Systemic Immune-Inflamation Index and Mortality in ICU Patients

NCT07493759 | Completed

• 1 other identifier: B.30.2.ATA.0.01.00/804
• Study Type: observational
• Target: 570
• Locations: 1 country
• Sites: 1

Brief 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. 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.

Conditions

Critical Illness; Sepsis

Keywords

intensive care unit; systemic immune-inflammation index; mortality

Outcome Measures

Primary Outcomes (1)

• ICU Mortality Rate

  All-cause mortality during ICU stay, compared between patients with high vs. low SII values

  Duration of ICU stay (up to 90 days)

Secondary Outcomes (3)

• Systemic Immune-Inflammation Index (SII)

  At ICU admission (Day 0)

• APACHE II Score

  First 24 hours of ICU admission

• Glasgow Coma Scale (GCS) Score

  At ICU admission (Day 0)

Study Arms (2)

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.

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.

Other: Systemic Immune-Inflammation Index (SII)

Interventions

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.

High Systemic Immune-Inflammation Index (High SII); Low Systemic Immune-Inflammation Index (Low SII)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

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

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• Ataturk University: lead

Study Sites (1)

Atatürk University Faculty of Medicine Hospital

Erzurum, 25100, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Critical Illness; Sepsis

Condition Hierarchy (Ancestors)

Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Infections; Systemic Inflammatory Response Syndrome; Inflammation

Study Officials

• nazim doğan, MD

  Atatürk University Faculty of Medicine, Department of Anesthesiology and Reanimation

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Prof. Dr.

Study Record Dates

• First Submitted: February 19, 2026
• First Posted: March 25, 2026
• Study Start: December 1, 2025
• Primary Completion: March 18, 2026
• Study Completion: March 18, 2026
• Last Updated: March 25, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)