Effects of GLP1-RA on Ectopic Fat Deposition in Chronic Kidney Disease: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effects of GLP1-RA on Ectopic Fat Deposition in Chronic Kidney Disease (NCT05254418), a na phase 2 study. The primary outcome is Changes in Intermuscular Fat Deposition as Assessed by Magnetic Resonance Imaging (MRI)..

2. Clinical Question

The study description also identifies questions about skeletal muscle mitochondrial function, physical performance, and the safety and feasibility of the treatment schedule. The registry lists four outcome measures, but a complete set of outcome results and their analyses is not reported in the registry record. Consequently, the central question can be described from the protocol summary, while the magnitude and precision of any observed change cannot be assessed from the posted results.

3. Trial Design

This completed phase 2 study, sponsored by Vanderbilt University Medical Center, is titled as a pilot and feasibility study of glucagon-like peptide-1 receptor agonists and ectopic fat deposition in CKD. It enrolled seven participants. The registry records the allocation as NA, masking as none, and the model as sequential. The record also identifies that this was not a randomized comparison, so the treatment period should not be interpreted as one arm in a randomized trial with a control arm.

The intervention was dulaglutide injection, described as 1.5 mg per week for 12 weeks. The design included a run-in period, a dulaglutide treatment period, and an observational follow-up period. MRI was planned during the run-in, at the beginning and end of treatment, and at the end of follow-up. The primary endpoint’s timeframe is listed as 16 weeks. These repeated measurements allow the study to describe changes across phases, but without a concurrent control group they cannot separate treatment-associated change from other changes over time.

The registry reports a start date of 2022-03-15, a primary completion date of 2024-05-01, and a status of completed. These dates describe the study record; they do not establish when any particular participant completed each assessment. More detailed information about participant flow, the timing of individual assessments, adherence, or deviations from the planned schedule is not reported in the registry record.

The study’s stated aims include assessing intermuscular fat, mitochondrial function, physical performance, and safety and feasibility. The registry lists four outcome measures but records zero analyses. The primary endpoint is described, but its numerical result, the results for other outcomes, and an inferential analysis are not reported in the registry record. A statistical analysis plan, including any prespecified model or adjustment strategy, is also not reported in the registry record. Accordingly, this design supports a description of the study questions and measurement schedule, but the posted information does not support an estimate of treatment effect with quantified uncertainty.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Changes in Intermuscular Fat Deposition as Assessed by Magnetic Resonance Imaging (MRI)., measured over 16 weeks.

The primary endpoint is change in intermuscular fat deposition, assessed using magnetic resonance imaging (MRI). The registry describes calculating intermuscular fat as the ratio between intermuscular fat volume and muscle volume in the mid-thigh region. It defines the reported change as the end-of-study value minus the baseline value. Under that convention, a negative change indicates a decrease in the measured ratio.

This is a continuous measure: each participant’s value can vary along a scale rather than falling into only a few categories. The registry specifies that the reported summary is a mean with standard deviation, and gives a timeframe of 16 weeks. MRI provides a way to quantify tissue compartments in the specified region, while the ratio expresses fat volume in relation to muscle volume. It is therefore a measure of an imaging-defined feature, not a direct measure of a clinical event or of whole-body fat.

As general statistical context, a mean change describes the average direction and size of change across the observations included in an analysis. A standard deviation describes how spread out individual measurements are around that average; it is not the same as uncertainty in the estimated mean. Repeated MRI assessments are described across study phases, but the registry’s primary endpoint definition focuses on the difference between baseline and end of study.

The numerical mean, standard deviation, participant count contributing to the endpoint, and any confidence interval or test result are not reported in the registry record. The endpoint’s meaning can therefore be explained, but neither the observed direction nor the precision of the change can be evaluated from the posted results.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary outcome is continuous: it is a ratio measured by MRI, and the registry describes summarizing it with a mean and standard deviation. As general statistical context, a mean is the arithmetic average of the observations included in an analysis. It provides a compact description of the group’s average value or average change, but it can be influenced by unusually high or low observations. A standard deviation describes variation among individual observations around the mean. It does not directly describe how precisely the mean has been estimated.

The endpoint is defined as the end-of-study measurement minus the baseline measurement. This direction matters when interpreting signs: the registry states that a negative value represents a decrease in intermuscular fat deposition. This definition makes the result a change score rather than an endpoint value alone. In a repeated-measures study, a change score reflects the difference between two measurements from the same participant, if both measurements are available. It does not automatically control for changes that would also have occurred without the intervention.

As general statistical context, a confidence interval communicates uncertainty around an estimated quantity under the assumptions of the method used to calculate it. A narrower interval indicates greater precision than a wider interval, but interval width depends on factors such as variability and the amount of usable data. No confidence interval for the primary endpoint is reported in the registry record. Nor is a hypothesis test or p-value reported, so no inferential conclusion can be drawn from the posted record.

What does the sequential structure mean?

