https://orcid.org/0000-0001-7348-9570
ABSTRACT
Former collision sport athletes may worry and ruminate about their brain health, which might contribute to psychological distress. We hypothesized there would be a strong association between being very worried about this and current psychological distress.
This cross-sectional study examined former elite/professional Australian rugby league players (n = 235; Mean age = 52.37) who completed the Depression, Anxiety, and Stress Scale-21 (DASS-21), Brief Pain Inventory, and Connor-Davidson Resilience Scale. On average, they played 8.65 years of rugby league professionally (SD = 4.68) and had 23.37 years of total lifetime rugby league participation (SD = 5.66).
There were 29.8% who reported being very worried about the possible effects of past concussion(s) on their memory and thinking skills as they get older. There were 29.2% who reported moderate–severe depression, anxiety, or stress on the DASS-21. A logistic regression predicting moderate–severe psychological distress was significant (p < .001, Nagelkerke R2 = 0.37) and revealed that number of lifetime concussions (odds ratio [OR] = 1.01, 95% confidence interval [CI] = 1.00–1.03), lifetime history of depression (OR = 3.20, 95% CI = 1.44–7.14), lower resilience (OR = 0.96, 95% CI = 0.93–0.99), and being very worried about their concussion history (OR = 3.29, 95% CI = 1.49–7.23) were independent predictors. Total years of participation in rugby league, years of participation at the professional level, and life interference due to chronic pain were not associated with psychological distress in the regression analysis.
These results have implications for the psychological health and quality of life of former collision sport athletes. Providing a multimodal approach to treatment, including psychological interventions, prescribed exercise, and medications, might lead to considerable improvement in their psychological health and quality of life.
INTRODUCTION
In a survey of former National Football League (NFL) players, conducted in 2019 and early 2020, more than one-third reported that they were “extremely concerned” about memory problems (36.9%), their thinking skills (37.8%), and developing chronic traumatic encephalopathy (CTE; 39.5%) (Walton et al., 2022). In a different survey of former NFL players, when asked “Do you believe you have chronic traumatic encephalopathy (CTE)?”, one-third (34.4%) answered yes (Grashow et al., 2024). Concerningly, those former NFL players who perceived themselves to have CTE were more likely to report suicidality (25.4%) compared to former NFL players who did not perceive themselves to have CTE (5.0%). Concern about later-in-life brain health clearly is a major issue for the community of former professional American-style football players, and by extension, it might be a concern for some former professional and elite athletes who participated in contact and collision sports in other countries.
Rugby league is a high-intensity collision sport with a large number of tackles per match (Gardner et al., 2017; King et al., 2010) and a relatively high rate of concussions (Gardner et al., 2015). In a prior study, symptoms of depression in former Australian elite and professional rugby league players were not meaningfully associated with their lifetime history of concussions or their number of years of participation at the elite level of the sport, but these depressive symptoms were associated with their current anxiety, stress, resilience, and life interference due to chronic pain (Iverson et al., 2021). In another study with these former rugby league players, depressive symptoms were the strongest predictor of their perceived cognitive decline, suggesting that subjective worsening of cognition in former players might reflect, at least in part, psychological distress (Van Patten et al., 2021). Subjectively perceived cognitive decline in that study was not associated with objectively measured cognitive functioning using neuropsychological tests (Van Patten et al., 2021).
For former collision sport athletes, worry and rumination about their current and future brain health might contribute to psychological distress and reduced quality of life. Psychology researchers consider worry and rumination to be maladaptive emotion regulation behaviors (Aldao et al., 2010) that are associated with, and magnify, difficulties with anxiety (Nolen-Hoeksema, 2000; Sarin et al., 2005), depression (Hong, 2007; Nolen-Hoeksema et al., 1999), and sleep (Clancy et al., 2020; Zagaria et al., 2023). Worry and rumination are often considered to represent negative perseverative cognition about something feared. These thought processes have been associated with perturbations in cardiovascular, autonomic, and endocrine nervous system activity (Ottaviani et al., 2016), which might partially underlie associations between chronic stress and health vulnerabilities (Ottaviani et al., 2016). Worry, rumination, and repetitive negative thinking are associated with worse perceived physical health and subjective cognitive difficulties in older adults (Morse et al., 2024; Schlosser et al., 2020).
Purpose of the Present Study
As part of their participation in a brain health study, former elite/professional rugby league players were asked how worried they were about the possible effects of the concussion(s) they sustained during their career on their memory and thinking skills as they get older. We hypothesized that there would be a strong association between being very worried about this and current psychological distress, after statistically adjusting for lifetime history of concussions, years of participation in collision sports, age, lifetime history of depression, current life interference due to chronic pain, and resilience. If true, this would have implications for treatment strategies designed to reduce psychological distress and promote a better quality of life in former collision sport athletes.
