Headaches, a common nuisance, have been one of the biggest reasons for medical evacuation of military personnel from Iraq and Afghanistan, according to research conducted by Steven P. Cohen, an associate professor of anesthesiology and critical care medicine at the Hopkins School of Medicine.
Cohen's research team reviewed records of 985 military personnel who returned to the US due to headaches between 2004 and 2009. The records did not include those who suffered from head trauma. Of these soldiers, 67 percent of them were not redeployed.
One may wonder — how can I prevent headaches? What causes headaches in the first place? Headaches typically seem to be induced out of the blue, without direct causation by physical trauma.
Our brains do not have nociceptors, or pain receptors. However, physiological structures around the brain are pain-sensitive, including extracranial arteries, large veins, cranial and spinal nerves and the meninges. Once the pain receptors are stimulated by traction or irritation, they send signals to our brain messaging us that we are in pain — this stimulation is the cause of our headaches.
Unfortunately, research cannot quantify the pain levels of these headaches and can only rely on the victim's assessment of the pain. Thus, the research led by Cohen aimed to evaluate the impact of headaches on military personnel, as well as identify factors of these headaches.
Stress is a well-known factor for headaches. The parasympathetic nervous system, a branch of the autonomic nervous system, responds to stress by dilating blood vessels, which can in turn stimulate the nociceptors surrounding it. Serving in the military amplifies many stressors, making soldiers particularly vulnerable to headaches.
Cohen also attributed the pains to the Kevlar helmets, required to be worn by every soldier. The helmets weigh 3.1 to 4.2 lbs. The weight pressures the occipital nerve, a spinal nerve located in the back of your head near the top of the neck, inducing stimulations to nociceptors there.