Somatic symptoms in headache patients: the influence of headache diagnosis, frequency, and comorbidity

BACKGROUND: Mood disorders of anxiety and depression are well known to be comorbid with primary headache disorders. Less is known of the comorbidity of other somatic symptoms with headache. METHODS: Headache Clinic patients were screened with the Primary Care Evaluation of Mental Disorders (PRIME-MD), a multidimensional psychiatric screening tool. The prevalence of somatic symptoms was compared by headache diagnosis, frequency of severe headache, and psychiatric diagnosis. Follow-up data were obtained 6 months after consultation. RESULTS: Clinical diagnoses and PRIME-MD data were available for 289 patients. Associated somatic symptoms were more frequent in patients with chronic migraine (mean 5.5, P<.001) and chronic daily headache (CDH) (6.3, P=.008) compared to episodic migraine (4.0); in patients with severe headache >2 days per week compared to 2 days per week had significantly higher somatic counts (P=.01). Six-month follow-up data were available for 140 patients. Associated symptoms decreased both for patients with and without decrease in severe headache frequency (mean reduction of 1.0, P=.01 and 0.8, P=.003, respectively). CONCLUSION: Associated somatic symptoms are more common in patients with chronic migraine and CDH, with more frequent severe headaches, and with associated anxiety or depression. Patients with episodic migraine have similar somatic prevalence as a previously studied primary care population. The spectrum of headache disorders may be characterized as showing increasing somatic prevalence as headaches, particularly severe headaches, become more frequent.     

New daily persistent headache in the paediatric population

We conducted a clinic-based study focusing on the clinical features of new-onset chronic daily headaches (CDH) in children and adolescents. The clinical records and headache diaries of 306 children and adolescents were reviewed, to identify 187 with CDH. Relevant information was transferred to a standardized form that included operational criteria for the diagnoses of the headaches. Since we were interested in describing the clinical features of these headaches, we followed the criteria A and B of the 2nd edn of the International Classification of Headache Disorders (ICHD-2) and refer to them as new daily persistent headaches (NDPH) regardless of the presence of migraine features (therefore, this is a modified version of the ICHD-2 criteria). From the 56 adolescents with NDPH, most (91.8%) did not overuse medications. Nearly half (48.1%) reported they could recall the month when their headaches started. NDPH was more common than chronic tension-type headache in both adolescents overusing and not overusing medication. Individuals with NDPH had headaches fulfilling criteria for migraine on an average of 18.5 days per month. On most days, they had migraine-associated symptoms (one of nausea, photophobia or phonophobia)). NDPH is common in children and adolescents with CDH. Most subjects do not overuse medication. Migraine features are common.     

Coping styles of headache sufferers

Psychological factors are important in the chronification and aggravation of headaches. We studied 90 patients suffering from migraine, chronic daily headache (CDH) evolved from migraine, and episodic or chronic tension-type headache (TTH). Emotional, cognitive, and behavioral pain coping were assessed using the Kiel Pain Inventory (KPI), Beck's Depression Inventory, the State-Trait-Anxiety Inventory, and Quality of Life Questionnaire. In addition, the clinical course of headache was analyzed using a validated headache diary. The results were as follows. Firstly, the KPI is reliable internally for the assessment of pain-coping strategy employment among headache patients. Secondly, migraine sufferers were characterized by pronounced psychological abnormalities during the headache phase, demonstrating a less adaptive coping behavior. This was in contrast to the TTH patients, who showed more general distress manifesting in elevated anxiety and lower quality of life. The only factor which appeared to be essential for differentiating between migraine and TTH was the intensity of headache. Thirdly, chronic TTH and CDH evolved from migraine demonstrated more pronounced psychological disabilities and more severe clinical courses of headaches than episodic TTH or nontransformed migraine. The predictor variable for transformation of migraine was impairment of well-being/quality of life, and for transformation of TTH, the frequency of headaches and depression. Finally, analgesic misuse seems to be less important for chronification and transformation of headaches than the degree of psychological disability. This study draws attention to the role of psychological factors in the chronification of TTH and transformation of migraine and provides some recommendations for the behavioral treatment of chronic headaches.     

