Blopress Tablets Specified Drug-use Survey "Hypertension: Survey on Patients With Metabolic Syndrome": Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Blopress Tablets Specified Drug-use Survey "Hypertension: Survey on Patients With Metabolic Syndrome" (NCT02166697), a registered phase not stated study. The primary outcome is Number of Participants Reporting One or More Adverse Drug Reactions (ADR).

2. Clinical Question

These aims address different questions. The primary outcome is a treatment-safety measure based on investigators' judgments about causality. The exploratory event outcomes concern the occurrence of cerebrovascular or cardiovascular events and their relationship to underlying risk factors. The registry record does not report a numerical result for the primary outcome in the registry record for this analysis, so the outcome's magnitude cannot be described from the record summary. Nor can the exploratory relationships be interpreted as causal effects of risk factors or treatment.

3. Trial Design

This is a completed specified drug-use survey sponsored by Takeda, rather than a randomized comparison. The registry identifies hypertension as the condition and candesartan cilexetil as the drug under study. Its stated purpose was to investigate treatment status among hypertensive patients with metabolic-syndrome-related risk factors and to explore relationships between risk factors, such as visceral fat accumulation, and cerebrovascular or cardiovascular events.

The recorded enrollment is 14151. The primary outcome describes a safety analysis set comprising participants who were enrolled and completed the study. The adverse-event record separately gives an at-risk count of 13804 for candesartan cilexetil. These figures refer to different descriptions in the record and should not be assumed to be interchangeable. The registry record does not explain the difference between them.

The intervention description is oral candesartan cilexetil at 4-8 mg once daily, increased up to 12 mg as necessary. The study period is recorded as starting in 2006-06, with primary completion in 2010-11, and the status is COMPLETED. The primary outcome timeframe is baseline up to 3 years.

There is no stated allocation method, and the record explicitly cautions that the arms are not a like-for-like control comparison. Consequently, treatment-group observations are descriptive rather than evidence from a randomized contrast. The registry record does not report the recruitment process, detailed follow-up procedures, protocol deviations, or a statistical analysis plan. Those omissions limit what can be reconstructed about how participants were observed and how results were analyzed.

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: Participants with a historical diagnosis of hypertension with metabolic syndrome-related risk factors were observed in a single treatment group to receive candesartan cilexetil 4 milligrams (mg).

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The safety analysis set was defined as all participants who were enrolled and completed the study.

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.

Population: The safety analysis set included all participants who were enrolled and completed the study.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants Reporting One or More Adverse Drug Reactions (ADR), measured over Baseline up to 3 years.

The primary endpoint is the number of participants reporting one or more adverse drug reactions from baseline up to 3 years. The record defines an adverse drug reaction as an adverse event that, in the investigator's opinion, has a causal relationship to study treatment. Adverse events are described as unfavorable and unintended signs, symptoms, or diseases temporally associated with use of a medicinal product, reported from the first dose through the last dose.

This kind of endpoint is used to describe how often treatment-associated adverse reactions are reported in the defined safety population. Counting participants with at least one reaction focuses on whether a participant experienced an event, rather than on the total number of events they experienced. It is therefore a participant-level summary, not necessarily a measure of event severity, duration, or recurrence.

As a general statistical point, an endpoint based on investigator-assessed causality depends on both the occurrence of events and the assessment that they are related to treatment. The registry record does not report the primary endpoint's numerical result in the registry record. The separate serious and other adverse-event figures should not be substituted for this endpoint: they are not identified as the number of participants with one or more investigator-attributed adverse drug reactions.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Interpretation starts with identifying what is counted. The primary outcome is a participant count: people reporting one or more adverse drug reactions. It is not a count of every adverse event, and it is not an event rate per unit of follow-up time. The registry defines adverse drug reactions through an investigator's opinion about a causal relationship to treatment. The separate serious and other adverse-event figures have different labels and should not be treated as equivalent to the primary endpoint.

What does a participant count tell us?

As a general statistical explanation, a participant count records whether each person met an outcome definition during observation. It can be useful for describing the share of an observed population experiencing an event, but that interpretation depends on having a clearly defined denominator and complete outcome ascertainment. A participant who experiences multiple events may still contribute only once to a measure defined as one or more events. Conversely, a total event count could include repeated events in the same participant. The registry's primary endpoint is framed as a participant count, while the separate adverse-event figures are listed as affected participants.

For the primary outcome, the population is described as participants who were enrolled and completed the study. The serious and other event information lists 13804 at risk. The record summary also gives an enrollment of 14151. These entries use different population descriptions; they should not be combined or treated as the same analysis population without further information. The record does not report details of how the analysis population was formed beyond the stated definition.

Why does the comparison design matter?

As a general principle, randomization can make treatment groups comparable with respect to measured and unmeasured baseline characteristics, on average, when implemented appropriately. This record is not a randomized comparison, and allocation is not stated. The registry also warns that its arms are not a like-for-like control comparison. Thus, any contrast involving these data would not have the same interpretation as a randomized treatment-versus-control estimate. Differences could reflect participant characteristics, clinical decisions, follow-up, or other factors, as well as treatment.

