First Line Treatment
About OCD
The reader must be aware that the following information about treatment options is intended only as a range of treatment approaches available for people with OCD. The goal is to provide an overall understanding of these therapies sufficient to enable more informed interactions with physicians and therapists. The numerous OCD treatment options currently available, and the variability of specific OCD characteristics, are taken into account by physicians and therapists when making treatment recommendations. Better insights into these factors will, hopefully, allow patients and families to be more active participants in discussions and treatment decision-making with their OCD specialists.
What Is OCD?
OCD is one of the most commonly occurring mental health disorders. It affects about 2% to 3% of people in Western general populations. It is characterised by recurring intrusive thoughts that are very hard to prevent or control (the obsessions).
These lead to irresistible and recurring behaviours (the compulsions or rituals). Compulsions are actions taken to negate or resolve the disruptive, anxiety provoking and disturbing thoughts. A familiar example are those individuals so fearful of “contamination” from everyday activities, such as using a keyboard, touching a doorknob, or handling a notebook, that they feel compelled to scrub their hands with soap and water or a disinfectant many dozens of times a day and despite raw skin from the cleansers.
Other unwanted obsessive thoughts can have more disturbing and aggressive themes. Intrusive thoughts/obsessions/compulsions may occur so frequently that they disrupt personal relationships, work, sleep and almost all other aspects of daily life.
Many people experience troubling, unwanted thoughts occasionally. However, in those without OCD, these thoughts are given little importance, do not necessarily compel any actions, and easily disappear. By comparison, in those with OCD, the thoughts or impulses are intense, relentless and can cause tremendous anxiety, guilt, and disgust.
The themes of the intrusive thoughts in people without OCD may be quite similar to those occurring in OCD. It is not necessarily the nature of the obsessive thought that defines OCD, but rather how that thought is interpreted and acted upon by the patient.
Regrettably, OCD is usually a lifelong condition that waxes and wanes in intensity and frequency. Treatment can help manage the obsessions and compulsions, so that they are less disruptive. However, existing treatments for OCD are often ineffective, which is why we are pushing for the development of new and better treatments for this devastating condition.
FIRST LINE TREATMENT WITH COGNITIVE BEHAVIOURAL THERAPY
The two principal types of OCD treatment are cognitive behavioural therapy (CBT) and medication. Evidence of clinical effectiveness has been amply demonstrated for both and each has a role in OCD symptom control. Whether to begin treatment with CBT, medication, or both, depends on the assessment of the type and severity of the OCD, practitioner experience and preference, and patient health and coexisting medical problems. The latter must be considered carefully in order to minimise the risk of treatment noncompliance.
Cognitive therapy and behavioural therapy are separate but complementary treatment methods.
Cognitive therapies help patients to understand their dysfunctional thoughts or beliefs. These insights help to develop greater familiarity and objectivity about the nature of their obsessions.
The behavioural therapy part of CBT most often used for those with OCD is referred to as Exposure and Response Prevention (ERP). ERP is based on the observation that when patients can resist or delay a particular compulsion, even for a short time, the magnitude of their obsessive thoughts may decrease or disappear (habituation). The typical ERP procedure involves deliberate and incremental exposure to those situations or thoughts that are fearful and cause anxiety and requires patients to resist performing any compulsive actions. Conducting ERP therapy can be an extremely stressful exercise, and some whose obsessions are embarrassing and humiliating are unwilling to undergo treatment. When patients complete their ERP treatment course, it has been unequivocally proven to be an effective and often sustainable first line therapy, with as many as 50% to 60% having an initial response.
It is not yet completely clear whether CBT or medication (usually SSRIs – see below) is the first line treatment of choice. In general, although both CBT/ERP treatment and first line drug therapy have been effective in OCD, it appears that the reported levels of improvement from ERP are more consistent than drug treatment. For patients eligible for either approach, ERP may be more attractive, and will avoid undesirable drug side effects.
NEUROTRANSMITTERS AS TARGETS FOR DRUG THERAPY
Imbalances of certain neurotransmitters are thought to play important roles in OCD. Most current and emerging drug treatments for OCD, in different ways, are intended to mitigate the abnormal balance.
Numerous types of neurotransmitters have functional roles in the brain that are critically essential to all aspects of brain function. Neurotransmitters function by facilitating, inhibiting, or otherwise altering the nerve-signalling pathways for any or all brain functions.
Abnormalities of neurotransmitter function appear to have central roles in OCD.
Genetic, functional brain imaging, and clinical analyses of OCD patients point to several neurotransmitters as likely contributors to the development of the disorder. These are glutamate, gamma-aminobutyric acid (GABA), serotonin (5-HT), and dopamine.
Glutamate, the most abundant neurotransmitter, acts to increase the excitability of nerves. Excessive brain nerve excitability from elevated levels of glutamate and dopamine is thought to be central to OCD behaviours. In fact, when otherwise normal laboratory animals have glutamate levels artificially increased, they exhibit OCD-like behaviour.
There also are findings to support an important role for dopamine in OCD. Among its neurotransmitter functions, dopamine mediates compulsions, and the sense of satisfaction and pleasure from a particular experience. In a sense, compulsions can be thought of as attempts to relieve the extreme anxiety that results from obsessive thoughts. One hypothesis is that excess dopamine reinforces the sense of relief (the “pleasurable” experience) when a compulsion offsets the distress of a particular obsession.
