Diagnosis, epidemiology, and impact of tension-type headache.

Although tension-type headache is the most prevalent headache and affects 78% of the general population, the substantial societal and individual burden associated with this primary headache has been overlooked. In contrast to migraine headache, there has been limited focus on tension-type headache. Most patients with the chronic form of tension-type headache, which affects 3% of the population, are left virtually without any specific treatment. Chronic tension-type headache differs from the episodic form in frequency, lack of effect to most treatment strategies, more medication overuse, and more loss of quality of life. Daily or near daily headaches also constitute a major diagnostic and therapeutic problem and distinguishing chronic tension-type headache from migraine headache and from medication-induced headache is a substantial diagnostic challenge because management strategies are completely different. Considerable benefits for the society can be gained by specific strategies leading to reductions in the amount of sickness absence and impaired working abilities. The burden on the affected patients' and their families' quality of life also may be improved by a general acceptance of the disorder and by the development of a specific treatment strategy.