Disease/ja: Difference between revisions

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;Disease

:The term ''disease'' broadly refers to any condition that impairs the normal functioning of the body. For this reason, diseases are associated with the dysfunction of the body's normal [[homeostasis|homeostatic processes]]. Commonly, the term is used to refer specifically to [[infectious disease]]s, which are clinically evident diseases that result from the presence of [[pathogenic]] microbial agents, including viruses, [[bacteria]], [[Fungus|fungi]], protozoa, multicellular organisms, and aberrant proteins known as [[prion]]s. An [[infection]] or [[colony (biology)|colonization]] that does not and will not produce clinically evident impairment of normal functioning, such as the presence of the normal [[gut flora|bacteria and yeasts in the gut]], or of a [[passenger virus]], is not considered a disease. By contrast, an infection that is asymptomatic during its [[incubation period]], but expected to produce symptoms later, is usually considered a disease. [[Non-infectious disease]]s are all other diseases, including most forms of [[cancer]], [[heart disease]], and [[genetic disease]].

;Acquired disease

:An acquired disease is one that began at some point during one's lifetime, as opposed to disease that was already present at birth, which is [[congenital disorder|congenital disease]]. ''Acquired'' sounds like it could mean "caught via contagion", but it simply means acquired sometime after birth. It also sounds like it could imply secondary disease, but acquired disease can be primary disease.

;Acute disease

:An acute disease is one of a short-term nature ([[acute (medicine)|acute]]); the term sometimes also [[connotation|connotes]] a [[fulminant]] nature

;Chronic condition or chronic disease

:A [[chronic condition|chronic disease]] is one that persists over time, often characterized as at least six months but may also include illnesses that are expected to last for the entirety of one's natural life.

;Congenital disorder or congenital disease

: A [[congenital disorder]] is one that is present at [[birth]]. It is often a [[genetic disorder|genetic disease or disorder]] and can be [[heredity|inherited]]. It can also be the result of a [[vertically transmitted infection]] from the mother, such as [[HIV/AIDS]].

;Genetic disease

:A [[genetic disorder]] or disease is caused by one or more genetic [[mutation]]s. It is often inherited, but some mutations are random and [[wikt:de novo|de novo]].

;Hereditary or inherited disease

:A hereditary disease is a type of genetic disease caused by genetic mutations that are [[heredity|hereditary]] (and can run in families)

;Iatrogenic disease

:An [[Iatrogenesis|iatrogenic disease]] or condition is one that is caused by medical intervention, whether as a side effect of a treatment or as an inadvertent outcome.

;Idiopathic disease

:An [[idiopathic disease]] has an unknown cause or source. As medical science has advanced, many diseases with entirely unknown causes have had some aspects of their sources explained and therefore shed their idiopathic status. For example, when germs were discovered, it became known that they were a cause of infection, but particular germs and diseases had not been linked. In another example, it is known that [[autoimmunity]] is the cause of some forms of [[diabetes mellitus type 1]], even though the particular molecular pathways by which it works are not yet understood. It is also common to know certain factors are [[association (statistics)|associated]] with certain diseases; however, association and [[causality]] are two very different phenomena, as a third cause might be producing the disease, as well as an associated phenomenon.

;Incurable disease

:A disease that cannot be [[cure]]d. Incurable diseases are not necessarily [[terminal disease]]s, and sometimes a disease's symptoms can be treated sufficiently for the disease to have little or no impact on [[quality of life]].

;Primary disease

:A primary disease is a disease that is due to a [[root cause analysis|root cause]] of illness, as opposed to secondary disease, which is a [[sequela]], or [[complication (medicine)|complication]] that is caused by the primary disease. For example, a [[common cold]] is a primary disease, where [[rhinitis]] is a possible secondary disease, or [[sequela]]. A doctor must determine what primary disease, a cold or bacterial infection, is causing a patient's secondary [[rhinitis]] when deciding whether or not to prescribe antibiotics.

