Aging is damage, and therefore we should not be surprised to see that people with more obvious signs of damage are more likely to die sooner: "According to a new, long-term [study], cognitive impairment, especially at the moderate to severe stages has an impact on life expectancy similar to chronic conditions such as diabetes or chronic heart failure. Nearly 4,000 people between the ages of 60 to 102 years, initially seen from 1991 to 1993 by primary care physicians at Wishard Health Services, a large public hospital with community health centers in Indianapolis, participated in the study. The patients were followed for 13 years. ... Previous studies have associated cognitive impairment with an increased risk for death, but most of this work focused on patients with Alzheimer disease and subjects in research centers. The patients in our study better reflect the general public, displaying no indications of disease or mild, moderate or severe cognitive impairment. We found that even mild cognitive impairment, as determined by a simple screening tool in a primary care physician's office, has a strong impact on how long individuals survive on the same order as other chronic diseases." Cognitive impairment springs from physical causes linked to general health and the pace at which aging progresses in an individual, such as the state of blood vessels in the brain, for example. More damage at the level of cells and molecules leads to more evident dysfunction that we can see with our own eyes.