Search

Insulin, glucose, and large neutral amino acids (LNAA) were studied in 10 patients with anorexia nervosa, 13 patients with bulimia nervosa, and 15 healthy controls. Blood samples were collected at hourly intervals during the day and at two-hour intervals during the night over a 24-hour period. Ad libitum caloric and relative carbohydrate intake was significantly reduced in the anorectic and bulimic patients. Elevated concentrations of beta-hydroxybutyric acid (BHBA) were seen in the bulimic group, and low triiodothyronine (T3) concentrations in the anorectic group. Mean plasma glucose and insulin concentrations were significantly lowered in both groups. The tryptophan (Trp) to LNAA ratio was reduced in anorectic, but not in bulimic patients. These findings suggest that Trp influx into the brain is reduced in anorectic patients, possibly impairing central serotonergic function.

A correlation between dietary restraint and the occurrence of binge eating has been convincingly shown in several investigations. However, the mediating mechanisms have not yet been elaborated in detail nor linked to empirical evidence. This theoretical gap is addressed in the following. After a short review of behavioral and metabolic correlates of dietary restraint, potential effects of restrained eating on the psychophysiological regulation of food intake are described. These effects may lead to the disruption of intake regulation and therefore can be regarded as direct causes of binge eating.

The hypothesis that patients with bulimia nervosa and restrained eaters exist on a simple continuum of psychopathology was tested in 60 Ss (20 bulimics, 20 restrained eaters, 20 unrestrained eaters). Regarding measures related to dieting behavior and physical appearance, the restrained eaters differed significantly from unrestrained eaters and were similar to bulimic patients except for level of psychopathology. The restrained eaters could not be distinguished from the unrestrained eaters with regard to measures representing interoceptive perception, depression, self-esteem, and fears about interpersonal relationships. On these traits, bulimic patients could be clearly distinguished from the normal Ss. The results support a 2-component model of the psychopathology of bulimia nervosa.

Gonadotrophins and gonadal hormones were studied during the menstrual cycle or during 5 weeks when no cycles occurred in 15 patients who were diagnosed as having bulimia by DSM III criteria. Nine healthy age-matched women served as controls. Based on plasma oestradiol (E2) values patients were divided into two groups. Group I (n = 8) did not show E2 increases greater than 444 pmol/l indicating that no follicular development took place. Group II showed normal follicular hormone production during the follicular phase but impaired progesterone (P4) levels during the luteal phase. Studies of episodic gonadotrophin secretion during the follicular phase revealed low average LH and FSH values and reduced amplitude but no significant changes of frequency in group I. Our data indicate that impaired follicular maturation as seen in about half of the bulimic patients is caused by impaired gonadotrophin secretion.