METHOD
Participants
This was an in-person cross-sectional study. This study included former elite-level Australian rugby league players. The operational definition of elite included playing at least one game of first-grade rugby league in the New South Wales Rugby League, Queensland Rugby League, Australian Rugby League, Super League, or National Rugby League (NRL) competitions. A “professional” rugby league club competition was established in Australia in the 1990s. The elite-level club competition has changed names and structure over its 117-season history. It was known as the New South Wales Rugby League (1908–1994), Australian Rugby League (1995–1997), Super League (1997), and/or NRL (1998–present). The Queensland Rugby League (1908–1987) ran a simultaneous state-based elite club competition, but when they successfully bid for a team license, which was granted for the 1988 season in the New South Wales Rugby League competition, this resulted in the New South Wales Rugby League club competition being the only elite level of club rugby league in Australia.
There were two participant recruitment methods. First, club alumni networks distributed study information to their members. Second, direct and indirect referrals were received from two additional sources: the NRL and the Men of League Foundation (now known as the Family in League Foundation). Study information was also distributed via these two sources to their members, which facilitated a self- or family-referral option to enter the research program. Study exclusion criteria were a medical history of neurosurgery and any history of a brain tumor requiring radiation treatment. No subject had an incidental finding of a brain tumor. Women were not included; a professional rugby league competition for women did not exist until recently (i.e., premiership-level competition for women started in Australia in 2018). Participants were recruited between 2012 and 2024. There were 241 former players who completed the study, but six had missing data on the primary independent measure relating to worry about their memory and thinking skills. Therefore, the total sample size for this study was 235.
Participation and Exposure Measures
Concussion history was based on self-report. During the clinical interview, the definition of concussion from the Consensus Statement on Concussion in Sport (41) was provided to the participants, and they were permitted to ask questions to clarify the definition. Next, they reported the number of lifetime sport-related and non-sport-related concussions sustained, and these values were added together to calculate the total number of lifetime concussions per participant. Number of years played at the elite/professional level, number of first-grade games played at the elite/professional level, and the total (lifetime) number of years of rugby league played in their career were also based on self-report.
Participant-reported Outcome Measures.
Depression, Anxiety, and Stress Scale-21
The Depression, Anxiety, and Stress Scale-21 (DASS-21) is a self-report questionnaire assessing symptoms of depression, anxiety, and stress (Henry & Crawford, 2005; Lee et al., 2019; Lovibond & Lovibond, 1995). There are 21 questions, rated on a 4-point dimensional scale, and they evaluate the severity of the three emotional states, depression, anxiety, and stress, over the past 7 days. The items are rated as “0: Did not apply to me at all; 1: Applied to me to some degree, or some of the time; 2: Applied to me to a considerable degree, or a good part of time; or 3: Applied to me very much, or most of the time.” Each DASS-21 subscale (depression, anxiety, and stress) includes seven items. We used cutoff scores for the DASS-21 to identify participants who were experiencing moderate to severe levels of depression, anxiety, or stress. Those cutoff scores were as follows: Depression ≥14, Anxiety ≥10, and Stress ≥19, which are associated with “moderate” or greater levels of distress per the manual (Lovibond & Lovibond, 1996) and applied by past researchers (Mihalopoulos et al., 2014). If a participant was classified as having one or more of these scores in the moderate to severe range, he was identified as having “moderate-severe psychological distress.”
Brief Pain Inventory
The brief pain inventory (BPI) is a widely used test for quantifying pain and life interference due to pain (Chiarotto et al., 2019; Cleeland & Ryan, 1994; Jumbo et al., 2021; Tan et al., 2004). It measures pain severity in the past 24 hr on a dimensional scale, from “none” (0) to “worst imaginable” (10). The total severity score is calculated by taking the average score from the four severity questions. The BPI also evaluates how pain interferes with seven areas of an individual’s life, including: general activity, mood, physical function, relationships, sleep, work, and enjoyment of life. The pain interference score is calculated by taking the average response from the seven scores. We created a binary variable for the BPI pain interference score. Using the distribution of scores from the total sample, we selected the upper-quartile cutoff score to reflect “high pain interference” in the present sample, and this cutoff score was greater than or equal to 3.15. All former players scoring below this cutoff (i.e., 75% of the sample) were classified as having “typical” pain interference.
Connor-Davidson Resilience Scale
The Connor-Davidson Resilience Scale-25 (CD-RISC-25) (Connor & Davidson, 2003; Wojujutari et al., 2024) is a self-report measure of resilience rated over the past year. The CD-RISC-25 contains 25 items, with responses rated on a 5-point Likert-type scale (0 = “not true at all” to 4 = “true nearly all the time”). Total CD-RISC-25 scores range from 0 to 100, with higher scores representing greater levels of resilience.
Semi-Structured Interview
During a semi-structured research interview, former players were asked “how worried are you about the possible effects of the concussion(s) that you sustained during your career, will have on your memory and thinking skills as you get older?” Former players rated their level of worry on a seven-point scale (1 = no worry at all, through to 7 = extremely worried). The response options are illustrated in Fig. 1. The responses were also categorized into low, medium, and high levels of worry based on the following scale: 1–2 (low or “not worried”), 3–5 (medium), and 6–7 (high or “very worried”). Binary groups were formed, with those who rated themselves as 6 or 7 classified as “very worried” and all others classified as “not very worried.”