A retrospective, comparative study on the frequency of abuse in migraine and chronic daily headache

OBJECTIVE: To assess and contrast the relative frequency of a past history of physical and/or sexual abuse in patients with chronic daily headache (CDH) versus migraine. BACKGROUND: A number of risk factors have been identified as risk factors for chronification of headache disorders. Limited data exist regarding the influence of physical and/or sexual abuse on primary headache disorders. METHODS: This was a retrospective chart review of 183 consecutive new headache patients seen from December 2004 through August 2005 at an outpatient tertiary-care center. Patients were included in the study if they had chronic daily headache (with criteria for medication over-use headache or chronic migraine), or migraine with or without aura. A history of physical and/or sexual abuse was systematically asked of all headache patients at their first visit in the clinic. This information was then transferred to a semi-standardized form and the relative frequency of abuse in both groups contrasted. RESULTS: Of the 161 patients included in the study, 90.1% were female with a mean age of 36.4 +/- 12.0. A total of 59.0% of the patients were diagnosed with CDH and 41.0% were diagnosed with migraine. Overall, 34.8% of all patients, 40.0% of CDH patients, and 27.3% of migraine patients had a history of physical and/or sexual abuse. The relative frequency of a history of physical and/or sexual abuse was higher in the CDH group as compared to the migraine group (P = .048). CONCLUSION: The relative frequency of abuse is higher in CDH sufferers than migraineurs, suggesting that physical and sexual abuse may be risk factors for chronification.     

The International Headache Society (IHS) Headache Classification as applied to a headache clinic population

Four hundred patients attending a headache clinic were classified using the IHS criteria. The majority required more than two, often three or four, diagnoses. Even though migraine was the most common diagnosis, only 1/4 of those with a migraine diagnosis had it as the only diagnosis. Seventy-five percent of migraine patients had coexistent chronic tension-type headache (CTTH), drug-induced headache or both. Ninety-six percent of patients diagnosed as having migraine with aura also suffered from migraine without aura. More than 1/3 of patients (37.7%) attending the clinic suffered from chronic daily headache (CDH) (chronic cluster headache excluded), which is not included as a separate entity in the IHS classification. Pure CTTH formed only a small minority of CDH, whereas 86.6% of CDH had migraine as one of the diagnoses. Drug-induced headache was a prominent second or third diagnosis. The advantages and disadvantages of multiple verses single diagnosis in CDH and the need to recognize the natural history of headache disorders in the classification are discussed.     

Chronic daily headache in a primary care population: prevalence and headache impact test scores

BACKGROUND: Population-based surveys estimate the prevalence of chronic daily headache (CDH) in the general community to be approximately 4%. The prevalence of CDH among patients seen in the primary care setting in the United States, however, is unknown. PURPOSE: To estimate the prevalence and associated burden of suffering of CDH in a primary care patient population. METHODS: Cross-sectional survey of a randomly selected sample of 1500 adult patients in an academic Family Medicine Center was done. Outcome measures include self-reported headache frequency and Headache Impact Test scores. RESULTS: Completed questionnaires were returned by 853 (57%) patients. The mean age of respondents was 49 years (SD = 16), with a range of 18 to 94 years. Two hundred ninety-six (58%) patients reported having had 1 or more severe headaches in the past month. Seventy-four (9%) patients reported a frequency of headache consistent with CDH, defined as the occurrence of headache 15 or more days in the past month. Twenty-four patients (32%) with CDH either believed that none of their doctors know that they experienced headaches or were not sure if their doctors were aware of their headaches, and 21 (28%) reported that they have not needed a doctor's care for their headaches. CONCLUSIONS: The prevalence of CDH is greater among a primary care patient population compared to the general community. A substantial proportion of patients with CDH do not bring their headaches to the attention of their health-care providers. In light of the advances in the development of effective medications for migraines and the growing body of evidence implicating medications as a contributing cause of CDH, it may be appropriate to encourage patients to inform their health-care providers about their headaches and to encourage providers to identify patients with frequent headaches.     

