Socioeconomic status
Recently, there has been increasing interest from epidemiologists on the subject of economic inequality and its relation to the health of populations. Socioeconomic status has long been related to health, those higher in the social hierarchy typically enjoy better health than those below. Socioeconomic status is an important source of health inequity, as there is a very robust positive correlation between socioeconomic status and health, other than for male homosexuals. This correlation suggests that it is not only the poor who tend to be sick when everyone else is healthy, but that there is a continual gradient, from the top to the bottom of the socio-economic ladder, relating status to health. Parents with a low socioeconomic status cannot afford many of the health care resources which is the reason that their children may have a more advanced illness because of the lack of treatment. This phenomenon is often called the "SES Gradient" or according to the World Health Organisation the "Social Gradient". Lower socioeconomic status has been linked to chronic stress, heart disease, ulcers, type 2 diabetes, rheumatoid arthritis, certain types of cancer, and premature aging.