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- •Preface
- •Contents
- •Notes on Contributors
- •List of Figures
- •1.1 What Is Comorbidity?
- •1.2 Why Is Comorbidity Important?
- •1.3 What Is the Cost of Comorbidity?
- •References
- •2 Models of Comorbidity
- •References
- •References
- •Endocrine System
- •References
- •5 Comorbid Eating Disorders
- •5.1 Anorexia Nervosa and Bulimia Nervosa
- •References
- •6 Comorbid Psychiatric Illnesses
- •6.4.1 Psychological Models
- •6.4.2 Biological Models
- •6.4.3 Integrated Models of Depression Causation
- •References
- •References
- •8.1 Methodological Approaches
- •8.1.1 Removal of Overlapping Scale Items
- •8.1.2 Longitudinal and Experimental Studies
- •8.2 Statistical Approaches
- •8.3 Overlapping Risk and Protective Factors
- •8.5 Summary
- •References
- •9 Typing It All Together
- •9.1 What Causes Comorbidity?
- •9.2 Comorbidity—Where to from Here?
- •References

1 Comorbidity: What Is It and Why Is It Important? 17
than patients with a normal body mass index. Archives of Internal Medicine
& Health. 2005;165(1):25–30. https://doi.org/10.1001/archinte.165.1.25.
17. Yeh S-SS, Brown RF. Disordered eating partly mediates the relationship
between poor sleep quality and high body mass index. Eating Behaviors.
2014;15(2):291–297. https://doi.org/10.1016/j.eatbeh.2014.03.014.
18. Dixon JB, Schachter LM, O’Brien PE. Sleep disturbance and obesity:
Changes following surgically induced weight loss. Archives of Internal
Medicine. 2001;161(1):102–106. https://doi.org/10.1001/archinte.161.1.
102.
19. Borsboom D, Cramer AOJ, SchmittmannVD, EpskampS, Waldorp LJ.The
small world of psychopathology.PLOSOne. 2011;6(11):e27407.https://doi.
org/10.1371/journal.pone.0027407.
20. García-Olmos L, Salvador CH, Alberquilla Á, et al. Comorbidity pat-
terns in patients with chronic diseases in general practice. PLOS One.
2012;7(2):e32141. https://doi.org/10.1371/journal.pone.0032141.
21. Britt HC, Harrison CM, Miller GC, Knox SA. Prevalence and patterns of
multimorbidity in Australia. Medical Journal of Australia. 2008;189(2):72–
77. https://doi.org/10.5694/j.1326-5377.2008.tb01919.x.
22. van den Akker M, Buntinx F, Roos S, Knottnerus JA. Problems in deter-
mining occurrence rates of multimorbidity. Journal of Clinical Epidemiology.
2001;54(7):675–679. https://doi.org/10.1016/s0895-4356(00)00358-9.
23. Loza E, Jover JA, Rodriguez L, Carmona L, Group ES. Multimorbid-
ity: Prevalence, effect on quality of life and daily functioning, and varia-
tion of this effect when one condition is a rheumatic disease. Seminars in
Arthritis and Rheumatism. 2009;38(4):312–319. https://doi.org/10.1016/j.
semarthrit.2008.01.004.
24. U. S. Department of Health & Human Services. Multiple chronic condi-
tions—A strategic framework: Optimumhealth and quality of life for individuals
with multiple chronic conditions. Washington, D.C., December 2010.
25. Global Burden of Disease Study 2013 Collaborators. Global, regional,
and national incidence, prevalence, and years lived with disability for
301 acute and chronic diseases and injuries in 188 countries, 1990–
2013: A systematic analysis for the Global Burden of Disease Study
2013. The Lancet. 2015;386(9995):743–800. https://doi.org/10.1016/
s0140-6736(15)60692-4.
26. Carmona M, García-Olmos LM, Alberquilla A, et al. Heart failure in the
family practice: A study of the prevalence and co-morbidity. Family Practice.
2010;28(2):128–133. https://doi.org/10.1093/fampra/cmq084.

18 R. Brown and E. Thorsteinsson
27. Starfield B, Lemke KW, Bernhardt T, Foldes SS, Forrest CB, Weiner JP.
Comorbidity: Implications for the importance of primary care in ‘case’ man-
agement. The Annals of Family Medicine. 2003;1(1):8–14. https://doi.org/
10.1370/afm.1.
