Scientists from Europe and Canada found that the correlation between the presence of depressive symptoms, cardiovascular disease and all-cause mortality fair for residents of countries with different levels of economic development. The survey of scientists was attended by almost 146 thousand residents of 21 countries: participants with at least four symptoms of depression in 14 percent more often diagnosed with cardiovascular disease, and the level of premature death from all causes was higher by 17 percent. The relationship between depression symptoms, cardiovascular disease and mortality was more pronounced in urban areas than in rural, write scientists in JAMA Psychiatry.
Large population studies will allow us to discover correlations between exposure to any risk factor and how widely distributed in the population of a certain disorder, disease or condition: as a result, we can conclude that two (or more) of these variables are interconnected, and based on this recommendations for preventive therapy. The quality of such studies depends on the size and diversity of the sample: large sample allow not only to increase statistical power, but also significantly to take into account all the side variables. This allows you to avoid situations in which the risk of developing the disease affects not considered variable, and, for example, socioeconomic status.
However, even the largest population-based studies do not possess absolute external validity because their results are valid only for the studied population. It is therefore very important studies involving volunteers from different countries, preferably with different levels of economic development.
Scott Lear (Scott Lear) from the canadian Simon Fraser University and his colleagues in the 14 years collecting information about 145862 the inhabitants of the 21 countries with different levels of GDP per capita in the sample were residents, for example, Bangladesh, China, Brazil, Turkey, Sweden, Canada, Malaysia and Poland (Russia and the US not). All participants fell into the age category from 35 to 70 years: for every available information about the presence of depressive symptoms (sadness, depressed, suicidal thoughts, loss of interest, and other) collected at baseline, and information on the occurrence of cardiovascular disease and mortality in the future. All additional data like sex, age, tobacco and alcohol consumption, as well as the presence of chronic disease was also considered in the analysis.
Scientists have found that in the presence of at least four depressive symptoms, cardiovascular diseases were diagnosed in 14 percent more likely, and mortality from all causes was higher than 17 percent, while the risk increased with increasing number of symptoms. Interestingly, a similar Association was observed in all studied countries and, apparently, did not depend on GDP per capita; and cardiovascular disease, and mortality from all causes was higher in urban areas than in rural (23 percent versus 10 percent for joint risk).
Despite the fact that the presence of depressive symptoms is not always clearly indicates the presence of depression, presence of at least four of the seven used in the study of symptoms usually indicates a high likelihood of developing depression. The authors noted that the symptoms of the disorder should be considered as a separate and important risk factor, and in countries with different income, and especially among the urban population.
By the way, residents of cities and rural areas compare quite often: the different levels and lifestyle often leads to the fact that the indicators of the health of the citizens and villagers differ. However, a study published last year showedthat rural residents get fat almost faster citizens — at least in the last 30 years.