This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for An Examination of the Blood Pressure Lowering Ability and Safety of Olmesartan Medoxomil in Elderly Patients With Hypertension (NCT00412932), a non-randomized phase 4 study. The primary outcome is Change From Baseline in Mean 24-hour Ambulatory Systolic Blood Pressure After 12 Weeks of Active Treatment.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00412932 |
| Phase | Phase 4 |
| Condition | Hypertension |
| Allocation | Non-Randomized |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 178 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Daiichi Sankyo |
| Results posted | Yes |
2. Clinical Question
Population
Participants 65 years of age or older with hypertension. The registry record states that 178 participants started the active treatment period. The endpoint population required baseline and week 12 ambulatory blood pressure measurements.
Intervention
An olmesartan medoxomil-based treatment regimen. Participants started with olmesartan medoxomil 20 mg, with protocol-described titration to higher doses and combinations with hydrochlorothiazide if blood pressure was not controlled.
Comparator
There was no separate control group. The study was single-arm, non-randomized, and unmasked, so the primary question is not a comparison between randomized treatments.
Primary question
What was the change from baseline in mean 24-hour ambulatory systolic blood pressure after 12 weeks of active treatment among participants with the required baseline and week 12 measurements?
The primary outcome was a continuous measurement reported in mm Hg. It focused on change within the treatment group rather than a difference between treatment groups. Because participants could be titrated through different olmesartan medoxomil and hydrochlorothiazide regimens, the question concerns the treatment strategy as described in the record, not one fixed dose alone.
The registry record describes a 14 week study in people 65 years of age or older with high blood pressure, while the primary endpoint timeframe is baseline to 12 weeks of active treatment. It also lists secondary ambulatory blood pressure outcomes, including diastolic measurements, daytime and nighttime measurements, and counts meeting stated blood pressure thresholds. The results for these outcomes are not reported in the registry record.
3. Trial Design
This was a Phase 4, prospective, open-label, single-arm study sponsored by Daiichi Sankyo. Its official title describes an olmesartan medoxomil-based treatment regimen in elderly participants with hypertension. The allocation was non-randomized, masking was absent, and the study model was a single group. There was no concurrent control arm described in the registry record.
The record states that 178 participants started the active treatment period and that 23 dropped out. The ambulatory blood pressure monitoring subset was defined as participants who received at least one dose of active study medication and had both baseline and week 12 ambulatory blood pressure monitoring. That subset is reported as 150 participants. These counts describe different aspects of enrollment and outcome eligibility; the registry record does not explain the difference between the counts.
All participants started with olmesartan medoxomil 20 mg. If blood pressure was not controlled, the treatment description says participants were titrated at 3-week intervals to olmesartan medoxomil 40 mg, then, if needed, olmesartan medoxomil 40 mg plus hydrochlorothiazide 12.5 mg, and then, if needed, olmesartan medoxomil 40 mg plus hydrochlorothiazide 25 mg. The primary outcome included participants at the end of the 12-week treatment period regardless of whether they were titrated, provided they had both required ambulatory measurements.
The brief description calls the study a 14 week study, and the primary endpoint is assessed after 12 weeks of active treatment. The registry record lists the study status as completed. Details about the recruitment process, eligibility criteria beyond age and hypertension, adherence, and the reasons for individual dose changes are not reported in the registry record. Since there was no randomized control group, the design does not isolate the treatment regimen’s effect from changes that might occur over time or from other influences.
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.