Chronic daily headache in children and adolescents: a clinic based study from India

Chronic Daily Headache (CDH) is uncommon in Indian children compared to their adult counterpart. This is a retrospective study looking at the headache phenomenology of CDH in Indian children and adolescents. The validity of the case definitions of subtypes of chronic primary headaches mentioned in the IHS 2004 classification have been evaluated. 22 children (age range 8-15 years; M : F-16 : 6) diagnosed as having primary CDH using a modified definition seen between 2002 and 2003 have been studied. CDH has been defined as daily or near daily headaches > 15d/month for > 6 weeks. The rationale for this modified definition has been discussed. Majority of children (15/22) had a more or loss specified time of onset of regular headache spells resembling New Daily Persistent Headache (NDPH) but did not fulfil totally the diagnostic criteria of NDPH as laid down by IHS 2004. In all cases headache phenomenology included a significant vascular component. Headache phenomenology closely resembled Chronic Tension Type Headache (CTTH) in 4 patients and Chronic Migraine in 3 patients. However, in no patient in these groups, a history of evolution from the episodic forms of the diseases could be elicited. Heightened level of anxiety mostly related to academic stress and achievement was noted in the majority (19/22). Only a minority of patients (3/22) had anxiety and depression related to interpersonal relationships in the family. Medication overuse was not implicated in any patient. CDH in children in India is very much different from CDH in adults with the vast majority of patients exhibiting overlapping features of migraine and tension-type headache. There is need for a modified diagnostic criteria and terminology for chronic primary headaches in children.     

The tension headache component of chronic daily headache

Chronic daily headache (CDH) is an overarching term that includes multiple types of frequent primary headaches that are not trigeminal-autonomic cephalgias. The components of typical CDH can be divided into a more severe or “big” headache and a less severe or “little” headache. The big headaches tend to have features of migraine while the little headaches have features of tension-type headache (TTH). Whether this represents a spectrum or continuum or whether it is the superimposition of two unique headache entities is open to debate. For subjects with big and little headache, the concept that the TTH component is part of a spectrum seems likely. Subjects with only TTH and no migrainous component seem to represent a different entity, pure chronic TTH. These patients have a daily moderate headache that is poorly responsive to current therapies and appears to be a different TTH than the migraine tension type of CDH. The TTH component of CDH may represent multiple subdivisions of TTH.     

Dextroamphetamine pilot crossover trials and n of 1 trials in patients with chronic tension-type and migraine headache

OBJECTIVE: To examine the preventive effects of dextroamphetamine in select small groups of patients with chronic tension-type and migraine headache. BACKGROUND: Neither amphetamine nor methylphenidate is used as a headache preventive. This study was undertaken after a chance observation led one of us to prescribe dextroamphetamine with apparent successes in specific patients with chronic tension-type or migraine headaches. METHODS: Two pilot trials were done. Trial 1 tested patients who were taking dextroamphetamine, while Trial 2 tested patients who had never taken this drug. Each trial obtained full data on eight subjects with chronic tension-type headache and eight subjects with migraine headache. A randomized, double-blinded, controlled, multiple-crossover design was used. Subjects took capsules containing dextroamphetamine or equi-stimulatory caffeine (the control) during four alternating 20-day periods. Trial 1 subjects took their pretrial dextroamphetamine dose at breakfast and lunch. Trial 2 subjects took 10 mg at these times. Subjects recorded the integer from 0 to 3 that represented their headache intensity during the previous 24 hours. The subject's data were the average daily headache grade for the two dextroamphetamine periods and for the two caffeine periods. The differential effect of amphetamine and caffeine on each group of eight subjects and on each individual was analyzed by t-tests. RESULTS: In both trials, the tension-type and migraine groups had lower mean daily headache grades in the amphetamine than in the caffeine periods. P values for these differences indicated that there were real drug effects, on the average, in the migraine groups (P<.05) and suggestive but inconclusive effects in the tension-type groups (P<.10). The individual n of 1 analyses showed that five tension-type and three migraine subjects in Trial 1 and three tension-type and three migraine subjects in Trial 2 had considerably lower mean daily headache grades on amphetamine with P values indicating, at various levels of significance (from P<.05 to P<.001), real amphetamine effects. Twelve of the remaining 18 patients had lower, albeit not significant, mean daily grades with amphetamine. No subject in either trial had a significantly lower mean daily headache grade on caffeine. CONCLUSIONS: Dextroamphetamine had real preventive effects on chronic tension-type and migraine headaches in some subjects. These results should encourage other investigators to study its effects on these headaches.     

