Neuropsychiatric aspects in a rare case of hypothalamic obesity

Abstract

A 22-year-old woman presented with weight gain (class I obesity), oligomenorrhea, impaired vision and altered concentration. With suspected craniopharyngeoma she was treated with transcranial surgery; in fact for a suprasellar haemangioma. Post-operatively, she still presented an alteration in appetite with hyperphagia and excessive weight gain up to class III obesity. This syndrome is described as "hypothalamic obesity" and results from any damage to the ventromedial hypothalamus potentially leading to autonomic imbalance, hyperphagia, insomnia and pituitary deficiency. Endocrine diagnostics revealed panhypopituitarism in our patient. Furthermore, she suffered from anhidrosis and an altered probably sympathetic thermoregulation with an increase of body temperature up to 40 degree C during low physical activity, which makes it nearly impossible to loose weight through training programs. Obesity and hyperinsulinemia led to development of diabetes mellitus. Lifestyle intervention is described essentially useless in this syndrome. Appropriate hormone replacement therapy and strict caloric reduction showed slight effect on weight loss in her case. Bariatric surgery is still planned for the future, although there are no data on metabolic outcome and long-term results in patients with hypothalamic syndrome. Further diagnostic procedures showed a central sleep apnea syndrome with hypoxemia, alteration in cognition, learning and memory processes as well as an organic affective disorder with loss of motivation and increased daytime sleepiness. Only a few numbers of studies have investigated neuropsychological deficits and development of functional capacities in patients with hypothalamic obesity syndrome, mainly due to craniopharyngeoma during childhood, so far. Limited numbers of therapeutic trials yield no standard pharmacological intervention. There is evidence that deficits in hypothalamic-pituitary-axis itself lead to alteration of neuropsychiatric functions and obesity is known to be associated with affective disorders like depression, additionally. Therefore, patients with hypothalamic syndrome seem to be at great risk of developing psychiatric diseases with impaired quality of life. Besides effective substitution therapy for hypopituitarism and strict life-style interventions to control weight, one should be aware of possible neuropsychiatric disorders and included psychotherapy if necessary.