The registry identifies a sequential model, with a run-in period, dulaglutide treatment, and follow-up. MRI assessments were described for several points across these phases. This arrangement can support tracking measurements over time in the study participants. It is distinct from a randomized parallel-group comparison: allocation is recorded as NA, masking as none, and the registry identifies that there was no randomized comparison. Any before-and-after contrast would therefore be an observation over time, not a randomized estimate of the difference between treatment and control.

As general statistical context, a repeated-measures analysis can account for the fact that observations from one participant are related to each other. The particular model matters because it determines how within-participant correlation, incomplete observations, and timing are handled. The statistical model used for the endpoint is not reported in the registry record. It is also not reported whether the primary analysis used only the baseline and end-of-study values, all scheduled MRI observations, or another approach.

How should a planning illustration be read?

Any sample-size figures associated with the posted results are planning illustrations rather than observed power or evidence that the study had a particular chance of detecting an effect. The stated assumptions for those illustrations are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They use a fraction of the observed effect as the effect to detect. The record describes these calculations as planning illustrations computed from the observed effect, not as the trial’s own design.

Those assumptions do not describe the actual sequential study as a randomized two-arm trial. In particular, the record does not describe equal allocation between two randomized arms. The planning figures therefore should not be treated as a retrospective assessment of whether the study was adequately powered, and they do not replace the missing endpoint estimate and uncertainty. The trial’s own sample-size justification is not reported in the registry record.

Why does over-dispersion matter in general?

Over-dispersion is a general issue in statistical models for count outcomes. It occurs when observed variation is greater than the model assumes. If ignored, estimated uncertainty may be too small and statistical tests may be poorly calibrated. The primary endpoint in this study is continuous, not a count, so over-dispersion is not an explanation for its missing result. The registry does not identify an over-dispersion analysis, and no such method should be inferred.

More broadly, the registry record reports zero analyses and does not provide the statistical analysis plan. The chosen estimand, handling of missing measurements, assumptions about distributions, covariate adjustments, and any sensitivity analyses are not reported in the registry record. General concepts can explain how such choices affect interpretation, but they cannot identify what was done in this study. In the absence of the analysis details and numerical results, the endpoint’s observed magnitude and uncertainty remain unknown.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Dulagutide Arm")
n   <- c(7)
m   <- c(-0.009)
sp  <- c(0.0526)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Dulagutide Arm  7  -0.009  0.053  -0.058  0.040

11. Multiplicity, Missing Data and Analysis Populations

The study description identifies four specific aims and the registry lists four outcome measures. When multiple outcomes or analyses are considered, there is a general statistical issue called multiplicity: with more opportunities to test a hypothesis, the chance of at least one apparently notable result can increase. Prespecified priorities and suitable adjustment or interpretation strategies can help readers understand this issue. The registry record does not report a multiplicity strategy, a hierarchy of confirmatory outcomes, or an analysis plan. It is therefore not possible to determine whether or how multiplicity was addressed.

The registry records zero analyses. This means inferential results and analytical details are not posted in the record; it does not establish that no analyses were conducted outside the registry. The results of the listed outcome measures, aside from the safety counts, are not reported in the registry record. The primary endpoint’s numerical estimate and uncertainty are also not reported.

Missing-data methods and the number of participants contributing to each endpoint are not reported in the registry record. The enrollment count is seven, but that alone does not indicate how many completed each MRI assessment or were included in an analysis. As general statistical context, incomplete repeated measurements can change the analyzed group and can affect estimates, especially if missingness is related to participant characteristics or outcomes. The method used to address missing measurements, if any, is not reported in the registry record.

The analysis population is also not described. It is not reported whether the analysis included all enrolled participants, only participants who started treatment, only those completing the protocol, or another population. No protocol-deviation summary or sensitivity analysis is reported. These omissions limit assessment of how representative any analyzed group would be, even if an endpoint estimate were available.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry reports safety figures separately for the run-in period, dulaglutide arm, and follow-up. Seven participants are listed as at risk in each period. The serious adverse event count is zero in each of the three periods, and deaths are also recorded as zero in each period. The dulaglutide period lists two other adverse events; the run-in and follow-up periods list zero other adverse events.

These are descriptive registry counts. They do not show that the risk of an event was zero, nor do they establish that treatment caused or prevented an event. With seven participants at risk in each period, the counts describe what the registry recorded for this small study, not a precise estimate of event frequency in a wider population. Because the study is sequential rather than a randomized comparison, period-specific counts should not be read as a controlled comparison between groups.

The registry does not report the terms for the two other adverse events, their severity, timing, duration, or relationship to dulaglutide. The serious adverse event terms list is empty. No further event-level detail is reported in the registry record. The figures therefore allow a limited description of posted counts, but not a detailed safety profile or comparative risk assessment.

13. What the Result Does, and Does Not, Mean

The record identifies a pilot and feasibility study examining dulaglutide and ectopic fat deposition in CKD, with MRI-assessed change in an intermuscular fat-to-muscle ratio as the primary endpoint. It describes the intervention schedule, the sequential measurement periods, and the direction of the change score. It also reports enrollment of seven participants and limited adverse-event counts.

