Birthe Krogh Rasmussen

Epidemiology of headache in a general population—A prevalence study

We present the first prevalence study of specific headache entities using the operational diagnostic criteria of the International Headache Society. One thousand 25-64 year old men and women, who lived in the western part of Copenhagen County were randomly drawn from the Danish National Central Person Registry. All subjects were invited to a general health examination focusing on headache and including: a self-administered questionnaire concerning sociodemographic variables, a structured headache interview and a general physical and neurological examination. The participation rate was 76%. Information about 79% of the non-participants showed a slightly differing headache prevalence which was not quantitatively important. The following results in participants are therefore representative of the total sample. The lifetime prevalences of headache (including anybody with any form of headache), migraine, and tension-type headache were 93, 8 and 69% in men; and 99, 25 and 88% in women. The point prevalence of headache was 11% in men and 22% in women. Prevalence of migraine in the previous year was 6% in men and 15% in women and the corresponding prevalences of tension-type headache were 63 and 86%. Differences according to sex were significant with a male: female ratio of 1:3 in migraine, and 4:5 in tension-type headache. The prevalence of tension-type headache decreased with increasing age, whereas migraine showed no correlation to age within the studied age interval. Headache disorders are extremely prevalent and represent a major health problem, which merits increased attention.

Migraine with aura and migraine without aura: an epidemiological study

In a cross-sectional study of headache disorders in a representative general population of 1,000 persons the epidemiology of migraine with aura (MA) and migraine without aura (MO) was analysed in relation to sex and age distribution, symptomatology and precipitants. The headache disorders were classified on the basis of a clinical interview as well as a physical and a neurological examination using the operational diagnostic criteria of the International Headache Society (IHS). Lifetime prevalence of MA was 5%, male:female ratio 1:2. Lifetime prevalence of MO was 8%, M:F ratio 1:7. Women, but not men, were significantly more likely to have MO than MA. Neither MA nor MO showed correlation to age in the studied age interval (25–64 years). Premonitory symptoms occurred in 16% of subjects with MA and in 12% with MO. One or more precipitating factor was present in 61% with MA and in 90% with MO. In both MA and MO the most conspicuous precipitating factor was stress and mental tension. Visual disturbances were the most common aura phenomenon occurring in 90% of subjects with MA. Aura symptoms of sensory, motor or speech disturbances rarely occurred without coexisting visual disturbances. The pain phase of MA fulfilled the criteria for MO of the IHS. Headache was, however, less severe and shorter lasting in MA than in MO. Onset at menarche, menstrual precipitation, menstrual problems, influence of pregnancy and use of oral contraceptives all showed some relationship with the presence of MO and less with MA. The present findings suggest that MA and MO share the pain phase. Among subjects with MA and MO, 50% and 62%, respectively, had consulted their general practitioner because of migraine. Selection bias in previous clinical studies is demonstrated by comparisons with the present unselected sample.

Migraine and tension-type headache in a general population: precipitating factors, female hormones, sleep pattern and relation to lifestyle

&NA; In a cross‐sectional epidemiological study of headache disorders information on precipitating factors, age at onset, influence of menstruation and pregnancy and use of oral contraceptives was collected. The presence of migraine and tension‐type headache was ascertained by a clinical interview and examination using the operational diagnostic criteria of the International Headache Society. The prevalence of migraine and tension‐type headache was also analysed in relation to variables of lifestyle: physical activity, smoking, consumption of coffee, alcohol intake and sleep pattern. In both migraine and tension‐type headache, the most conspicuous precipitating factor was stress and mental tension. Other common precipitants were alcohol, weather changes and menstruation. Disappearance or substantial improvement of the headache during pregnancy was more frequent in migraineurs than in tension‐type headache sufferers. The age at onset of both migraine and tension‐type headache differs between men and women. Female hormones may be an important factor responsible for the sex difference of headache disorders. The level of physical activity showed no association with migraine, but a significantly higher prevalence of tension‐type headache in men with exclusively sedentary activity emerged. Smoking, coffee and alcohol consumption showed no significant associations with the headache disorders. Sleep pattern was significantly associated with migraine and tension‐type headache in both univariate and multivariate analyses. In conclusion, migraine and tension‐type headache seem to be different with regard to a number of endogenous and exogenous factors.