28. Ferrari AJ, Charlson FJ, Norman RE, et al. Burden of depressive disorders
by country, sex, age, and y: Findings from the Global Burden of Disease
Study 2010. PLOS Medicine. 2013;10(11):e1001547. https://doi.org/10.
1371/journal.pmed.1001547.
29. Whiteford HA, Degenhardt L, Rehm J, et al. Global burden of disease
attributable to mental and substance use disorders: Findings from the Global
Burden of Disease Study 2010. The Lancet. 2013;382(9904):1575–1586.
https://doi.org/10.1016/s0140-6736(13)61611-6.
30. Naylor C, Parsonage M, McDaid D, Knapp M, Fossey M, Galea A. Long-
term conditions and mental health: The cost of co-morbidities. London, UK:
The King’s Fund; 2012.
31. Australian Bureau of Statistics. Disability, ageing and carers, Australia: Sum-
mary of findings, 2012. Canberra, Australia: Author; 2013. 4430.0.
32. White CA. Cognitive behavioral principles in managing chronic disease.
Western Journal of Medicine. 2001;175(5):338–342.
33. Brown RF, Valpiani EM, Tennant CC, et al. Longitudinal assessment of
anxiety, depression and fatigue in people with multiple sclerosis. Psychology
& Psychotherapy: Theory, Research & Practice. 2009;82:41–56. https://doi.
org/10.1348/147608308x345614.
34. Jansson-FröjmarkM, Lindblom K. A bidirectionalrelationship betweenanx-
iety and depression, and insomnia? A prospective study in the general pop-
ulation. Journal of Psychosomatic Research. 2008;64(4):443–449. https://doi.
org/10.1016/j.jpsychores.2007.10.016.
35. Valpiani EM, Brown RF, Thorsteinsson EB, Hine DW. Poor sleep qual-
ity mediates between depression to fatigue in a university student sample.
Psychology and Education. 2011;48(1&2):59–71.
36. Sartorious N. Comorbidity of mental and physical diseases: A main chal-
lenge for medicine of the 21st century. Shanghai Archives of Psychia-
try. 2013;25(2):68–69. https://doi.org/10.3969/j.issn.1002-0829.2013.02.
002.
37. Cuijpers P, Berking M, Andersson G, Quigley L, Kleiboer A, Dobson KS.
A meta-analysis of cognitive-behavioural therapy for adult depression, alone
and incomparison with othertreatments. The Canadian Journal of Psychiatry.
2013;58(7):376–385. https://doi.org/10.1177/070674371305800702.

1 Comorbidity: What Is It and Why Is It Important? 19
38. Malouff JM, Thorsteinsson EB, Rooke SE, Bhullar N, Schutte NS. Effi-
cacy of cognitive behavioral therapy for chronic fatigue syndrome: A meta-
analysis. Clinical Psychology Review. 2008;28(5):736–745. https://doi.org/
10.1016/j.cpr.2007.10.004.
39. Okajima I, Komada Y, Inoue Y. A meta-analysis on the treatment effective-
ness of cognitive behavioral therapy for primary insomnia. Sleep and Biologi-
cal Rhythms. 2011;9(1):24–34. https://doi.org/10.1111/j.1479-8425.2010.
00481.x.
40. Linardon J, Wade TD, de la Piedad Garcia X, Brennan L. The effi-
cacy of cognitive-behavioral therapy for eating disorders: A systematic
review and meta-analysis. Journal of Consulting and Clinical Psychology.
2017;85(11):1080–1094. https://doi.org/10.1037/ccp0000245.
41. Buscemi N, Vandermeer B, Friesen C, et al. The efficacy and safety of drug
treatments for chronic insomnia in adults: A meta-analysis of RCTs. Jour-
nal of General Internal Medicine. 2007;22(9):1335. https://doi.org/10.1007/
s11606-007-0251-z.
42. Zammit GK. Antidepressants and insomnia. Primary Psychiatry.
2008;15(5):61–69.
43. Everitt H, Baldwin DS, Stuart B, et al. Antidepressants for insomnia in
adults. Cochrane Database of Systematic Reviews. 2018(5). https://doi.org/
10.1002/14651858.cd010753.pub2.
