Maternal stroke history tied to haemorrhagic stroke risk in T1D patients

Patients with type 1 diabetes (T1D) born to mothers with a history of stroke are at heightened risk of developing haemorrhagic stroke, a study reports.

The study used data from the Finnish Diabetic Nephropathy Study and included 4,011 individuals (mean age at baseline 37.6 years) followed for stroke events classified as either ischaemic or haemorrhagic. All individuals completed questionnaires about their parents’ medical history of hypertension, diabetes, stroke, and/or myocardial infarction.

Over a median follow-up of 12.4 years, 188 individuals (4.6 percent) had their first ever stroke; 134 were ischaemic and 54 haemorrhagic. Individuals who did vs did not develop stroke were likely to be older, men, smokers, and had a longer diabetes duration. Stroke patients also had higher blood pressure, unfavourable cholesterol levels, higher HbA1c, lower estimated glomerular filtration rate, and a history of diabetic kidney disease, retinal photocoagulation, and cardiovascular disease.

Multivariable Cox regression analysis revealed a positive association between a history of maternal stroke and risk of haemorrhagic stroke. Specifically, individuals whose mothers had experienced stroke had a more than twofold higher risk of developing haemorrhagic stroke (hazard ratio 2.86, 95 percent confidence interval 1.27–6.44; p=0.011).

Maternal stroke history did not modify the risk of ischaemic stroke.

Other parental risk factors appeared to have limited effect on the risk of stroke in offspring.