;Secondary disease

:A secondary disease is a disease that is a [[sequela]] or [[complication (medicine)|complication]] of a prior, causal disease, which is referred to as the primary disease or simply the underlying cause ([[root cause analysis|root cause]]). For example, a bacterial infection can be primary, wherein a healthy person is exposed to bacteria and becomes infected, or it can be secondary to a primary cause, that predisposes the body to infection. For example, a primary [[viral infection]] that weakens the [[immune system]] could lead to a secondary bacterial infection. Similarly, a primary [[burn]] that creates an open wound could provide an entry point for bacteria, and lead to a secondary bacterial infection.

;Terminal disease

:A terminal disease is one that is expected to have the inevitable result of death. Previously, AIDS was a terminal disease; it is now incurable, but can be managed indefinitely using medications.

;Illness

:The terms ''illness'' and ''sickness'' are both generally used as synonyms for ''disease''; however, the term ''illness'' is occasionally used to refer specifically to the patient's personal experience of his or her disease. In this model, it is possible for a person to have a disease without being ill (to have an objectively definable, but [[asymptomatic]], medical condition, such as a [[subclinical infection]], or to have a clinically apparent physical impairment but not feel sick or distressed by it), and to be ''ill'' without being ''diseased'' (such as when a person perceives a normal experience as a medical condition, or [[medicalization|medicalizes]] a non-disease situation in his or her life – for example, a person who feels unwell as a result of embarrassment, and who interprets those feelings as sickness rather than normal emotions). Symptoms of illness are often not directly the result of infection, but a collection of [[evolutionary medicine|evolved responses]] – [[sickness behavior]] by the body – that helps clear infection and promote recovery. Such aspects of illness can include [[lethargy]], [[depression (mood)|depression]], [[anorexia (symptom)|loss of appetite]], [[sleepiness]], [[hyperalgesia]], and inability to [[Attention|concentrate]].

;{{Visible anchor|Disorder}}

:A disorder is a functional abnormality or disturbance. Medical disorders can be categorized into [[mental disorder]]s, [[physical disorder]]s, [[genetic disorder]]s, [[emotional and behavioral disorders]], and [[functional disorder]]s. The term ''disorder'' is often considered more value-neutral and less stigmatizing than the terms ''disease'' or ''illness'', and therefore is preferred terminology in some circumstances. In mental health, the term ''mental disorder'' is used as a way of acknowledging the complex interaction of [[Biopsychosocial model|biological, social, and psychological factors]] in [[Psychiatry|psychiatric]] conditions; however, the term ''disorder'' is also used in many other areas of medicine, primarily to identify physical disorders that are not caused by infectious organisms, such as [[metabolic disorder]]s.

;Medical condition or health condition

:A '''medical condition''' or '''health condition''' is a broad concept that includes all diseases, [[lesion]]s, disorders, or nonpathologic condition that normally receives medical treatment, such as [[pregnancy]] or [[childbirth]]. While the term ''medical condition'' generally includes mental illnesses, in some contexts the term is used specifically to denote any illness, injury, or disease except for mental illnesses. The [[Diagnostic and Statistical Manual of Mental Disorders]] (DSM), the widely used psychiatric manual that defines all [[mental disorder]]s, uses the term ''general medical condition'' to refer to all diseases, illnesses, and injuries except for [[mental disorder]]s. This usage is also commonly seen in the psychiatric literature. Some [[health insurance]] policies also define a ''medical condition'' as any illness, injury, or disease except for psychiatric illnesses.

:As it is more [[value-neutral]] than terms like ''disease'', the term ''medical condition'' is sometimes preferred by people with health issues that they do not consider deleterious. On the other hand, by emphasizing the medical nature of the condition, this term is sometimes rejected, such as by proponents of the [[autism rights movement]].

:The term ''medical condition'' is also a synonym for ''[[medical state]]'', in which case it describes an individual patient's current state from a medical standpoint. This usage appears in statements that describe a patient as being ''in critical condition'', for example.