The description of a single drug-use survey also means that the figures primarily characterize observed experience under the recorded treatment conditions. They do not, on their own, estimate what would have happened to the same participants under a different treatment or no treatment. General causal-inference reasoning requires a credible comparison to distinguish treatment effects from other explanations. Such a comparison is not established in the registry record.

What is the role of uncertainty?

As a general explanation, a confidence interval describes a range of values compatible with the observed data under a specified statistical model and procedure. Its width reflects statistical precision: wider intervals indicate greater uncertainty about the underlying quantity. A point estimate without an interval can give an incomplete impression of how much the data constrain the true value. The registry entries available for this analysis do not include confidence intervals or a numerical primary endpoint result, so precision for that endpoint cannot be evaluated.

For event outcomes, follow-up duration and completeness matter. A simple participant count does not account for differing time at risk unless the analysis is designed to do so. The primary outcome has a timeframe of baseline up to 3 years, but detailed individual follow-up and censoring information are not reported in the registry record. The summary therefore cannot establish whether all participants had comparable observation time.

How should planning illustrations be understood?

The planning illustration described for this material is based on a hypothetical two-arm calculation using equal allocation, a two-sided significance level of 0.05, and a normal approximation. It uses a stated fraction of an observed effect as the effect to detect. Such calculations are planning illustrations, not observed results and not observed power. The record does not identify them as the trial's original design assumptions. Because this survey is not a randomized like-for-like comparison, the hypothetical two-arm assumptions should not be mistaken for the actual design.

In general, sample-size calculations depend on the outcome, the effect considered important, variability or event frequency, allocation, and the statistical procedure. If those assumptions do not match the design or endpoint, the resulting planning quantity may not be relevant to the study's actual ability to estimate an outcome. Over-dispersion, when data vary more than an assumed model allows, can also make uncertainty larger than a simple model suggests. The registry record does not report whether over-dispersion was assessed, nor does it report a study-specific sample-size justification.

The record lists six outcome measures and no analysis entries. That absence does not establish that no analyses were performed outside the registry; it means an inferential analysis plan and its implementation are not reported in the registry record. Statistical significance, adjustment methods, and model specifications therefore cannot be inferred from these registry entries.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Candesartan Cilexetil")
n      <- c(13804)
events <- c(230)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Candesartan Cilexetil  13804  230  1.7  1.5  1.9  1.5  1.9  1.5  1.9

11. Multiplicity, Missing Data and Analysis Populations

The registry lists six outcome measures, including the primary safety endpoint and secondary cerebrovascular or cardiovascular event outcomes. When several outcomes or subgroup relationships are examined, the chance of at least one apparently unusual result can increase. As a general statistical principle, multiplicity procedures can control error rates across a family of tests, but their use depends on which outcomes were planned together and what inferential claims are intended.

The registry record does not report a multiplicity strategy, a hierarchy among secondary outcomes, or which analyses were prespecified. It also does not report an inferential analysis plan. The exploratory framing of the risk-factor relationships is important: findings from exploratory analyses should not automatically be treated as confirmatory evidence, particularly when many risk-factor combinations are considered.

Missing-data methods are not reported in the registry record. The primary safety population is defined as participants enrolled and completing the study, but the record summary does not describe participants who did not complete, their outcome status, or how missing observations were handled. This definition could restrict the primary safety analysis to completers; the registry entries do not show whether that affected the observed results. It is also not reported whether event ascertainment was complete throughout each participant's follow-up.

The registry record gives an enrollment figure and a separate at-risk count for the listed adverse-event results. It does not provide a full accounting that reconciles those populations. The numbers should therefore be interpreted according to their stated descriptions rather than merged into a single denominator. Without further detail, the impact of missing follow-up or population exclusions cannot be assessed.

12. Safety Results

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

Other (non-serious) adverse events

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

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: cerebral infarction (0.4%), angina pectoris (0.4%), acute myocardial infarction (0.2%), cerebral haemorrhage (0.1%), renal failure (0.1%).

The posted safety information lists 13804 at risk in the candesartan cilexetil group, with 320 affected for serious adverse events and 230 affected for other adverse events. These are separate serious and other adverse-event figures, not a direct substitute for the primary endpoint of participants reporting one or more adverse drug reactions. The primary endpoint requires an investigator judgment that an event was causally related to treatment.

The record also lists serious-event terms and percentages: cerebral infarction and angina pectoris at 0.4% each; acute myocardial infarction at 0.2%; and cerebral haemorrhage, renal failure, and cardiac failure at 0.1% each. These percentages are reported as part of the serious-event information. The registry record does not give additional details about the events, their timing, or the basis for the listed percentages.

As a general distinction, seriousness describes an event's regulatory or clinical seriousness, whereas causality asks whether treatment is considered responsible. A serious event is not automatically an adverse drug reaction. The figures therefore describe reported safety events, but they do not by themselves establish that treatment caused them or permit comparison with an untreated group.

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

The record documents a completed survey of candesartan cilexetil use in hypertensive patients with metabolic-syndrome-related risk factors. It provides a defined safety endpoint, an at-risk count for adverse-event reporting, and listed serious-event terms. The main statistical value of this information is descriptive: it records the survey's stated population, intervention, outcome definitions, and reported safety figures.

