Mechanical thrombectomy is associated with poor outcomes in elderly patients with ischaemic stroke (IS) and large vessel occlusion (LVO), a study has found.

New findings from a Dutch registry suggest that the good functional outcomes seen with mechanical thrombectomy in randomised controlled trials may not extend to people over the age of 80 in a real world setting.

Neurologists at Amsterdam University Medical Centre found that patients with IS over the age of 80 had significantly worse outcomes than younger patients after undergoing endovascular thrombectomy, with a notable increase in mortality within the first 30 days after stroke.

Using data from the Multicentre Randomised Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) registry, they evaluated the outcome of mechanical thrombectomy in 1,526 elderly patients with IS and LVO involving the anterior circulation between 2014 and 2016.

Around  25% (380) patients were over the age of 80 and these patients were more likely to have premorbid disability, a greater burden of risk factors and comorbid conditions, more severe strokes, worse collaterals and experienced longer time from stroke onset to groin puncture and higher frequency of failure to reach the target occlusion.

While there were no differences between age groups in rates of successful reperfusion or symptomatic intracerebral haemorrhage, older patients had worse mortality functional outcomes at 90 days compared to younger patients.

The risk of death was three times higher (50.9% vs 21.8%, adjusted Odds Ratio 3.12,) and the odds of good functional outcome were 59% lower (20.3% vs 45.6%, adjusted cOR 0.41) in older vs younger patients.

The excess mortality peaked at 10 days after stroke in older patients, suggesting that it was driven upfront by worse periprocedural outcomes or stroke-related factors rather than longer-term complications, the study authors said in Neurology.

Nevertheless, they noted that one in five older adults achieved a good functional outcome after mechanical thrombectomy, and the risk of severe handicap was not higher in older patients

Successful reperfusion was also more strongly associated with a shift toward good functional outcome in older adults than in younger patients (adjusted OR 3.22).

“When no reperfusion is achieved in [older] patients, chances of surviving stroke are small. Younger patients in whom no reperfusion is achieved, however, will more likely survive the stroke, even in the absence of reperfusion,” they explained.

An accompanying commentary said the outcomes seen in a real world population should be considered when selecting elderly stroke patients for endovascular thrombectomy.

“Current guidelines do not preclude mechanical thrombectomy in elderly patients; however, for this age category, more uncertainties remain for the time window beyond 6 hours and for patients with significant prestroke disability,” it noted.

The findings showed the need for better data in older patients who were most likely to experience a stroke, and for whom validated outcome prediction models would help physicians in decision-making, the authors concluded.