Before assignment: After 3-4 weeks of placebo, patients with a systolic pressure (SBP) ≥150 ≤199mmHg and diastolic pressure (DBP) ≤109 mmHg at the last 2 visits, and 8-hr daytime SBP \>140 and ≤199 mmHg and DBP ≤109 mmHg by ambulatory blood pressure monitoring were entered.All started with Olmesartan 20 mg and were titrated if their blood pressure was not controlled
Olmesartan (Olm) 20 mg
| Stage | Active Treatment Period |
|---|---|
| STARTED | 178 |
| COMPLETED | 171 |
| NOT COMPLETED | 7 |
Reasons for not completing this period:
| Reason | Active Treatment Period |
|---|---|
| Adverse Event | 1 |
| Lack of Efficacy | 2 |
| Protocol Violation | 1 |
| Withdrawal by Subject | 2 |
| Other | 1 |
Olmesartan 40 mg
| Stage | Active Treatment Period |
|---|---|
| STARTED | 169 |
| COMPLETED | 161 |
| NOT COMPLETED | 8 |
Reasons for not completing this period:
| Reason | Active Treatment Period |
|---|---|
| Adverse Event | 4 |
| Lack of Efficacy | 3 |
| Withdrawal by Subject | 1 |
Olm+Hydrochlorothiazide 12.5 mg
| Stage | Active Treatment Period |
|---|---|
| STARTED | 159 |
| COMPLETED | 153 |
| NOT COMPLETED | 6 |
Reasons for not completing this period:
| Reason | Active Treatment Period |
|---|---|
| Adverse Event | 3 |
| Withdrawal by Subject | 3 |
Olm+ Hydrochlorothiazide 25 mg
| Stage | Active Treatment Period |
|---|---|
| STARTED | 125 |
| COMPLETED | 123 |
| NOT COMPLETED | 2 |
Reasons for not completing this period:
| Reason | Active Treatment Period |
|---|---|
| Adverse Event | 1 |
| Lost to Follow-up | 1 |
Analysis population for the primary outcome, as defined in the registry: 178 participants started the active treatment period. 23 dropped out. 150=The ambulatory blood pressure monitoring (ABPM) subset was defined as subjects who received at least one dose of active study medication and had a baseline and week 12 ABPM.
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.
| Characteristic | Unit | Active Treatment Period |
|---|---|---|
| Participants analysed | 178 | |
| Age Continuous | years | 72.0 (SD 5.3) |
| Sex: Female, Male: Female | Participants | 85 |
| Sex: Female, Male: Male | Participants | 93 |
| Region of Enrollment: United States | participants | 178 |
| Baseline stage of hypertension: Stage 1 hypertension | participants | 62 |
| Baseline stage of hypertension: Stage 2 hypertension | participants | 116 |
| Baseline 24-hour ambulatory diastolic blood pressure | mm Hg | 80.7 (SD 8.5) |
| Baseline 24-hour ambulatory systolic blood pressure | mm Hg | 149.1 (SD 11.2) |
| Baseline diastolic blood pressure | mm Hg | 87.7 (SD 9.6) |
| Baseline heart rate | beats/minute | 71.5 (SD 11.4) |
| Baseline systolic blood pressure | mm Hg | 165.5 (SD 11.9) |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in Mean 24-hour Ambulatory Systolic Blood Pressure After 12 Weeks of Active Treatment, measured over baseline to 12 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Error |
| Unit | mm Hg |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change from baseline in mean 24-hour ambulatory systolic blood pressure after 12 weeks of active treatment, measured in mm Hg. Ambulatory blood pressure monitoring records blood pressure across the day and night in a person’s usual setting. A mean over 24 hours is intended to represent blood pressure across that monitoring period, rather than relying on a single clinic measurement.
Change from baseline expresses how the measured value at follow-up differs from the participant’s starting value. This can describe the direction and size of change within the treated group, while accounting descriptively for where participants began. The registry record specifies a mean as the endpoint summary and standard error as the dispersion measure. A standard error describes the precision of an estimated mean, rather than the spread of individual participants’ measurements.
The endpoint requires both baseline and week 12 ambulatory measurements. This paired-measurement requirement means participants without either measurement cannot contribute to the defined endpoint population. The record identifies 150 participants in the ambulatory monitoring subset. It does not report the estimated mean change, its standard error, or a confidence interval in the registry record for this analysis, so the size and precision of the endpoint result cannot be described.
The endpoint is useful for describing a physiological measurement over a specified treatment period. It is not, by itself, a randomized estimate of what would have happened without treatment. In a single-arm, open-label study, the observed within-group change can also reflect factors other than the treatment strategy.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The primary endpoint is clearly specified as change in mean 24-hour ambulatory systolic blood pressure from baseline to 12 weeks. However, the numerical result for this outcome is not reported in the registry record. No mean change, standard error, confidence interval, or statistical test result is available in the record details. Consequently, the magnitude, direction, and precision of the observed change cannot be assessed.
