Relative skeletal maturity status affects injury burden in U14 elite academy football players

Maturation progresses at different times and at different rates between individuals. Thus, differences in maturity status exist among players in the same chronological age-based category, especially in U14 players. The purpose of this prospective study was to describe injury burden according to the relative skeletal maturity status in U14 elite academy football players. From 2011 to 2020 injuries and individual exposure (training and match) were prospectively recorded in 183 male U14 players. Skeletal age (SA) was assessed using the Tanner-Whitehouse 2 method. Relative skeletal maturity status [SA minus chronological age (CA)] was classified as follows: early (SA-CA > 0.5), on-time (SA-CA ± 0.5) and late (SA-CA < -0.5). Overall and specific injury burden (days lost/1000h) and rate ratios for comparisons between groups were calculated. Overall injury burden was 2.8-times higher (3.6-times in training) in early maturers compared with late maturers. Growth-related injuries were the most burdensome injuries in all three groups, but significant differences were not found between groups. Muscle injuries were 4-times more burdensome in early maturers compared with on-time and late maturers. Besides, joint/ligament injuries were 7- and 12- times less burdensome in late maturers than in on-time and late maturers, respectively. Significant differences between groups in overall and specific injury burden were not found in matches. Our results showed different injury patterns in U14 early, on-time and late maturers. Hence, monitoring maturity seems crucial to detect potential injuries that cause the greatest disruption, and facilitate design of targeted injury prevention programs.

SUN-494 A Case of Hyperthyroidism with Multiple Recurrences of Neutropenia After Stopping Methimazole

Background: The adverse effects of methimazole usually occur in the first 6 months of treatment and they usually are dose dependent. The most severe ones are hepatotoxicity and agranulocytosis, the frequency of the latter is 0.1-0.5% and with a high mortality rate.

Clinical case: A 15-year-old female patient was sent to Endocrinology in May 2017 because of a 4-month history of tremor, palpitations and heat intolerance. Lab tests: WBC: 6,800, neutrophils: 36% (2,448/l), TSH: < 0.06 uU/ml (0.27- 4.7), T4: > 25 ug/dl (4.5 -12), FT4: >7.7 ng/dl (0.93 -1.7), TPO >1,000 UI/ml (<10), TRAb > 40 UI/L (<1.75) which confirmed Graves’ disease. Propranolol 80 mg/day and methimazole 30 mg/day were prescribed. Two months later methimazole dose was increased to 40 mg/d, hematologic lab test was normal. Seven months after starting methimazole the patient presented with febrile neutropenia, methimazole was stopped, methylprednisolone 20 mg/d was prescribed and we increased propranolol to 120 mg/d, neutropenia improved. A month after the first episode of neutropenia, she presented a second episode with a pharyngeal infection, WBC: 6,300, neutrophils: 1%. In December 2017 radioiodine therapy was performed: 15 mCi. Hyperthyroidism was not resolved, she continued with methylprednisolone 20 mg/d and propranolol 120 mg/d, and 6 drops/d of Lugol solution was prescribed. From December 2017 to July 2018, the patient presented 9 episodes of febrile neutropenia, she had a good response to Granulocyte-colony stimulating factor. Serology tests for CMV, VDRL, HIV, Epstein Barr, Toxoplasmosis, hepatitis B and C were all negative. Lab tests for rheumatologic diseases: rheumatoid factor, C3 and C4, electrophoretic proteinogram, antiestreptolysin O, anti-DNA, ANA, anti-Ro/SSA, anti-La/SSB were all negative, and immunoglobulins were normal. Bone marrow aspiration was normal. We could not perform flow cytometry of anti-neutrophil cytoplasmic antibodies (C-ANCA). Hyperthyroidism persisted and a second I-131 treatment was performed (20 mCi) in June 2018. A month later she presented hypothyroidism, levothyroxine was indicated. She continued with episodes of febrile neutropenia until March 2019, 23 months after the diagnosis of hyperthyroidism, 16 months after stopping methimazole and 8 months after having initiated levothyroxine treatment and having normal thyroid levels.