44. McDaid D, Park A-L. Counting all the costs: The economic impact of
comorbidity. In: Sartorius N, Holt RIG, Maj M, eds. Comorbidity of mental
and physical disorders. Key issues mental health. Vol. 179. Basel, Switzerland:
Karger; 2015:23–32.
45. Cortaredona S, Ventelou B. The extra cost of comorbidity: Multiple illnesses
and the economic burden of non-communicable diseases. BMC Medicine.
2017;15(1):216. https://doi.org/10.1186/s12916-017-0978-2.
46. The Royal Australian & New Zealand College of Psychiatrists. The economic
cost of serious mental illness and comorbidities in Australia and New Zealand.
Melbourne, Australia: Royal Australian and New Zealand College of Psychi-
atrists (RANZCP); 2016.
47. Vigo D,Thornicroft G, AtunR. Estimating the true global burden of mental
illness. The Lancet Psychiatry. 2016;3(2):171–178. https://doi.org/10.1016/
s2215-0366(15)00505-2.
48. Sayers SL, Hanrahan N, Kutney A, Clarke SP, Reis BF, Riegel B. Psychiatric
comorbidity andgreater hospitalization risk, longer lengthof stay, and higher
hospitalization costs in older adults with heart failure. Journal of the American

20 R. Brown and E. Thorsteinsson
GeriatricsSociety.2007;55(10):1585–1591. https://doi.org/10.1111/j.1532-
5415.2007.01368.x.
49. Hillman DR, Lack LC. Public healthimplications of sleep loss:The commu-
nity burden. MJA. 2013;199(8):S7–S10. https://doi.org/10.5694/mja13.
10620.
50. Rosekind MR, Gregory KB, Mallis MM, Brandt SL, Seal B, Lerner D. The
cost of poor sleep: Workplace productivity loss and associated costs. Journal
of Occupationaland Environmental Medicine. 2010;52(1):91–98.https://doi.
org/10.1097/jom.0b013e3181c78c30.
51. Deloitte Access Economics. Re-awakening Australia.The economic cost of sleep
disorders in Australia, 2010. Sleep Health Foundation; October 2011.
52. Zochil ML, Thorsteinsson EB. Exploring poor sleep, mental health, and
help-seeking intentionin universitystudents. AustralianJournal of Psychology.
2018;70(1):41–47. https://doi.org/10.1111/ajpy.12160.
53. Morales-Espinoza EM, Kostov B, Salami DC, et al. Complexity, comor-
bidity, and health care costs associated with chronic widespread pain in
primary care. Pain. 2016;157(4):818–826. https://doi.org/10.1097/j.pain.
0000000000000440.
54. Hippisley-Cox J, Fielding K, Pringle M. Depression as a risk fac-
tor for ischaemic heart disease in men: Population based case-control
study. BMJ. 1998;316(7146):1714–1719. https://doi.org/10.1136/bmj.
316.7146.1714.
55. Pi-Sunyer X. The medical risks of obesity. Postgraduate Medicine.
2009;121(6):21–33. https://doi.org/10.3810/pgm.2009.11.2074.
56. Katon WJ, Rutter C, Simon G, et al. The association of comorbid
depression with mortality in patients with type 2 diabetes. Diabetes Care.
2005;28(11):2668–2672. https://doi.org/10.2337/diacare.28.11.2668.
57. Lin EH, Heckbert SR, Rutter CM, et al. Depression and increased mortality
in diabetes: Unexpected causes of death. The Annals of Family Medicine.
2009;7(5):414–421. https://doi.org/10.1370/afm.998.
58. Gallicchio L, Kalesan B. Sleep duration and mortality: A systematic review
and meta-analysis. Journal of Sleep Research. 2009;18(2):148–158. https://
doi.org/10.1111/j.1365-2869.2008.00732.x.
59. Wang X, Ouyang Y, Wang Z, Zhao G, Liu L, Bi Y. Obstructive sleep
apnea and risk of cardiovascular disease and all-cause mortality: A meta-
analysis of prospective cohort studies. International Journal of Cardiology.
2013;169(3):207–214. https://doi.org/10.1016/j.ijcard.2013.08.088.

