CHRONIC DAILY HEADACHE
Abstract:Colás R, Munoz R, Temprano R, Gómez C, Pascual J. Chronic daily headache with analgesic overuse: Epidemiology and impact on quality of life. Neurology. 2004;62:1338-1342.
Objective: To analyze the prevalence and demography of chronic daily headache (CDH) with analgesic overuse.
Methods: A population of 9984 inhabitants aged 14 or older living in Santoña, Spain, was studied. The authors personally interviewed 4855 subjects, using a quota sampling approach. Those with headache for 10 days/month and some analgesic use were asked to fill in a diary over the course of 1 month. Then, subjects were classified into CDH with or without analgesic overuse subtypes. Quality of life (Short Form-36 Health Survey [SF-36]) was also assessed in this second interview.
Results: Headache for 10 days/month with analgesic consumption was reported by 332 subjects. Seven had secondary headache. Seventy-four (standardized prevalence 1.41%, 95% CI 1.1 to 1.8) fulfilled the criteria for CDH with analgesic overuse. Prevalence in women (2.6%, 2.0 to 3.3) was much higher than in men (0.19%, 0.006 to 0.52). Mean age was 56 years (range 19 to 82 years). As recalled by the subjects, the mean age at onset of CDH was 38 years (range 9 to 82 years), whereas the mean age at onset of CDH with frequent analgesic consumption was 45 years (range 19 to 80 years) and that of primary headache was 22 years (range 5 to 60 years). CDH subjects showed a significant decrease in each SF-36 health-related score as compared with healthy control subjects. Transformed migraine was diagnosed in 49 (prevalence 0.9%), chronic tension-type headache in 20 (0.4%), and new daily persistent headache in 5 (0.1%). Thirty-five percent of patients overused simple analgesics, 22% ergotics, 12.5% opioids, and 2.7% triptans; the remaining 27.8% were overusing different combinations.
Conclusion: CDH with analgesic overuse is a common disorder in the general population, mainly in women in their fifties, in whom 5% meet its diagnostic criteria.
Comment: This paper is important and also worrying. Spain and other Latin countries have historically allowed access to prescription only medicines, via pharmacies, without a physician's authorization (I write this partly based on my own anecdotal experience of purchasing them without authorization). This probably explains the high proportion of ergot-related-analgesic abuse and may suggest the same fate for the triptans when they become more widely available. It would be helpful for the IHS and AHS to provide a framework to ensure responsible access to these important prescription-only pharmaceuticals. —David S. Millson
Document Type: Research Article
Publication date: October 1, 2004