According the World Health Organization, cardiovascular diseases , which affect the heart and blood vessels, are the vital cause of death worldwide.
The family history and lifestyle factors , such as smoking and an unhealthy diet, are well-established risk factors for cardiovascular disease, including coronary heart disease and stroke.
In addition to family history of CVD, largely influenced by genetic predisposition, also there is evidence showing that the acquainted structure , especially birth order, but not family size, can influence the risk of death from cardiovascular diseases .
However, only a few studies have analyzed the impact of the acquainted structure on non-fatal cardiovascular events and the truth is that a comprehensive understanding of the impact of the acquainted structure on CVD risk requires the inclusion of fatal cardiovascular events and not fatal.
In this sense, a large observational study, which involved people aged 30 to 58 years at the beginning, now shows that the number of siblings and the order of birth may influence the risk of total cardiovascular events during a follow-up period of 25 years.
Linkage of acquainted structure with cardiovascular risk
To obtain information on the acquainted structure, the researchers used the reliable source from the Swedish Multiple Generation Registry. This registry includes records of biological parents of more than 95% of the population born after 1931 and living in 1961 , which provides a set exceptionally large data set.
The study included data from 1.36 million men 1.32 million women ages 30 to 58 years in 1990 . In addition, the scientists determined the risk of fatal and non-fatal cardiovascular events, as well as the total mortality among these people , using data from records of deaths and hospital admissions between 1990 and 2015.
Factors such as socioeconomic level, educational level, marital status and conditions Medical , such as diabetes, can influence CVD risk. Thus, the team adjusted their analysis to take into account the influence of these variables and try to isolate the impact of the acquainted structure on the events cardiovascular.
Potential impact of the acquainted structure
In terms of family size , men and women with more than one sibling had a lower risk of death than those without siblings . Men with one or two siblings had a lower risk of cardiovascular events than those without siblings, while those with four or more siblings had a higher risk.
In the same way, women with three or more siblings had a higher risk of cardiovascular events and women with two or more siblings had a higher risk of coronary events.
In the case of birth order , the firstborn had a lower risk of cardiovascular and coronary events than those born later. On the contrary, first-borns had a higher risk of fashioned mortality than second siblings.
Despite these data, it is important to take into account that these only show an association, not a cause and effect relationship . Furthermore, due to lack of data, the researchers were also unable to take into account variables such as diagnostic procedures, socioeconomic status of parents , smoking, diet, and other lifestyle factors that they might have included in their CVD risk analysis.