Metabolic profile in Prader-Willi syndrome patients followed at a single expert center of rare endocrine diseases

Prader-Willi syndrome (PWS) is a rare imprinting disorder characterized by typical dysmorphic features, lack of satiety, infantile hypotonia, and later morbid obesity with complications, short stature, hypogonadotropic hypogonadism, skeletal and psychiatric problems. From the literature, it is well known that patients with PWS have a more favorable metabolic pattern than healthy controls. The aim of the study is to assess the metabolic profile of PWS patients followed at an Expert Center for Rare Endocrine Diseases compared with healthy controls and to look for relations between components of the metabolic syndrome (MetS), adipokines, and the compartments of body composition (BC—lean and fat mass). The current study is a cross-sectional evaluation of 25 patients with Prader–Willi syndrome (mean age 11.3 ± 8.2 years), with a total of 183.6 patient-years of regular follow-up (from the first visit to the center to the data collection cutoff date), compared with 24 age-, sex-, and BMI-matched healthy controls (mean age 11.3 ± 3.9 years). Each participant underwent anthropometric measurements, physical examination, biochemical and hormonal blood sampling, and whole-body DXA scan. Statistical analysis (SPSS 15.0 statistical package, Chicago, IL, USA) was performed to assess the relations between the metrics in the PWS group compared with controls. Patients with PWS showed a better profile of glucose homeostasis with significantly lower serum insulin concentration and calculated HOMA-IR index compared with the controls (p < 0.05). Taking into consideration age, sex, and body mass index (BMI) in the PWS group, the analysis showed strong positive correlations between waist circumference (WC) and systolic blood pressure (SBP) (r = 0.864, p < 0.001), and WC and diastolic blood pressure (DBP) (r = 0.534, p = 0.033). Partial correlation analysis with respect to age, sex, and pubertal development found significant positive WC correlations with insulin (r = 0.796, p = 0.006), HOMA-IR (r = 0.697, p = 0.025), LDL-cholesterol (r = 0.735, p = 0.002), uric acid (r = 0.735, p = 0.002), CRP (r = 0.600, p = 0.023), and leptin (r = 0.730, p = 0.005). Strong negative correlations existed between WC and SHBG (r = -0.772, p = 0.002) and HMW adiponectin (r = -0.998, p = 0.044). Additionally, a negative correlation of HMW adiponectin and SBP was demonstrated. 88% of the patients were treated with recombinant human growth hormone (rhGH). Bone mineral density adjusted for height (BMD/height) was significantly lower in patients with PWS (p < 0.05) compared with healthy controls. The analysis did not reveal significant relationships between BC compartments and metabolic and auxological parameters in the PWS group. Our study confirms that patients with PWS have a favorable metabolic profile compared with healthy controls matched by age, sex, and BMI. Syndromic participants who manifest greater accumulation of abdominal adipose tissue have a higher risk of hemodynamic changes and metabolic disturbances predictive of the development of cardiovascular diseases (CVD) in adulthood. WC could serve as a predictive marker for detecting higher metabolic risk in this syndromic group of patients, and both WC and HMW adiponectin for hypertension. In the future, on this basis, we could possibly implement both of these metrics in clinical practice.