A retrospective analysis of all-cause and cause-specific mortality rates in French male professional footballers.

This study retrospectively compared all-cause and cause-specific mortality in French male professional football players with data from France's national population. Altogether, 6114 individuals born in Metropolitan France or in one of its overseas territories who played at least one competitive match in France's professional football championships between January 1, 1968 and December 31, 2015, were identified and followed up for vital status obtained from a national reference database until December 31, 2015. Data on all-cause and cause-specific mortality were subsequently compared to the expected number of deaths for the national population after standardization for the year, age, and sex. Ratios between observed and expected deaths provided standardized mortality ratios (SMR) along with 95% confidence intervals (95% CI). Linear trends were investigated using the Poisson trend test. Altogether, 662 player deaths were observed. All-cause mortality overall was lower than that of the national population (SMR: 0.69, 95% CI 0.64-0.75). An excess of deaths from dementia was observed in the players (SMR: 3.38, 95% CI: 2.49-4.50) whereas mortality from diseases of the nervous (SMR: 0.64, 95% CI: 0.35-1.08) and cardiovascular systems (SMR: 0.82, 95% CI: 0.70-0.96), and cancer (SMR: 0.67, 95% CI: 0.58-0.76) was lower. Lower overall mortality and that owing to common cardiovascular and cancer-related diseases were reported in French professional football players compared to France's national population. In line with previous studies, however, excess mortality from dementia was observed in the players. Career length was not associated with all-cause or cause-specific mortality. Prospective matched-cohort studies are necessary to identify the neurologic impact of participation in professional football.

Z-scores-based methods and their application to biological monitoring: an example in professional soccer players.

The clinical and biological follow-up of individuals, such as the biological passport for athletes, is typically based on the individual and longitudinal monitoring of hematological or urine markers. These follow-ups aim to identify abnormal behavior by comparing the individual's biological samples to an established baseline. These comparisons may be done via different ways, but each of them requires an appropriate extra population to compute the significance levels, which is a non-trivial issue. Moreover, it is not necessarily relevant to compare the measures of a biomarker of a professional athlete to that of a reference population (even restricted to other athletes), and a reasonable alternative is to detect the abnormal values by considering only the other measurements of the same athlete. Here we propose a simple adaptive statistic based on maxima of Z-scores that does not rely on the use of an extra population. We show that, in the Gaussian framework, it is a practical and relevant method for detecting abnormal values in a series of observations from the same individual. The distribution of this statistic does not depend on the individual parameters under the null hypothesis, and its quantiles can be computed using Monte Carlo simulations. The proposed method is tested on the 3-year follow-up of ferritin, serum iron, erythrocytes, hemoglobin, and hematocrit markers in 2577 elite male soccer players. For instance, if we consider the abnormal values for the hematocrit at a 5% level, we found that 5.57% of the selected cohort had at least one abnormal value (which is not significantly different from the expected false-discovery rate). The approach is a starting point for more elaborate models that would produce a refined individual baseline. The method can be extended to the Gaussian linear model, in order to include additional variables such as the age or exposure to altitude. The method could also be applied to other domains, such as the clinical patient follow-up in monitoring abnormal values of biological markers.

Symptoms of common mental disorders among professional football referees: a one-season prospective study across Europe.

OBJECTIVE: The primary aim of this study was to determine the prevalence and one-season incidence of symptoms of common mental disorders (CMD; distress, anxiety/depression, sleep disturbance, eating disorders, adverse alcohol use) among European professional football referees. A secondary aim was to explore the view of European professional football referees on consequences, support and needs related to these symptoms. METHODS: An observational prospective cohort study with three measurements over a follow-up period of one season (2015-2016) was conducted among central or assistant professional football referees from Belgium, Finland, France, Germany, Norway, Russia, Scotland and Sweden. Using validated questionnaires to assess symptoms of CMD (self-reported and not clinically diagnosed), an electronic questionnaire in English and French was set up and distributed by the eight football federations involved. RESULTS: A total of 391 referees (mean age of 33 years old; mean career duration of 7 years) were enrolled, of which 292 completed the follow-up period. Baseline 4-week prevalence rates were 6% for distress, 12% for anxiety/depression, 9% for sleep disturbance, 19% for eating disorders and 17% for adverse alcohol use. The one-season incidence of symptoms of CMD was 10% for distress, 16% for anxiety/depression, 14% for sleep disturbance, 29% for eating disorders and 8% for adverse alcohol use. CONCLUSION: While symptoms of CMD occur among professional football referees and can influence negatively refereeing performances, the development of specific support measures for referees are needed in order to manage properly these symptoms of CMD.

Bone health during late adolescence: effects of an 8-month training program on bone geometry in female athletes.

