Polycystic kidney disease linked to intracranial aneurysm risk
MedWire News: The prevalence of unruptured intracranial aneurysms may be increased in people with polycystic kidney disease, study findings suggest.
Overall, the researchers calculate an expected prevalence of unruptured intracranial aneurysms of 3.2% in a population of 50% men, aged an average of 50 years, and without comorbidities.
Their estimate is based on data from 68 studies, which included 1450 unruptured intracranial aneurysms in 94,912 patients from 21 countries. Ale Algra (University Medical Center Utrecht, The Netherlands) and team note that this estimate is higher than the 2.3% estimate derived from their previous study, in 1998.
"This difference can be explained by our correction for age and sex, inclusion of more recent studies with higher quality imaging techniques, and inclusion of fewer retrospective autopsy studies," they write in The Lancet Neurology.
In the current study, the prevalence of unruptured intracranial aneurysms was increased 6.9-fold for people with autosomal dominant polycystic disease and 3.4-fold for those with a family history of subarachnoid hemorrhage or intracranial aneurysms.
There were also nonsignificant increases for people with pituitary adenoma or atherosclerosis, contrasting with the significant positive associations found in the 1998 study.
"Our present findings are probably more accurate, because we included three times as many studies as before and, more importantly, we were able to adjust prevalence ratios for sex and age," say Algra et al.
Women had a 1.61-fold higher prevalence of aneurysms than did men, which was largely explained by a 2.2-fold increased prevalence among women older than 50 years, relative to men of the same age.
"Our finding that older women might have a higher prevalence is possibly an important clue for how aneurysms are formed and future well designed studies should focus on the role of estrogen in the pathogenesis of unruptured intracranial aneurysms," says the team.
In a related commentary, Seppo Juvela (University of Helsinki, Finland) highlighted the absence of information on several important confounders.
"Of all subarachnoid hemorrhages, about 40% are attributable to smoking, 25% to hypertension, and 15-20% to heavy alcohol consumption, but less than 5% to first-degree family history of subarachnoid hemorrhage or intracranial aneurysm, and polycystic kidney disease as a risk factor for subarachnoid hemorrhage is rare," he said.
"In future studies of the prevalence of intracranial aneurysms, cigarette smoking status, history of hypertension, and alcohol consumption should be taken into account, although classification of patients might be more difficult than for variables that do not change during a lifetime."
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By Eleanor McDermid