Tension-type headache and migraine: two points on a continuum?

The question of whether tension-type headache (TTH) and migraine represent two points on a continuum has been debated for decades. Skeptics of the continuum model support their view by noting that the characteristics of these two headaches and the demographics of the individuals who suffer from them are undeniably distinct. In the clinical setting, however, these disorders exhibit more similarities than differences. TTH and migraine may exhibit similar associated features (even within the constraints of diagnostic criteria), respond effectively to similar medications, share similar demographics among certain age groups, and may each have genetic influences. These findings suggest that TTH and migraine may be more intimately related than would be suggested by their diagnostic criteria.