Analysis of the patients attending a specialist UK headache clinic over a 3-year period

OBJECTIVE: This study analyzed the profile of patients who attended a specialist UK headache clinic over a 3-year period. METHODS: An audit was conducted of the clinical records of patients attending the specialist headache clinic at King's College, London, between January 1997 and January 2000. Data were collected for diagnoses given, current medications taken, medications prescribed and recommended, and investigations conducted. Results were calculated as numbers and proportions of patients for the 3-year period and for the 3 separate 12-month periods. RESULTS: A total of 458 patients were included in the audit. Most patients were diagnosed as having chronic daily headache (CDH, 60%) or migraine (33%). Prior to the clinic visit, most patients with CDH and migraine treated their headaches with analgesics, and there was little use of prophylactic medication. In the clinic, 74% of patients with CDH and 85% of migraineurs were prescribed prophylactic medication, and 81% of migraineurs were given triptans for acute treatment. Diagnostic testing was performed in 12% of the patients, and all results were normal or negative. CONCLUSIONS: CDH and migraine were the most common headache types encountered in this UK secondary-care clinic. Review of treatment patterns used prior to the initial clinic evaluation suggests that management of CDH and migraine in UK primary care is suboptimal, and educational initiatives are needed to improve headache management.     

Epidemiology of chronic daily headache

Daily or near-daily headache is a widespread problem in clinical practice. The general term of chronic daily headache (CDH) encompasses those primary headaches presenting more than 15 days per month and lasting more than 4 hours per day. CDH includes transformed migraine (TM), chronic tension-type headache (CTTH), new daily persistent headache (NDPH), and hemicrania continua (HC). Around 40% of patients attending a specialized headache clinic meet CDH diagnostic criteria, of which 80% are women. In these clinics about 60% of patients suffer from TM, 20% from CTTH, and 20% meet NDPH criteria. Most, some 80%, overuse symptomatic medications. One should be very cautious on extrapolating these numbers to the general population. CDH prevalence in the general population seems to be around 4% to 5% (up to 8% to 9% for women). Regarding the prevalence of CDH subtypes, NDPH is rare (0.1%), whereas the prevalence of TM (1.5% to 2%) and CTTH (2.5% to 3%) is clearly higher. In contrast to data from specialized clinics, only around a quarter of CDH subjects in the general population overuse analgesics; the prevalence of CDH subjects with analgesic overuse being 1.1% to 1.9% of the general population. Most of these patients with analgesic overuse are TM patients.     

The classification of chronic daily headache in adolescents--a comparison between the second edition of the international classification of headache disorders and alternative diagnostic criteria