Ratings of how worried former elite and professional rugby league players are about the possible effects of past concussions on their memory and thinking skills as they age.
Statistical Analyses
Spearman correlations were used to examine bivariate associations among the clinical outcome measures. As described above, binary groups were formed, with those who rated themselves as 6 or 7 classified as “very worried” and all others classified as “not very worried.” Mann–Whitney U tests were used to examine these two groups on participation history, concussion history, pain, mental health, and resilience. For these outcome variables, primary playing position (forwards versus backs) was also examined using Mann–Whitney U tests. Effect sizes were estimated using Hedges’ g. Binary groups were also formed to create moderate–severe psychological distress groups. As described above, if a participant was classified as having one or more of the DASS-21 scores in the moderate to severe range, he was identified as having “moderate-severe psychological distress.” Unadjusted and adjusted associations were examined using binary logistic regressions with moderate–severe psychological distress as the dichotomous dependent variable. The unadjusted odds ratios (ORs) were derived from a series of univariable binary logistic regression analyses. Odds ratios above or below 1.0 with a 95% confidence interval (CI) not including 1.0 reveal predictors that are associated with greater or lesser odds of endorsing moderate–severe psychological distress. A multivariable logistic regression was conducted, including all exposure and clinical variables in the same model. The adjusted ORs are derived from this single multivariable logistic regression analysis. The ORs are interpreted in the same manner as described above, although they reflect the increase in odds of endorsing moderate–severe psychological distress after adjusting for all other variables in the model.
RESULTS
Participants were 241 men who competed in elite or professional rugby league in Australia. There were six subjects who had missing data on one of the questions relating to their views on their concussion history and their current functioning. The final sample included 235 men with a mean age was 52.37 years, and half of them were between the ages of 41 and 63 years. Most were currently employed (i.e., 77.0%). Their mean number of years of participation in professional sport was 8.65 (SD = 4.68), and their mean total years of lifetime participation in the sport was 23.37 (SD = 5.66). Their mean age at retirement was 31.18 (SD = 4.54), and their mean number of years since retirement was 21.68 (SD = 14.20). Some relatively common health problems reported by the sample included arthritis (47.7%), history of depression (28.1%), headaches (26.4%), hypertension (17.0%), migraine (12.8%), and sleep apnea (13.6%). Descriptive statistics for the total sample and the sample stratified by primary playing position relating to their age, years of participation in rugby league, and lifetime history of concussion are presented in Table 1. There were significant differences between forwards and backs for the age of discontinuation from sport, with backs stopping at a younger age than forwards (p = .03) and forwards reporting greater levels of stress in the past two weeks than backs (p = .04). There were no other significant differences between playing position (see Table 1).
Descriptive statistics for demographic, sporting history, concussion history, and self-reported outcome measures in the total sample and stratified by playing position (forwards vs. backs)
| Total Sample | Forwards | Backs | p | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | M | SD | Md | 25th | 75th | n | M | SD | Md | 25th | 75th | n | M | SD | Md | 25th | 75th | ||
| Age | 235 | 52.37 | 13.40 | 53.00 | 41.00 | 63.00 | 148 | 51.67 | 13.15 | 52.00 | 41.00 | 62.75 | 87 | 53.57 | 13.81 | 55.00 | 41.00 | 65.00 | .77 |
| Education | 235 | 12.30 | 2.62 | 12.00 | 10.00 | 14.00 | 148 | 12.33 | 2.64 | 12.00 | 10.00 | 14.00 | 87 | 12.25 | 2.60 | 12.00 | 10.00 | 14.00 | .76 |
| Age Discontinuing Sport | 231 | 31.18 | 4.54 | 31.00 | 29.00 | 33.00 | 146 | 31.56 | 4.27 | 31.00 | 29.00 | 34.00 | 85 | 30.53 | 4.92 | 31.00 | 27.00 | 33.00 | .03 |
| Years Since Discontinuation | 232 | 21.68 | 14.20 | 21.50 | 9.00 | 32.00 | 146 | 20.51 | 13.73 | 20.00 | 8.00 | 30.00 | 86 | 23.67 | 14.85 | 24.50 | 10.00 | 37.00 | .42 |
| Years of Rugby League | 227 | 23.37 | 5.66 | 24.00 | 20.00 | 27.00 | 141 | 23.71 | 5.42 | 24.00 | 21.00 | 27.00 | 86 | 22.80 | 6.03 | 23.50 | 17.75 | 27.00 | .55 |
