Heading Frequency and Risk of Cognitive Impairment in Retired Male Professional Soccer Players.

Importance: Although professional soccer players appear to be at higher risk of neurodegenerative disease, the reason remains unknown. Objective: To examine whether heading frequency is associated with risk of cognitive impairment in retired professional soccer players. Design, Setting, and Participants: A UK nationwide cross-sectional study was conducted between August 15, 2020, and December 31, 2021, in 459 retired male professional soccer players older than 45 years and registered with the Professional Footballers' Association or a League Club Players' Association. Exposure: Data on heading frequency in 3 bands-0 to 5, 6 to 15, and more than 15 times per match or training session and other soccer-specific risk factors, such as player position and concussion-were collected through a self-reported questionnaire. Main Outcomes and Measures: Cognitive impairment was defined using the Telephone Interview for Cognitive Status-modified as scores of less than or equal to 21. Hopkins Verbal Learning Test, verbal fluency, and independent activities of daily living were also assessed. Test Your Memory and physician-diagnosed dementia/Alzheimer disease were self-reported via the questionnaire. Adjusted odds ratios (AORs) with 95% CIs were calculated. Results: Of 468 retired male professional soccer players who completed questionnaires (mean [SD] age, 63.68 [10.48]; body mass index, 27.22 [2.89]), 459 reported heading frequency: 114 headed 0 to 5 times, 185 headed 6 to 15 times, 160 headed more than 15 times per match, and 125 headed 0 to 5 times, 174 headed 6 to 15 times, and 160 headed more than 15 times per training session during their careers. The prevalence of cognitive impairment was 9.78% (0-5 times), 14.78% (6-15 times), and 15.20% (>15 times) per match (P = .51). Compared with players reporting 0 to 5 headers per match, the AORs were 2.71 (95% CI, 0.89-8.25) for players reporting 6 to 15 headers per match and 3.53 (95% CI, 1.13-11.04) for players reporting more than 15 headers per match (P = .03 for trend). Corresponding AORs for heading frequency per training session were 2.38 (95% CI, 0.82-6.95) for those reporting 6 to 15, and 3.40 (95% CI, 1.13-10.23) for those reporting more than 15 in comparison with those who reported 0 to 5 (P = .03 for trend). Concussion involving memory loss was also associated with a greater risk of cognitive impairment (AOR, 3.16; 95% CI, 1.08-9.22). Similar results were observed with other cognitive tests and self-reported physician-diagnosed dementia/Alzheimer disease. Conclusions and Relevance: The findings of this study suggest that repetitive heading during a professional soccer career is associated with an increased risk of cognitive impairment in later life. Further study is needed to establish the upper threshold for heading frequency to mitigate this risk.

Cognitive Impairment and Self-Reported Dementia in UK Retired Professional Soccer Players: A Cross Sectional Comparative Study.

BACKGROUND: Previous studies based on death certificates have found professional soccer players were more likely to die with neurodegenerative diseases, including dementia. Therefore, this study aimed to investigate whether retired professional male soccer players would perform worse on cognitive tests and be more likely to self-report dementia diagnosis than general population control men. METHODS: A cross-sectional comparative study was conducted between August 2020 and October 2021 in the United Kingdom (UK). Professional soccer players were recruited through different soccer clubs in England, and general population control men were recruited from the East Midlands in the UK. We obtained self-reported postal questionnaire data on dementia and other neurodegenerative diseases, comorbidities and risk factors from 468 soccer players and 619 general population controls. Of these, 326 soccer players and 395 general population controls underwent telephone assessment for cognitive function. RESULTS: Retired soccer players were approximately twice as likely to score below established dementia screening cut-off scores on the Hopkins Verbal Learning Test (OR 2.06, 95%CI 1.11-3.83) and Verbal Fluency (OR 1.78, 95% CI 1.18-2.68), but not the Test Your Memory, modified Telephone Interview for Cognitive Status, and Instrumental Activities of Daily Living. Analyses were adjusted for age, education, hearing loss, body mass index, stroke, circulatory problems in the legs and concussion. While retired soccer players were younger, had fewer cardiovascular diseases and other morbidities and reported healthier lifestyles, 2.8% of retired soccer players reported medically diagnosed dementia and other neurodegenerative disease compared to 0.9% of controls (OR = 3.46, 95% CI 1.25-9.63) after adjustment for age and possible confounders. CONCLUSIONS: UK male retired soccer players had a higher risk of performing below established cut-off scores of dementia screening tests and were more likely to self-report medically diagnosed dementia and neurodegenerative diseases, despite having better overall physical health and fewer dementia risk factors. Further study is needed to determine specific soccer-related risk factors.