The record does not provide a numerical result for the primary endpoint in the registry record for this analysis. Therefore, the number of participants reporting one or more investigator-attributed adverse drug reactions cannot be stated. Serious and other adverse-event counts cannot fill that gap because they are not identified as the primary endpoint. Similarly, the serious-event percentages describe listed terms but do not show whether events were judged related to treatment.

The exploratory goal was to assess relationships between risk factors and cerebrovascular or cardiovascular events. The registry entries list outcomes for obesity, blood glucose abnormalities, lipid abnormalities, and combinations of these factors, but do not include results for those analyses. No conclusion about the direction or strength of those relationships is supported by the record summary.

As a general statistical distinction, an observed event frequency in a treated survey population is not the same as a causal treatment effect. Establishing a treatment effect generally requires a suitable comparison and an analysis that addresses differences between groups. The registry states that this was not a randomized comparison, allocation was not stated, and the arms were not a like-for-like control comparison. Consequently, the event information should not be interpreted as evidence that treatment caused or prevented events.

The results also cannot establish how well the survey's observations apply to patients outside its defined population. The registry record does not provide enough detail about recruitment, missing follow-up, or analysis procedures to assess those questions. These limits do not erase the descriptive information, but they define what can reasonably be inferred from it.

14. Why This Trial Matters Statistically

This survey matters statistically because it illustrates the distinction between documenting safety experience and estimating a causal treatment effect. Its primary outcome is explicitly based on investigator-attributed adverse drug reactions, while the separately listed serious and other adverse-event figures describe broader safety categories. Keeping those definitions separate prevents counts with different meanings from being treated as interchangeable.

The record also makes the analysis population consequential. Enrollment is reported as 14151, the safety analysis set is defined as enrolled participants who completed the study, and the adverse-event information gives 13804 at risk. Those descriptions are not necessarily identical. Statistical interpretation depends on knowing which participants contribute to each result and how incomplete follow-up is handled; further details are not reported in the registry record.

The survey's exploratory focus on metabolic risk factors and cerebrovascular or cardiovascular events raises another important issue: associations observed in a clinical population do not automatically establish causes. Participants with different underlying risk factors may differ in other ways, and the record does not describe a randomized comparison that could address such differences. The exploratory framing appropriately signals that these relationships are not necessarily confirmatory tests.

Finally, the record illustrates why an endpoint definition, a denominator, and a comparison design must be read together. A count can be clearly defined yet still have limited causal interpretation, and an event percentage can be difficult to interpret without detailed follow-up and analysis information. The registry entries support a careful description of the survey, not a broader claim about treatment effects.

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.

Several trial-specific limitations constrain interpretation. The registry identifies this as a nonrandomized comparison and states that allocation was not reported. It also cautions that the arms are not a like-for-like control comparison. Accordingly, there is no basis in this record for treating any group contrast as a randomized estimate of treatment effect.

The primary outcome is based on the investigator's judgment that an adverse event was causally related to treatment. The registry record does not report the numerical primary outcome result in the registry record for this analysis. The serious and other adverse-event figures do not resolve this omission because they are not identified as the primary adverse drug reaction outcome.

The record reports enrollment of 14151, defines the safety analysis set as enrolled participants who completed the study, and lists 13804 at risk for adverse-event information. It does not explain how these populations relate, or report details of participant flow, missing follow-up, or outcome ascertainment. The effect of these unknowns cannot be assessed.

Although the survey's aim includes exploratory relationships between risk factors and cerebrovascular or cardiovascular events, no results for those analyses are included in the registry record. The record also does not report an analysis plan, multiplicity handling, model details, or study-specific sample-size justification. These omissions limit assessment of statistical precision, robustness, and whether analyses were planned in advance. The available safety terms and percentages remain descriptive and do not establish causation.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Blopress Tablets Specified Drug-use Survey "Hypertension: Survey on Patients With Metabolic Syndrome" — NCT02166697.
• Registry record last updated 2016-09-28; status last verified 2016-09.
• Results first posted 2016-07-11.
• 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.

19. Record Summary

The registry record identifies NCT02166697 as the completed Blopress Tablets Specified Drug-use Survey, titled “Hypertension: Survey on Patients With Metabolic Syndrome.” The official title refers to candesartan cilexetil tablets. Takeda is listed as sponsor. The condition is hypertension, enrollment is 14151, the recorded start is 2006-06, and primary completion is 2010-11.

The survey examined treatment status among hypertensive patients with metabolic-syndrome-related risk factors and explored risk-factor relationships with cerebrovascular or cardiovascular events. The intervention was oral candesartan cilexetil, described as 4-8 mg once daily with an increase up to 12 mg as necessary. The primary endpoint was participants reporting one or more adverse drug reactions from baseline up to 3 years.

The record lists serious and other adverse-event figures and selected serious-event terms, but the primary endpoint result and results for the exploratory risk-factor analyses are not reported in the registry record for this analysis. The registry describes no randomized, like-for-like control comparison.