The Normative Aging Study is a comprehensive interdisciplinary longitudinal study located in the VA Outpatient Clinic in Boston, Mass. The study was inaugurated in 1963 by the VA because of its statutory responsibility for the medical care of 25 million war veterans of whom 2 million are now 65 years of age and over, a figure which will rise to over 7 million in the next 20 years. Approximately 2,000 male veterans are enrolled for their lifetime as research subjects and undergo recurrent examinations administered on an outpatient basis The focus of the study is on non-pathological aging, so that the subjects were carefully screened in advance to satisfy rigid health criteria regardless of age. The study is distinctive because of its large N and the socioeconomic diversity of its population. Parameters include clinical medicine, biochemistry, special senses, oral medicine, anthropometry and behavior. The study is designed to investigate the relationship between normal aging and the natural history of chronic diseases. The investigation of environmental correlates of age change throughout the logitudinal design will also suggest the intrinsic or extrinsic nature of the aging process. The hybrid cross-sectional-longitudinal design will also enable the partialing of secular from true aging effects. Functional ages pertaining to various aspects of aging are being developed as a tool for assessing relative aging rates and the relationship among such differences in aging.The Normative Aging Study, an intramural research project of the Veterans Administration, began in 1963 at the VA Outpatient Clinic in Boston, Mass. The study was conceived as an interdisciplinary, longitudinal approach to the investigation of aging processes, beginning with adulthood and ending with death (Bell, Rose, & Damon, 1966). There were at the time a number of other adult longitudinal studies already underway around the country, but we saw the pressing need for combining a number of special characteristics not present in already existing studies. ROLE OF THE VETERANS ADMINISTRATIONThe VA has a special interest in aging research (Coppinger, 1967). It has broad statutory responsibility to provide medical care for 25 million war veterans whose average age is forty-five. The bulk of these are 15 million World War I1 veterans who are now approaching the age when functional decrements begin. A projection of the number of veterans sixty-five years of age and over shows a startling increase in the years ahead. At the present time, there are about 2 million veterans sixty-five years of age and over, and in the next twenty years this will skyrocket to over 7 million (see Figure l), due to the aging World War I1 veteran population (Annual Report, 1971 : 4,s). VA research is linked to patient care, therefore, the growing responsibility for care of aging veterans creates a 5

Six indexes of periodontal health were recorded in cigarette smokers, pipe/cigar smokers and nonsmokers from the Veterans Administration Dental Longitudinal Study. These indexes included calculus deposition, plaque accumulation, gingival inflammation, periodontal pocket depth, alveolar bone loss and tooth mobility. Cigarette smokers had significantly more calculus deposition than pipe/cigar smokers, although both smoker groups had more calculus than nonsmokers. Cigarette smokers accumulated slightly less plaque than pipe/cigar smokers, and both smoker groups accumulated less plaque than nonsmokers. Gingival inflammation and tooth mobility did not differ between smokers and nonsmokers, nor between the two smoker groups. Cigarette smokers had significantly greater pocket depth than nonsmokers, in contrast to pipe/cigar smokers who were not different from nonsmokers. Radiographic measurements indicated that cigarette smokers had significantly more alveolar bone loss than either pipe/cigar or nonsmokers. After covariance adjustment for age and calculus, all smokers had less plaque, gingival inflammation and tooth mobility than nonsmokers, similar periodontal pocket depth, but only cigarette smokers had greater bone loss. This finding of greater alveolar bone loss in cigarette smokers suggests a tobacco product-related effect in systemic physiologic action.