The study’s design is also important to interpretation. It had one treatment group, no random allocation, and no masking. A change over time among participants in that group can describe what happened during the treatment period, but it cannot establish how the same participants would have changed in the absence of the treatment regimen. Without a control group, the observed change cannot be separated from possible influences such as natural variation, changes in measurement conditions, or other time-related factors. These are general considerations for interpreting single-arm studies, not reported events in this study.
The treatment regimen allowed titration if blood pressure was not controlled. Therefore, the study question is about an olmesartan medoxomil-based regimen that could include hydrochlorothiazide, rather than a single unchanged dose for every participant. The registry record says the primary endpoint included participants regardless of whether they were titrated, as long as they had baseline and week 12 ambulatory measurements. It does not report how many participants received each regimen or how outcomes varied by titration.
Eligibility for the ambulatory endpoint required measurements at both time points. The record identifies 150 participants in this subset, states that 178 started active treatment, and reports 23 dropouts. It does not explain the relationship among these counts or report the endpoint-specific reasons for missing measurements. If inclusion in an analysis depends on having complete measurements, the analyzed group may differ from those without measurements; whether that occurred in a way that affected results cannot be determined from the registry record.
The record lists secondary outcomes involving 24-hour diastolic pressure, daytime and nighttime systolic and diastolic pressure, and attainment of specified ambulatory thresholds. Their numerical results are not reported in the registry record. The record also gives the number of outcome measures and analyses, but does not identify a multiplicity procedure or explain which analyses were conducted. No conclusion about statistical significance, clinical importance, or consistency across outcomes is warranted without the estimates and their uncertainty.
In general, a confidence interval would communicate a range of values compatible with the data under the analysis assumptions, and a standard error would communicate the estimated precision of a mean. Neither can be interpreted for this endpoint without its reported estimate and uncertainty. A p-value, even if available, would not substitute for the size of the change or its precision. Since the result itself is absent, the statistical interpretation must remain focused on the design, endpoint definition, and limits of what the registry record reports.
9. Statistical Methods Explained
The primary outcome is a continuous variable: change in mean 24-hour ambulatory systolic blood pressure, expressed in mm Hg. The registry record identifies the summary as a mean and the dispersion as a standard error. It does not report the endpoint estimate or a full statistical analysis plan, so the explanations below describe general statistical concepts rather than methods confirmed as having been used in this study.
What does a mean change represent?
For a participant with measurements at baseline and week 12, change is defined by comparing the follow-up measurement with the baseline measurement. A group mean change summarizes those individual changes. It describes the average within-person movement in the analyzed group, but does not show how much participants differed from one another. Some participants could have changes unlike the group average. Individual-level data or additional summaries would be needed to describe that variation.
Using change from baseline can make the question directly about movement over the treatment period. It does not automatically remove bias or establish that the treatment caused the change. In a single-arm study, the mean change has no concurrent untreated or alternative-treatment group as a reference. General influences over time and measurement variability remain possible explanations alongside any treatment-related contribution.
What does the standard error describe?
In general, the standard error measures the precision of an estimated mean. It is not the same as the standard deviation, which describes variation among individual observations. A smaller standard error generally indicates a more precisely estimated group mean under the analysis assumptions, but precision does not determine whether an estimate is clinically important or causally attributable to treatment.
A confidence interval is a commonly used way to express uncertainty around an estimate. In general, it gives a range generated by a statistical procedure that has a stated long-run coverage property when its assumptions hold. It does not guarantee that the true value lies in that particular interval, and its interpretation depends on the study design and analysis. The registry record does not report a confidence interval for the primary endpoint, nor does it report enough endpoint statistics to reconstruct one without making additional calculations.
Why does the analysis population matter?
The endpoint definition requires both baseline and week 12 ambulatory measurements. The registry record defines the ambulatory monitoring subset as participants who received at least one dose of active study medication and had those two measurements, and reports 150 participants in that subset. A complete-measurement analysis uses information from participants with the required observations. If participants without follow-up measurements differ from those with them, the analyzed mean may not represent the experience of all who started treatment. This is a general risk to consider; the registry record does not describe the missing-data pattern or its consequences.
