ARTICLE IN PRESS
Hypothesis: The Chaos and Complexity Theory May Help
our Understanding of Fibromyalgia and Similar Maladies
Manuel Martinez-Lavin, MD, Oscar Infante, DVM,
and Claudia Lerma, PhD
Background: Modern clinicians are often frustrated by their inability to understand fibromyalgia
and similar maladies since these illnesses cannot be explained by the prevailing linear-reductionist
medical paradigm.
Objective: This article proposes that new concepts derived from the Complexity Theory may help
understand the pathogenesis of fibromyalgia, chronic fatigue syndrome, and Gulf War syndrome.
Methods: This hypothesis is based on the recent recognition of chaos fractals and complex systems
in human physiology.
Results: These nonlinear dynamics concepts offer a different perspective to the notion of homeostasis and disease. They propose that the essence of disease is dysfunction and not structural
damage. Studies using novel nonlinear instruments have shown that fibromyalgia and similar
maladies may be caused by the degraded performance of our main complex adaptive system. This
dysfunction explains the multifaceted manifestations of these entities.
Conclusions: To understand and alleviate the suffering associated with these complex illnesses, a
paradigm shift from reductionism to holism based on the Complexity Theory is suggested. This
shift perceives health as resilient adaptation and some chronic illnesses as rigid dysfunction.
© 2007 Elsevier Inc. All rights reserved. Semin Arthritis Rheum xx:xxx
Keywords: fibromyalgia, chronic fatigue syndrome, chaos, Complexity Theory, irritable bowel, Gulf
War syndrome, neuropathic pain, complex adaptive systems, autonomic nervous system
The whole is more than the sum of its
parts—Aristotle
M
odern clinicians are often frustrated by their
inability to understand common complex syndromes such as fibromyalgia (FM) and similar
maladies because such illnesses cannot be properly explained through the prevailing linear-reductionist medical paradigm. This poor understanding often severs the
patient–physician relationship and consequently results
in persistent patient suffering and dissatisfaction.
This article proposes that new paradigms derived from
the Complexity Theory may help us better understand
these multifaceted syndromes. The focus of the proposal
is on FM, but the hypothesis may be also relevant to
related overlapping conditions such as the chronic fatigue, Gulf War, and irritable bowel syndromes. The hypothesis is based on the recent recognition of chaos frac-
National Institute of Cardiology, Mexico City, Mexico.
Address reprint requests to Manuel Martinez-Lavin, MD, National Institute of
Cardiology, Juan Badiano 1, 14080 Mexico City, Mexico. E-mail: mmlavin@
infosel.net.mx.
0049-0172/07/$-see front matter © 2007 Elsevier Inc. All rights reserved.
doi:10.1016/j.semarthrit.2007.04.003
tals and complex systems in human physiology (1,2).
These nonlinear dynamics concepts offer a different perspective to the notion of health and disease. Studies using
nonlinear methods have suggested that FM and similar
maladies may be caused by the degraded performance of
our complex adaptive systems (3).
METHODS
New concepts derived from the Complexity Theory are
reviewed. Based on this theory, a new perspective on FM
is offered.
RESULTS
The Complexity Theory
Scientists frequently view the universe as a linear place,
one where the simple rules of cause and effect apply,
and where the strength of the response is proportionate
to the magnitude of the stimuli. This is analogous to
the way one studies a big machine and takes it apart to
understand its components, and in that manner, understands the whole. However, after the introduction
1
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ARTICLE IN PRESS
of computer modeling and simulation, it became clear
that the universe is full of systems that do not follow
this linear behavior. In such networks, proportionality
does not hold, and small changes can have striking and
unanticipated “chaotic” effects. These systems cannot
be understood by analyzing their individual components (1,2). As scientists of all disciplines explored
these phenomena, a new field of study emerged, The
Complexity Theory, which is based on relationships,
emergence, patterns, and iterations. The roots of this
theory are found in Poincaré’s “restricted 3-body problem” in the early twentieth century (4) and on the
cybernetic model developed by Wiener and Rosenblueth (5).