1 Comorbidity: What Is It and Why Is It Important? 21
60. Fonseca MI, Pereira T, Caseiro P. Death and disability in patients with sleep
apnea—A meta-analysis. Brazilian Archives of Cardiology. 2015;104(1):58–
66. https://doi.org/10.5935/abc.20140172.
61. Arcelus J, Mitchell AJ, Wales J, Nielsen S. Mortality rates in patients with
anorexia nervosa and other eating disorders: A meta-analysis of 36 stud-
ies. Archives of General Psychiatry. 2011;68(7):724–731. https://doi.org/10.
1001/archgenpsychiatry.2011.74.
62. Ejaz SM, Khawaja IS, Bhatia S, Hurwitz TD. Obstructive sleep apnea and
depression: A review. Innovations in Clinical Neuroscience. 2011;8(8):17–25.
63. Crump C, Winkleby MA, Sundquist K, Sundquist J. Comorbidities and
mortality in persons with schizophrenia: A Swedish national cohort study.
American Journal of Psychiatry. 2013;170(3):324–333. https://doi.org/10.
1176/appi.ajp.2012.12050599.
64. Saha S, Chant D, McGrath J.A systematic review ofmortality in schizophre-
nia: Is the differential mortality gap worsening over time? Archives of Gen-
eral Psychiatry. 2007;64(10):1123–1131. https://doi.org/10.1001/archpsyc.
64.10.1123.
65. Zivin K, Yosef M, Miller EM, et al. Associations between depression and
all-cause and cause-specific risk of death: A retrospective cohort study
in the Veterans Health Administration. Journal of Psychosomatic Research.
2015;78(4):324–331. https://doi.org/10.1016/j.jpsychores.2015.01.014.
66. PedersonJL, Warkentin LM, Majumdar SR, McAlister FA.Depressive symp-
toms are associated with higher rates of readmission or mortality after medi-
cal hospitalization: A systematic review andmeta-analysis. Journal of Hospital
Medicine. 2016;11(5):373–380. https://doi.org/10.1002/jhm.2547.
67. World Health Organization. International classification of functioning, dis-
ability and health: ICF. Geneva, Switzerland: World Health Organization;
2001.
68. Honan CA, Brown RF, Hine DW, et al. The multiple sclerosis work difficul-
ties questionnaire. Multiple Sclerosis Journal. 2012;18(6):871–880. https://
doi.org/10.1177/1352458511431724.
69. Australian Human Rights Commission. Willing to work: National inquiry
into employment discrimination against older Australians and Australians
with disability; 2015. https://www.humanrights.gov.au/sites/default/files/
document/publication/discussion-paper-disability.pdf. Accessed 3 Novem-
ber 2015.

22 R. Brown and E. Thorsteinsson
70. Scott K, Von Korff M, Alonso J, et al. Mental–physical co-morbidity and its
relationship with disability: Results from the World Mental Health Sur-
veys. Psychological Medicine. 2009;39(1):33–43. https://doi.org/10.1017/
s0033291708003188.
71. Schoevers RA, Deeg D, Van Tilburg W, Beekman A. Depression and gener-
alized anxiety disorder: Co-occurrence and longitudinal patterns in elderly
patients. The American Journal of Geriatric Psychiatry. 2005;13(1):31–39.
https://doi.org/10.1097/00019442-200501000-00006.
72. Kurawa SS. The impact of disability on self and society: An agenda for
research on rehabilitation of disabled in Nigeria. Procedia-Social and Behav-
ioral Sciences. 2010;5:1804–1810. https://doi.org/10.1016/j.sbspro.2010.
07.368.
73. Hatzenbuehler ML, Phelan JC, Link BG. Stigma as a fundamental cause
of population health inequalities. American Journal of Public Health.
2013;103(5):813–821. https://doi.org/10.2105/ajph.2012.301069.
74. Kamieniecki GW. Prevalence of psychological distress and psychiatric disor-
ders among homeless youth in Australia: A comparative review. Australian
and New Zealand Journal of Psychiatry. 2001;35(3):352–358.
75. Williams A. Patients with comorbidities: Perceptions of acute care services.
Journal of Advanced Nursing. 2004;46(1):13–22. https://doi.org/10.1111/j.