Conclusion: We presented a young female patient with persistent and recurrent neutropenia despite having stopped methimazole, and regardless of her thyroid hormone levels. Although neutropenia usually appears in the first months of treatment, it seldom occurs much later and almost never after stopping the drug. We could not reach an etiological diagnosis of neutropenia, but it is probable that methimazole had triggered an immune-hematological illness associated to Graves’ disease.

MON-432 Symptomatic Pituitary Metastases: A Report of 16 Cases

Introduction: Pituitary Metastases (MTS) are infrequently seen in clinical practice. The incidence ranges from 0.14 to 28%. Breast and lung cancer are the primary sites that most frequently metastasize to sellar region, between the sixth and seventh decades of life. Most cases are diagnosed in patients with advanced malignant disease, however, in 20-30%, symptoms of pituitary involvement can precede the diagnosis of the primary tumor. Objectives: To evaluate symptoms at presentation, hormonal, radiological and histological findings, management and outcome of a series of patients with pituitary MTS. Patients and methods: medical records of 16 patients from eight Endocrine Centers were reviewed. Ten patients had histological confirmation of the pituitary MTS, 6 were not operated, being the diagnostic criteria the presence of sellar mass associated with diabetes insipidus (DI) and / or sudden-onset of neuro-ophthalmological symptoms in patients with confirmed primary neoplasia. Results: The median age was 54 years (range 35-70), 9 women (56.2%). The sites of the primary tumor were: 7 lung (44%), 5 breast (32%), 1 follicular thyroid carcinoma (6%), 1 Hodgkin lymphoma (6%), 1 poorly differentiated carcinoma (6%), and 1 clear cell renal carcinoma (6%). The median time between the diagnosis of the primary neoplasm and the occurrence of the pituitary MTS was 12 months (range: 3-120). In 9 patients (56.2%), the diagnosis of the primary neoplasm was made after the finding of the symptomatic sellar mass. DI was found in 14 patients (87.5%), adenohypophyseal deficit in 12 (75%), visual disorders in 10 (62.5 %), headache in 6 (37.5%) and cranial nerve deficits in 6 (37.5%). In 68.7% (11 patients), other MTS were detected. Fifteen patients were evaluated by MRI and one by CT: 13 (81.3%) harbored supra / parasellar masses, and the remaining 3 had lesions limited to the pituitary gland, with stalk thickening and lack of spontaneous neurohypophysis hyperintensity in 2 of them. In all cases diffuse gadolinium uptake was present. Fourteen patients died (87.5%), with a median survival time of 6,5 months (range: 1-36); the remaining 2 are still alive with a follow-up period of 4 and 12 months respectively. Conclusions: In this series of 16 patients with pituitary MTS, the most frequent primary neoplasms were lung and breast. Median age was lower than in published series. DI was the most common condition at presentation, followed by hypopituitarism and visual disorders. The short survival was related to the extent of the disease at the time of diagnosis. In more than half of the cases the diagnosis of primary neoplasia was made through the symptomatic pituitary mass. In the presence of a pituitary lesion with diffuse gadolinium uptake, associated with DI and / or acute visual deficit, pituitary MTS should be suspected even in patients without a history of oncological disease.