| Years at the Elite Level | 234 | 8.65 | 4.68 | 9.00 | 5.00 | 12.00 | 147 | 9.01 | 4.71 | 10.00 | 5.00 | 12.00 | 87 | 8.05 | 4.61 | 8.00 | 4.00 | 12.00 | .27 |
| Number of Lifetime Concussions | 233 | 24.75 | 39.62 | 12.00 | 6.00 | 25.00 | 146 | 25.30 | 43.49 | 12.00 | 6.00 | 25.00 | 87 | 23.83 | 32.31 | 11.00 | 5.00 | 25.00 | .46 |
| BPI Pain Severity | 221 | 2.24 | 2.29 | 2.00 | 0.00 | 4.00 | 137 | 2.13 | 2.19 | 2.00 | 0.00 | 3.63 | 84 | 2.41 | 2.46 | 2.00 | 0.00 | 4.00 | .62 |
| Life Interference Due to Pain | 225 | 1.84 | 2.23 | 0.86 | 0.00 | 3.14 | 140 | 1.83 | 2.14 | 0.86 | 0.00 | 3.50 | 85 | 1.87 | 2.39 | 0.57 | 0.00 | 3.07 | .94 |
| DASS-21 Depression | 226 | 7.10 | 8.81 | 4.00 | 0.00 | 12.00 | 144 | 7.31 | 9.20 | 4.00 | 0.00 | 12.00 | 82 | 6.73 | 8.13 | 4.00 | 2.00 | 10.00 | .95 |
| DASS-21 Anxiety | 226 | 4.63 | 5.63 | 2.00 | 0.00 | 6.00 | 144 | 4.82 | 5.78 | 2.00 | 0.00 | 7.50 | 82 | 4.29 | 5.36 | 2.00 | 0.00 | 6.00 | .33 |
| DASS-21 Stress | 227 | 10.59 | 8.96 | 10.00 | 4.00 | 16.00 | 146 | 11.11 | 8.79 | 10.00 | 4.00 | 16.00 | 81 | 9.65 | 9.25 | 8.00 | 2.00 | 14.00 | .04 |
| Resilience Total Score | 212 | 73.31 | 14.41 | 75.00 | 65.50 | 84.50 | 133 | 73.14 | 14.81 | 76.00 | 64.00 | 84.00 | 79 | 73.58 | 13.80 | 75.00 | 67.00 | 85.00 | .00 |
Note: BPI = Brief Pain Inventory, DASS = Depression, Anxiety, and Stress Scale-21, M = Mean, Md = Median, n = sample size, SD = standard deviation. The 25th and the 75th represent the lower and upper bounds of the interquartile range of values for each variable. There were missing values for some variables. Individual variable comparisons between position type were conducted using Mann–Whitney U tests, with an alpha value = 0.05. Bold text signifies p values <.05.
Spearman correlations among the self-report measures are presented in Table 2. There were moderate bivariate correlations among the measures of depression, anxiety, and stress, with correlations ranging from r = 0.58 to 0.64. Resilience was negatively correlated with measures of psychological distress (r = −0.33 to −0.50), meaning that higher scores on resilience were associated with lower scores on measures of psychological distress. There were small positive correlations between being worried about memory and thinking skills and psychological distress (r = 0.18 to 0.31).
Spearman correlations among the self-report measures
| Worried About Memory | Depression | Anxiety | Stress | Pain Severity | Pain Interference | ||
|---|---|---|---|---|---|---|---|
| Depression | Correlation | 0.223a | |||||
| p | <.001 | ||||||
| n | 226 | ||||||
| Anxiety | Correlation | 0.178a | 0.575a | ||||
| p | .007 | <.001 | |||||
| n | 226 | 223 | |||||
| Stress | Correlation | 0.306a | 0.636a | 0.634a | |||
| p | <.001 | <.001 | <.001 | ||||
| n | 227 | 224 | 225 | ||||
| Pain Severity | Correlation | 0.212a | 0.266a | 0.272a | 0.290a | ||
| p | .002 | <.001 | <.001 | <.001 | |||
| n | 221 | 213 | 214 | 214 | |||
| Pain Interference | Correlation | 0.203a | 0.290a | 0.320a | 0.345a | 0.868a | |
| p | .002 | <.001 | <.001 | <.001 | <.001 | ||
| n | 225 | 217 | 217 | 218 | 221 | ||
| Resilience | Correlation | −0.161b | −0.497a | −0.327a | −0.334a | −0.108 | −0.160b |
| p | .019 | <.001 | <.001 | <.001 | .122 | .020 | |
| n | 212 | 207 | 209 | 210 | 208 | 211 |
Note: aCorrelation is significant at the 0.01 level (2-tailed).
bCorrelation is significant at the 0.05 level (2- tailed).
n = sample size and p = p value. Worried about memory: Former players were asked verbally, in an interview: “how worried are you about the possible effects of the concussion(s) that you sustained during your career, will have on your memory and thinking skills as you get older?”
More than one in four participants, 29.8% (n = 70), reported that they were very worried about the possible effects of the concussion(s) they sustained during their career on their memory and thinking skills as they get older. The two groups, stratified based on whether they were very worried about the possible effects of past concussions on their memory and thinking skills as they get older, did not statistically differ on age at study participation, age they discontinued sport, years since discontinuing sport, or total years of participation in rugby league (Table 3). Those who were very worried about their memory and thinking skills had played more years at the elite level, with a small effect size (Table 3, g = −0.28). Those who were very worried about their memory and thinking skills reported a greater number of lifetime concussions (g = −0.30; see Table 3).