1365-2648.2003.02961.x.
76. van der Aa MJ, van den Broeke JR, Stronks K, Plochg T. Patients with
multimorbidity and their experiences with the healthcare process: A scoping
review. Journal of Comorbidity. 2017;7(1):11–21.
77. Marais BJ, LönnrothK, Lawn SD, et al. Tuberculosis comorbidity with com-
municable and non-communicable diseases: Integrating health services and
control efforts. The Lancet Infectious Diseases. 2013;13(5):436–448. https://
doi.org/10.1016/s1473-3099(13)70015-x.
78. Boyd CM, Darer J, Boult C, Fried LP, Boult L, Wu AW. Clinical practice
guidelines and quality of care for older patients with multiple comorbid
diseases: Implications for pay for performance. JAMA. 2005;294(6):716–
724. https://doi.org/10.1001/jama.294.6.716.

2
Models of Comorbidity
Rhonda Brown and Einar Thorsteinsson
2.1 Computational and Clinical Models
of Concurrent Symptom Development
Several authors have suggested that unravelling the causes of comorbidity
ranks among the top clinical priorities [1, 2]. However, most existing the-
ories of disease comorbidity provide only a broad overvie w of the manner
in which comorbidity is likely to arise. Logically, there are several broad
hypotheses that can be advanced to explain the existence of comorbidities,
including that: (i) a causal relationship exists between the coexisting dis-
orders; (b) a common factor(s) increases the likelihood that both disorders
will occur; and/or (c) the relationship is spurious [3]. However, the broad
overarching theories have, for the most part, not been tested empirically.
R. Brown (
B
)
Australian National University, Canberra, ACT, Australia
e-mail: rhonda.brown@anu.edu.au
E. Thorsteinsson
University of New England, Armidale, NSW, Australia
e-mail: ethorste@une.edu.au
© The Author(s) 2020
R. Brown and E. Thorsteinsson (eds.), Comorbidity,
https://doi.org/10.1007/978-3-030-32545-9_2
23

24 R. Brown and E. Thorsteinsson
Further, few comorbidity theories are comprehensive yet specific enough
to help guide the exploration of relationships between specific comorbid
disorders and the likely role played by intervening factors. As a result,
we know little about the extent to which comorbidity is relevant to our
understanding of single disorders and conditions; the mechanisms which
likely underpin the development of comorbidities; and the nature of the
interactions between specific risk factors and comorbid disorders.
Nevertheless, in some instances, there is clarity as to the likely tem-
poral evolution of the clinical co-occurrences (e.g. mood disorders and
insomnia) [4]. However, bidirectional relationships are ubiquitous in the
scientific literature, and they have been documented in regards to most of
the disorders and symptoms covered in this book. For example, anxiety
and depression can predict the later onset and/or worsening of impaired
sleep, but, additionally, sleep problems can predict the later onset or wors-
ening of anxiety and depressed mood [4]. Crucially, we do not yet fully
understand the nature of these so-called bidirectional relationships. In
particular, noting the existence of a bidirectional relationship between
anxiety and depression over time tells us nothing about how the disorders
are functionally related to each other, including whether (or not) they are
causally related.One possibility, as discussedin Chapter 6,isthatimpaired
sleep and low mood are causally related to each other; such that sleep dis-
turbance can impair a person’s mood and low mood can worsen sleep, but
it is unclear exactly how this occurs and whether the mechanism/s is the
same (or different) in each case.
In contrast, it might be the case that the relationship is spurious.For
instance, anxietyand depression symptomstend to overlap witheach other
(e.g. impaired sleep is characteristic of both states) [5]; and the Diagnos-
tic and Statistical Manual of Mental Disorders-5 (DSM-5) criteria for
the disorders includes a similar range of symptoms (e.g. impaired sleep,
gut problems) [5]. Further, the scales and clinical interviews that exam-
ine these states tend to ask about a similar range of somatic and affective
symptoms. Thus, the observed relationship between anxiety and depres-
sion may at least in part be a by-product of these overlapping symptoms
and/or the double-counting of the symptoms, although this is unlikely to
fully explain the observed relationships [6, 7]. Finally, it is possible that a
common factor (e.g. stressfullife-events) can explainthe tendency of people

2 Models of Comorbidity 25
to experience comorbid anxiety and depression; for example, stress may
result in rumination at night which interferes with sleep and, in turn, this
may contribute to anxiety and/or depressed mood [8]. However, it is not
exactly clear how anxiety and depression comorbidity develops, despite
the plethora of research on the topic, and partly this is due to the lack of
complex real-world models of anxiety and depression co-causation.
