Objective:

To investigate the association and explore the specific non-linear relationship between preoperative platelet to white blood cell ratio (PWR) and 30-day postoperative mortality in adult patients undergoing intracranial tumor craniotomy.

Approach:

• Study Design: Retrospective cohort study utilizing data from the ACS NSQIP database involving 9,434 patients.
• Statistical Analysis: Cox proportional hazards models were used to assess the association between preoperative PWR and 30-day mortality, including non-linear relationships through smooth curve fitting and two-piecewise Cox regression.

Key Findings:

• Mean preoperative PWR was 27.044 ± 12.564.
• 30-day postoperative mortality rate was 3.148% (297/9434).
• Preoperative PWR was inversely associated with 30-day postoperative mortality (HR = 0.978, 95% CI: 0.967–0.990).
• Non-linear association observed with an inflection point at PWR of 20.111; below this, each unit increase in PWR was associated with an 8% decrease in mortality risk (HR = 0.920, 95% CI: 0.892–0.949).
• Above the inflection point, the association was not significant (HR = 0.997, 95% CI: 0.984–1.011).

Interpretation:

The study presents a non-linear relationship between preoperative PWR and 30-day postoperative mortality, with lower PWR levels associated with higher mortality risk in this population.

Limitations:

• Retrospective design may introduce biases.
• Data sourced from a single database may limit generalizability.

Conclusion:

The study demonstrates an inverse and non-linear association between preoperative PWR and 30-day postoperative mortality in adults undergoing intracranial tumor craniotomy.