Comparing groups on participation history, concussion history, pain, mental health, and resilience
| Not Very Worried (n = 165) | Very Worried (n = 70) | p | g | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | M | SD | Md | 25th | 75th | n | M | SD | Md | 25th | 75th | |||
| Age | 165 | 53.29 | 13.77 | 54.00 | 41.00 | 64.00 | 70 | 50.21 | 12.31 | 48.00 | 40.00 | 59.00 | .129 | 0.230 |
| Education | 165 | 12.31 | 2.66 | 12.00 | 10.00 | 14.00 | 70 | 12.29 | 2.55 | 12.00 | 10.00 | 12.00 | .846 | 0.009 |
| Age Discontinuing Sport | 162 | 30.91 | 3.96 | 31.00 | 28.00 | 33.00 | 69 | 31.83 | 5.65 | 31.00 | 29.00 | 34.00 | .359 | −0.202 |
| Years Since Discontinuation | 162 | 22.74 | 14.85 | 23.00 | 10.00 | 35.00 | 70 | 19.23 | 12.33 | 19.50 | 8.00 | 28.00 | .099 | 0.248 |
| Years of Rugby League | 159 | 23.27 | 5.51 | 24.00 | 20.00 | 27.00 | 68 | 23.59 | 6.04 | 25.00 | 20.00 | 28.00 | .571 | −0.056 |
| Years at the Elite Level | 165 | 8.27 | 4.55 | 9.00 | 5.00 | 11.00 | 69 | 9.57 | 4.90 | 10.00 | 6.00 | 13.00 | .045 | −0.280 |
| Number of Lifetime Concussions | 164 | 21.24 | 30.60 | 10.00 | 5.00 | 20.00 | 69 | 33.09 | 54.86 | 15.00 | 8.00 | 30.00 | .010 | −0.300 |
| BPI Pain Severity | 155 | 2.00 | 2.16 | 1.75 | 0.00 | 3.50 | 66 | 2.80 | 2.51 | 2.63 | 0.00 | 4.50 | .029 | −0.352 |
| Life Interference Due to Pain | 157 | 1.63 | 2.11 | 0.57 | 0.00 | 2.71 | 68 | 2.34 | 2.43 | 1.57 | 0.00 | 4.14 | .024 | −0.322 |
| DASS-21 Depression | 160 | 5.44 | 7.12 | 2.00 | 0.00 | 8.00 | 66 | 11.12 | 11.03 | 8.00 | 2.00 | 16.00 | <.001 | −0.671 |
| DASS-21 Anxiety | 161 | 3.71 | 4.50 | 2.00 | 0.00 | 6.00 | 65 | 6.89 | 7.31 | 4.00 | 2.00 | 10.00 | .004 | −0.581 |
| DASS-21 Stress | 161 | 8.75 | 7.84 | 6.00 | 2.00 | 12.00 | 66 | 15.09 | 9.94 | 15.00 | 8.00 | 20.00 | <.001 | −0.744 |
| Resilience Total Score | 148 | 74.81 | 14.16 | 77.00 | 67.00 | 85.50 | 64 | 69.83 | 14.49 | 73.50 | 60.50 | 79.00 | .024 | 0.348 |
Note: Groups were compared using Mann–Whitney U tests. BPI = Brief Pain Inventory, DASS = Depression, Anxiety, and Stress Scale-21, g = Hedges’ g effect size, M = Mean, Md = Median, SD = standard deviation. The 25th and the 75th represent the lower and upper bounds of the interquartile range of values for each variable. Former players were asked verbally, in an interview: “how worried are you about the possible effects of the concussion(s) that you sustained during your career, will have on your memory and thinking skills as you get older?” Binary groups were formed, with those who rated themselves as 6 or 7 classified as “very worried” and all others classified as “not very worried.” Bold text signifies p values <.05.
The two groups were compared on their pain ratings, mental health, and resilience. As seen in Table 3, they significantly differed on pain severity (g = −0.35) and pain interference (g = −0.32), with those who were very worried reporting greater chronic pain (with small effect sizes). Those who were very worried about their concussion history and their future functioning reported greater symptoms of depression (g = −0.67), anxiety (g = −0.58), and life stress (g = −0.74), with effect sizes that were medium to approaching large for life stress. There were 29.2% (n = 66/226) of the sample who reported moderate–severe depression, anxiety, or stress on the DASS-21. Those who were very worried about their concussion history affecting their memory and thinking skills were more likely to report moderate–severe current psychological distress (47.8%, n = 32/67) compared to those who were not worried (21.4%, n = 34/159; χ2 (1) = 15.86, p < .001, OR = 3.36, 95% CI = 1.82–6.19).
A multivariable binary logistic regression predicting moderate–severe psychological distress was significant [χ2 (7) = 58.37, p < .001; Nagelkerke R2 = 0.37] and revealed that greater number of lifetime concussions (OR = 1.01, 95% CI = 1.00–1.03), lifetime history of depression (OR = 3.20, 95% CI = 1.44–7.14), lower resilience (OR = 0.96, 95% CI = 0.93–0.99), and being very worried about their concussion history (OR = 3.29, 95% CI = 1.49–7.23) were independently associated with current moderate–severe psychological distress (see Table 4, sample size = 196). Total years of participation in rugby league, years of participation at the professional level, and life interference due to chronic pain were not independently associated with psychological distress.