Gamma-aminobutyric acid (GABA) is the second most abundant neurotransmitter, and has a role opposite to glutamate, acting to reduce nerve excitability throughout the nervous system including the brain. The levels of GABA in OCD patients tend to be low and insufficient to offset neurostimulation. In addition, low brain serotonin levels are regularly seen. Serotonin and several other neurotransmitters play important roles in response inhibition which is particularly poor in OCD. When serotonin availability is increased with drug therapy, glutamate levels decrease and GABA levels rise, with a net effect of diminished neurostimulation. Serotonin appears to be a modulator of excitatory nerve transmission – acting as one investigator describes, as a nerve transmission “brake”.
Current gene research has identified several abnormalities that may result in abnormal neurotransmitter structure or function. An understanding of the different forms of neurotransmitter dysfunction that likely play roles in OCD enables a more focused approach to developing new drugs and therapies to prevent those specific neurotransmitter disturbances responsible for OCD symptoms.
Considering OCD as a group of similar disorders with somewhat different manifestations also may explain why there is so much variability of drug treatment effectiveness, and why trial and error and combination therapy are often needed.
FIRST LINE DRUG TREATMENT OF OCD
Selected drugs that are commonly used, or show promise, in OCD management are included in this section, and the information will be updated as progress demands. Most people with OCD are initially managed as outpatients, although hospitalisation may become necessary if a patient becomes dysfunctional with a severe relapse, is causing significant disruption at home or at work, and certainly if there appears to be a risk of suicide. Despite a great deal of research, the results of a great many studies show mixed or even conflicting results for the drugs used in OCD. While this can cause great frustration for patients and their health professionals, an effective treatment strategy is eventually found for most.
The reader must be aware that the information that follows for all types of treatments is intended to provide an overall understanding of potentially useful treatment approaches for people with OCD. Beyond this, there are numerous other aspects of every patient’s case that will be considered by your OCD specialist in order to make tailored treatment recommendations.
The majority of published guidelines for treatment of OCD recommend using a selective serotonin reuptake inhibitor (SSRI), cognitive behavioural therapy (CBT), or a combination of the two, as initial treatment. SSRIs are best known for the treatment of depression and there are a number of SSRIs currently available. In general, the actions of these drugs result in increased availability of serotonin. As already stated, increased serotonin levels lead to reduced glutamate and increased GABA in many parts of the brain. This is thought to be the action responsible for its effectiveness in OCD.
The results of treatment with different SSRIs are essentially comparable and there is no current consensus about which SSRI is most effective for OCD treatment. There are, however, differences in their side effect profiles that may be of some importance in individual patients. Although clomipramine (a tricyclic antidepressant) has usually shown equivalent to somewhat better treatment results compared to SSRIs, its side effect profile makes it a generally less preferred choice as first line therapy. Overall, about 40% to 60% of patients treated with SSRIs have satisfactory improvement of their symptoms. Investigations of effectiveness using SSRI and CBT combination therapy have also shown greater benefit compared to SSRI alone.
There is existing evidence that those who are unresponsive to a particular SSRI may benefit from substituting a different one. There also is a solid consensus that for greatest effect, patients with OCD generally require SSRI doses in the upper to near maximal range, if tolerated. This observation is not restricted to any one SSRI drug and, unfortunately, many OCD patients receiving SSRI turn out to be undertreated. A treatment period of at least 8 to 12 weeks is recommended before concluding that there is lack of efficacy. Numerous patients will prematurely consider their SSRI treatment ineffective and discontinue treatment too soon.
| Serotonin reuptake inhibitor | Starting dose (mg / day)a | Usual target | Usual maximum |
|---|---|---|---|
| Clomipramine | 25 | 100-250 | 250 |
| Escitalopram | 10 | 20 | 40 |
| Fluoxetine | 20 | 40-60 | 80 |
| Fluvoxamine | 50 | 200 | 300 |
| Paroxetine | 20 | 40-60 | 60 |
| Sertralined | 50 | 200 | 200 |
*From Seibel P & Hollander E (2014). F1000 Prime Rep, 6, 68. (41)
As already stated, clomipramine has demonstrated effectiveness as first line therapy for OCD. This medication is in a different drug class (tricyclic antidepressant) but also causes serotonin levels to increase. It has been tested head-to-head with different SSRIs with little to no consistent differences in results. Many of clomipramine’s side effects are similar to those of the SSRIs. However, they tend to be more severe and cause more treatment dropouts than the SSRIs. The most frequent side effects rated by patients as obstacles to treatment were sexual dysfunction (males more than females), weight gain, and sleep disturbances. Serious heart rhythm disturbances and seizures, while uncommon with clomipramine, are much less likely with SSRIs. Given the frequency and degrees of side effects with clomipramine, an SSRI is usually preferred for the initial medication trial, particularly if long-term therapy is anticipated.
*The Y-BOCS is a scale that rates severity of OCD and is the most widely used assessment tool for OCD. It can be used to measure change of OCD severity such as before and after a treatment, and also to compare treatments. Its OCD scores are: 0-7 subclinical; 8-15 mild; 16-23 moderate; 24-31 severe, and 32-40 extreme.