Secondary prevention activities include early detection and treatment of persons with early or asymptomatic disease, reduction in risk factors, vocational and educational counseling, and social interventions. Common approaches include periodic screening of high-risk individuals and subsequent treatment of the pathology. Secondary prevention can in many cases cure a specific pathology, but in other cases secondary prevention merely slows the progression of a pathology toward becoming a clinical condition. People with chronic diseases and those with disabling conditions can benefit significantly from secondary prevention efforts, and, as noted earlier, much of this report focuses on secondary and tertiary prevention.
Not all diseases and disabling conditions, however, can be prevented. Examples include conditions that are strongly related to the process of aging (Fries and Crapo, 1981). Aging-related conditions include arteriosclerosis, non-insulin-dependent diabetes, cancer, osteoarthritis, emphysema, and cirrhosis, as well as numerous other conditions that are less prevalent. Prevention measures are applied differently to aging-related conditions because individuals are seldom observed to be totally free of pathogenic changes. Plaque deposits in arteries, for example, can be found in most individuals, even at very young ages. Fries and Crapo (1981) argue, therefore, that it is better to think of controlling (or eliminating) risk factors to affect the progression of these conditions rather than to prevent the onset of the underlying pathological process. They maintain that primary prevention of aging-related conditions is not possible because such conditions are a part of aging and occur in all individuals. However, the rate at which such universal conditions progress can be reduced so that clinically significant symptoms can be avoided or delayed.
Thus prevention of many aging-related conditions begins with secondary prevention that aims to reduce the progression of these universal pathological processes. In some instances, although the condition may not disappear, secondary prevention is considered successful if from the standpoint of the affected individual the symptoms are not noticeable and do not require clinical treatment. In such cases the condition in essence has been prevented. What are often considered to be primary prevention activities, such as not smoking, are often secondary interventions for many aging-related, and potentially disabling, conditions because the condition has already been initiated.
Tertiary prevention strategies concentrate on arresting the progression of a condition and on preventing or limiting additional impairment, functional