Outside the context of anxiety and depression comorbidity, even less is
known about the roots of comorbidity, even in the case of disorders that
are highly comorbid with each other (e.g. obesity, insomnia). Relatively
few studies in the scientific literature have specifically sought to address
this comorbidity, and few clinical theories have been developed to explain
the phenomenon. Thus, there is a crucial need to develop a theoretical
model/s that can parsimoniously explain the presence and development
of the comorbidities.
Nevertheless, some specific (but limited) theories of comorbidity do
exist which seek to explain the mechanisms by which specific disorders
can co-occur. For example, anxious and/or depressive rumination [9]and
cognitive and somatic arousal (i.e. stress-diathesis model of insomnia)[10]
are posited to interfere with the onset of sleep in some people (e.g. insom-
niacs), and, over time, this may contribute to shorter sleep duration and
cumulative tiredness,if the hyper-arousal orru mination persists over time.
Additionally,late night-eatinghas beenposited to interferewith sleeponset
and shorten sleep duration, and as a result, people with night-eating syn-
drome are likely to develop sleep problems and be overweight/obese, rela-
tive tounaffected individuals [11,12]. However, as discussed in Chapter3,
it is unclear exactly how overweight/obese people will develop comorbid
sleep problems, for example whether the weight or sleep problem develops
first and the exact mechanism/s by which the late night-eating impacts on
sleep and weight.
As detailed in Chapters 3, 4,and7, overweight/obese people are at an
increased risk of developing a range of other comorbid disorders and con-
current symptoms including stress, anxiety, depression, binge-eating dis-
order, diabetes mellitus type-II, and sleep-disordered breathing, relative to
unaffected individuals, which mightalso contributeto morbidityand mor-
tality in affected individuals. Thus, it is apparent that overweight/obesity
is highly comorbid with many different disorders, although we know little

26 R. Brown and E. Thorsteinsson
about the specific mechanisms underpinning some of the comorbidities.
As a result, if an overly specific mechanism (e.g. night-eating syndrome
diagnosis) is examined for its utility in explaining the sleep and weight
problems in overweight/obese individuals, we may learn little about the
extent to which other concurrences (e.g. depression) or related risk factors
(e.g. physical inactivity) will interact together to contribute to the prob-
lems. Clearly, there is a crucial need to employ a more holistic theoretical
approach to the problem of disease comorbidity, which specifies the likely
roles played by multiple different intervening variables.
Currently, there are only two theories that have sought to explain the
presence and development of comorbidity in regards to multiple disorders
and symptoms.The first is a computational model that seeks to explain the
co-occurrence of multiple psychiatric symptoms. Schmittmann and col-
leagues [13] have used a network approach to conceptualise psychological
attributes (e.g. anxiety) as ‘networks of directly related observables’; that
is, a single construct (e.g. anxiety) might be conceptualised as a network of
related variables (e.g. somatic arousal, cognitive arousal, fear cognitions),
which overlaps with other constructs (e.g. somatic arousal, depression).
In another paper, the authors [1] sought to examine the network’s struc-
ture and its dynamics in an effort to replicate the empirical evidence of
psychiatric symptom comorbidity, using simulation methods to evaluate
the plausibility of the network’s properties. This work has resulted in the
network model of psychiatric symptoms that was derived from the analysis
of overlapping symptoms in DSM-4.
In their computational model, individual DSM-listed symptoms were
represented as individual nodes. In the analysis, nearly one-half of the
entire DSM-4 network of psychiatric symptoms (N = 208 symptoms,
across 69 disorders) was shown to be connected in the so-called giant
component. In the computational models, the distances between the
nodes for major depressive episode (MD) and generalised anxiety dis-
order (GAD) were reported to be consistent with the published comor-
bidity rates for the disorders, and model simulations of MD and GAD
reproduced the published population statistics (e.g. prevalence statistics)
for the two disorders [1].
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