 sided
Secondary
The Hepatic Triglyceride Content Pre- and Post-prandial.
We compared the intrahepatic triglyceride content in subjects after a 12 hour fast and 2 hours after eating a high fat, high carbohydrate meal. The measure reported here is for the pre and post prandial results given as the ratio of triglyceride signal to water signal. After showing its reliability, we chose to use the results from the optimized breath-hold sequence.
Time frame: after a 12 hour fast and 2 hours post-prandial
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| NAFLD | The Hepatic Triglyceride Content Pre- and Post-prandial. | fasting | 30 ratio | Standard Error 12 |
| NAFLD | The Hepatic Triglyceride Content Pre- and Post-prandial. | post-prandial | 27 ratio | Standard Error 9 |
| Non-NAFLD | The Hepatic Triglyceride Content Pre- and Post-prandial. | fasting | 8 ratio | Standard Error 7 |
| Non-NAFLD | The Hepatic Triglyceride Content Pre- and Post-prandial. | post-prandial | 8 ratio | Standard Error 7 |
Comparison: As there was no a priori reason for the level of IHTG to impact this measurement we compared the pre and post-prandial results for all subjects whose data were of sufficient quality (N=12). These results are comparing the two categories of fasting and post-prandial. Null hypothesis was that there would be no difference in IHTG before and after a high fat, high carbohydrate meal.p-value: 0.097t-test, 2 sided