Neutrophil-to-Lymphocyte Ratio and Charlson Comorbidity Index for Predicting In-Hospital Mortality in Patients With Acute Ischemic Stroke Treated With Intravenous Thrombolysis: A Dual-Center Retrospective Cohort Study

Imagine the human body as a bustling city. When a major traffic jam blocks a vital artery, the city's power grid starts to flicker—that's a stroke, specifically an "ischemic" one where blood flow is cut off. To fix this, doctors can rush in with a special "fire extinguisher" called intravenous thrombolysis, a medicine that tries to dissolve the clot and restore the flow. But even with this powerful tool, the outcome isn't always a happy ending; sometimes, the damage is too deep, or the city is too fragile to recover.

To figure out who might survive and who might not, doctors have been looking for clues. Some clues are like checking the city's age and how badly the lights are flickering right now (how old the patient is and how severe their symptoms are). Other doctors have been hunting for "smoke signals" in the blood—tiny chemical markers that show if the city is on fire (inflammation) or if the buildings are already crumbling from old age (chronic diseases). Two of these popular clues are the Neutrophil-to-Lymphocyte Ratio (NLR), which is like a count of the body's emergency firefighters versus its peacekeepers, and the Charlson Comorbidity Index (CCI), which is basically a scorecard of all the other health problems a person is carrying. The big question is: do these smoke signals and scorecards actually help predict who will make it through the night, or are they just noise?

This study, conducted by researchers from Trabzon and Recep Tayyip Erdoğan Universities, decided to put these clues to the test. They looked back at the records of 713 adult patients who had received the "fire extinguisher" treatment for a stroke between 2022 and 2026. They wanted to see if the NLR (the inflammation score) or the CCI (the chronic disease score) could predict who would sadly pass away during their hospital stay, or if the old reliable clues—how old the patient was and how bad their stroke symptoms were at the very start—were still the only ones that truly mattered.

The researchers found that out of the 713 patients, about 14.9% (106 people) did not survive their hospital stay. When they started digging into the numbers, they found a clear pattern. The patients who passed away were, on average, significantly older (median age of 80) compared to those who survived (median age of 72). They also had much higher scores on the National Institutes of Health Stroke Scale (NIHSS) when they first walked in, meaning their neurological damage was more severe right from the start.

Here is where the story gets interesting for the "smoke signals." The researchers tested the NLR and the CCI to see if they were the secret keys to predicting death. In the beginning, it looked like the CCI (the chronic disease scorecard) might be important; patients who died did have higher scores. However, once the researchers adjusted for the fact that these patients were also older and had worse initial strokes, the CCI lost its magic. It turned out that the CCI wasn't an independent predictor; its effect was just a shadow of the patient's age and the severity of the stroke.

As for the NLR, the inflammation score, it didn't even make the cut. The study showed that the NLR was not a significant predictor of death at all. It was like trying to guess the weather by looking at a single cloud; it just didn't tell the whole story. When the researchers used a special statistical tool (called a ROC curve) to see which clue was the best at separating survivors from non-survivors, the NIHSS score (the initial stroke severity) was the clear winner, with a score of 0.692. The CCI came in second with a modest score of 0.612, and the NLR was so weak it barely registered at 0.534, which is essentially no better than flipping a coin.

The study also looked at what happened when they combined these clues. They wondered if having a high CCI and a high NIHSS, or a high NLR and a high NIHSS, would be a super-predictor. While these combinations looked scary in simple tests, they didn't hold up when the researchers checked them against the stronger factors like age and initial stroke severity. The NIHSS score remained the boss.

So, what's the takeaway? The researchers suggest that when a patient arrives at the hospital with a stroke and gets the clot-busting medicine, the most reliable crystal ball for predicting if they will survive the hospital stay is simply how old they are and how bad their stroke symptoms are right at that moment. The inflammation marker (NLR) and the chronic disease scorecard (CCI) didn't add any extra, independent power to the prediction once those main factors were taken into account. The study concludes that while these other markers are interesting, the severity of the neurological damage at the very beginning is still the strongest voice in the room when it comes to predicting the outcome.