The record states that 178 participants started active treatment and 23 dropped out, but does not provide an account of the endpoint analysis beyond the subset definition. It does not say whether missing values were imputed, whether any alternative analysis populations were used, or whether sensitivity analyses assessed the impact of missing data. Those details are not reported in the registry record.
What can a single-arm estimate establish?
A within-group estimate describes the average change observed among participants meeting the endpoint requirements. It does not estimate a between-group treatment contrast, because the design has no separate comparator group. In general, randomization helps balance measured and unmeasured factors between groups, while a concurrent comparator helps distinguish treatment-period changes from background changes. Neither feature is present in this study’s design as described in the registry record. The observed change, if reported, would therefore need to be interpreted as a descriptive result for the study group and regimen, not as a controlled causal effect.
The open-label design means participants and study personnel were not masked. For a measured physiological endpoint, the measurement process and protocol are relevant to judging potential bias. The registry record does not describe the measurement procedures in enough detail to assess them. Ambulatory monitoring provides measurements over a 24-hour period, but that feature alone does not remove all possible measurement or selection concerns.
How should titration be understood?
The treatment description permits dose escalation and addition of hydrochlorothiazide when blood pressure was not controlled. The primary endpoint included participants regardless of titration. Thus, in general terms, the endpoint pertains to an adaptive treatment strategy rather than the isolated effect of one fixed dose. The record does not report treatment exposure by dose, the proportion titrated, or analyses separating outcomes by regimen. A comparison among titration levels would also need to account for the fact that titration was linked to blood pressure control, rather than randomly assigned.
What can planning illustrations tell readers?
In general, a sample-size calculation uses assumptions about the effect to be detected, variability, significance level, power, and allocation. Such calculations are planning exercises, not evidence about the result observed in a completed study. Sample sizes calculated using the observed effect are retrospective illustrations and should not be described as observed power. The registry record does not report the trial’s own sample-size justification or detailed design assumptions. Any sample-size illustrations associated with the analysis are not evidence that the trial was planned to detect those effects, and they cannot substitute for the unreported endpoint estimate and uncertainty.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists seven outcome measures and four analyses. It names the primary endpoint and lists secondary outcomes concerning ambulatory diastolic pressure, daytime and nighttime blood pressure, and achievement of specified thresholds. It does not report which four analyses were conducted, how the analyses map to the listed outcomes, or whether a multiplicity adjustment was used. The approach to controlling the chance of false-positive findings across multiple tests is therefore not reported in the registry record.
The primary endpoint requires baseline and week 12 ambulatory blood pressure measurements. The record defines a subset of 150 participants using that requirement and states that 178 participants started active treatment, with 23 dropouts. The reasons for dropout, the number missing each measurement, and the handling of missing outcomes are not reported in the registry record. It does not describe imputation, a model using incomplete measurements, or sensitivity analyses for missing data.
These omissions limit the assessment of how representative the analyzed participants were of those who started treatment and how robust any estimate would be to missing observations. In general, complete-case results can be affected if having measurements is related to the outcome. The available record details do not establish whether such a relationship occurred. Details of the analysis population for secondary outcomes are also not reported in the registry record.
11. What the Result Does, and Does Not, Mean
The registry record defines a relevant statistical question: the average change in mean 24-hour ambulatory systolic blood pressure from baseline to 12 weeks in participants receiving an olmesartan medoxomil-based regimen. It also describes the treatment options and the requirement for baseline and follow-up measurements. But the numerical result for the primary endpoint is not reported in the registry record. The observed change and its precision therefore cannot be stated.
Even if a within-group change were available, this study’s single-arm, non-randomized design would not provide a direct comparison with an untreated group or another treatment group. A measured change during the study period would describe the participants’ experience, but would not on its own establish what caused the change. This distinction is central when interpreting studies without a concurrent comparator.
The regimen could be titrated, including the addition of hydrochlorothiazide, and the primary endpoint included participants regardless of titration. The study therefore concerns a treatment strategy with possible adjustments. The record does not report how many participants followed each dose pathway or give separate results by regimen. It cannot establish an effect attributable to one particular dose in the registry record reported.