SUN-448 Giant Prolactinomas: A Follow-Up of 25 Years with Dopamine Agonists

Giant prolactinomas are tumors with a large size > 4 cm and/or prolactin levels higher than 3000 ng/ml and/or highly invasive growth. Today dopamine agonists, mainly cabergoline (CAB), are the first-line choice in the treatment of these tumors. Objective: To assess the efficacy, safety and long-term follow-up of patients with giant prolactinomas treated with dopamine agonists. Methods: We retrospectively reviewed the clinical records of 20 patients with giant prolactinomas. Mean age at diagnosis was: 45.2 ± 18.9 years, 75% men. The median follow-up time was 9.05 years (1.5-25.1). At diagnosis the median prolactin level was 6,545 ng/ml (3,238-15,325), the mean maximum diameter of the tumors was 4.60 ± 1.35 cm. At diagnosis, headaches were present in 55% and hypogonadism in 85% of patients; 80% had invasive tumors and 75% had visual field (VF) impairment. Since the diagnosis, almost all patients were treated with CAB except 2, one with bromocriptine LAR and the other one with oral bromocriptine, both were switched to CAB afterwards. Results: Seventy percent of patients normalized prolactin levels, this was achieved in a median time of 7.5 months (2-26) and with a mean dose 2.14 ±1.19 mg/week of CAB. Fifty-four percent of patients reached this prolactin nadir in 2-4 months with a maximum dose < 2 mg/week. The median prolactin level in the last visit was 31.23 ng/ml (12-147). Ninety percent of patients decreased prolactin level during follow-up: 50% normalized prolactin, 25% remained with a mild hyperprolactinemia, 25% with significant hyperprolactinemia. Ninety-five percent of tumors reduced their volume, 60% evolved to empty sella, the remaining achieved a mean decrease of 3.75 cm compared to the initial size (82% of average reduction compared to the initial diameter). The VF remained normal in patients in whom it was not affected, except in 1 whose VF deteriorated because of chiasmatic ptosis; in the patients who presented VF involvement: 47% improved, 40% remained unchanged and 13% worsened. The complications during the follow-up were: Cerebrospinal fluid leak in 2 patients, chiasmatic ptosis in 1 with VF impairment, intra-tumoral hemorrhage in 1. In the follow-up only 1 patient required surgery; 4 patients died, 2 because of the tumor. In 3 (15%) patients CAB was stopped at 96-180-264 months after treatment was initiated, but in all of them CAB was reinitiated due to symptomatic hyperprolactinemia. In 16 patients the treatment could never be discontinued. Conclusions: CAB was effective in the treatment of giant prolactinomas reducing tumor size (some of them evolved to empty sella) and prolactin levels in most patients, with low-moderate doses of CAB and very few complications. In our experience of 25 years of follow-up, we have not had any patients without treatment.

Serum adiponectin is associated with body composition and cognitive and psychological status in older adults living in long-term nursing homes

Frailty is a geriatric syndrome characterized by decreasing functional reserves and increasing vulnerability to falls, injuries and declining health, leading to dependence upon caregivers. Frailty is associated not only with physical decline, but also with cognitive and psychological impairments in aging people. Higher serum adiponectin concentration has been linked to better performance on frailty measures but also to worse cognitive status. Nonetheless, several studies have proposed adiponectin as a frailty biomarker. To further delineate the relationship between adiponectin serum levels and frailty-related parameters, we studied a population of 112 long-term nursing home residents (aged 84.9 ± 6.7) and analyzed their serum adiponectin levels in conjunction with frailty-related parameters including body composition, physical fitness, cognitive function, psychological parameters and quality of life. Frailty was assessed following the Fried Frailty Criteria, the Clinical Frailty Scale and the Tilburg Frailty Indicator. In women, higher serum adiponectin levels were associated with lower body weight, body mass index, body fat mass, fat mass/height², lean mass, lean mass/height² and smaller waist circumference and hip circumference (p < 0.05). In men, the association was positive (p < 0.05) between serum adiponectin and percentage of fat mass and negative between serum adiponectin and percentage of lean mass. Interestingly, in men, better cognitive function was inversely related to adiponectin (p < 0.05) while decreased anxiety was linked to a higher concentration of adiponectin in women (p < 0.05). According to the Tilburg Frailty Indicator, frail men had lower levels of adiponectin than those who were not frail (p < 0.05). Variables that predicted adiponectin concentration in multiple regression models were different for women and men. In women, lean mass and anxiety were independent negative predictors of blood adiponectin (β = -0.363, p = 0.002; β = -0.204, p = 0.067, respectively). In men, the Montreal Cognitive Assessment (MOCA) test was the only parameter to remain significant in the regression model (β = -439, p = 0.015). The results of our study show that adiponectin is linked to body composition, cognitive function and anxiety in long-term nursing home residents with differential relationships by sex. Further studies should be conducted to determine whether adiponectin is a valid and reliable frailty biomarker.