Systemic Interleukin-6 Response after Intravesical Instillation of Bacillus Calmette-Guérin and Mitomycin C in Superficial Bladder Cancer.

Interleukin-6 (IL-6) is proposed to play a significant role in pathogenesis of urinary bladder cancer (UBC). This role may be influenced by chemotherapy (mitomycin C; MMC) or immunotherapy (Bacillus Calmette-Guérin; BCG). A case-control study was conducted to determine IL-6 levels in serum of newly diagnosed cases (NDC) of superficial UBC, as well as in patients treated with MMC or BCG intravesical instillation. A total sample of 111 patients (36 NDC, 45 MMC and 30 BCG) was included, as well as a control group of 107 healthy controls (HC). IL-6 was detected by enzyme-linked immunosorbent assay. Results revealed that median levels of IL-6 were significantly elevated in NDC group (15.8 pg/mL; P<0.001) compared to MMC and BCG groups (7.5 and 5.3 pg/mL, respectively) or HC (4.4 pg/mL); while, there were no significant differences between the latter three groups (MMC, BCG and HC). Receiver operating characteristic curve analysis revealed that IL-6 is a very good predictor of UBC in NDC group versus HC (area under the curve=0.885; 95% confidence interval=0.828-0.942; P<0.001; cut-off value=10.5 pg/mL; Youden index=0.62; sensitivity=80.6%; specificity=81.3%). Logistic regression analysis confirmed this significance and IL-6 was associated with a higher risk of UBC (odds ratio=1.18; 95% confidence interval=1.11-1.26; P<0.001). In conclusion, this study indicated that IL-6 level was upregulated in serum of NDC of UBC. Further, IL-6 level was restored to normal levels after intravesical instillation of MMC or BCG.

Foot and ankle Osteoarthritis and Cognitive impairment in retired UK Soccer players (FOCUS): protocol for a cross-sectional comparative study with general population controls.

INTRODUCTION: Professional footballers commonly experience sports-related injury and repetitive microtrauma to the foot and ankle, placing them at risk of subsequent chronic pain and osteoarthritis (OA) of the foot and ankle. Similarly, repeated heading of the ball, head/neck injuries and concussion have been implicated in later development of neurodegenerative diseases such as dementia. A recent retrospective study found that death from neurodegenerative diseases was higher among former professional soccer players compared with age matched controls. However, well-designed lifetime studies are still needed to provide evidence regarding the prevalence of these conditions and their associated risk factors in retired professional football players compared with the general male population. OBJECTIVES: To determine whether former professional male footballers have a higher prevalence than the general male population of: (1) foot/ankle pain and radiographic OA; and (2) cognitive and motor impairments associated with dementia and Parkinson's disease. Secondary objectives are to identify specific football-related risk factors such as head impact/concussion for neurodegenerative conditions and foot/ankle injuries for chronic foot/ankle pain and OA. METHODS AND ANALYSIS: This is a cross-sectional, comparative study involving a questionnaire survey with subsamples of responders being assessed for cognitive function by telephone assessment, and foot/ankle OA by radiographic examination. A sample of 900 adult, male, ex professional footballers will be recruited and compared with a control group of 1100 age-matched general population men between 40 and 100 years old. Prevalence will be estimated per group. Poisson regression will be performed to determine prevalence ratio between the populations and logistic regression will be used to examine risk factors associated with each condition in footballers. ETHICS AND DISSEMINATION: This study was approved by the East Midlands-Leicester Central Research Ethics Committee on 23 January 2020 (REC ref: 19/EM/0354). The study results will be disseminated at national and international meetings and submitted for peer-review publication.