OBJECTIVES: This study investigated the short term changes in hip structural parameters in high level adolescent soccers and swimmers. METHODS: Twenty-six girl swimmers (15.9±2 years) and 32 girl soccer players (16.2±0.7 years) were investigated before and after 8 months of training. Fifteen non-active age-matched adolescents were enrolled at baseline to serve as a reference group. The geometric contributions to bone strength in the proximal femur were quantified using the hip structural analysis technique. RESULTS: Eight months of training had increased the bone density in soccer players but not in swimmers. At the total hip, swimmers conserved their baseline low Z-score values while soccers remained above the normal. At the femoral shaft, the cross sectional area had increased for the two groups with a higher magnitude in soccers (3.17% vs 2.31%; P<0.05). The sub-periosteal width had increased in soccer players (P<0.01) but not in swimmers. The Z-score showed an improvement of cross sectional moment of inertia and section modulus at femoral shaft section for soccers (P<0.001), without any change in swimmers. Remarkably, swimmers had improved the Z-score of buckling ratio (P<0.005), while soccers did not. DISCUSSION/CONCLUSION: A season of training for sport characterized by impact had induced significant bone geometry improvement in late adolescent females despite expectations that this period of growth represents a plateau in bone maturation. This study adds to the existing literature describing intensive swimming practice as lacking an osteogenic effect when assessed by dual energy X-ray absorptiometry.

Mitochondrial abnormalities in patients with HIV-HCV co-infection as compared to patients with HCV mono-infection.

INTRODUCTION: Mitochondrial dysfunction is a classic complication of HIV infection and its treatment and has also been reported in hepatitis C virus (HCV)-infected patients. Little is known about interactions between both viruses on mitochondrial metabolism. METHODS: We performed a cross-sectional study of HCV-infected patients who underwent liver biopsy as part of their routine care. Mitochondrial function was assessed by (a) liver morphological (histology) and functional (spectro-photometry) studies, and (b) serum lactate kinetics, oxygen uptake, and anaerobic threshold measurement during standardized incremental exercise. Three predefined groups of patients were compared. RESULTS: Thirty-eight HCV-infected patients were included: 13 not HIV infected (group 1), 7 with HIV co-infection and low nucleoside reverse transcriptase inhibitor (NRTI) exposure (none over the last 2 years; group 2), and 18 with HIV co-infection and high NRTI exposure (group 3). On liver biopsies, respiratory chain complex IV activity was impaired, at 5 (2-7) nmol/min/mg substrates in group 1, 5 (3-8) in group 2, and 8 (2-13) in group 3 (normal values, 20-56). Maximal power output was diminished and anaerobic threshold occurred earlier in HIV-infected patients, regardless of NRTI exposure. CONCLUSION: HCV has deleterious effects on liver mitochondrial metabolism, notably on respiratory chain complex IV. No significant interaction with HIV was observed.

[Knee tendinopathies and sports practice]. / Tendinopathie du genou chez le sportif.

Knee tendinosis are frequent in sports practice. They are often in relation with sports gesture. Chronic patellar tendinosis are found so more often at the specialist's of jump (athletics and collective sports). The tendinopathies of the tensor of the fascia lata are more often diagnosed at the runner's, while the tendinopathies of the biceps or the harmstrings concern more frequently cyclists. The clinical examination allows to precise the sport concerned, to make the diagnosis, and to look for abnormalities of the morphotype or technical errors. Imaging must be envisaged in a second time (ethnography or MRI). The early treatment is mostly medical, including modifications of sports gesture associated with adapted rehabilitation programs.

Daily regulation of serum and urinary hepcidin is not influenced by submaximal cycling exercise in humans with normal iron metabolism.

Hepcidin and hemojuvelin (HJV) are two critical regulators of iron metabolism as indicated by the development of major iron overload associated to mutations in hepcidin and HJV genes. Hepcidin and HJV are highly expressed in liver and muscles, respectively. Intensive muscular exercise has been reported to modify serum iron parameters and to increase hepcidinuria. The present study aimed at evaluating the potential impact of low intensity muscle exercise on iron metabolism and on hepcidin, its key regulator. Fourteen normal volunteers underwent submaximal cycling-based exercise in a crossover design and various iron parameters, including serum and urinary hepcidin, were serially studied. The results demonstrated that submaximal ergocycle endurance exercise did not modulate hepcidin. This study also indicated that hepcidinuria did not show any daily variation whereas serum hepcidin did. The findings, by demonstrating that hepcidin concentrations are not influenced by submaximal cycling exercise, may have implications for hepcidin sampling in medical practice.

Incidence of injuries in elite French youth soccer players: a 10-season study.

