Diagnostic value of the criteria of the International Headache Society in the differential diagnosis of primary headaches

Introduction. In this research we study primary headaches, which are currently considered to be a public health problem. We also examine the fact that an ever-increasing number of people are affected and that in some cases such headaches can eventually be disabling because they bring about different degrees of functional deterioration, which leads to negative repercussions on occupational capacity and on the quality of life of the people who suffer them. Aims. Our aim is to determine the diagnostic value of the criteria of the International Headache Society (IHS) in the differential diagnosis of tension-type headaches (TH) and migraine (M) in patients who attend the Neurology outpatients department at the Dr. Luis Guada Lacau clinic. Patients and methods. 100 consecutive patients, over the period between March and August 2001, were studied and, through an interview, we applied the IHS criteria to determine the type of primary headache they suffered from; blind comparisons of results were conducted against the diagnosis provided by an expert. Results. Findings reveal a high degree of sensitivity (84, 85, 92 and 89%) for migraine with aura (MA), migraine without aura (MWA), TH, M + TH, respectively, and a specificity of 92, 95, 95 and 96% for MA, MWA, TH, M + TH, respectively, which correlates with the values obtained for the positive and negative predictive values, and the positive and negative probability coefficient. Conclusions. The IHS criteria are of great value in establishing HT, MA or MWA diagnoses and in those in which TH and M are presented together, and can therefore be used without risk in medical practice, if they are applied correctly. We recommend the use of these criteria in the General medicine and the Neurology clinic to detect cases of primary headaches and classify them correctly, thus enabling a correct diagnosis and effective therapy to be established.