Although there is no direct causal relationship between age and depression (a higher age may be associated with more illness, and physical illness may be associated with depression [ 16]), depressive symptoms are often observed in elderly populations [ 17].
Furthermore, we examined whether sensory properties of depressive thoughts would be associated with depression severity, suicidality, decreased illness insight and lower quality of life.
We adjusted first for variables known to be associated with depression that might confound any association, for example sociodemographic characteristics, physical and cognitive impairment and severe life events.
Abnormal regulation that produces a deficiency of the amines appears to be associated with depression, and an excess of amines is associated with mania.
Behavioural inhibition and more specifically harm avoidance temperament dimension (HA) has been found to be associated with depression.
Past-year migraine was found to be associated with depression, dysthymia, bipolar disorder, panic attacks, panic disorder, agoraphobia and simple phobia.
The level of serum lipids has been reported to be associated with depression and suicidality, but the exact relationship between these factors remains controversial.
This discrepancy may have been due to the strict selection of episodic migraine in this study with exclusion of tension type headache comorbidity, chronic headache and medication overuse headache, which are well known to be associated with depression [55].
In four longitudinal studies, high levels of CRP were found to be associated with depression even after adjustment for BMI and weight loss, further corroborating the idea that other sources of peripheral inflammation might contribute to depressive symptoms.
Secretive eating, characterized by eating privately to conceal being seen, may reflect eating- and/or body-related shame, be associated with depression, and correlate with binge eating, which predicts weight gain and eating disorder onset.
Even in toddlers, a negative self-concept has been found to be associated with depression.
