Hyperendorphinemia in obesity is not related to the affective state

In seventy-two patients affected by hyperphagic obesity and forty age-matched, normal weight volunteers we performed a psychological assessment, through various mental tests, and evaluated the beta-endorphin (B-Ep), ACTH and cortisol circulating levels, in basal condition and following an overnight short dexamethasone suppression test (DST). The hormones were measured by radioimmunoassay either directly in the serum (cortisol) and the plasma (ACTH), or after affinity gel column chromatography (B-Ep). In obese subjects B-Ep levels in basal conditions were four times greater than in normal weight controls and showed significantly less reduction after DST. ACTH and cortisol levels, in contrast, were in the normal range and were suppressed following dexamethasone as was also true in the control group. Psychological evaluation on M.M.P.I. (Minnesota Multiphasic Personality Inventory) revealed a trend toward hypochondria, depression, hysterias, psychoasthenia and schizophrenia. However, no significant correlation has been found between M.M.P.I. clinical scale scores and circulating levels of B-Ep and cortisol either in basal conditions or after DST. In conclusion, these data do not support the hypothesis that abnormalities of the hypothalamus-pituitary-adrenal axis in hyperphagic obesity are related to affective disorders.