Blood pressure and Smoking seem to influence the risk for bleeding in the brain significantly
A recent study by German and Dutch researchers have evidence of a connection between the Occurrence of aneurysmal bleeding in the brain and the risk factors hypertension and Smoking.
Risk factors of hypertension and Smoking
In a new study by German and Dutch scientists notes were supplied on a connection between the Occurrence of aneurysmal bleeding in the brain and the risk factors hypertension and Smoking. The comprehensive meta-analysis was published by researchers at the neurosurgical clinic of the University medical centre Mannheim (UMM), together with scientists from the Neurological clinic of the University of Utrecht, the Netherlands, in the journal “JAMA Neurology”.
A special Form of stroke
An aneurysmal subarachnoid hemorrhage (sah) is a special Form of the stroke, when the blood in the cerebrospinal fluid-filled subarachnoid space, which is the brain and spinal surrounds mark protective.
In a communication from the UMM explains, this Form of bleeding within the brain most often when an aneurysm tears, a SAC-like enlargement of an artery to the brain base.
Subarachnoid hemorrhage account for about five percent of all strokes, but the consequences are most threatening:
Half of the patients younger than 55 years, one-third die within the first days to weeks after the onset of bleeding and about a third of the Survivors will remain permanently in need of help.
The meta-analysis of the German and Dutch scientists reveals for the first time, a global decrease in the occurrence of aneurysm-related bleeding in the brain parallel to the decrease of high blood pressure and Smoking.
The aim of the researchers was not only to light in the both temporally as well as spatially appear to be quite heterogeneous distribution of the incidence of SAB, but also potential determinants to prove, which could be a decline in this disease.
Number of diseases has decreased
The starting point of the project were recently published, and in part conflicting data from different register-based or regional studies that document a decline in the occurrence of Subarachnoid hemorrhage.
In the systematic review meta-data of all the global, population-based stroke were studies of the last 60 years. The study recorded the Occurrence of aneurysmal bleeding in the brain, regional, and their frequency over time.
In addition, the meta-analysis provides for the first time, the development of the factors of blood pressure and Smoking in Relation to the SAB incidence.
There is evidence of a connection between the Occurrence of aneurysmal bleeding in the brain and the risk factors hypertension and Smoking.
Specifically, the analysis of data from 75 trials with a total of more than 8,000 people from 32 countries, that the Occurrence of bleeding in the brain in the past few decades has significantly decreased:
Between 1980 and 2010, the incidence decreased for aneurysmal subarachnoid hemorrhage in the world, a total of about 40 percent. Here, however, great regional differences have been detected:
The incidence in Europe declined by 41 percent, in Asia by 46 percent and North America 14 percent. However, the incidence of SAB in Japan rose in the last three decades, to 59 percent. The Occurrence of a SAB is also distributed according to age and gender.
Decrease parallel to the decrease of the systolic blood pressure and Smoking prevalence
It is striking that the development and acceptance of the SAB extends worldwide incidence parallel to the decrease of the systolic blood pressure and Smoking prevalence during the same period.
“A mind game: Would be the acceptance of the SAB incidence is actually directly linked to the reduction of the systolic blood pressure in conjunction, this would mean that the SAB-incidence would decrease with any decrease in blood pressure of 1 mmHg to 7.1 per cent,” explains the first author of the scientific publication, Professor Dr. Nima Etminan.
“And based on the prevalence of Smoking meant that the SAB-incidence would decrease by 2.4 percent per percent decrease in Smoking prevalence,” says the chief physician of the Neurosurgical clinic of the UMM.
Of course, the parallel development of blood pressure and prevalence of Smoking with the incidence of Subarachnoid hemorrhage, a causal connection only suspect.
A proof is not able to deliver the existing data, but quantitative data for these risk factors on a population basis or at the level of individual patients would be necessary.
Nevertheless, in the study found the Association supports the preventive approaches to control the risk factors of hypertension and Smoking, to reduce the risk of aneurysmal bleeding in the brain.
Risk for aneurysmal bleeding in the brain reduce
In Parallel with this, the authors are currently also the scientific question of whether a reduction in blood pressure in patients with accidentally discovered aneurysms, which are not treated in the primary but by means of imaging are controlled, favorable to the development of aneurysms of the impact.
This is done in the context of prospective Phase III study PROTECT-U (www.protect-u-trial.com/) in various neuro-vascular centres in Germany, the Netherlands and soon also in Canada.
The present work provides starting points for further studies, the results of which – if you are in the appropriate strategies for the primary prevention of lead – in fact, could help to reduce the risk of aneurysmal bleeding in the brain:
This would be a more detailed investigation of the regional differences in the incidence of SAB and the reduction of the regional differences in age – and gender-specific incidences and their relationship to behavior to a more precise, quantitative data on the smoke. (ad)