It does not report the numerical result for the primary endpoint. Without the mean change and a measure of its variability or uncertainty, the record cannot establish whether the measured ratio increased, decreased, or remained similar on average. The endpoint definition says that a negative value would indicate a decrease; it does not report that such a value was observed. No statistical significance or precision can be inferred when the estimate, interval, and test result are absent.

The sequential design does not provide a randomized control group. As general statistical context, within-participant measurements can describe change over time, but they cannot alone distinguish an intervention-related change from other influences that occur over the same period. The registry does not report an adjusted analysis that would address this limitation. Consequently, the design and posted results do not support a causal comparison between dulaglutide and an untreated or alternative-treatment group.

The study’s stated aims also include mitochondrial function, physical performance, and safety and feasibility. Numerical results for these outcomes are not reported in the registry record. The safety counts show no serious adverse events recorded in the listed periods and two other adverse events during the dulaglutide period, but the event terms and further details are absent. These data should be read as a limited description of the registry entries, not as evidence of comparative safety.

The study can be understood as a small pilot addressing measurement and feasibility questions in a specific CKD population. Its posted record does not provide the outcome analyses needed to assess the size, direction, or precision of the primary change, or to draw treatment-effect conclusions.

14. Why This Trial Matters Statistically

This study is statistically notable because its main question concerns a continuous imaging measure observed at multiple time points in a small, sequential study. The registry’s endpoint definition is explicit about the measurement region, ratio, and direction of change. That clarity helps readers understand what a reported value would mean and prevents confusing a negative change with an increase. Yet interpretation still depends on the numerical estimate and its uncertainty, neither of which is reported in the registry record.

The design also illustrates an important distinction between measuring change and estimating a treatment effect. Repeated measurements can show how an outcome varies across study phases among participants. A randomized comparison is designed to support a different inference: comparing outcomes between groups assigned to different conditions. This record describes no randomized comparison, so a change across the treatment period cannot by itself establish what caused that change.

The seven-participant enrollment and pilot-and-feasibility framing are relevant to how much can be learned from the record. A pilot can address practical questions and generate information for future work, but any estimate from a small group may be uncertain. The statistical precision cannot be evaluated in this case because the endpoint result and its dispersion or confidence interval are not posted. A planning illustration based on an observed effect should not be mistaken for observed power or for evidence that an effect was established.

Finally, the record includes multiple aims and outcomes while reporting zero analyses. This makes transparent reporting of outcome estimates, analysis populations, missing data, and multiplicity methods especially important for readers trying to interpret the study. Those details are not reported in the registry record. The study therefore demonstrates why a well-defined endpoint and a completed study status are not substitutes for posted numerical results and methods.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The most consequential limitation for interpreting the posted record is that it does not report the primary endpoint result. The mean change, standard deviation, confidence interval, and test result are absent, as are numerical findings for the other listed outcomes. The record therefore cannot describe the observed magnitude or precision of change in MRI-assessed intermuscular fat.

The study enrolled seven participants and was designed as a pilot and feasibility study. This small enrollment limits how broadly findings could be generalized even if complete estimates were available. The registry describes stage 3–4 CKD as the intended population, but further participant characteristics and detailed eligibility criteria are not reported in the registry record. The primary outcome population field is blank.

The sequential design has no randomized control group, and masking is recorded as none. These features limit causal interpretation and may leave outcome assessment open to influences beyond the intervention. The MRI schedule includes assessments across run-in, treatment, and follow-up, but participant-level completion and adherence information are not reported. The statistical analysis plan, analysis population, handling of missing measurements, and sensitivity analyses are also not reported in the registry record.

The record lists four outcome measures and zero analyses, without a reported multiplicity strategy. It is therefore not possible to establish which outcome analyses were prespecified or how findings across outcomes should be interpreted together. Safety reporting is also limited: the record includes period-specific counts but does not provide terms for the two other adverse events, event-level details, or relatedness assessments.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Effects of GLP1-RA on Ectopic Fat Deposition in Chronic Kidney Disease — NCT05254418.
• Registry record last updated 2025-04-20; status last verified 2025-04.
• Results first posted 2025-04-20.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

NCT05254418 is a completed phase 2 pilot and feasibility study sponsored by Vanderbilt University Medical Center. The record describes seven participants with stage 3–4 CKD and a sequential, non-randomized design without masking. Participants received dulaglutide injections at 1.5 mg per week for 12 weeks, alongside standard care.

The primary endpoint was change in the MRI-derived mid-thigh intermuscular fat-to-muscle volume ratio, defined as end of study minus baseline over a 16-week timeframe. A negative value would indicate a decrease. The record lists four outcome measures and zero analyses, but does not report the primary endpoint result, an analysis, or numerical results for the other outcomes.

For safety, zero serious adverse events and zero deaths are listed in each of the run-in, treatment, and follow-up periods. Two other adverse events are listed during the dulaglutide period; event terms and further details are not reported in the registry record.