A comparison of injuries in elite male and female football players: A five-season prospective study

The aim was to compare the epidemiology of injuries between elite male and female football players from the same club. Injuries and individual exposure time in a male team and a female team, both playing in the Spanish first division, were prospectively recorded by the club's medical staff for five seasons (2010-2015) following the FIFA consensus statement. Total, training, and match exposure hours per player-season were 20% higher for men compared to women (P<.01). Total, training, and match injury incidence were 30%-40% higher in men (P≤.04) mainly due to a 4.82 (95% confidence interval [CI] 2.30-10.08) times higher incidence of contusions, as there were no differences in the incidence of muscle and joint/ligament injuries (P≥.44). The total number of absence days was 21% larger in women owing to a 5.36 (95% CI 1.11-25.79) times higher incidence of severe knee and ankle ligament injuries. Hamstring strains and pubalgia cases were 1.93 (95% CI 1.16-3.20) and 11.10 (95% CI 1.48-83.44) times more frequent in men, respectively; whereas quadriceps strains, anterior cruciate ligament ruptures, and ankle syndesmosis injuries were 2.25 (95% CI 1.22-4.17), 4.59 (95% CI 0.93-22.76), and 5.36 (95% CI 1.11-25.79) times more common in women, respectively. In conclusion, prevention strategies should be tailored to the needs of male and female football players, with men more predisposed to hamstring strains and hip/groin injuries, and women to quadriceps strains and severe knee and ankle ligament injuries.

Longitudinal field test assessment in a Basque soccer youth academy: a multilevel modeling framework to partition effects of maturation

The purpose of the study was to examine the effect of age on short-term performance indicators applying multilevel regression modeling, and whether changes induced by age were affected by maturation. The study applied a mixed longitudinal approach with 8 measurement points over a period of 4 years. Anthropometry, predicted adult stature, countermovement jump, 15-m sprint and agility test from 38 under-11 young soccer players were considered. Early maturing players were 3% taller compared to late maturers. A substantial effect of age was present in all performance indicators (P<0.05). Parameters showed improvements in performance, even when accounting for interindividual variation in somatic maturity. Vertical jump tended to be stable in early maturers during the first year, presenting an exponential increase thereafter (16%, P<0.05). Additionally, early maturing boys had lower vertical jump scores but a substantial higher rate of development with age (3% per year). Performance tends to plateau during the first 3 years following the improvements in agility (9.1%, P<0.05). In the running tests, early maturers had better performances (19%, P<0.05), while a higher rate of improvement of 1% was observed for the late maturers. Young soccer players should be expected to have substantial improvements in short-term performance, influenced by independent variation between players in maturity status.

OBLA is a better predictor of performance than Dmax in long and middle-distance well-trained runners

AIM

The main purpose of this study was to investigate if the lactate threshold estimated by the maximal deviation method (LTDmax) and the onset of blood lactate accumulation speed (LTOBLA) are good correlates of middle- and long-distance running performance in well-trained endurance runners.

METHODS

Eleven long- and eleven middle-distance runners participated in this study. All participants completed a maximal incremental running test on a treadmill to determine maximal physiological variables and velocities corresponding to LTDmax and LTOBLA (4 mmol·L-1 of lactate concentration). The relationships between LTDmax, LTOBLA and the best 10-km (S10km) and 3-km (S3km) race pace were analyzed in the long- and middle distance runners, respectively.

RESULTS

The velocities for LTDmax and LTOBLA were 17.0±0.7 km·h-1 and 17.5±1.3 km·h-1 for the long-distance runners and 16.9±1.1 km·h-1 and 17.4±1.3 km·h-1 for the middle-distance runners. A positive linear relationship was found between LTDmax and S10km (r=0.873, P<0.001), as well as between LTOBLA and S10km (r=0.919, P<0.001) in the long-distance runners. Similarly, LTDmax and LTOBLA were significantly correlated with S3km in the middle-distance runners (r=0.825, P<0.01 and r=0.849, P<0.001, respectively).

