Comorbidity of mental disorders and substance use: a brief guide for the primary care clinician
6.1 Anxiety
In contrast to fear, which is a response to a realistic immediate danger, anxiety is a fearful response occurring in the absence of a specific danger or real threat. According to the National Survey of Mental Health and Wellbeing, anxiety disorders are the most common form of mental disorder in the population with a one-year prevalence of 9.7% in Australian adults(68).
The fear and worry associated with anxiety arises in response to a variety of specific triggers (fear of heights) more general triggers (e.g. crowds, shopping centres, being in trains or buses, meeting new people, or having to speak in public) or sometimes in response to general issues including finances, health or relationships and personal safety. In some cases, anxiety can arise suddenly and spontaneously without a discernable trigger, as is the case with panic disorder.
People with anxiety may find it hard to relax, concentrate and sleep, and may suffer physical symptoms such as heart palpitations, tension and muscle pain, sweating, hyperventilation, dizziness, faintness, headaches, nausea, indigestion, bowel disturbance and loss of sexual pleasure. These symptoms are accompanied by changes in thoughts, emotions and behaviour that substantially interfere with the person's ability to live and work.
More women than men experience anxiety disorders(68, 119, 121, 201). Anxiety usually begins in early adulthood and is often, but not always, triggered by a series of significant life events.
6.1.1 Anxiety disorder subtypes
Panic disorder
This is characterised by recurrent panic attacks, which occur unexpectedly over at least a month. Panic attacks are diagnosed if there is a period in which there is a sudden onset of intense apprehension, fearfulness or terror commonly associated with feelings of impending doom. Symptoms such as shortness of breath, palpitations, chest pain or discomfort, smothering or choking sensations along with fear of losing control are experienced during these attacks.Agoraphobia
This is characterised by anxiety about, or avoidance of, places and situations from which escape may be difficult (e.g. elevators, buses, trains or trams or shopping centres), or in which help may not be available in the instance of experiencing a panic attack or panic like symptoms.Social phobia
This is characterised by clinically significant anxiety provoked by being exposed to certain types of social situations, commonly leading to avoidance of situations requiring socialising.Obsessive compulsive disorder (OCD)
This is characterised by obsessions that cause significant anxiety or distress and compulsions which serve to neutralise the associated anxiety or distress.Post traumatic stress disorder (PTSD)
This is characterised by re-experiencing of an extremely traumatic event accompanied by symptoms of increased arousal and avoidance of stimuli associated with the trauma.Generalised anxiety disorder (GAD)
This is characterised by at least six months of persistent and excessive anxiety or worry.Top of page
6.1.2 Management approaches to anxiety disorders
- Anxiety disorders are treatable conditions, although as with all medical disorders, there is a spectrum of severity. Some are chronic. Anxiety disorders have a generally unappreciated high rate of morbidity and mortality(196).
- Discussions with the patient regarding treatment should involve both short- and long-term outcome goals(196).
- Treatment of the anxiety disorders vary depending on the nature of the condition and the circumstances of the individual. In most cases, CBT is first-line treatment****(202) and is cheaper and more effective than medication, especially in those individuals who have had little or no previous exposure to benzodiazepines.
- In the majority of situations, however, by the time people seek advice from a clinician they are not generally benzodiazepine naïve and the issue expands to management of anxiety as well as controlling benzodiazepine use.
- Patients taking benzodiazepines do not develop tolerance to their anxiolytic effects(196) which significantly contributes to the desire to continue with their use. Benzodiazepines are particularly best avoided as a long-term medication treatment in the elderly because of the risk of adverse effects.
- CBT is effective in reducing symptoms of anxiety****(202) and will be more effective if there is minimal sedation and anxiolysis due to benzodiazepine use(196).
- However, CBT can be and is effective when administered concurrently with benzodiazepine dose reductions****(202-204). CBT has been shown to improve the likelihood of patients successfully tapering and ceasing benzodiazepine use when they also have an anxiety disorder***(204).
- Tricyclic antidepressants and SSRIs are equally effective and preferable to benzodiazepines because of problems with sedation and associated dependence and withdrawal.
- People with social phobias may show some treatment response with antidepressants, in particular SSRIs****(205-213). People with OCD also respond well but require higher than normal doses(214-218).
- Benzodiazepines may be more useful than antidepressants for GAD, panic disorder and agorophobia*(196). However, both anti-depressants and/or benzodiazpeines should only be used after other treatment approaches have been unsuccessful. That is, they should only be used as a third or fourth line of treatment when patient responses to other forms of management have been unsuccessful.


