Systemic Inflammation Markers: No Predictor for Pain in SAH

A recent multicenter study found that early systemic inflammatory markers did not predict subsequent ICU pain burden after aneurysmal subarachnoid hemorrhage (SAH), a finding with direct implications for triage and analgesic planning.

Investigators performed a retrospective multicenter observational cohort study, abstracting early post‑ictus inflammatory biomarkers and ICU pain scores from electronic health records. The analysis included 523 patients and used ordinal logistic regression with multivariable adjustment across predefined covariates. The primary endpoint was average daily ICU pain burden (patients divided into quartiles); sensitivity analyses were restricted to patients able to verbally report pain. The biomarker panel comprised C‑reactive protein (CRP), white blood cell count (WBC), and interleukin‑6 (IL‑6). Both univariate and multivariable models were applied to identify predictors.

The authors report no association between early systemic inflammatory markers and later ICU pain burden. In adjusted multivariable models, younger age (per‑year odds ratio 0.99, 95% CI 0.97–0.99) and chronic preadmission opioid use (odds ratio 1.69, 95% CI 1.11–2.58) were associated with higher ICU pain burden; inflammatory blood biomarkers showed no signal in uni- or multivariable analyses.

Secondary and adjusted analyses consistently identified younger age and chronic opioid use as predictors of greater ICU pain burden. That pattern departs from a simple mechanistic expectation that systemic inflammation drives nociceptive amplification and instead aligns with clinical literature emphasizing demographic and opioid‑history effects on inpatient pain trajectories.

These results argue against using early systemic inflammatory biomarkers to triage or anticipate analgesic needs after SAH. Instead, bedside pain assessment and careful medication‑history review—with attention to younger patients and those with chronic opioid exposure—better flag patients at risk for higher ICU pain burden and can guide allocation of analgesic resources.

Replication and prospective validation are needed to refine triage protocols and to evaluate targeted, opioid‑sparing analgesia pathways for patients identified at higher risk by age and opioid history.