Critical IllnessNCT07493759
Systemic Immune-Inflamation Index and Mortality in ICU Patients
An observational study of Critical Illness and Sepsis, run by Ataturk University at 1 site in Turkey (Türkiye).
Trial summary
Systemic Immune-Inflammation Index (SII) is a hemogram-derived biomarker reflecting the balance between systemic inflammation and immune response. In critically ill patients, inflammatory burden at admission may play a key role in prognosis. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Critical Illness, Sepsis
- What is being tested?
- Systemic Immune-Inflammation Index (SII)
- How many people
- 570 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 1 Dec 2025to 18 Mar 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adult patients aged 18 years or older admitted to the reanimation intensive care unit for infectious or non-infectious critical illness, with available admission laboratory data
Who may be able to join
- Age 18 years or older
- Admission to the reanimation intensive care unit
- Availability of admission complete blood count and biochemical laboratory data
- Admission due to infectious or non-infectious critical illness
Who cannot join
- Pregnancy
- Hematologic malignancy
- Active chemotherapy
- Chronic immunosuppression
- Pulse steroid therapy
- Known thrombocytopenia (platelet count <50×10^9/L)
- Massive bleeding or massive transfusion within the first 24 hours of ICU admission
- Incomplete clinical or laboratory data
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Atatürk University Faculty of Medicine Hospital
Erzurum, 25100
About this study
Official title: The Relationship Between Systematic Inflammatory Index (SII) and Mortality in Patients Admitted to the Non-Interventional Clinical Research Ethics Committee for Evalation
Systemic Immune-Inflammation Index (SII) is a hemogram-derived biomarker reflecting the balance between systemic inflammation and immune response. In critically ill patients, inflammatory burden at admission may play a key role in prognosis. This retrospective cohort study aims to evaluate the association between admission SII levels and intensive care unit (ICU) mortality in adult patients admitted to a reanimation ICU. Secondary objectives include comparison of mortality according to infectious versus non-infectious admission diagnoses and assessment of the relationship between SII and established severity scores, including APACHE II and Glasgow Coma Scale (GCS). The findings may support the use of SII as a rapid, inexpensive prognostic marker in critically ill patients.
Read the detailed description
Systemic inflammation is a fundamental component of critical illness and has a strong association with disease severity and mortality in intensive care units. The Systemic Immune-Inflammation Index (SII), calculated from neutrophil, lymphocyte, and platelet counts, has emerged as a quantitative marker of systemic immune-inflammatory status. While SII has been studied in various clinical settings, its prognostic value in reanimation ICU patients remains insufficiently defined.
This study is designed as a single-center, retrospective, non-interventional cohort study conducted in the Reanimation Intensive Care Unit of Atatürk University Research Hospital. Adult patients (≥18 years) admitted to the ICU for infectious or non-infectious critical illnesses will be evaluated through retrospective review of hospital electronic medical records (ENLİL Hospital Information Management System).
Patients will be included if admission laboratory data, including complete blood count and biochemical parameters, are available. Exclusion criteria include pregnancy, hematologic malignancy, active chemotherapy, chronic immunosuppression, pulse steroid therapy, known severe thrombocytopenia (<50×10⁹/L), massive bleeding or massive transfusion within the first 24 hours, and incomplete clinical or laboratory data.
The primary outcome of the study is the association between admission SII levels and ICU mortality. Secondary outcomes include comparison of mortality rates between infectious and non-infectious admission diagnoses, evaluation of correlations between SII and APACHE II and GCS scores, and assessment of whether elevated SII is an independent risk factor for ICU mortality.
Sample size calculation was performed using G*Power software based on a reference population study, assuming a mean SII value of 515±170 in the control group. To detect a 40-unit difference in SII between infectious and non-infectious groups with 80% power and a 95% confidence level, a minimum of 285 patients per group (total ≥570 patients) is required.
Statistical analysis will be conducted using appropriate correlation tests (Pearson or Spearman) based on data distribution. As a retrospective, non-interventional study, no additional procedures will be performed, and patient confidentiality will be strictly maintained. The study involves no external funding and no declared conflicts of interest.