Predicting moderate–severe psychological distress
| Adjusted OR with 95% CI | Unadjusted OR with 95% CI | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| B | SE | Wald | p | OR | Lower | Upper | OR | Lower | Upper | |
| Years of Participation | 0.00 | 0.03 | 0.01 | .910 | 1.00 | 0.94 | 1.07 | 1.01 | 0.95 | 1.06 |
| Years of Participation at the Elite Level | −0.09 | 0.040 | 3.71 | .054 | 0.92 | 0.84 | 1.00 | 0.96 | 0.90 | 1.02 |
| Number of Lifetime Concussions | 0.01 | 0.010 | 5.74 | .017 | 1.01 | 1.00 | 1.03 | 1.02 | 1.00 | 1.03 |
| Life Interference Due to Pain (Binary) | 0.40 | 0.43 | 0.88 | .348 | 1.49 | 0.65 | 3.44 | 2.42 | 1.22 | 4.79 |
| History of Depression | 1.16 | 0.41 | 8.09 | .004 | 3.20 | 1.44 | 7.14 | 5.07 | 2.58 | 9.97 |
| Resilience Total Score | −0.04 | 0.01 | 8.90 | .003 | 0.96 | 0.93 | 0.99 | 0.94 | 0.92 | 0.97 |
| Very Worried About Concussion History | 1.19 | 0.40 | 8.75 | .003 | 3.29 | 1.49 | 7.23 | 3.51 | 1.82 | 6.77 |
| Constant | 1.38 | 1.35 | 1.06 | .304 | 3.99 | — | — | — | ||
Note: These analyses (adjusted and unadjusted) are based on 196 subjects with complete data on all variables. The unadjusted ORs are derived from a series of univariable binary logistic regression analyses. The adjusted ORs are derived from a single multivariable logistic regression analysis. B = beta, CI = confidence interval, OR = odds ratio, and SE = standard error. Bold text signifies p values <.05.
DISCUSSION
Some former elite and professional rugby league players report considerable worry about the possible effects of concussions they experienced during their playing years on their memory and thinking skills as they get older. For the subgroup who reported that they were very worried about the possible effects of concussions on their cognitive functioning, they reported experiencing much greater current symptoms of depression, anxiety, and stress than those former players who were not worried about their memory and thinking skills (see Table 3). They also reported modestly greater life interference due to pain. Those with a high degree of worry were two to three times more likely to report moderate to severe levels of depression, anxiety, or stress. These results align, to some degree, with results from studies with former professional American-style football players. Prior studies with former NFL players indicate that some of them are very concerned about their memory, thinking skills, and developing CTE, and these concerns are associated with psychological distress (Walton et al., 2022). Former NFL players who think they have CTE experience greater psychological distress and are much more likely to report suicidality than those who do not think they have CTE (Grashow et al., 2024).
The results from this sample of former players are compared to samples from the literature in Table 5. For those former players who were not very worried about their memory and thinking skills, their scores on depression, anxiety, and stress were similar to the general population (Crawford et al., 2009; Crawford et al., 2011; Lovibond & Lovibond, 1996; Sinclair et al., 2012), lower than outpatients with mental health problems (Ronk et al., 2013), and much lower than people in treatment for chronic pain conditions (Nicholas et al., 2019). For those former players who were very worried about their memory and thinking skills, their scores on depression, anxiety, and stress were modestly greater than the general population (Crawford et al., 2009; Crawford et al., 2011; Lovibond & Lovibond, 1996; Sinclair et al., 2012), modestly lower than outpatients with mental health problems (Ronk et al., 2013), and much lower than people in treatment for chronic pain conditions (Nicholas et al., 2019) (see Table 5).