The study also specified secondary ambulatory outcomes, but their results are not reported in the registry record. The record does not report an analysis plan for multiple outcomes or the handling of missing measurements. These gaps prevent a fuller assessment of consistency across endpoints and sensitivity to missing data. No claim about treatment benefit, lack of benefit, safety findings, or clinical importance follows from the endpoint description alone. The record’s statement that the medication had been approved for high blood pressure is part of the study description, not a result of this study.
12. Why This Trial Matters Statistically
This trial is statistically informative as an example of the distinction between a within-group change and a controlled treatment comparison. The primary outcome is defined as a change from baseline, but the study has one group and no random allocation. Those design features determine what an estimate could mean, independently of whether the outcome is clinically familiar or measured over an extended period.
The study also illustrates how outcome eligibility can depend on measurement completion. The registry record reports 178 participants starting treatment, 23 dropouts, and an ambulatory monitoring subset of 150 participants defined by receipt of active medication and measurements at baseline and week 12. Without further detail on missing observations and analysis methods, readers cannot fully assess how the analyzed group relates to everyone who started treatment.
Titration adds another interpretive feature. The primary outcome includes participants regardless of whether their regimen was adjusted, so the endpoint addresses an olmesartan medoxomil-based treatment strategy rather than a single fixed dose. The record does not report how participants were distributed across those possible regimens or provide dose-specific outcome estimates.
Finally, the registry record specifies a primary endpoint and several secondary outcomes but does not report numerical results or a multiplicity approach. This makes it important to distinguish a well-defined measurement question from evidence about the measured result. Statistical interpretation depends not only on the endpoint label, but also on the estimate, uncertainty, analysis population, missing-data handling, and design. Several of those elements are not reported in the registry record.
13. 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 key limitation for interpreting the primary endpoint is that its numerical result is not reported in the registry record. Without the estimated mean change and its uncertainty, the direction, magnitude, and precision of the result cannot be assessed. The registry record also does not report the individual measurements or the distribution of participant-level changes.
The study was single-arm, non-randomized, and open-label. There was no concurrent control group, so an observed within-group change cannot be separated from other changes over time using a randomized treatment contrast. The design does not support a direct comparison with another treatment or with no treatment.
The endpoint population required baseline and week 12 ambulatory measurements. Although the record identifies 150 participants in that subset, it does not explain the relationship between this count, the 178 participants who started active treatment, and the 23 dropouts. Reasons for missing measurements, missing-data methods, and sensitivity analyses are not reported in the registry record.
The treatment could be titrated and could include hydrochlorothiazide. The record does not report how many participants received each regimen, the extent of adherence, or outcome results by regimen. The study therefore does not provide a reported basis for distinguishing outcomes associated with particular doses or combinations.
Additional limitations include the absence of reported numerical results for the secondary outcomes and the lack of a reported multiplicity approach. The registry record does not report the trial’s sample-size justification, a detailed statistical analysis plan, or the procedures used for ambulatory measurement. These unreported details limit evaluation of precision, selective analysis, and measurement quality.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: An Examination of the Blood Pressure Lowering Ability and Safety of Olmesartan Medoxomil in Elderly Patients With Hypertension — NCT00412932.
- Registry record last updated 2009-09-22; status last verified 2009-09.
- Results first posted 2009-09-11.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
17. Record Summary
NCT00412932 is a completed Phase 4, prospective, open-label, single-arm study sponsored by Daiichi Sankyo. It examined an olmesartan medoxomil-based regimen in participants 65 years of age or older with hypertension. The registry record states that 178 participants started active treatment and describes titration options that could include hydrochlorothiazide.
The primary endpoint was change from baseline in mean 24-hour ambulatory systolic blood pressure after 12 weeks of active treatment, in mm Hg. The endpoint required baseline and week 12 ambulatory measurements; the record identifies 150 participants in the ambulatory monitoring subset and reports 23 dropouts. The numerical primary endpoint result, its uncertainty, secondary outcome results, missing-data methods, and multiplicity approach are not reported in the registry record.
Because the study had one group and no random allocation, its design does not provide a controlled comparison. The record describes the question and population, but not enough numerical outcome information to assess the observed change or its precision.