OBJECTIVES: To compare the second edition of the International Classification of Headache Disorders (ICHD-2) and the Silberstein-Lipton (S-L) criteria in the classification of adolescents with chronic daily headache (CDH). METHODS: We reviewed the clinical records and the headache diaries of 170 adolescents (13 to 17 years) seen between 1998 and 2003 at a headache center. Relevant information was transferred to a standardized form that included operational criteria for the ICHD-2. CDH subtypes were classified according the criteria proposed by S-L into transformed migraine (TM) with (TM+) and without medication overuse (TM-), chronic tension-type headache (CTTH), new daily persistent headache (NDPH), and hemicrania continua (HC). RESULTS: From the 69 patients with TM- according the S-L criteria, most (71%) could be classified as chronic migraine (CM), while a minority of patients required a combination of diagnosis, mainly migraine and CTTH (14.4%). Of the patients with TM+, just 39.6% met the criteria for probable CM (PCM) with probable medication overuse (PMO). If instead of 15 migraine days per month, we considered 15 or more days of migraine or probable migraine, 84% of the subjects with TM- and 68.7% of those with TM+ could be classified. Of the 27 subjects classified as NDPH without medication overuse according to the S-L system, the majority (51.2%) were also classified as NDPH according the ICHD-2. Interestingly, three (11.1% of the subjects with NDPH without medication overuse) were classified as CM in the ICHD-2 because these patients had an abrupt onset of 15 or more days of migraine per month. All patients with NDPH with medication overuse according to the S-L criteria required a combination of diagnoses in the ICHD-2. All subjects with CTTH received a single diagnosis in both classification systems. CONCLUSIONS: (i) Among adolescents with TM, the majority (58.1%) could be classified as CM, according to the ICHD-2. These results were driven by TM without medication overuse. (ii) If the ICHD-2 criteria for CM are revised to require 15 days of migraine or probable migraine, the proportion of patients with TM- who meet the criteria for CM increases from 71% to 84%; for TM+, the proportion with probable chronic migraine and PMO increases from 30% to 68%. (iii) About half of the patients with NDPH according to the S-L criteria have too many migraine features to meet ICHD-2 criteria for NDPH.     

An epidemiological study of headache in Florianopolis, Brazil

The aim of this study was to estimate the 1-year prevalence of headache, migraine, tension-type headache (TTH) and chronic daily headache (CDH), and the degree of association of migraine with some sociodemographic characteristics of the population of Florianopolis, Brazil. This is a cross-sectional, door-to-door, population-based study. In 300 randomly selected households, 625 subjects, aged 15-64 years, responded to a structured questionnaire. The 1-year prevalence of headache was 80.8%, of migraine 22.1%, of TTH 22.9%, and of CDH 6.4%. Migraine and CDH were significantly more prevalent in females than in males. Migraine was significantly associated with the following variables: low household income, low electricity consumption, and divorced or widowed marital status. We have shown high prevalences of migraine and CDH in Florianopolis, close to the higher rates of previous studies. There was a preponderance of migraine in females, divorced or widowed, with a low socioeconomic level.     

Treatment of chronic daily posttraumatic headache with divalproex sodium

OBJECTIVE: To determine the effectiveness of divalproex sodium in the treatment of chronic daily posttraumatic headaches. BACKGROUND: Divalproex sodium has been found to be useful for the treatment of migraine and chronic daily headache. No studies have been done to evaluate effectiveness in posttraumatic headache. METHODS: A retrospective review was done of 100 patients treated with divalproex for chronic daily posttraumatic headache of 2 months or longer. RESULTS: Sixty percent of patients with chronic posttraumatic headache had mild to moderate improvement in their headaches after at least 1 month of divalproex sodium. Forty percent either showed no response (26%) or discontinued treatment because of side effects (14%). Fifty-eight percent of patients showing improvement had a change in headache pattern from daily to episodic. CONCLUSIONS: Divalproex sodium appears to be safe and effective for treatment of patients with persistent, chronic daily posttraumatic headaches.     

Amitriptyline in the prophylactic treatment of migraine and chronic daily headache

