comorbidity comorbidity in medicine, comorbidity - from latin morbus ("sickness"), co ("together"), -ity (as if - several sicknesses together) - is the presence of one or more additional conditions often co-occurring (that is, concomitant or concurrent) with a primary condition. comorbidity describes the effect of all other conditions an individual patient might have other than the primary condition of interest, and can be physiological or psychological. in the context of mental health, comorbidity often refers to disorders that are often coexistent with each other, such as depression and anxiety disorders. the concept of multimorbidity is related to comorbidity but presents a different meaning and approach. definition the term "comorbid" has three definitions: to indicate a medical condition existing simultaneously but independently with another condition in a patient. to indicate a medical condition in a patient that causes, is caused by, or is otherwise related to another condition in the same patient. to indicate two or more medical conditions existing simultaneously regardless of their causal relationship. comorbidity can indicate either a condition existing simultaneously, but independently with another condition or a related derivative medical condition. the latter sense of the term causes some overlap with the concept of complications. for example, in longstanding diabetes mellitus, the extent to which coronary artery disease is an independent comorbidity versus a diabetic complication is not easy to measure, because both diseases are quite multivariate and there are likely aspects of both simultaneity and consequence. the same is true of intercurrent diseases in pregnancy. in other examples, the true independence or relation is not ascertainable because syndromes and associations are often identified long before pathogenetic commonalities are confirmed (and, in some examples, before they are even hypothesized). in psychiatric diagnoses it has been argued in part that this "'use of imprecise language may lead to correspondingly imprecise thinking', this usage of the term 'comorbidity' should probably be avoided." however, in many medical examples, such as comorbid diabetes mellitus and coronary artery disease, it makes little difference which word is used, as long as the medical complexity is duly recognized and addressed. difference from multimorbidity comorbidity is often referred to as multimorbidity even though the two are considered distinct clinical scenarios. comorbidity means that one 'index' condition is the focus of attention, and others are viewed in relation to this. in contrast, multimorbidity describes someone having two or more long-term (chronic) conditions without any of them holding priority over the others. this distinction is important in how the healthcare system treats people and helps making clear the specific settings in which the use of one or the other term can be preferred. multimorbidity offers a more general and person-centered concept that allows focusing on all of the patient's symptoms and providing a more holistic care. in other settings, for example in pharmaceutical research, comorbidity might often be the more useful term to use. mental health in psychiatry, psychology, and mental health counseling, comorbidity refers to the presence of more than one diagnosis occurring in an individual at the same time. however, in psychiatric classification, comorbidity does not necessarily imply the presence of multiple diseases, but instead can reflect current inability to supply a single diagnosis accounting for all symptoms. on the dsm axis i, major depressive disorder is a very common comorbid disorder. the axis ii personality disorders are often criticized because their comorbidity rates are excessively high, approaching 60% in some cases. critics assert this indicates these categories of mental illness are too imprecisely distinguished to be usefully valid for diagnostic purposes, impacting treatment and resource allocation. symptom overlap is a key component against dsm classification and serves as a note towards redefining criteria in disorders that the root cause may not be understood thoroughly. regardless of criticisms, it stands that, annually, up to 45% of mental health patients fit the criteria for a comorbid diagnosis. a comorbid diagnosis is associated with more severe symptomatic expression and greater chance of dismal prognosis. certain diagnoses such as adhd, autism, ocd, and mood disorders have higher rates of co-occurring or being prevalent in separate diagnoses. "comorbidity in ocd is the rule rather than the exception" with ocd diagnoses facing a lifetime rate of 90%. with overlapping symptoms comes overlap in treatment as well, cbt for example is common for both adhd and ocd with pediatric onset and can be effective for both in a comorbid diagnosis. ocd and eating disorders have a high rate of occurrence, it is estimated that 20-60% of patients with an eating disorder have ocd. more often, comorbidity complicates and can prevent treatment efficacy on a varying scale depending on the circumstances. the term 'comorbidity' was introduced in medicine by feinstein (1970) to describe cases in which a 'distinct additional clinical entity' occurred before or during treatment for the 'index disease', the original or primary diagnosis. since the terms were coined, meta studies have shown that criteria used to determine the index disease were flawed and subjective, and moreover, trying to identify an index disease as the cause of the others can be counterproductive to understanding and treating interdependent conditions. in response, 'multimorbidity' was introduced to describe concurrent conditions without relativity to or implied dependency on another disease, so that the complex interactions to emerge naturally under analysis of the system as a whole. although the term 'comorbidity' has recently become very fashionable in psychiatry, its use to indicate the concomitance of two or more psychiatric diagnoses is said to be incorrect because in most cases it is unclear whether the concomitant diagnoses actually reflect the presence of distinct clinical entities or refer to multiple manifestations of a single clinical entity. it has been argued that because "'the use of imprecise language may lead to correspondingly imprecise thinking', this usage of the term 'comorbidity' should probably be avoided". due to its artifactual nature, psychiatric comorbidity has been considered as a kuhnian anomaly leading the dsm to a scientific crisis and a comprehensive review on the matter considers comorbidity as an epistemological challenge to modern psychiatry. the hierarchical taxonomy of psychopathology is a leading alternative classification system that addresses these concerns about comorbidity. history