Athletes at Risk?

A 60-year-old man pruning a pear tree slips and falls, hits his head hard on the ground and goes to the hospital with mild concussion and a herniated disk in his neck. Two vertebrae are fused, he returns home, and except for a decrease in his range of motion, the man seems to have survived the incident intact. But did he?

By his late 70s, the man's memory lapses are a concern. When he dies, at age 84, an autopsy reveals characteristic tangles in his brain that confirm he'd developed Alzheimer's.

To what extent do bad bumps to the head hasten the onset of the "long goodbye?"

According to the Mayo Clinic (www.mayoclinic.com), a study involving former boxers has found a link between concussion to the brain and dementias like Alzheimer's disease. A recently released study of athletes who suffer concussions points, too, to the heightened risk.

Those who engage in active sports such as:

• Boxing
• Football
• Rollerblading
• Hockey
• Cycling (bicycles and motorized)
• Baseball

are advised to don protective headgear, to lessen the impact to the brain should they sustain a blow to the head.

A concussion of the brain, as defined by http://www.medterms.com/, is "a traumatic injury to the brain as a result of a violent blow, shaking, or spinning. A brain concussion can cause immediate and usually temporary impairment of brain function," such as of thinking, vision, equilibrium and consciousness. In athletes, according to the American Medical Association (http://www.ama.com/), symptoms of concussion may include:

• Player appears dazed
• Player has vacant facial expression
• Confusion about assignment
• Athlete forgets plays
• Disorientation to game or score
• Inappropriate emotional reaction
• Player displays clumsiness
• Player is slow to answer questions
• Loss of consciousness
• Any change in typical behavior
• Headache
• Nausea
• Dizziness or balance problems
• Double or fuzzy vision
• Sensitivity to light or noise
• Feeling slowed down
• Feeling "foggy" or "not sharp"
• Sleep pattern changes
• Concentration or memory problems
• Irritability
• Sadness
• Feeling more emotional

The American Academy of Neurology (http://www.aan.com/) guidelines for when athletes with concussion can resume play divide concussions into three grades of severity. A prolonged knockout is the worst. Athletes whose headaches, nausea, amnesia and blurred vision do not clear up within 15 minutes, or who lose consciousness even briefly, should, the Academy says, be kept out of competition until their symptoms have disappeared completely for at least a week.

A person who has had a concussion is as much as four times more likely to get a second one. After several concussions, a lesser blow can cause one, and it takes more time to recover.

Here are concussion facts according to medterms.com:

Impact: The concussion occurs from impact when the head accelerates rapidly and then is stopped, or from spinning when the head is spun rapidly and then is stopped. Impact to the brain can occur when the head slams into a hard surface. The skull is stopped by the hard surface but the brain, floating in cerebrospinal fluid (CSF), can still move and is shaken.

Spinning: Spinning of the brain can occur when a blow causes the head to snap rapidly. The skull then stops spinning but the brain, floating in cerebrospinal fluid (CSF), can still move and is damaged.

Violent trauma: Violent trauma, whether it be from shaking or spinning, causes the brain cells to become depolarized and fire all their neurotransmitters at once in an abrupt cascade, flooding the brain with chemicals - there is a sudden flood of ions (including sodium, potassium, and calcium) - and deadening receptors in the brain that are associated with learning and memory.

Second impact syndrome: Sometimes a person has a second concussion before their brain has recovered from the first. This can lead to what is called second impact syndrome. In the second impact syndrome, massive swelling of the brain causes pressure inside the skull that chokes off the flow of fresh blood and leads to irreparable brain damage or death.

Recovery from concussion: It takes considerable time and energy for the brain to correct this chemical imbalance. Changes in the brain start to resolve immediately, but the recovery time seems to vary. The time depends not only on the severity of the blow, but also on how many previous concussions a person has had.

After a concussion: The arteries in the brain constrict. This reduces blood flow to the brain and lowers the rate at which oxygen is delivered to the brain. At the same time the demand rises for the sugar glucose which provides energy to the brain for healing. But the need for more glucose cannot be met by the narrowed arteries and this discrepancy ("mismatch") creates a metabolic crisis. Eventually the damaged brain cells (that survive) do slowly repair themselves, the demand for glucose eases, the arteries to the brain open wider, and blood flow to the brain returns to normal. However, the brain stays in a lowered metabolic state, a quiescent condition, for a considerable length of time before it can return to normal.

Symptoms of concussion, says www.health-care-clinic.org, may also include ringing in the ears. According to this site, differentiating between concussion and more serious head injuries requires a thorough history of the trauma and a neurological examination. Such an examination must evaluate the patient's level of consciousness (LOC), mental status, cranial nerve and motor function, deep tendon reflexes, and orientation to time, place, and person.

If no abnormalities are found and if severe head injury appears unlikely, the patient should be observed for signs of more severe cerebral trauma. Observation provides a baseline for gauging any deterioration in the patient's condition.

Computed tomography (CT) scans may rule out fractures and more serious injuries. To avoid falls that could result in concussion, older people are advised to choose sensible footwear, such as thinner, hard-soled, flat shoes. Resilient-soled athletic shoes may impair balance and contribute to falls. Avoid, too, high heels, sandals with light straps, or shoes that are either too slippery or too sticky.

According to recent research, as many as 3.8 million athletes a year may suffer bumps to the brain that could one day dramatically increase their risk of Alzheimer's or crippling depression.

Conservative estimates say a full blown concussion is experienced annually by 350,000 U.S. athletes - athletes who are conditioned to ignore pain and keep on playing. Three concussions over a lifetime, some researchers say, and a person is at five times the risk for early onset Alzheimer's, and four times more likely to develop severely elevated depression (http://www.nih.gov/).

The Mayo Clinic defines Alzheimer's as a complex disease likely caused by a combination of factors - such as infection or reduced circulation - and genetic susceptibility. Although all the contributing factors may never be known, scientists have identified several common threads, which may include head injury. The Clinic states: "The observation that some ex-boxers eventually develop dementia suggests that serious traumatic injury to the head (for example, a concussion with a prolonged loss of consciousness) may be a risk factor for Alzheimer's. Several studies indicate a definite link between the two, but others show no link."

Because it's not yet known how such head injuries may manifest themselves in today's athletes 15 to 20 years from now, there's a move afoot to improve helmets and chin guards to protect heads better.