- Conditions
- Critical Illness, Sepsis
- Being tested
- Systemic Immune-Inflammation Index (SII)
- Keywords
- intensive care unit, systemic immune-inflammation index, mortality
- Medical subject headings
- Critical Illness, Sepsis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Systemic Immune-Inflammation Index (SII)Other
Systemic immune-inflammation index (SII) calculated at intensive care unit admission using routine complete blood count parameters. SII is calculated as platelet count multiplied by neutrophil count divided by lymphocyte count. Patients are classified into high and low SII groups based on a predefined cutoff value. No therapeutic intervention is administered as part of the study.
| Study group | Role | What they receive |
|---|---|---|
| High Systemic Immune-Inflammation Index (High SII) | Critically ill patients admitted to the intensive care unit with a systemic immune-inflammation index (SII) above the predefined cutoff value calculated at ICU admission. SII is calculated as platelet count × neutrophil count / lymphocyte count. Outcomes including ICU mortality are evaluated observationally without any intervention. Receives: Other: Systemic Immune-Inflammation Index (SII) | |
| Low Systemic Immune-Inflammation Index (Low SII) | Critically ill patients admitted to the intensive care unit with a systemic immune-inflammation index (SII) at or below the predefined cutoff value calculated at ICU admission. SII is calculated as platelet count × neutrophil count / lymphocyte count. Outcomes including ICU mortality are evaluated observationally without any intervention. Receives: Other: Systemic Immune-Inflammation Index (SII) |
What is being measured
The primary outcome is the main question the study is designed to answer.
ICU Mortality Rate
All-cause mortality during ICU stay, compared between patients with high vs. low SII values
Measured: Duration of ICU stay (up to 90 days)
Secondary outcomes (3)
Systemic Immune-Inflammation Index (SII)
SII calculated as neutrophil count × platelet count / lymphocyte count from admission peripheral blood sample
Measured: At ICU admission (Day 0)
APACHE II Score
Correlation between admission SII level and APACHE II score
Measured: First 24 hours of ICU admission
Glasgow Coma Scale (GCS) Score
Correlation between admission SII level and GCS score
Measured: At ICU admission (Day 0)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Mar 2026
- Study start1 Dec 2025
- Primary completion18 Mar 2026
- Study completion18 Mar 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Critical IllnessStudies of the same condition, open and under way.
- More trials run by Ataturk UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Retrospective
- Enrolment
- 570 participants (actual)
Sponsor and investigators
- Lead sponsor
- Ataturk University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Nazim Dogan Prof. M.D, Ataturk University
- Investigators
- nazim doğan, MD, Principal investigator, Atatürk University Faculty of Medicine, Department of Anesthesiology and Reanimation
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07493759
- Sponsor's protocol ID
- B.30.2.ATA.0.01.00/804
- Status last verified
- Mar 2026
- First submitted
- 19 Feb 2026
- Last updated
- 25 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 25 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Relationship Between Systematic Inflammatory Index (SII) and Mortality in Patients Admitted to the Non-Interventional Clinical Research Ethics Committee for Evalation
- ClinicalTrials.gov ID
- NCT07493759
- Acronym / sponsor ID
- B.30.2.ATA.0.01.00/804
- Conditions
- Critical Illness, Sepsis
- Keywords
- intensive care unit, systemic immune-inflammation index, mortality
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 570 participants (actual)
- Lead sponsor
- Ataturk UniversityUniversity, hospital or other
- Study start
- 1 Dec 2025 (actual)
- Primary completion
- 18 Mar 2026 (actual)
- Study completion
- 18 Mar 2026 (actual)
- First posted
- 25 Mar 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Systemic Immune-Inflammation Index (SII) is a hemogram-derived biomarker reflecting the balance between systemic inflammation and immune response. In critically ill patients, inflammatory burden at admission may play a key role in prognosis. This retrospective cohort study aims to evaluate the association between admission SII levels and intensive care unit (ICU) mortality in adult patients admitted to a reanimation ICU. Secondary objectives include comparison of mortality according to infectious versus non-infectious admission diagnoses and assessment of the relationship between SII and established severity scores, including APACHE II and Glasgow Coma Scale (GCS). The findings may support the use of SII as a rapid, inexpensive prognostic marker in critically ill patients.
Detailed description
Systemic inflammation is a fundamental component of critical illness and has a strong association with disease severity and mortality in intensive care units. The Systemic Immune-Inflammation Index (SII), calculated from neutrophil, lymphocyte, and platelet counts, has emerged as a quantitative marker of systemic immune-inflammatory status. While SII has been studied in various clinical settings, its prognostic value in reanimation ICU patients remains insufficiently defined.