(Headache 2011;51:33‐51) Objective and Background.— Amitriptyline is one of the most commonly used medications in migraine prophylaxis. There have been relatively few placebo‐controlled studies of amitriptyline in migraine prophylaxis or in treatment of chronic daily headache (CDH). This report deals with a large placebo‐controlled trial of amitriptyline vs placebo of 20 weeks duration that included subjects with intermittent migraine (IM) as well as CDH. The study was carried out between 1976 and 1979; however, results have never been fully reported. Methods.— Patients with a history of migraine as defined by the 1962 Ad Hoc Committee report were recruited for this study. Subjects had at least 2 headaches per month, and no limit was placed on the number of headaches per month that could be experienced. The study format included a 4‐week baseline period (Period A) in which all subjects received placebo in a dose of 2 pills per day for one week, 3 pills per day for one week and then 4 pills per day for 2 weeks. Subjects with at least 2 migraine headaches in this period were then entered into Period B and randomized into either amitriptyline or placebo tracks. Medication consisted of identical tablets containing either 25 mg amitriptyline or placebo. Period B was 4 weeks in duration with dose titration identical to Period A. The dose could be reduced if necessary to reduce side effects. The minimum dose was one pill per day. Period C was a 12‐week maintenance or stabilization period in which the patient continued the dose established by week 8 with visits at weeks 12, 16, and 20. Patients kept a headache calendar that was used for data collection. Headache frequency (per month), severity, and duration (hours) were the primary measurement parameters employed for data analysis. Results.— For the entire group, 391 subjects were entered into Period A, 338 were randomized into Period B, 317 (81%) subjects completed the first post‐randomization visit (8 weeks), 255 (65%) completed week 12, 210 (54%) completed week 16, and 186 (48%) completed week 20. Using headache frequency and evaluating parameters of (a) improvement, (b) no change, or (c) worsening relative to baseline, there was a significant improvement in headache frequency for amitriptyline over placebo at 8 weeks (P = .018) but not at 12, 16, or 20 weeks. When amitriptyline and placebo patients were compared for headache frequency at 8, 12, 16, and 20 weeks to their own placebo stabilization period at 4 weeks, statistically significant improvement vs worsening was seen in headache frequency at each evaluation point for both amitriptyline and placebo groups (P ≤ .01) reaching 50% reporting a decrease in frequency in each group and approximately 10% reporting worsening by week 20. There were no significant differences in headache severity or duration between amitriptyline and placebo groups at anytime during the study. Within the study sample, there were 36 amitriptyline and 22 placebo subjects who had headaches ≥17 days/month that fit the current definition of CDH by the Silberstein‐Lipton criteria. These were analyzed separately as a subgroup for comparison of amitriptyline vs placebo using a metric of (1) no change or worsening; (2) up to a 50% improvement; and (3) ≥50% improvement in headache frequency. Amitriptyline was superior to placebo in number with improvement in frequency of ≥50% at 8 weeks (25% vs 5% [P = .031]) and at 16 weeks (46% vs 9% [P = .043]). There was a trend for amitriptyline to be superior to placebo at 12 and 20 weeks but this did not reach significance. Conclusions.— In this study, using headache frequency as the primary metric, for the entire group, amitriptyline was superior to placebo in migraine prophylaxis at 8 weeks but, because of a robust placebo response, not at subsequent time points. For the subgroup with CDH, amitriptyline was statistically significantly superior to placebo at 8 weeks and 16 weeks with a similar but nonsignificant trend at 12 and 20 weeks. Compared with placebo amitriptyline is effective in CDH. Amitriptyline was also significantly effective in IM compared intragroup to its own baseline; however, placebo was equally effective in the same analysis. The reason for the robust placebo response in the IM group is not clear, but has been occasionally reported.     

Chronic daily headache in a tertiary care population: correlation between the International Headache Society diagnostic criteria and proposed revisions of criteria for chronic daily headache

The International Headache Society (IHS) has been criticized for its approach to classification of chronic daily headache (CDH); Silberstein and Lipton criteria provide an alternative to this approach. The aim of this study is to apply the alternative diagnostic approaches to a sample of CDH patients consulting in specialty care. Our sample consisted of 638 patients with CDH. Patients were classified according to both classification systems. Patients were predominantly female (65.0%), with ages ranging from 11 to 88 years. According to the Silberstein and Lipton classification, we found eight different diagnoses. The most common diagnosis was chronic migraine (87.4%), followed by new daily persistent headache (10.8%). Just six patients had chronic tension-type headache (CTTH). Applying the IHS criteria we found 14 different diagnoses. Migraine was found in 576 (90.2%) patients. CTTH occurred in 621 (97.3%), with only 10 (1.57%) having this as the sole diagnosis. We conclude that both systems allow for the classification of most patients with CDH when daily headache diaries are available. The main difference is that the IHS classification is cumbersome and requires multiple diagnoses. The Silberstein and Lipton system is easier to apply, and more parsimonious. These findings support revision of the IHS classification system to include chronic migraine.     

