The notion that hypertension causes headache is widely accepted despite the absence of confirmation by well-designed studies.
To investigate the association between headache, characterized as tension type and migraine like, with blood pressure and hypertension.
In a cross-sectional study we evaluate this association in a sample of 1174 individuals older than 17 years, representative of inhabitants of Porto Alegre, RS, Brazil. Headache and its subtypes were defined according to International Headache Society criteria. Hypertension was defined as the mean of two blood pressure readings ≥140/90 mmHg or use of antihypertensive drugs.
Headache in lifetime, in the last year, and defined as episodic and chronic tension-type headache was not associated with hypertension. Individuals with optimal or normal blood pressure (Sixth Joint National Committee criteria) complained of migraine more frequently than the participants with high-normal blood pressure or hypertension. This association persisted after adjustment for several potential confounding factors (risk ratio, 0.56; confidence interval, 0.41–0.77).
Our findings confirm that high blood pressure is not associated with the complaint of headache in the population. Individuals with migraine-like episodes of headache may have lower blood pressure than individuals without headache.
aDivision of Cardiology, Hospital de Clínicas de Porto Alegre; bDepartment of Social Medicine, School of Medicine and cDepartment of Pharmacology, Health Sciences Institute, Universidade Federal do Rio Grande do Sul, Brazil.
Sponsorship: Supported by grants from Conselho Nacional de Pesquisas (CNPq) and Fundação de Amparo à Pesquisa do Rio Grande do Sul (FAPERGS).
Correspondence and requests for reprints to Flávio Danni Fuchs MD, PhD, Serviço de Cardiologia, Hospital de Clínicas de Porto Alegre, Ramiro Barcelos, 2350 90.035-003, Porto Alegre, RS, Brazil. Tel./fax: +55 51 3316 8420; e-mail: email@example.com
Received 19 September 2001
Revised 8 March 2002
Accepted 20 March 2002