As a consequence of this emerging knowledge, novel
concepts appeared. Some of them are essential to comprehend this hypothesis (1,2).
Complex systems are macroscopic collections of simple
(and often nonlinearly) interacting units that are endowed with the ability to evolve and adapt to a changing
environment. The control of a complex system tends to be
highly dispersed and decentralized with negative (damping) and positive (amplifying) feedback loops. These
features provide resilience in the face of environmental
perturbation, thus the term complex adaptive systems.
Examples of complex systems are democratic societies,
stock markets, ant colonies, the immune system, and the
autonomic nervous system (ANS).
Emergence is the process of complex pattern formation
from more basic constituent parts or behaviors. An example is the interactions between a great number of neurons
producing a human brain capable of thought. The constituent neurons are not individually capable of thought.
Emergent structures are more than the sum of their parts
because the emergent order will not arise if the various
parts are simply coexisting; the interaction of these parts is
central.
Chaos refers to apparently random unpredictable variability that can arise from the operation of complex systems. The unpredictability comes from a property known
as “sensitivity to initial conditions,” which means that
small changes or perturbations can produce large transformations in the behavior of the system in the long term
(“the butterfly effect”). Chaotic systems can also have bifurcations (sudden changes in behavior in response to
small change in 1 parameter or property of the system).
Chaotic behavior can be seen in different networks of the
human body such the nervous or immune systems.
Fractal is a geometric concept related to chaos. A fractal
is an object composed of subunits that resemble the larger
scale structure, a property known as “self-similarity.”
Most important human structures have fractal anatomies.
Perhaps the best example is the pulmonary circulation.
The pulmonary artery branches thousands of times before
reaching the capillary bed. The microscopic pulmonary
subunits and its larger counterparts are shaped identically.
Fractal structures are extremely efficient for transporta-
The Chaos and Complexity Theory and fibromyalgia
tion, distribution, and exchange. Fractal also has a time
domain concept that is applied to complex processes lacking a single time scale (1,2).
DISCUSSION
The Concept of Disease: Time to Amend
the Paradigm
The prevailing paradigm considers medicine to be a linear
scientific discipline. It views the human body as a big
machine that can be understood by carefully examining
its parts. This reductionist approach has been useful in
understanding many “linear” diseases. The cause– effect
of an infection or a tumor causing organ damage led to the
very useful clinical–pathologic correlation. Such educational exercises are still the main event in many medical
centers and medical journals. Therefore, current scientific
thinking demands that a “true” disease must have structural (or at least serological) alteration. According to this
view, if a clinical syndrome (the effect) does not have an
underlying anatomic alteration (the cause), then either
the syndrome is nonexistent or the illness belongs to the
realm of psychiatry. This sophism derives in part from
Rene Descartes’ philosophy that distinguished between
res cogitans and res extensa. The former referred to the soul
or mind and was said to be essentially “a thing which
thinks.” The latter was the material stuff of the body. Its
primary characteristic was extension: it occupied space
and was therefore amenable to measurement (6).
An alternative view envisioned by Claude Bernard in
the nineteenth century, and supported by the Complexity
Theory, is to define disease as dysfunction. Structural
damage without dysfunction is not disease. Dysfunction
with or without structural damage is disease. Thus disease
can be broadly defined as a bio-psycho-social alteration
that generates suffering (7) and/or decreases longevity.
Disorder Is Healthy, Uniformity Leads
to Disease
Conventional medical wisdom contends that diseases
arise from deviances of the orderly machine-like systems
of the body. The Complexity Theory challenges this view,
suggesting instead that the opposite is true (2). A system
in idle equilibrium does not have the internal dynamics
enabling it to respond to its environment and will ultimately die. A system in deterministic chaos may have
resilience in the face of external stressors. A good example
of healthy chaotic behavior is the constant variation of the
heart beat (8).
