Stroke: Statin use in hospital linked to improved post-stroke survival
Treating ischemic stroke patients with statins at the beginning of hospitalization and avoiding interruptions in statin use for stroke patients who already were taking statins may be a prudent course of care, based on results of a study published online Oct. 20 in Stroke. The observational study found a strong association between early statin use in ischemic stroke patients and improved survival as well as an association between statin withdrawal and worsened survival.

Small clinical trials have shown that statin use before the onset of an ischemic stroke has been associated with improved outcomes, while statin withdrawal during stroke hospitalization may worsen outcomes, Alexander C. Flint, MD, PhD, of the department of neuroscience at Kaiser Permanente in Redwood City, Calif., and colleagues wrote. They noted that statin therapy is recommended for secondary stroke prevention but guidelines fail to address statin use in a hospital setting.

To study the relationship between statin use before and during stroke hospitalization and survival after a stroke, they designed an observational study based on records from Kaiser Permanente Northern California (KPNC) that were submitted between 2000 and 2007. Patients included in the study had a primary discharge diagnosis of ischemic stroke, were more than 50 years old, had no prior history of stroke during the search period, and were members of the KPNC health plan for at least one year.

The KPNC computer system captured all inpatient and outpatient prescriptions, which allowed the researchers to study statin use before and during stroke hospitalization.

They analyzed 12,689 records for patients admitted for ischemic stroke in 17 hospitals during the study period. They applied a multivariable survival analysis as well as an instrumental variable model known as a grouped-treatment analysis to avoid patient-level confounding that can occur in observational studies.

Of the patients given statins while in hospital, 70 percent were treated during the first 24 hours of admission; 21 percent were treated during the second 24 hours; and 9 percent were treated after the first 48 hours. Approximately 30 percent of the stroke patients were taking statins before admission, and 13 percent experienced statin withdrawal while in hospital.

Flint and colleagues found that statin use before and during hospitalization was associated with improved post-stroke survival while statin withdrawal worsened poststroke survival. Higher doses showed a greater benefit than lower doses, and earlier in-hospital treatment further improved survival.

“Because statins have effects on several biochemical pathways of relevance to the ischemic neurovascular unit, statins may have a neuroprotective effect during the acute phase of hospitalization for ischemic stroke,” the authors wrote.

The grouped-treatment analysis confirmed the primary findings but the statin withdrawal results suggested that some individual patient confounding was taking place. Besides limitations related to the observational design, they noted that they could track only mortality and not functional status and quality of life. Nonetheless, they argued that the findings should be considered in clinical decisions.

“Because we found a strong association between early hospital stain use and long-term survival, it seems clinically prudent to treat patients with ischemic stroke with a statin from the beginning of stroke hospitalization,” they advised. “Given the association between statin withdrawal and worsened survival, care should be taken to avoid interruption of statin therapy among patients taking a statin before hospitalization.”