Impact of headache on sickness absence and utilisation of medical services: a Danish population study.

STUDY OBJECTIVE--The aim was to study the extent and type of health service utilisation, medication habits, and sickness absence due to the primary headaches. DESIGN--This was a cross sectional epidemiological survey of headache disorders in a general population. Headache was diagnosed according to a structured interview and a neurological examination using the criteria of the International Headache Society. SETTING--A random sample of 25-64 year-old individuals was drawn from the Danish National Central Person Registry. All subjects were living in the Copenhagen County. PARTICIPANTS--740 subjects participated (76% of the sample); 119 had migraine and 578 had tension type headache. MAIN RESULTS--Among subjects with migraine 56% had, at some time, consulted their general practitioner because of the migraine. The corresponding percentage among subjects with tension type headache was 16. One or more specialists had been consulted by 16% of migraine sufferers and by 4% of subjects with tension type headache. The consultation rates of chiropractors and physiotherapists were 5-8%. Hospital admissions and supplementary laboratory investigations due to headache were rare (< 3%). Half of the migraine sufferers and 83% of subjects with tension type headache in the previous year had managed with at least one type of drug in the current year. Acetylsalicylic acid preparations and paracetamol were the most commonly used analgesics. Prophylaxis of migraine was used by 7%. In the preceding year 43% of employed migraine sufferers and 12% of employed subjects with tension type headache had missed one or more days of work because of headache. Most common was 1-7 days off work. The total loss of workdays per year due to migraine in the general population was estimated at 270 days per 1000 persons. For tension type headache the corresponding figure was 820. Women were more likely to consult a practitioner than men, whereas no significant sex difference emerged as regards absenteeism from work. CONCLUSIONS--The impact of the headache disorders on work performance in the general population is substantial, and the disorders merit increased attention.

Symptomatic and nonsymptomatic headaches in a general population

We assessed the lifetime prevalences of headache disorders in a cross-sectional epidemiologic survey of a representative 25- to 64-year-old general population. We classified the headaches on the basis of a clinical interview and a physical and neurologic examination using the operational diagnostic criteria of the International Headache Society. Lifetime prevalence of idiopathic stabbing headache was 2%, of external compression headache 4%, and of cold stimulus headache 15%. Benign cough headache, benign exertional headache, and headache associated with sexual activity each occurred in 1%. Lifetime prevalence of hangover headache was 72%, of fever headache 63%, and of headache associated with disorders of nose or sinuses 15%. Headaches associated with severe structural lesions were rare. External compression headache, fever headache, headache associated with metabolic disorders, and headache associated with disorders of nose or sinuses all showed significant female preponderance. The symptomatic headaches and headaches unassociated with structural lesions were more prevalent among migraineurs. In subjects with tension-type headache, only hangover headache was overrepresented. There was no association between the headache disorders and abnormal routine blood chemistry or arterial hypertension. In women with migraine, however, diastolic blood pressure was significantly higher than in women without migraine.

Migraine without aura and migraine with aura are distinct clinical entities: a study of four hundred and eighty‐four male and female migraineurs from the general population

The clinical characteristics of migraine without aura (MO) and migraine with aura (MA) were compared in 484 migraineurs from the general population. We used the criteria of the International Headache Society. The lifetime prevalence of MO was 14.7% with a M:F ratio of 1:2.2; that of MA was 7.9% with a M:F ratio of 1:1.5. The female preponderance was significant in both MO and MA. The female preponderance was present in all age groups in MA, but was first apparent after menarche in MO, suggesting that female hormones are an initiating factor in MO, but not likely so in MA. The age at onset of MO followed a normal distribution, whereas the age at onset of MA was bimodally distributed, which could be explained by a composition of two normal distributions. The estimated separation between the two groups of MA was at age 26 years among the females and age 31 years among the males. The observed number of persons with co-occurrence of MO and MA was not significantly different from the expected number. The specificity and importance of premonitory symptoms are questioned, but prospective studies are needed. Bright light was a precipitating factor in MA, but not in MO. Menstruation was a precipitating factor in MO, but not likely in MA. Both MO and MA improved during pregnancy. The clinical differences indicate that MO and MA are distinct entities.

