شرکت در آزمون آنلاین انگلیسی 3 - انگلیسی 3 | آزمون شماره 11258

Heart disease is Western society’s number-one killer. It accounts for one-third of deaths in America and for well over half the deaths among middle-aged men. Heart disease was relatively rare in America at the start of the 20th century, but it has risen greatly since then, with a slight downturn since 1960. Heart disease is often viewed as a disease of modern living, spurred on by the habits and the stress of industrialized society. Evidence for this idea comes from the fact that non-Western societies have relatively lower rates of heart disease. And there is a higher rate of heart disease among immigrants to America, such as Japanese-Americans and Chinese-Americans, than among those who remain in their native country, suggesting that something about the Western environment promotes the development of the disease.

 Heart disease usually involves the formation of a fatty substance called plaque in the walls of the coronary arteries that are arteries supplying blood to the heart. If the arteries become narrowed enough or blocked, the person may suffer a heart attack (death of a region of heart muscle tissue). Among the many factors that have been found to be related to the risk of developing heart disease are high blood pressure (or hypertention), a history of heart disease among one’s close relatives (indicating a possible genetic predisposition to the disease), cigarette smoking, being relatively overweight, and a high level of a fatty substance called cholesterol in the blood.

According to the passage, when did heart disease begin to rise?