7.3. Clinical implications

Both atopic disorders and depression are illnesses of major public health concerns and are therefore of considerable importance in most Western countries. Since about one million Finnish people (20% of all Finns) are suffering from atopic disorders, and because they are shown to have an increased likelihood of suffering from depression, also the co-morbidity between these two disorders is worth being taken note of from the viewpoint of public health. Co-morbidity, thus, should be taken seriously and monitored in clinical practice.

Based on the findings of this thesis and earlier studies, there seems to be at least a subset of patients for which the interrelationship between atopic allergies and depressive symptoms may be very salient (Wamboldt et al. 2000). This is noteworthy at clinical work while treating atopic and/or depressive patients. Due to psycho-neuroimmunological interactions, it could be hypothesized that the adequate treatment of co-morbid depression in atopic patients would be beneficial for the successful management of atopic symptoms, and vice versa. Untreated atopy should also be kept in mind as one possible etiological factor behind the treatment-resistant depression. On the other hand, the possibility of an underlining depression has to be remembered when treating persistent atopic symptoms, and as a potential cause for the exacerbation of an atopic condition. When conducting randomized follow-up studies in atopic patients, the procedure should also include repeated screenings with regard to depressive symptoms. This would help to establish, whether a medication for atopy is successful in the treatment of depression as well, or may even prevent the development of depressive disorders.

Given that there exists an inflammatory stage in the human body during allergic reactions, an untreated atopy most probably exposes at least some persons to depression. Thus, early detection and treatment of atopic disorders might promote mental health by preventing the development of depressive disorders. On the other hand, since many other physical disorders have been shown to be associated with depression, diverse approaches involving basic, clinical, epidemiologic, and services-related research efforts are being called for to understand how depression eventually arises and can best be prevented and treated in the context of physical disorders (Stover et al. 2003).

Once a deeper understanding about the pathophysiology behind the body-mind interactions has been obtained, new treatment strategies for both disorders can apparently evolve. In the case of co-morbid atopy and depression, the drug of choice would be a preparation, which has been developed to have an effect on the pathophysiology, which is common for both disorders. For example, if the HPA axis activation turned out to be causally linked with co-morbid atopy and depression, the therapy should then be focused on the corresponding or accompanying neurobiological abnormalities (Holsboer 2001).