Does Basal Morning Luteinizing Hormone (bLH) Predict Central Precocious Puberty (CPP) in Girls?

Background and Objectives: bLH is considered an excellent biochemical predictor of CPP. However, its utilization in clinical practice shows some uncertainties. This study aims to evaluate the diagnostic power of bLH and propose a diagnostic algorithm for CPP. Materials and Methods: We conducted a monocentric cohort retrospective study evaluating all females referred for suspicion of CPP between 1 January 2017 and 31 December 2020 who underwent a GnRH test. Auxological, hormonal, and instrumental data were collected, including pelvic ultrasonography and bone age (BA) assessment. Simple linear regression, t-test, and ROC tests were utilized to study the diagnostic value of basal hormone levels. Two hundred thirteen girls were included in the study. They were subdivided into two groups according to the results of the GnRH test: Group 1, with LH peak > 5 IU/L (pubertal) and 79 patients (37%), and Group 2, with an LH peak ≤ 5 IU/L (prepubertal) and 134 patients (63%). Results: The ROC curve showed that bLH level > 1.5 Ul/L best predicts a pubertal response to the GnRH test (AUC 0.8821, accuracy 82%), with low sensitivity (34%). The multivariate analysis found that bLH > 0.5 IU/L, basal FSH (bFSH) > 3.5 IU/L, bLH/bFSH ratio > 0.16, BA advancement > 1.7 years, uterine volume > 3.6 mL, longitudinal uterine diameter > 41 mm, and the presence of endometrial rhyme were significantly associated with a pubertal response at the GnRH test. An algorithm based on these features was created, and its application would reduce the number of GnRH tests by 34%. Overall, 96.2% of Group 1 patients reached the LH peak at the 30th minute of the GnRH test, supporting the hypothesis that the GnRH test duration could be reduced to 30 min. Conclusions: Morning bLH > 1.5 IU/L could be carefully used as a diagnostic predictor of CPP. The GnRH test, even reduced to 30 min, could be reserved for girls who show low intermediate morning bLH and specific clinical signs of pubertal development.

Gender differences in weight gain during lockdown due to COVID-19 pandemic in adolescents with obesity.

BACKGROUND AND AIM: Lockdown due to COVID-19 pandemic has forced a decrease in physical activity (PA), an increase in sedentary behavior (SB) and a possibly worsening of fat accumulation in already obese subjects. The aim of this study was to investigate how social restriction may have contributed to weight changes in adolescents with obesity. Secondary aim was to evaluate possible parameters influencing weight changes. METHODS AND RESULTS: Parameters of 51 obese adolescents were compared between two visits: within 2 months before 8 March, start of lockdown, and within 40 days after the end of it. RESULTS: Mean weight gain during lockdown was 2.8 ± 3.7 kg (p < 0.001). Weight increase was higher in males than in females (3.8 ± 3.4 kg vs 1.2 ± 3.7 kg, p = 0.02). The hours dedicated to SB increased (+2.9 ± 2.8 h/day; p < 0.001) while the hours of PA decreased (-1.0 ± 1.6 h/week; p < 0.001). Males spent more hours in SB than females (+3.8 ± 2.7 h/day vs +1.5 ± 2.5 h/day; p = 0.003). There were minor changes in diet during lockdown. The most significant variables influencing both delta BMI and waist/height ratio increase were hours devoted to SB during lockdown and differences in mild and moderate PA before and after lockdown. CONCLUSIONS: Obese adolescents showed a worsening of obesity during lockdown, with males mainly affected, mainly due to a reduced mild PA and increased hours spent in SB.