CONCLUSION

These results indicate that both LTOBLA and LTDmax are highly associated to running performance according to S10km and S3km in well-trained long- and middle-distance runners. Thus, we conclude that competitive middle- and long-distance athletes may find these measures useful to monitor running performance within 3 weeks of laboratory testing.

Interaction effects of stride angle and strike pattern on running economy

This study aimed to investigate the relationship between stride angle and running economy (RE) in athletes with different foot strike patterns. 30 male runners completed 4 min running stages on a treadmill at different velocities. During the test, biomechanical variables such as stride angle, swing time, contact time, stride length and frequency were recorded using an optical measurement system. Their foot strike pattern was determined, and VO2 at velocities below the lactate threshold were measured to calculate RE. Midfoot/forefoot strikers had better RE than rearfoot strikers (201.5±5.6 ml · kg(-1) · km(-1) vs. 213.5±4.2 ml · kg(-1) · km(-1)respectively; p=0.019). Additionally, midfoot/fore-foot strikers presented higher stride angles than rearfoot strikers (p=0.043). Linear modelling analysis showed that stride angle is closely related to RE (r=0.62, p<0.001) and that the effect of stride angle on RE was different in the 2 groups. From an arbitrary value of 4°, a rearfoot strike pattern is likely to be more economical, whereas at any lower degree, the midfoot/forefoot strike pattern appears to be more desirable. A biomechanical running technique characterised by high stride angles and a midfoot/forefoot strike pattern is advantageous for a better RE. Athletes may find stride angle useful for improving RE.

Differences in ground contact time explain the less efficient running economy in north african runners

The purpose of this study was to investigate the relationship between biomechanical variables and running economy in North African and European runners. Eight North African and 13 European male runners of the same athletic level ran 4-minute stages on a treadmill at varying set velocities. During the test, biomechanical variables such as ground contact time, swing time, stride length, stride frequency, stride angle and the different sub-phases of ground contact were recorded using an optical measurement system. Additionally, oxygen uptake was measured to calculate running economy. The European runners were more economical than the North African runners at 19.5 km · h(-1), presented lower ground contact time at 18 km · h(-1) and 19.5 km · h(-1) and experienced later propulsion sub-phase at 10.5 km · h(-1),12 km · h(-1), 15 km · h(-1), 16.5 km · h(-1) and 19.5 km · h(-1) than the European runners (P < 0.05). Running economy at 19.5 km · h(-1) was negatively correlated with swing time (r = -0.53) and stride angle (r = -0.52), whereas it was positively correlated with ground contact time (r = 0.53). Within the constraints of extrapolating these findings, the less efficient running economy in North African runners may imply that their outstanding performance at international athletic events appears not to be linked to running efficiency. Further, the differences in metabolic demand seem to be associated with differing biomechanical characteristics during ground contact, including longer contact times.

Aetiology of running-related gastrointestinal dysfunction. How far is the finishing line?

30 to 65% of long distance runners experience gastrointestinal (GI) symptoms related to exercise. Several hypotheses have been postulated; however, the aetiology and pathophysiology are far from clear. The mechanical effect of running on the viscera must be involved in the development of GI symptoms in this sport. Reduction of splanchnic blood flow due to visceral vasoconstriction is another widely supported theory; nevertheless, it does not explain many of the clinical findings. Examination of the GI tract during exercise is a difficult task, and measurements of both orocaecal and whole-gut transit time have shown equivocal results. GI hormones, and especially prostaglandins, may be of crucial importance for the production of symptoms. Intestinal absorption, secretion and permeability may also be altered during exercise, provoking intestinal dysfunction. Factors such as stress, diet, dehydration, infections and other factors need to be analysed in order to present a global view of the hypotheses regarding the aetiology of this common and often overlooked problem.