“Disease often fortifies the system against the action of remedies.”
“Disorder often fortifies the system against the action of remedies.”
Which of these sentences is correct? As it happens, the first is an actual quote (H. C. Wood, 1879)1(p445) and so in that sense is the “correct” one. However, the question remains: What are the differences, if any, between disease and disorder? For that matter, where does the often-used condition fit in? While these terms are frequently used interchangeably, differences between them do exist and can assist the person wishing to use them in more specific senses.
Merriam-Webster’s Collegiate Dictionary, however, defines condition as “a usu. defective state of health,”2(p258) and the Oxford English Dictionary similarly opines that it denotes “[a] state of health, esp. one which is poor or abnormal; a malady or sickness.”
“He was full of such disease. That he may nought the deth escape” (1393).1(p445)
Disease is often used in a general sense when referring to conditions affecting a physical system (eg, cardiovascular disease) or a part of the body (eg, diseases of the foot). In this vein, Merriam-Webster’s defines disease as “a condition of the… body or one of its parts that impairs normal functioning and is typically manifested by distinguishing signs and symptoms…”2(p358); the Oxford English Dictionary defines the word similarly but particularly stresses structural change as a cause.1(p445) Dorland’s concurs with these sources but makes clear that the impaired functioning associated with the diseased state may constitute “any deviation from or interruption of the normal structure or function…” and further elaborates that “the etiology, pathology, or prognosis may be unclear or unknown.”3(p535)
“A Fever is the first disorder that affects the Blood and Vessels” (1725).1(p449)
• Condition simply indicates a state of health, whether well or ill; a condition conferring illness might be further classify as a disease or a disorder—however, condition might be use in place of disease or disorder when a value-neutral term is desire.
• Disease denotes a condition characterize by functional impairment, structural change, and the presence of specific signs and symptoms. As an aside, Dorland’s equates the terms illness and sickness with disease; while these are often use to indicate the state or experience of disease, they are also sometimes use as value-neutral alternatives for disease.
• Disorder, in contrast, denotes a condition characterize by functional impairment without structural change and, while certain disorders or categories of disorders might be accompany by specific signs and symptoms, their presence is not require for a condition to be a disorder. Like condition, disorder is sometimes use as a value-neutral term in place of disease.—Phil Sefton, ELS