If 100 US adults are followed over their entire lifetime, 16 will have at least one episode of clinical depression (the lifetime prevalence of depression is 16.5 percent).

In any given single year, 6 of the 100 will experience depression symptoms that meet the diagnostic clinical depression criteria. The 12-month prevalence of depression is actually higher in the 18-25 age group compared to the 26-49 or 50+ age groups (8 percent compared to 7 percent or 5 percent). So what do these facts have to do with athletes and sports medicine?

It is a common perception that athletes, by virtue of their athletic endeavors, are somehow immune to depression and other mood disorders. Though there is not enough research yet to definitively refute this belief, it is very likely that this is not true. In other words, it is a myth that athletes are immune to depression, anxiety, and other mood disorders simply because they participate in competitive athletics. We also know that an athlete may have different risk factors for developing depression, such as having an injury or having an athletic career come to end, when compared to non-athletes.

Most of the research so far of how widespread an issue this is has been done in college athletes, with a few studies in retired professional athletes and even less in adolescent athletes. Yang, published in the Clinical Journal of Sports Medicine in 2007, surveyed 250 NCAA D1 athletes at one university, including football players, and revealed that 21 percent reported symptoms of depression.

Injuries were associated with a higher risk of reporting depressive symptoms. A survey of retired NFL players by Schwenk reported 14.5 percent of the 1500 respondents scoring in the moderate to severe category of a validated depression screening questionnaire. Perhaps it is no surprise to learn in the same study that the higher (worse) the depression score, the more likely the retired player reported financial difficulties, lack of social supports, alcohol and substance use, and "trouble to transition to life after football."

The stigma of having a mental health illness is perhaps less than it has been previously in the general population. In the culture of sports, where "mental toughness" is as valued as physical prowess, however, we still have room to improve in terms of our acceptance and understanding of depression and mood disorders in athletes.

On the one hand, we have Ron Artest, aka Metta World Peace, who after winning the NBA finals in 2010 publically thanked his psychiatrist in his post-game 7 interview. Unfortunately, the tragedy of Junior Seau who ended his own life reminds us that even a NFL Hall of Fame caliber athlete is not immune to mental health concerns.

A survey of over 800 sports medicine physicians regarding psychological issues in athletes concluded that 80 percent of sports docs discuss psychological issues related to injury with athletes, and that there is a need for improved care of athletes with psychological issues. In order to optimize our care of depression in athletes, we as health care providers need to better understand the challenges of depression in athletes. It is very likely that, for a variety of reasons, mental health symptoms and disorders are underreported, underdiagnosed, and undertreated in the athletic population.

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