Continued use of statins may help prevent delirium in critically ill patients

Continued use of statins may help prevent delirium in critically ill patients who received statins before hospital admission, according to a new study of 470 intensive care patients in the UK.

"This is the first study using a validated delirium screening tool, the Confusion Assessment Method-ICU (CAM-ICU), to show that the administration of statins reduces delirium in these patients," said lead author Valerie J Page MB ChB, of the Watford General Hospital in Watford, UK. "This benefit may be mediated by a reduction in systemic inflammation."

The findings were published online ahead of print publication in the American Thoracic Society's American Journal of Respiratory and Critical Care Medicine.

Of the 470 patients included in the study, 151 received statins. Statins were only administered to patients who had received statins prior to admission.

After adjustment for age, sex and illness severity, administration of statins the previous evening was associated with a significantly lower risk of delirium and a concomitant reduction in serum C-reactive protein (CRP), a marker of systemic inflammation, the following day. The strength of the relationship between statin use and a lower risk of delirium was reduced when CRP was adjusted for.

"Although the pathogenesis of delirium is not fully understood, these data are consistent with a neuro-inflammatory cause and suggest that the anti-inflammatory effects of statins may contribute to the effects of statin treatment on delirium," said Dr. Page. "Our study on statin use and the risk of delirium in critically ill subjects included extensive data on a large, broadly representative population of consecutive intensive care patients, increasing its strength."

Study limitations include the possibility that not all potential confounding factors were adjusted for and the limits of cognitive assessment tools in critically ill patients.

"Our findings suggest that statin treatment should be continued to help prevent delirium in critically ill patients who received statins before being admitted," said Dr. Page.

"The relationship between statin therapy and delirium and the mechanisms underlying this relationship are the subject of an ongoing randomized, placebo-controlled study in critically ill ventilated patients."