widespread study of physical and mental pathology found its place in psychiatry. i. jensen (1975), j.h. boyd (1984), w.c. sanderson (1990), yuri nuller (1993), d.l. robins (1994), a. b. smulevich (1997), c.r. cloninger (2002) and other psychiatrists discovered a number of comorbid conditions in those with psychiatric disorders. the influence of comorbidity on the clinical progression of the primary (basic) physical disorder, effectiveness of the medicinal therapy and immediate and long-term prognosis of the patients was researched by physicians and scientists of various medical fields in many countries across the globe. these scientists and physicians included: m. h. kaplan (1974), t. pincus (1986), m. e. charlson (1987), f. g. schellevis (1993), h. c. kraemer (1995), m. van den akker (1996), a. grimby (1997), s. greenfield (1999), m. fortin (2004) & a. vanasse (2004), c. hudon (2005), l. b. lazebnik (2005), a. l. vertkin (2008), g. e. caughey (2008), f. i. belyalov (2009), l. a. luchikhin (2010) and many others. inception of the term many centuries ago the doctors propagated the viability of a complex approach in the diagnosis of disease and the treatment of the patient, however, modern medicine, which boasts a wide range of diagnostic methods and a variety of therapeutic procedures, stresses specification. this brought up a question: how to wholly evaluate the state of a patient who has a number of diseases simultaneously, where to start from and which disease(s) require(s) primary and subsequent treatment? for many years this question stood out unanswered, until 1970, when a renowned american doctor epidemiologist and researcher, a.r. feinstein, who had greatly influenced the methods of clinical diagnosis and particularly methods used in the field of clinical epidemiology, came out with the term of "comorbidity". the appearance of comorbidity was demonstrated by feinstein using the example of patients physically affected by rheumatic fever, discovering the worst state of the patients, who simultaneously had multiple diseases. in due course of time after its discovery, comorbidity was distinguished as a separate scientific-research discipline in many branches of medicine. evolution of the term presently there is no agreed-upon terminology of comorbidity. some authors bring forward different meanings of comorbidity and multi-morbidity, defining the former, as the presence of a number of diseases in a patient, connected to each other through proven pathogenetic mechanisms and the latter, as the presence of a number of diseases in a patient, not having any connection to each other through any of the proven to date pathogenetic mechanisms. others affirm that multi-morbidity is the combination of a number of chronic or acute diseases and clinical symptoms in a person and do not stress the similarities or differences in their pathogenesis. however the principle clarification of the term was given by h. c. kraemer and m. van den akker, determining comorbidity as the combination in a patient of 2 or more chronic diseases (disorders), pathogenetically related to each other or coexisting in a single patient independent of each disease's activity in the patient. synonyms polymorbidity multifactorial diseases polypathy dual diagnosis, used for mental health issues pluralpathology epidemiology comorbidity is widespread among the patients admitted at multidiscipline hospitals. during the phase of initial medical help, the patients having multiple diseases simultaneously are a norm rather than an exception. prevention and treatment of chronic diseases declared by the world health organization, as a priority project for the second decade of the 20th century, are meant to better the quality of the global population. this is the reason for an overall tendency of large-scale epidemiological researches in different medical fields, carried-out using serious statistical data. in most of the carried-out, randomized, clinical researches the authors study patients with single refined pathology, making comorbidity an exclusive criterion. this is why it is hard to relate researches, directed towards the evaluation of the combination of ones or the other separate disorders, to works regarding the sole research of comorbidity. the absence of a single scientific approach to the evaluation of comorbidity leads to omissions in clinical practice. it is hard not to notice the absence of comorbidity in the taxonomy (systematics) of disease, presented in icd-10. clinico-pathological comparisons all the fundamental researches of medical documentation, directed towards the study of the spread of comorbidity and influence of its structure, were conducted until the 1990s. the sources of information, used by the researchers and scientists, working on the matter of comorbidity, were case histories, hospital records of patients and other medical documentation, kept by family doctors, insurance companies and even in the archives of patients in old houses. the listed methods of obtaining medical information are mainly based on clinical experience and qualification of the physicians, carrying out clinically, instrumentally and laboratorially confirmed diagnosis. this is why despite their competence, they are highly subjective. no analysis of the results of postmortem of deceased patients was carried out for any of the comorbidity researches. "it is the duty of the doctor to carry out autopsy of the patients they treat", said once professor m. y. mudrov. autopsy allows you to exactly determine the structure of comorbidity and the direct cause of death of each patient independent of his/her age, gender and gender specific characteristics. statistical data of comorbid pathology, based on these sections, are mainly devoid of subjectivism. research the analysis of a decade long australian research based on the study of patients having 6 widespread chronic diseases demonstrated that nearly half of the elderly patients with arthritis also had hypertension, 20% had cardiac disorders and 14% had type 2 diabetes. more than 60% of asthmatic patients complained of concurrent arthritis, 20% complained of cardiac problems and 16% had type 2 diabetes. in patients with chronic kidney disease (renal insufficiency) the frequency of coronary heart disease is 22% higher and new coronary events 3.4 times higher compared to patients without kidney function disorders. progression of ckd towards end stage renal disease requiring renal replacement therapy is accompanied by increasing prevalence of coronary heart disease and sudden death from cardiac arrest. a canadian research conducted upon 483 obesity patients, it was determined that spread of obesity related accompanying diseases was higher among females than males. the researchers discovered that nearly 75% of obesity patients had accompanying