Comparing the current sample to selected studies using the DASS-21 in subjects from the general population and from those with chronic pain or mental health problems
| Age | Test Score | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Measure/Group | First Author | Publication Year | Country | N | M | SD | % Men | M | SD |
| DASS-21 Depression | |||||||||
| General Population | Sinclair | 2012 | USA | 499 | 44.7 | 16.3 | 48 | 5.70 | 8.20 |
| General Population | Crawford | 2009 | UK | 2,928 | 40.85 | 15.98 | 56.76 | 3.18 | 5.39 |
| General Population | Crawford | 2011 | Australia | 497 | 42.14 | 17.93 | 55.53 | 2.57 | 3.86 |
| General Population | Lovibond | 1996 | Australia | 2,914 | — | — | 35.8 | 6.34 | 6.97 |
| Chronic Pain Patients | Nicholas | 2019 | Australia | 13,250 | 52.7 | 15.76 | 41.6 | 20.2 | 12.8 |
| Outpatient Mental Health | Ronk | 2013 | USA | 1,000 | 42.9 | 16.2 | 36.8 | 13.32 | 11.10 |
| Inpatient Psychiatry | Ronk | 2013 | Australia | 3,964 | 41.5 | 15.3 | 26.5 | 32.15 | 11.41 |
| Former Rugby League Players | |||||||||
| Total Sample (n = 226) | Present Study | 2025 | Australia | 235 | 52.37 | 13.40 | 100 | 7.10 | 8.81 |
| No Major Worry (n = 160) | Present Study | 2025 | Australia | 165 | 53.29 | 13.77 | 100 | 5.44 | 7.12 |
| Very Worried (n = 66) | Present Study | 2025 | Australia | 70 | 50.21 | 12.31 | 100 | 11.12 | 11.03 |
| DASS-21 Anxiety | |||||||||
| General Population | Sinclair | 2012 | USA | 499 | 44.7 | 16.3 | 48 | 3.99 | 6.27 |
| General Population | Crawford | 2009 | UK | 2,928 | 40.85 | 15.98 | 56.76 | 2.25 | 3.34 |
| General Population | Crawford | 2011 | Australia | 497 | 42.14 | 17.93 | 55.53 | 1.74 | 2.78 |
| General Population | Lovibond | 1996 | Australia | 2,914 | — | — | 35.8 | 4.70 | 4.91 |
| Chronic Pain Patients | Nicholas | 2019 | Australia | 13,250 | 52.7 | 15.76 | 41.6 | 14.1 | 10.9 |
| Outpatient Mental Health | Ronk | 2013 | USA | 1,000 | 42.9 | 16.2 | 36.8 | 9.09 | 8.82 |
| Inpatient Psychiatry | Ronk | 2013 | Australia | 3,964 | 41.5 | 15.3 | 26.5 | 23.45 | 11.76 |
| Former Rugby League Players | |||||||||
| Total Sample (n = 226) | Present Study | 2025 | Australia | 235 | 52.37 | 13.40 | 100 | 4.63 | 5.63 |
| No Major Worry (n = 161) | Present Study | 2025 | Australia | 165 | 53.29 | 13.77 | 100 | 3.71 | 4.50 |
| Very Worried (n = 65) | Present Study | 2025 | Australia | 70 | 50.21 | 12.31 | 100 | 6.89 | 7.31 |
| DASS-21 Stress | |||||||||
| General Population | Sinclair | 2012 | USA | 499 | 44.7 | 16.3 | 48 | 8.12 | 7.62 |
| General Population | Crawford | 2009 | UK | 2,928 | 40.85 | 15.98 | 56.76 | 5.16 | 4.44 |
| General Population | Crawford | 2011 | Australia | 497 | 42.14 | 17.93 | 55.53 | 3.99 | 4.24 |
| General Population | Lovibond | 1996 | Australia | 2,914 | — | — | 35.8 | 10.11 | 7.91 |
| Chronic Pain Patients | Nicholas | 2019 | Australia | 13,250 | 52.7 | 15.76 | 41.6 | 21 | 11.5 |
| Outpatient Mental Health | Ronk | 2013 | USA | 1,000 | 42.9 | 16.2 | 36.8 | 15.01 | 10.00 |
| Inpatient Psychiatry | Ronk | 2013 | Australia | 3,964 | 41.5 | 15.3 | 26.5 | 30.40 | 10.44 |
| Former Rugby League Players | |||||||||
| Total Sample (n = 227) | Present Study | 2025 | Australia | 235 | 52.37 | 13.40 | 100 | 10.59 | 8.96 |
| No Major Worry (n = 161) | Present Study | 2025 | Australia | 165 | 53.29 | 13.77 | 100 | 8.75 | 7.84 |
| Very Worried (n = 66) | Present Study | 2025 | Australia | 70 | 50.21 | 12.31 | 100 | 15.09 | 9.94 |
Note: M = mean, SD = standard deviation, % = percentage, USA = United States of America, UK = United Kingdom. For the Sinclair et al. (2012) study the total sample was 503 but 499 had complete data presented on the measure. All of the data from past normative and clinical samples presented in this table were derived from previously published studies (Crawford et al., 2009; Crawford et al., 2011; Nicholas et al., 2019; Ronk et al., 2013; Sinclair et al., 2012), with the exception of the normative data from (Lovibond & Lovibond, 1996), which were presented in the article by Ronk and colleagues but listed as 1995, not 1996 (Ronk et al., 2013). Data from Nicholas and colleagues were from patients attending pain clinics in Australia and New Zealand (Nicholas et al., 2019). Decimal places differ in this table because some studies reported zero, one, or two decimal places.
In this study, there was a small association between worrying about the possible long-term effects of concussions and self-reporting a greater number of lifetime concussions (Table 3; g = −0.30). In the multivariable analysis, after adjusting for other variables, this association remained significant (Table 4). We have no way of determining the accuracy of each former player’s estimated lifetime concussion history. Given that we used a fairly broad definition, and we did not require the injuries to be medically diagnosed or to meet specific diagnostic criteria for mild traumatic brain injury (Silverberg et al., 2023), it seems likely that the former players could have interpreted and applied this definition differently. There is no way of knowing the extent to which greater concussion history contributes to greater worry, greater worry contributes to greater perceived lifetime concussion history, or both. Stated differently, it is possible that having greater worry about the possible long-term effects of concussions has a biasing effect for some people—and contributes to being more focused on one’s injury history and remembering it as greater than it was. In one prior study, there was an association between psychological distress and remembering and reporting a greater history of concussions (Kerr et al., 2012).