In normal circumstances, the heart rate is not fixed,
rather it varies constantly in a seemingly random way,
particularly during resting conditions. Irregularity of the
heart beats follows a circadian rhythm with increased beat
dispersion during sleep (9).
Analyses of the variability of heart rate, looking at trajectories in the space, and self-similarity properties have
revealed chaotic behavior (9,10).
ARTICLE IN PRESS
M. Martinez-Lavin, O. Infante, and C. Lerma
Healthy individuals have widely varying heart beats. In
the presence of disease or aging, the system loses complexity and this variability decreases (9). In elderly persons,
altered fractal scaling properties of heart rate are a predictor of sudden death (11).
The Autonomic Nervous System, a Prototype
of a Complex Adaptive System
The ANS is an intricate network in vertebrate animals
that serves to regulate the most important body functions,
including the vital signs. The term “autonomic” reflects
the fact that the system is not governed. Blood pressure
and heart rate (among many other variables) are finely
tuned by harmonious sympathetic–parasympathetic interactions that take place through internal feedback paths.
These 2 branches act as amplifying or damping feedback
loops constantly adapting the body to environmental
changes.
The ANS is the interface between mind and body.
Autonomic activation transforms emotions like fear or
anger into biological functions like paleness, pupil dilation, and tachycardia, among many other reactions.
Therefore this network constitutes the main element of
the stress response system (12). The ANS has all the features of a complex adaptive system.
The performance of this complex adaptive system is
very difficult to assess. Static blood or urine measurements
of autonomic neurotransmitters do not reflect the dynamic nature of the ANS. The introduction of a nonlinear
instrument (heart rate variability analysis) made it possible to follow and estimate the chaotic behavior of this
network (9,10).
Heart rate variability is under the control of the ANS.
Variations in heart period are largely dependent on vagal
modulation. Spectral methodology applied to this variability is capable of defining and quantifying sympathetic
and parasympathetic influences on the sinus node (13).
The Fibromyalgia Problem
FM is a chronic syndrome characterized by widespread
pain and widespread allodynia. Other distinctive features
are paresthesias, sleep disturbances, chronic fatigue, anxiety, and irritable bowel (14). The syndrome affects between 2 and 3% of the general population, the overwhelming majority (⬇90%) being women. FM severely
diminishes the quality of life of the afflicted persons (15)
and imposes a high economic burden on the society (16).
Therefore the condition represents a major health problem for contemporary women.
FM strongly overlaps with other prevalent (and controversial) clinical conditions such as the chronic fatigue and
Gulf War syndromes. Common to these illnesses is the
presence of chronic nonnociceptive pain, unexplainable
fatigue, sleep disorders, cognitive impairment, anxiety,
and depression (17,18). Irritable bowel and temporoman-
3
dibular joint syndrome are, in many instances, localized
expressions of the above-mentioned maladies.
There are no consistent anatomical or serological abnormalities in FM and similar syndromes. This lack of
structural damage led some clinicians to argue that the
illnesses were nonexistent. Nevertheless, it is an undisputed fact that physicians are often consulted by persons
complaining of vexing pain and fatigue that cannot be
explained by any other diagnosis.
Autonomic “Decomplexification” in
Fibromyalgia and Related Illnesses
Different groups of investigators have reported decreased
heart rate variability in patients with FM, as well as a
monotonous circadian rhythm pattern (2,19-25). These
findings are the most consistent alterations so far described in FM. These anomalies can be interpreted as a
“decomplexification” of the ANS, with persistent inflexible circadian sympathetic predominance. Similar heart
rate abnormalities have been reported in conditions that
overlap with FM such as irritable bowel (26,27), chronic
fatigue (28), and Gulf War syndrome (22,29).
