[Anxiety and depression in chronic back pain patients: effects on beliefs of control and muscular capacity].

Chronic back pain patients often show a fear- and depression-related behavior with social retreat and less physical activity. Increasing pain is associated by decreasing muscular capacity of the spine stabilizing muscular system. The aim of the present study was to analyse the level of anxiety and depression (HADS-D) among chronic low back pain patients (n = 685) in ambulatory treatment in comparison with standardised values of a representative German adult population sample (n = 1943). Furthermore, the association between conspicuous values of anxiety or depression and beliefs of control (KU-WS) and muscular capacity (isometric power of lumbal extensor and flexor) were analysed. Back pain patients showed significantly higher mean scores in anxiety and depression without a significantly correlation to the age. Female subjects were more anxious than males. 14.9 % showed conspicuous values of anxiety, 16.1 % of depression. Patients with conspicuous values of anxiety and depression respectively showed lower levels of internal beliefs of control and muscular capacity. The present study confirms the importance of early anxiety and depression screening in patients with low back pain in ambulatory treatment to figure out risks of chronicity and to derive optimal treatment.