BACKGROUND: Research on age-related injury incidence in elite youth soccer is needed to identify high-risk groups. PURPOSE: To investigate the incidence of soccer-related injuries in elite French youth players based at the Clairefontaine Football Center. STUDY DESIGN: Cohort study (Prevalence); Level of evidence, 1. METHODS: Injuries sustained by players in the younger than 14-, 15-, and 16-year-old age groups during 10 seasons were diagnosed and documented by a sports physician according to type, location, severity, the date the injury occurred, and playing position. RESULTS: Altogether, 1152 injuries were documented across all age groups with 69.1% and 30.9% sustained during training and matches, respectively. A total of 4.8 injuries per 1000 hours' exposure time were recorded and 11.2 and 3.9 injuries per 1000 hours for matches and training, respectively. There was no significant difference in injury frequency between age groups. The youngest group sustained more training injuries (P < .05) and osteochondroses (P < .05) and fewer match injuries than did the oldest group. Injury incidence varied throughout the season, peaking in September in all groups. The majority of injuries lasted less than 1 week (60.2%), contusions were the predominant injury type (30.6%, P < .05), and the upper leg was the site most often injured (24.5%, P < .05). CONCLUSION: Those players younger than 14 years incurred more injuries in training and sustained more growth-related overuse disorders. Older players were more often injured during matches. Injury incidence and the frequency of overuse disorders were highest early in the season.

On the interest of computer modelling in the validation of ambulatory measurement of movement disorders in man.

Continuous ambulatory monitoring is a promising technique for objective evaluation of movement disorders in man. Although technological progress make such devices currently available, no validated measurements exist. We propose an original approach to validate instrumental measurements in central neurological diseases, based upon the use of computer modeling of movement disorders. In such an approach, computer simulations of altered movement were used to validate accelerometric-derived measurements in spasticity and Parkinson's disease. We found that some measurements, derived from the frequency power spectrum of distal acceleration at the upper limb, may be suitable for evaluation of some motor disorders, as spasticity, parkinsonian rigidity and related motor disability. Direct applications are expected in ambulatory monitoring of neurological diseases.

Mitochondrial abnormalities in HIV-infected lipoatrophic patients treated with antiretroviral agents.

BACKGROUND: Lipodystrophy is now widely described in HIV infected patients under antiretroviral regimen with important psychological impact. But physiopathology of loss of fat mass is still debated and the role of mitochondrial impairment is not clearly defined. OBJECTIVE: To correlate clinical lipoatrophy (LA) in HIV patients with long-term treatment by nucleoside reverse transcriptase inhibitors (NRTIs) and muscular impairment related to mitochondrial dysfunction. METHODS: Ten consecutive patients with clinical LA and 10 nonlipodystrophic (NLD) individuals on antiretroviral therapy were included. Patients underwent the following investigations: dual-energy x-ray absorptiometry (DEXA) scanning and lactate kinetics during standardized exercise. The mitochondrial respiratory complex activity (III and IV) and histoenzymatic abnormalities (classified as none, mild, or severe) were evaluated on muscle tissue obtained by biopsy in deltoid muscle. RESULTS: Mean NRTI exposure was longer in the LA group than in the NLD group (81 +/- 30 months vs. 59 +/- 15 months), but mean protease inhibitor exposure was identical in both groups. Mean fat mass distribution for leg in the LA and NLD groups was 860 +/- 381 g versus 1895 +/- 999 g, respectively. The lactic acidosis threshold during exercise was reached in the LA group at lower workloads (mean: 45 +/- 17 W in the LA group vs. 68 +/- 11 W in the NLD group), and maximum power output exercise was restricted in LA patients (mean: 115 +/- 30 W vs. 153 +/- 28 W). Total complex activities in muscular tissue were lower in LA patients: the median (range) for complex III was 67 (1-128) versus 112 (28-143), and the median (range) for complex IV was 28 (1-70) versus 42 (1-75). Six patients had severe histoenzymatic abnormalities in the LA group versus none in the NLD group. CONCLUSION: Clinical LA, confirmed by DEXA, in long-term NRTI-treated patients was associated with muscular mitochondrial dysfunction as shown by rapid lactic acidemia increase, impairment of respiratory chain activity for complexes III and IV, and mitochondrial histoenzymatic abnormalities.

A computer model of rigidity and related motor dysfunction in Parkinson's disease.

This work explores the involvement of spinal circuits in the generation of parkinsonian rigidity and related motor dysfunction. A computer model of spinal proprioceptive input processing, derived from previous work on spasticity modeling, was adapted to the simulation of parkinsonian rigidity. Model parameters were varied to generate simulations reproducing experimental data obtained using the pendulum test of the leg in 10 parkinsonian patients and 3 healthy subjects. Convenient reproductions of experimental traces in rigidity were obtained by the combination of a low reflex gain and a decrease in reflex threshold. These findings are consistent with studies reporting an increase of spinal interneuron excitability and proprioception deficits in Parkinson's disease (PD). Moreover, as the threshold parameter was much lowered, our model generated typical features of parkinsonian resting tremor, endorsing the hypothesis of a participation of a spinal oscillator in this disorder. Finally, tuning the reflex gain during simulations of rigidity resulted in the generation of active movement, opening some hypotheses on pathophysiology of motor dysfunction in PD, and notably, of akinesia. More generally, this work accredits the hypothesis of the involvement of an aperiodic, altered supra-spinal motor drive in PD, resulting in spinal dysfunction, through specific descending motor pathways. This may lead to a search for new (spinal) pharmacological targets in PD. It emphasizes further the value of computer modeling in understanding motor control in health and disease.