The Definition And Concept Of Health

Health is sometimes negatively defined as the absence of disease and injury, sometimes as a normative judgment referring to the average state of most people, and sometimes as a positive concept of well-being. This report uses “health” with the meaning of “positive health”. Although disease is commonly regarded as either present or absent, most health problems fall on a continuum. Changing diagnostic thresholds — such as reducing the body mass index guide for overweight from 28 to 25 — can abruptly change the health status for large numbers of people. Furthermore, current wellness or illness must be considered together with prospects for the future.

The concept of “positive health”, while controversial, derives from evidence that attitudes and behaviors enhance the body’s resistance to and recovery from disease, illness, and surgical intervention. Disability and illness can be distinct from health or, together with health, represent different points on a continuum Patrick and Erickson (1993). The various definitions of health, each emphasizing different concepts, have been debated for centuries. Precise biomedical or biological definitions (absence of abnormal biological markers or physiological abnormalities) are useful because they offer opportunities for precise measurement, but they fail to capture all the attributes typically associated with health. On the other hand, the broad definition adopted by the World Health Organization in 1948 (“Health is a state of complete physical, mental, and social well-being and not merely the absence of infirmity”) is comprehensive but difficult to apply. Common epidemiologic measures, which emphasize morbidity and mortality, are incomplete. Morbidity data, for example, often omit information about mortality; mortality data typically do not include information about concurrent morbidity. Disease and disability affect multiple aspects of wellness. A comprehensive definition of health requires integration of broader concepts of morbidity and mortality.

From a medical perspective, people are healthy if they are uninjured and free of disease, but a person with risk factors for disease might be considered unhealthy. As increasing numbers of people are screened or as technology improves, more disease is revealed Black and Welch (1997). New technologies might identify “diseases” that have little effect on life expectancy or quality of life. Pathology thus depends on the state of biomedical knowledge and technology. Despite the appeal of the medical model, however, it can provide evidence that is in conflict with other indicators of health. The health care system defines the need for health care based on the technology available for assessment and treatment. But, when a patient feels distress, health care needs do not always correlate with health care system definitions Evans and Stoddard (1990). Although disease usually is regarded as a binary variable — it is either present or absent — most health problems fall on a continuum. Changing the thresholds associated with a disease can thus change the number of people who would be considered sick. For example, in the past, “overweight” was defined as a body mass index greater than 28. When that threshold recently was reset at 25 NHLBI (1998), most of the adult U. S. population became classified as overweight. Similarly, new methods for assessing subthreshold depression greatly increased the number of people characterized as having that condition Judd et al. , (1996). Although slightly more than 5% of patients in general medical practice qualify for a diagnosis of depression, as defined by the American Psychiatric Association in its DSM-IV APA (1994), more than 25% meet the criteria for “subsyndromal” depression Wells (1996).

An alternative to the traditional biomedical model, the “outcomes model, ” emphasizes patient outcomes rather than disease pathologies. The biomedical model is predicated on finding specific biological problems; the outcomes model considers consequences from the perspective of the patient. Successful treatments improve quality of life or extend length of life. This might differ significantly from what would be considered successful treatment using strictly biomedical measures. One review Fowler et al. , (1994), for example, found that although many surgical procedures have no effect on life expectancy, they can help relieve symptoms and improve functional status. Outcomes assessment is useful to determine whether symptoms are, in fact, relieved. A growing body of work demonstrates that measures of wellness are significant predictors of longevity for patients with chronic illnesses.

Typically, simple self-report measures of overall health status perform at least as well as physiological indicators do. Contemporary definitions recognize that health is multidimensional. Spilker (1996) identified five major domains of life quality: physical status and functional ability, psychological status and well-being, social interactions, economic and vocational status and factors, and religious and spiritual status. Various health outcomes approaches assess different dimensions, and the dimensions themselves vary considerably in approach.

An emerging consensus suggests that the concept of health must integrate mortality with multiple dimensions of life quality. Most attempts include physical and mental symptoms of behavioral and social functioning. Symptoms could be as various as pain, cough, anxiety, or depressed mood. Physical functioning is typically measured by limited mobility or by confinement to bed or home. Social functioning is indicated by performance of usual social roles such as attendance at school, ability to work, or participation in recreational activities. The concept of health-related quality of life incorporates combinations of these attributes.