The following 3 hypotheses were tested using likelihood ratio tests: The follow-up continued until death or the end of a fixed follow-up period or, in occasional cases, loss to follow-up for another reason. Research has long established that teens who watch movies or listen to music that glamorizes drinking , drug use or violence tend to engage in those behaviors themselves. Media messages normalize early sexual experimentation and portray sex as casual, unprotected and consequence-free, encouraging sexual activity long before children are emotionally, socially or intellectually ready. Total serum cholesterol was measured in serum samples by local laboratories. The earlier a child is exposed to sexual content and begins having sex, the likelier they are to engage in high-risk sex. In one study of sex addicts, 90 percent of men and 77 percent of women reported that pornography was a factor in their addiction. If information on history of cardiovascular disease was missing, the individual was not classified and, hence, was excluded from the analyses. Populations within one country were merged and, to reduce statistical variation, some countries were also aggregated. In these analyses, data from several cohorts are pooled to reach a sufficient number of outcome events. Box , Orlando, Fla. Smoking conferred almost a doubling of the risk of stroke hazard ratio [HR], 1. Research also shows that teens who listened to music with degrading sexual references were more likely to have sex than those who had less exposure. As stated in the study protocol, 12 the main objective of the risk factor component is to assess the similarity of risk coefficients for the classic cardiovascular disease risk factors in different parts of Europe, between men and women, and between age groups using large cohorts with standardized baseline measurements and carefully validated fatal and nonfatal coronary heart disease and stroke end points. The heterogeneity was statistically significant in men but not in women. According to some studies, early exposure by age 14 to pornography and other explicit material may increase the risk of a child becoming a victim of sexual violence or acting out sexually against another child. On the other hand, blood pressure levels at baseline predicted future stroke more strongly in central Europe than in other regions; the difference was statistically significant in men.