;{{Visible anchor|Morbidity}}

:'''Morbidity''' ({{ety|la|morbidus|sick, unhealthy}}) is a diseased state, [[disability]], or poor health due to any cause. The term may refer to the existence of any form of disease, or to the degree that the health condition affects the patient. Among severely ill patients, the level of morbidity is often measured by [[ICU scoring systems]]. [[Comorbidity]], or co-existing disease, is the simultaneous presence of two or more medical conditions, such as [[schizophrenia]] and [[substance abuse]].

:In [[epidemiology]] and [[actuarial science]], the term ''morbidity'' (also ''morbidity rate'' or ''morbidity frequency'') can refer to either the [[incidence (epidemiology)|incidence]] rate, the [[prevalence]] of a disease or medical condition, or the percentage of people who experience a given condition within a given timeframe (e.g., 20% of people will get [[influenza]] in a year). This measure of sickness is contrasted with the [[mortality rate]] of a condition, which is the proportion of people dying during a given time interval. Morbidity rates are used in actuarial professions, such as health insurance, life insurance, and long-term care insurance, to determine the correct premiums to charge to customers. Morbidity rates help insurers predict the likelihood that an insured will contract or develop any number of specified diseases.

; Pathosis or pathology

:''Pathosis'' (plural ''pathoses'') is synonymous with ''disease''. The word ''[[pathology]]'' also has this [[word sense|sense]], in which it is commonly used by physicians in the [[medical literature]], although [[wikt:pathology#Usage notes|some editors prefer to reserve ''pathology'' to its other senses]]. Sometimes a slight [[connotation|connotative]] shade causes preference for ''pathology'' or ''pathosis'' implying "some [as yet poorly analyzed] [[pathophysiology|pathophysiologic process]]" rather than ''disease'' implying "a specific disease entity as defined by diagnostic criteria being already met". This is hard to quantify [[denotation|denotatively]], but it explains why [[cognitive synonymy]] is not invariable.

;Syndrome

:A [[syndrome]] is the association of several [[signs and symptoms]], or other characteristics that often occur together, regardless of whether the cause is known. Some syndromes such as [[Down syndrome]] are known to have only one cause (an extra [[chromosome]] at birth). Others such as [[Parkinsonian syndrome]] are known to have multiple possible causes. [[Acute coronary syndrome]], for example, is not a single disease itself but is rather the manifestation of any of several diseases including [[myocardial infarction]] secondary to [[coronary artery disease]]. In yet other syndromes, however, the [[idiopathy|cause is unknown]]. A familiar syndrome name often remains in use even after an underlying cause has been found or when there are a number of different possible primary causes. Examples of the first-mentioned type are that [[Turner syndrome]] and [[DiGeorge syndrome]] are still often called by the "syndrome" name despite that they can also be viewed as disease entities and not solely as sets of signs and symptoms.

;Predisease

:{{anchor|Predisease}}'''Predisease''' is a [[subclinical]] or [[prodrome|prodromal]] vanguard of a disease. [[Prediabetes]] and [[prehypertension]] are common examples. The [[nosology]] or epistemology of predisease is contentious, though, because there is seldom a [[bright line]] differentiating a legitimate concern for subclinical/prodromal/premonitory status (on one hand) and [[conflict of interest]]–driven [[disease mongering]] or [[medicalization]] (on the other hand). Identifying legitimate predisease can result in useful preventive measures, such as motivating the person to get a healthy amount of physical exercise, but labeling a healthy person with an unfounded notion of predisease can result in [[overtreatment]], such as taking drugs that only help people with severe disease or paying for drug prescription instances whose [[benefit–cost ratio]] is minuscule (placing it in the waste category of [[Centers for Medicare and Medicaid Services|CMS]]' "waste, fraud, and abuse" classification). Three requirements for the legitimacy of calling a condition a predisease are:

:* a truly high risk for progression to disease – for example, a [[Precancerous condition|pre-cancer]] will almost certainly turn into cancer over time

:* actionability for risk reduction – for example, removal of the precancerous tissue prevents it from turning into a potentially deadly cancer