It has been suggested that such autonomic dysfunction
explains the multifaceted alterations in FM (30) and that
the main complaint of the syndrome (chronic pain) is
sympathetically maintained. Emerging evidence suggests
that the unbending sympathetic hyperactivity could lead
to neuroplasticity, establishing abnormal connections between the sensory neurons and the sympathetic nervous
system. This type of neuroplasticity is a well-established
phenomenon in the animal model (31). The hormonalinfluenced difference in the behavior of the ANS in
women versus men (32) could theoretically explain the
marked gender difference in the prevalence of FM.
New genomic data reinforce the proposal of FM as
sympathetically maintained pain. Catecholamines are the
sympathetic neurotransmitters. Healthy women with
particular gene polymorphism associated with defective
catecholamine clearing enzymes have increased susceptibility to pain (33).
The mechanisms whereby a breakdown of the ANS
may produce other distinctive FM manifestations have
been discussed previously (30).
This new information suggests that in FM and related
conditions there is degraded performance of the body’s
main complex adaptive system, the ANS. The reason for
this decomposition remains to be established. It is possibly a combination of environmental and genetic factors.
Modern societies have become more stressed (12); they
confront a more hostile environment. An example of the
new challenges are alterations in circadian rhythmicity.
For thousands of years, day and night cycles were harmonious with external cues. Light, noise, and activity during
the day; darkness, rest, and quiet at night. Industrialization has clearly disturbed this harmony. Nowadays there
is light, activity, and noise at night. Another example of
4
ARTICLE IN PRESS
modern stressful situations can be seen in monotonous
working conditions. It has been shown that disability in
FM is associated with repetitive manual tasks, low income, or inability of affected persons to influence their
working environment (34). These and many other stressors of modern societies are likely to have a negative impact on human health. Individuals that are more susceptible to environmental changes (arguably women with
defective catecholamine-clearing enzymes) would,
thereby, be more prone to become ill.
Failed Reductionist Therapies for
Fibromyalgia
Therapy for FM and related illnesses has followed a linearreductionist paradigm. Conventional physician–patient
interaction usually results in tests seeking to probe each of
the patient’s symptoms. The information derived from
these series of tests is typically nonrevealing. Nevertheless,
physicians will write a prescription for several drugs intended to improve each one of the patient’s symptoms.
The results are often frustrating. Symptoms may not improve and patients will often end up polymedicated with
additional suffering caused by the untoward effects of the
drugs.
Interventions that have proven to be partly effective in
these complex syndromes are those multidisciplinary programs that consider a person as a whole, specifically, education, cognitive behavioral therapy, and several types of
exercise programs (35,36). These interventions improve
the resting autonomic tone (37).
It is clear that current therapies for FM and related
illnesses are far from adequate. There is much to be
learned about the pathogenesis of these syndromes to offer more coherent therapy. Meanwhile it seems reasonable
to use a scientifically holistic approach including education, mind– body interventions, and the judicious use of
medications. These interventions can be better delivered
in clinics specifically designed for this purpose (36).
In conclusion, FM and similar maladies are clinical
realities. Attitudes such as denial, scorn, or rejection are
unacceptable in a scientific– humanistic medical environment. Reductionist approaches have failed to comprehend these illnesses. These chronic syndromes could be
better understood on a bio-psycho-social context rather
than attempting to explain such diverse symptoms by the
presence of discrete anatomical or serological alterations.
The use of nonlinear instruments based on the Complexity Theory has revealed degraded complex adaptive systems in FM and related syndromes. Faulty performance
of the ANS provides a coherent explanation for the multifaceted manifestations of these maladies.
Understanding these syndromes calls for a shift in paradigms, from reductionism to holism based on the Complexity Theory. This shift would recognize chaos, fractals,
and complex systems as essential elements in human physiology and would offer a different perspective in which
The Chaos and Complexity Theory and fibromyalgia
health is perceived as resilient adaptation, and some
chronic illnesses are perceived as rigid dysfunction.
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