Having surveyed more than 20,000 patients ...

Surveyed more than 20,000 patients in Germany with the use of strict diagnostic criteria, Wittchen et al. [87] showed that the current prevalence of GAD among patients followed for 558 general practitioners, is 5,3%, of which only less than a third have both depression. Thus, the comorbidity of depression and GAD in general practice is lower than in studies conducted on patients in psychiatric institutions, where it reaches 60-80% [12]. Prospective epidemiological studies have shown that GAD - no prodromal stage of other anxiety and depressive disorders, as an independent disease [53]. The presence of primary GAD increases the risk of first depressive episode in 4,5-9 times [13.78], almost a factor of 2 increases the duration of depression [47], reduces the likelihood of remission, and increases the risk of suicide attempts [12.25]. These and many other data suggest that in most cases, a combination of GAD with depressive states initially arises precisely GAD [28.87]. This is also indirectly indicated by the first publication that the drug therapy of GAD reduces the risk of depression [30]. In practice, should, if possible, to differentiate GAD and depression. Despite the similarity of most of their somatic symptoms for depression are more characteristic of a decrease or increase in appetite and weight and persistent pain without apparent cause somatic [54]. However, major differences are revealed in the psychological symptomatology. When depression is dominated by depressed mood, more often there are thoughts of death and suicidal tendencies. In addition, the symptoms are detected, virtually absent in GAD: loss of desire, pleasure and interest in those activities that were usually pleasant, apathy, loss of self-confidence, lower self-esteem, feelings of hopelessness, pessimism, guilt. Several simplifying, these differences can be described as follows: for depression in a patient as it has no future with anxiety - it is scary and its uncertainty. Many neurobiological parameters (regionarny cerebral blood flow, metabolic activity) with GAD have normal basal levels - in contrast to the depression in which the same indicators are lowered or raised. Identified neurochemical changes in the GABA and benzodiazepine receptors, as well as noradrenergic and serotonergic systems of the CNS differ significantly from the anomalies detected in depression. Another evidence of qualitative differences between GAD and depression are some of the neurophysiological features of sleep structure [66]. In general practice the doctor must not only carry out a differential diagnosis of GAD and systemic diseases, but to deal with their combination. Having surveyed more than 2,500 somatic patients, Wells et al. [86] concluded that the only mental health problems, clearly and independently associated with chronic somatic diseases, were alarming.