This study is designed as a single-center, retrospective, non-interventional cohort study conducted in the Reanimation Intensive Care Unit of Atatürk University Research Hospital. Adult patients (≥18 years) admitted to the ICU for infectious or non-infectious critical illnesses will be evaluated through retrospective review of hospital electronic medical records (ENLİL Hospital Information Management System).
Patients will be included if admission laboratory data, including complete blood count and biochemical parameters, are available. Exclusion criteria include pregnancy, hematologic malignancy, active chemotherapy, chronic immunosuppression, pulse steroid therapy, known severe thrombocytopenia (<50×10⁹/L), massive bleeding or massive transfusion within the first 24 hours, and incomplete clinical or laboratory data.
The primary outcome of the study is the association between admission SII levels and ICU mortality. Secondary outcomes include comparison of mortality rates between infectious and non-infectious admission diagnoses, evaluation of correlations between SII and APACHE II and GCS scores, and assessment of whether elevated SII is an independent risk factor for ICU mortality.
Sample size calculation was performed using G*Power software based on a reference population study, assuming a mean SII value of 515±170 in the control group. To detect a 40-unit difference in SII between infectious and non-infectious groups with 80% power and a 95% confidence level, a minimum of 285 patients per group (total ≥570 patients) is required.
Statistical analysis will be conducted using appropriate correlation tests (Pearson or Spearman) based on data distribution. As a retrospective, non-interventional study, no additional procedures will be performed, and patient confidentiality will be strictly maintained. The study involves no external funding and no declared conflicts of interest.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| High Systemic Immune-Inflammation Index (High SII) | – | Other: Systemic Immune-Inflammation Index (SII)Critically ill patients admitted to the intensive care unit with a systemic immune-inflammation index (SII) above the predefined cutoff value calculated at ICU admission. SII is calculated as platelet count × neutrophil count / lymphocyte count. Outcomes including ICU mortality are evaluated observationally without any intervention. |
| Low Systemic Immune-Inflammation Index (Low SII) | – | Other: Systemic Immune-Inflammation Index (SII)Critically ill patients admitted to the intensive care unit with a systemic immune-inflammation index (SII) at or below the predefined cutoff value calculated at ICU admission. SII is calculated as platelet count × neutrophil count / lymphocyte count. Outcomes including ICU mortality are evaluated observationally without any intervention. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult patients aged 18 years or older admitted to the reanimation intensive care unit for infectious or non-infectious critical illness, with available admission laboratory data
Key inclusion criteria (4 listed)
- Age 18 years or older
- Admission to the reanimation intensive care unit
- Availability of admission complete blood count and biochemical laboratory data
- Admission due to infectious or non-infectious critical illness
Key exclusion criteria (8 listed)
- Pregnancy
- Hematologic malignancy
- Active chemotherapy
- Chronic immunosuppression
- Pulse steroid therapy
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Systemic Immune-Inflammation Index (SII)Systemic immune-inflammation index (SII) calculated at intensive care unit admission using routine complete blood count parameters. SII is calculated as platelet count multiplied by neutrophil count divided by lymphocyte count. Patients are classified into high and low SII groups based on a predefined cutoff value. No therapeutic intervention is administered as part of the study. | Other | High Systemic Immune-Inflammation Index (High SII), Low Systemic Immune-Inflammation Index (Low SII) |
Primary outcome
ICU Mortality Rate
Time frame: Duration of ICU stay (up to 90 days)
All-cause mortality during ICU stay, compared between patients with high vs. low SII values
3 secondary outcomes
Systemic Immune-Inflammation Index (SII)
Time frame: At ICU admission (Day 0)
APACHE II Score
Time frame: First 24 hours of ICU admission
Glasgow Coma Scale (GCS) Score
Time frame: At ICU admission (Day 0)
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 25 Mar 2026.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
nazim doğan, MD principal investigator
Atatürk University Faculty of Medicine, Department of Anesthesiology and Reanimation
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Critical Illness and Sepsis, run by Ataturk University at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 25 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
ICU Mortality Rate (time frame: Duration of ICU stay (up to 90 days)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 25 Mar 2026.