Cholesterol ‘paradox’ in survival after stroke thrombolysis

More stuff to show that they really have no clue on how much cholesterol we really need.
http://www.medwire-news.md/39/96251/Stroke/Cholesterol_%E2%80%98paradox%E2%80%99_in_survival_after_stroke_thrombolysis.html
Cholesterol levels in patients with ischemic stroke are inversely related to survival after intravenous thrombolysis, report Spanish researchers.

"The mechanism of this apparent paradox, common to both ischaemic and hemorrhagic strokes, remains unexplained, and merits further research," say Jaume Roquer (Hospital del Mar, Barcelona) and colleagues.

The team measured cholesterol levels in 220 patients with ischemic stroke who underwent intravenous thrombolysis within 4.5 hours of symptom onset. In all, 15% of patients died within 3 months of treatment.

As expected, stroke severity, as measured on the National Institutes of Health Stroke Scale (NIHSS), was the most significant determinant of patient survival at 3 months in all multivariate models. NIHSS score did not correlate with high-density lipoprotein cholesterol, but correlated inversely with patients' levels of total cholesterol, triglycerides, and low-density lipoprotein cholesterol.

Despite this, total cholesterol levels were significantly inversely associated with survival, and remained so after accounting for stroke severity.

Other lipid measures were not significantly associated with mortality, but for total cholesterol, 3-month mortality fell from 25.7% in the lowest cholesterol tertile (<155 mg/dL; 4.0 mmol/L) to 13.7% in the middle tertile (155-192 mg/dL; 4.0-4.9 mmol/L) and just 5.5% in the highest tertile (>192 mg/dL; 4.9 mmol/L).

"Our study does not allow us to identify the reason why low cholesterol is associated with increased mortality after [ischemic stroke], although we could hypothesize that this is an epiphenomenon or a surrogate marker of poor prognosis rather than an effect related to cholesterol levels," say Roquer et al in the European Journal of Neurology.

However, they note that cholesterol is essential for cell membrane function, and has many other important roles, making it "plausible" that high plasma cholesterol levels could be neuroprotective.