What are some possible reasons for high and rising costs of health?

The reasons may be attributed to health ailments caused by pollution, rise in life expectancy. Many people of the world are suffering from Diabetes,hypertension,various types of cancerous diseases not ever imagine some 50 years back. With advancement of medical science, people life expectancy has risen to an optimum level, leading to various old age ailments. These also contribute to high and rising costs of health.