"While successful aging has been defined in many ways, we focused on individuals who had reached at least 90 without significant decline in mental capacity," said lead researcher George S. Zubenko, MD, PhD, Professor of Psychiatry and Biological Sciences at the University of Pittsburgh School of Medicine. "Not only is this a goal that many of us share, this definition of 'successful aging' can be determined objectively and consistently across subjects--an important requirement of scientific studies."
While previous research found that genes make important contributions to exceptional longevity, the goal of this study was to identify regions of the human genome that contributed, along with lifestyle factors, to reaching age 90 with preserved cognition.
The study involved 100 people age 90 and older with preserved cognition, as measured by clinical and psychometric assessments. Half of the subjects were male, half were female. Using a novel genome survey method, scientists compared the DNA of the study sample with that of 100 young adults, aged 18-25 years old, who were matched for sex, race, ethnicity and geographic location. Specifically, Dr. Zubenko and his research team attempted to identify specific genetic sequences present in older individuals that may be linked to reaching older ages with preserved cognitive abilities, or conversely, specific genetic sequences present in younger individuals (and not present in those over age 90) that may impede successful aging. The study also looked at a variety of lifestyle factors, such as smoking and alcohol consumption, with t