Stopping statins after stroke poses risk for recurrent stroke
Stopping statins within 6 months after a first ischaemic stroke was associated with an increased risk of recurrent stroke at 1 year compared with those who continued with the therapy, a new study showed.
“Discontinuation of statin treatment in patients with ischaemic stroke should be strongly discouraged in any stage, acute or chronic, of stroke,” said lead author Dr Lee Meng from the Department of Neurology at Chang Gung University College of Medicine in Taiwan.
Analysing data from 45,151 ischaemic stroke patients, the researchers found that almost one-fifth of patients (18.5 percent) discontinued statins and 7 percent of the patients were on reduced statin dose between 3 and 6 months after the index event. Within the 1-year follow-up, 2,120 recurrent strokes were documented. [J Am Heart Assoc 2017;doi:10.1161/JAHA.117.005658]
Compared with patients who maintained their initial statin therapy, those who stopped taking statins had a 42 percent higher risk of recurrent ischaemic or haemorrhagic stroke at 1 year (6.2 percent vs 4.4 percent, adjusted hazard ratio [HR], 1.42; p<0.0001).
Stopping statins was also associated with higher risks of all-cause mortality (HR, 1.37; p=0.003), all major events (HR, 1.38; p<0.0001), and any hospitalization (HR, 1.19; p<0.0001).
However, there were no significant impacts on intracerebral haemorrhage (HR, 1.19; p=0.30) and myocardial infarction (HR, 0.96; p=0.80).
“These findings suggest that providers and atherosclerotic stroke patients should not discontinue statin therapy unless there is a highly compelling reason for doing so,” urged Lee and co-authors.
The AHA* guidelines recommend intensive statin therapy for patients with LDL-cholesterol level >100 mg/dL who had experienced a transient ischaemic attack or ischaemic stroke, but do not recommend discontinuing statins after achieving a certain target LDL-cholesterol level in most patients, depending on individual risk.
“Physicians also need to increase awareness among stroke patients about the potential risk of discontinuing their medications and to encourage greater adherence,” the researchers advised.
On the other hand, lowering statin dose was not associated with additional risk of recurrent stroke (HR, 0.94; p=0.47), nor were the risks of all-cause mortality (HR, 0.97; p=0.88), all major events (HR, 0.94; p=0.46), intracerebral haemorrhage (HR, 0.65; p=0.19), and myocardial infarction (HR, 1.01; p=0.98) significantly affected.
“Shifting to low-intensity statin therapy could be an alternative for stroke patients not able to tolerate moderate- or high-intensity statin therapy in the years following a stroke,” Lee suggested.
The retrospective multicentre cohort study included patients who were prescribed a statin of moderate- or high-intensity within 90 days of discharge after hospitalization for ischaemic stroke based on data from the Taiwan National Health Insurance Research Database.
To minimized bias that could arise from the “healthy user” effect ─whereby patients stopping statins were systematically sicker than those who continued the therapy ─ patients who discontinued antithrombotic therapy were excluded. Baseline characteristics were also balanced among the groups, including receipt of antihypertensive agents.
Propensity-matching analysis revealed similar results as those in the multivariate analyses above.
“It has been shown that statin-related side effects often lead to statin discontinuation, but … [s]ymptoms occurring while on a statin may not necessarily be related to its use, may eventually be tolerated by the patient, may not recur with a rechallenge, or may be specific to individual statins rather than the entire drug class,” according to Lee and co-authors. [Ann Intern Med 2013;158:526-534]
“Additional prospective studies should be carried out to clarify the underlying mechanisms, such as LDL-cholesterol rebound and/or inflammation, linking statin discontinuation to higher risk of recurrent stroke,” they added.