A population‐based analysis of the diagnostic criteria of the International Headache Society

In 740 representative normal subjects a diagnostic headache interview and a neurological examination provided the necessary information to classify headache disorders according to the operational diagnostic criteria of the International Headache Society (IHS). Sixteen per cent (n = 119) had migraine, 78% (n = 578) tension-type headache. In migraineurs, pain was of a pulsating quality in 78%, severe in 85%, unilateral in 62%, and aggravated by routine physical activity in 96%. Tension-type headache was of a pressing quality in 78%, mild or moderate in 99%, bilateral in 90%, and 72% had no aggravation by physical activity. The accompanying symptoms of nausea, photo- and phonophobia occurred frequently and were usually moderate or severe in migraine subjects, and if present in subjects with tension-type headache, they were usually mild. Only two subjects had unclassifiable headache. The IHS Classification is thus exhaustive. The criteria may be improved by mandatory demands to the criterion of pain intensity leaving other features of pain as supportive for the diagnosis and by including graded severity of accompanying symptoms. A specific proposal is given.

Cephalic muscle tenderness and pressure pain threshold in a general population

&NA; Tenderness and pain thresholds in pericranial muscles were studied in a general population. A random sample of 1000 adults aged 25–64 years was drawn as part of the Glostrup Population Studies, and 740 adults were examined. This study was part of a multifacetted, epidemiological study of different headache disorders according to the new headache classification. Manual palpation and pressure pain threshold with an electronic pressure algometer were performed by observers blinded to other information such as the persons history of headache, previous illness and mental state. The muscles most commonly tender to manual palpation were the lateral pterygoid (55%), the trapezius (52%), and the sternocleido‐mastoid muscles (51%). Females were more tender than men in all the muscles examined by manual palpation. In total, the young age group was more tender than the old age group (P = 0.03). Pressure pain thresholds on temporal muscles showed lower thresholds in women than in men (P < 10−3), and in the total population thresholds increased with age (P < 0.05). No side‐to‐side difference in tenderness by manual palpation was found, while the right side showed increased pain thresholds in right‐handed individuals (P < 10−4). No side‐to‐side difference was found in left‐handed persons. This study provides data about the normal population and forms the neccesary basis for evaluating the importance of muscle tenderness in headache subjects and other selected groups.

Questionnaire versus clinical interview in the diagnosis of headache

SYNOPSIS

Prognosis of migraine and tension-type headache A population-based follow-up study

Objective: To determine the prognosis of migraine and tension-type headache and to identify prognostic factors. Methods: Of 740 persons (aged 25 to 64 years) examined in a 1989 Danish cross-sectional headache study, 673 were eligible for follow-up in 2001. All interviews at baseline and at follow-up were conducted by medical doctors and based on the 1988 IHS-criteria. Results: A total of 549 persons (81.6%) participated in the follow-up study. Of 64 migraineurs at baseline, 42% had experienced remission, 38% had low migraine frequency, and 20% had more than 14 migraine days per year (poor outcome) at follow-up. Poor outcome was associated with high migraine frequency at baseline and age at onset younger than 20 years. Among 146 subjects with frequent episodic tension-type headache and 15 with chronic tension-type headache at baseline, 45% experienced infrequent or no tension-type headache (remission), 39% had frequent episodic tension-type headache, and 16% experienced chronic tension-type headache (poor outcome) at follow-up. Poor outcome was associated with baseline chronic tension-type headache, coexisting migraine, not being married, and sleeping problems. Conclusions: The prognosis of migraine, frequent episodic tension-type headache, and chronic tension-type headache was favorable.