Clinical Implications
The results of this study have implications for the psychological health and quality of life of former collision sport athletes. Those with the greatest amount of worry about how their prior concussions may affect their cognitive functioning reported considerably more psychological distress, in terms of symptoms of depression, anxiety, and stress. It is not possible to determine the direction of this association, and it is reasonable to assume that the association is bidirectional. For some people, greater psychological distress in general likely contributes to greater worry about the possible effects of past concussions on current and future cognitive functioning. For other people, greater worry about the possible effects of past concussions on cognitive functioning likely contributes to greater psychological distress. And for some people, both might be operative. Providing a multimodal approach to treatment, including psychological interventions, prescribed and monitored exercise, and medications (if indicated) might lead to considerable improvement in psychological health and quality of life. If indicated, psychological treatment might also address ruminative worry about brain health and promote hope and optimism for improvement. Some former players might have some fatalistic misconceptions about the state of the science regarding what is known and not known about the brain health of former contact sport athletes. If so, some gentle education about what is known (Iverson et al., 2023; Patricios et al., 2023) could be used to address these misconceptions and to reduce the psychological distress associated with them.
Limitations
This study has important limitations. First, the outcome variables of interest were self-reported, and thus they could be influenced by personality factors or reporting biases. Second, concussion history was self-reported, and the accuracy of this variable, as discussed above, could not be verified. Third, we assessed worry about the effects of past concussions on cognitive functioning with a single question, and thus our evaluation of this psychological construct is limited. Fourth, we did not consider the potential effect of participants’ history of learning disorder and/or attention deficit hyperactivity disorder on their subjective view of their cognitive functioning. Finally, the direct generalizability of our results to the population of former elite and professional rugby league players, and former amateur, elite, and professional athletes from other contact and collision sports, is unknown.
CONCLUSION
Worry and rumination are considered maladaptive emotion regulation behaviors that are associated with, and magnify, difficulties with anxiety, depression, and sleep. More than one in four former elite rugby league players (29.2%) reported that they were very worried about the possible effects of their concussion history on their memory and thinking skills as they get older. Those who were very worried about their concussion history were much more likely to report moderate–severe current psychological distress. The association is likely bidirectional, and the direction of the association, for any given person, might influence some aspects of the approach to psychological treatment. Providing a multimodal approach to treatment, including psychological interventions, prescribed exercise, and medications, if indicated, might lead to considerable improvement in the psychological health and quality of life of these former elite and professional athletes.
FUNDING
The research program from which this study was conducted has been supported by the NSW Sporting Injuries Committee, the Brain Foundation, Australia, NHMRC Investigator Grant, and unrestricted philanthropic from the National Rugby League. The authors also acknowledge the Tooth Foundation and the Hunter Medical Research Institute.
CONFLICT OF INTEREST
GLI serves as a scientific advisor for NanoDX®, Sway Operations, LLC, and Highmark, Inc. He has a clinical and consulting practice in forensic neuropsychology, including expert testimony, involving individuals who have sustained mild TBIs. He has received past research support or funding from several test publishing companies, including ImPACT Applications, Inc., CNS Vital Signs, and Psychological Assessment Resources (PAR, Inc.). He has received research funding as a principal investigator from the National Football League, and subcontract grant funding as a collaborator from the Harvard Integrated Program to Protect and Improve the Health of National Football League Players Association Members. OJS has nothing to declare. DPT serves as a scientific advisor for HitIQ. He previously consulted for REACT Neuro, Inc. He has a consulting practice in forensic neuropsychology, including expert testimony, involving individuals who have sustained mild TBIs (including former athletes). He received research funding from Amgen, Inc. and Football Research Inc. AJG has a clinical practice in neuropsychology involving individuals who have sustained sport-related concussion. He is a concussion consultant to Rugby Australia and the Sydney Swans Football Club. He is the global clinical lead for the World Rugby Brain Health Service. He is a member of the World Rugby Concussion Working Group, and a member of the Australian Football League Concussion Scientific Advisory Committee. He has received travel funding or been reimbursed by professional sporting bodies, and commercial organisations for discussing or presenting sport-related concussion research at meetings, scientific conferences, workshops, and symposiums. He is supported by a National Health and Medical Research Council (NHMRC) Investigator Grant. He acknowledges unrestricted philanthropic support from the National Rugby League, the International Olympic Committee, the Australian Sports Commission, and World Rugby for research in former elite level athletes.
ACKNOWLEDGMENTS
A portion of the data from this study were presented at the at the annual conference of the International Neuropsychological Society, February 14, 2025, New Orleans, Louisiana.
AUTHOR CONTRIBUTIONS
Grant L. Iverson (Conceptualization, Formal analysis, Methodology, Writing—original draft, Writing—review & editing), Douglas P. Terry (Conceptualization, Formal analysis, Validation, Writing—review & editing), Oliver J. Smith (Formal analysis, Project administration, Validation, Writing—review & editing), and Andrew J. Gardner (Conceptualization, Data curation, Funding acquisition, Investigation, Methodology, Project administration, Resources, Writing—review & editing)
