Adiponectin and ghrelin levels in craniopharyngioma patients

Introduction: Metabolic and endocrine changes in patients with craniopharyngioma are of considerable relevance for the long-term sequelae of this disease, in particular for the development of diabetes and cardiovascular morbidities. In this context, levels of ghrelin – which have been reported to be low in hypothalamic obesity – and adiponectin, an adipocytokinin known to enhance insulin sensitivity, are of major interest.

Methods: In this pilot trial, concentrations of ghrelin, adiponectin, leptin, insulin and glucose were determined in 16 (9 male, 7 female) fasted patients suffering from craniopharyngioma. In addition, the HOMA index was calculated. The mean age was 44.5 years, the mean BMI was 30.8kg/m² in males and 36.6kg/m² in female patients.

Results: In this group of patients, ghrelin levels differed significantly (p<0.01) between men and women, with higher levels in females than in males. We did not find an inverse correlation with age, as has been described previously. Adiponectin levels were significantly (p<0.01) correlated with the HOMA index and were found to significantly increase with age. As could be expected, leptin levels were found to be significantly correlated with BMI, insulin and HOMA index (p<0.01).

Discussion: While there was no clear-cut correlation of ghrelin levels and BMI in this pilot study, these data otherwise clearly support the concept that both ghrelin and adiponectin levels depend on body weight, possibly via regulation by insulin. Extended studies on the differential metabolic consqeunces in different forms of hypothalamic obesity are warranted.