Comorbidity of mental disorders and substance use: a brief guide for the primary care clinician
10.2 Comorbidity with somatoform disorders
- Somatic presentations of underlying mental disorder or distress are extremely common in general practice with somatisation frequently being a way of presenting anxiety and depression(388). Many of these presentations are easy to sort out for the clinician, with the underlying stressor or disorder quickly coming to the fore and the patient willing to attribute the physical symptoms to the underlying problem.
- There is a linear relationship between the severity of anxiety and depression and frequency and severity of somatic symptoms(389-392).
- There is a high degree of comorbidity with depression and anxiety amongst people with somatoform disorders(389, 392-398). A combination of anxiety and depression and a somatoform disorder results in more somatic symptoms than if anxiety or depression alone occurs with the somatoform disorder(392, 396, 398). Individuals with somatoform disorders and comorbid depression may use both organic and psychological explanations for their symptoms(399).
- Overlap of symptoms of diagnostic criteria for somatoform disorders and anxiety and depression may explain the high prevalence of somatic symptoms in those with anxiety and depression(392, 400).
- Anxiety and depression are more likely than somatoform disorders to be the source of medically unexplained symptoms(401). Regardless, depression and anxiety make pain feel worse and individuals present with a higher level of functional somatic symptoms(392, 402).
- There is obvious scope for inappropriate substance use in these individuals as the medical practitioner attempts to deal with some of the symptomatology before the correct diagnosis is recognised(377, 403).
- There are strong correlations between pain disorders and opioid dependence and misuse. However, this does not suggest that all people with pain and opioid dependence have a somatoform disorder.
- Somatoform disorders also correlate with alcohol and benzodiazepine dependence and misuse(379, 404).
- Delay in diagnosing these disorders may result in the individuals being prescribed opioids or benzodiazepines with subsequent increased risk of dependence(404).
10.2.1 General management approaches to comorbidity
- The challenge is to recognise the diagnosis of somatoform disorder early.
- Psychosocial assessment should be performed prior to treatment with any form of pharmacological treatment(405).
- Clinicians need to be aware of comorbid anxiety and depression in those with somatoform disorders and manage them accordingly(392, 398).
- In determining whether the depression is a cause or an effect of chronic pain or somatoform disorders, it should be considered at least a comorbid condition that requires concurrent treatment(402). Use of antidepressants has been shown to be effective in reducing somatic symptoms in those with depression and anxiety(406, 407).
- Use of antidepressants may be required for comorbid depression and anxiety***(406, 407), with tricyclics being useful(377) in aiding chronic tension headaches and fibromyalgia.
- Understanding the impact of fear, expectations and attention can help physicians deal more effectively with acute pain(402).
- There is evidence that pain perception seems to be responsive to changes in patient mood, even in people with concomitant substance use**(408). This supports cognitive approaches to pain management even in substance dependent individuals.
- Cognitive approaches may result in improved quality of life in patients with long-term somatoform disorders(398).