Chronic daily headaches: clinical profile in Indian patients

Chronic daily headache (CDH) remains a relatively unexplored entity in India. Misconceptions are common, unnecessary investigations often done and inappropriate therapy prescribed. Analgesic overuse is seldom recognized. The present report appears to be the first of its kind from India. CDH has been defined as headaches occurring more than 15 days per month for more than 3 months (secondary causes excluded). Over 2 years (1998-1999) 849 cases (49.6% of all primary headaches) were seen. More than 1 year's follow-up data were available in 205 subjects (M 34; F 171). The distribution of these was as follows: (i), chronic tension-type headache (CTH), 33 (16.1%); (ii), chronic/transformed migraine (TM), 169 (82.4%); (iii), new persistent CDH, 3 (1.5%). There were 169 cases of TM (M : F 1 : 4.7; age 26-58 years). History of past episodic migraine was present in all. Transformation had been gradual (89.4%) or acute (10.6%). Possible factors in transformation included psychological stress (44.4%), analgesic overuse (28.4%), ergot overuse (4.1%). HRT seemed to be implicated in three female subjects. Analgesic overuse was limited between intake of 600 and 2400 mg of aspirin equivalent per day (mean 735 mg). Ergot overuse varied between 1 and 3 mg/day of ergotamine for > or = 3 days/week. With medical therapy approximately 70% TM and 40% CTH patients noted significant improvement. About 80% of these relapsed on therapy withdrawal. CDH in India is not uncommon. Analgesic/ergot overuse needs to be recognized early. The average dose of analgesic implicated in CDH seems much less compared with that reported in the West.     

Kaplan Award 1998. Epidemiology of chronic daily headache in the general population

Background and Objectives.—Although chronic daily headache, mainly transformed migraine, is an important reason for consultation in headache clinics, its actual prevalence is unknown. This study analyzes the prevalence of the different types of chronic daily headache in an unselected population.
Methods.—A questionnaire exploring headache frequency was distributed to 2252 unselected subjects. Those having headache 10 or more days per month were given a headache diary and were seen by a neurologist who classified their headaches. The varieties of chronic daily headache were classified according to the second revision of IHS criteria proposed by Silberstein et al published in Neurology 1996;47:871.
Results.—The questionnaire was returned by 1883 subjects (83.5%). One hundred thirty-five admitted to headache 10 or more days per month. Chronic daily headache criteria were fulfilled by 89 individuals (4.7%). Eighty were women. Forty-two (47.2% of subjects with chronic daily headache and 2.2% of all subjects) had chronic tension-type headache. Analgesic overuse was found in 8 (17%). Transformed migraine was diagnosed in 45 (50.6% of subjects with chronic daily headache and 2.4% of all subjects). Fourteen (31.1%) individuals with this form of chronic daily headache overused ergots or analgesics. The remaining 2 cases in this series met the criteria of new daily persistent headache. No one was diagnosed as having hemicrania continua.
Conclusions.—Almost 5% of the general population (9% of women) suffers from chronic daily headache, the proportion of chronic tension-type headache and transformed migraine being quite similar. Less than one third overuse analgesics. The prevalence of chronic daily headache subtypes shown here differs from data obtained from headache clinics, emphasizing that caution is needed in extrapolating data from specialized units to the general population.     

Chronic daily headache: a time perspective

OBJECTIVE: To determine the development and outcome of chronic daily headache in 258 headache practice patients, consisting of 50 men and 208 women. Chronic daily headache was defined as headaches occurring on at least 5 days per week for at least 1 year. METHODS: Two hundred fifty-eight patients with headache were interviewed and evaluated. Ninety-one patients were contacted by telephone for follow-up. RESULTS: Twenty-two percent of the patients had daily headaches from the onset, and 78% initially experienced intermittent headaches. Of the patients with initially intermittent headaches, 19% experienced an abrupt transition into daily headaches and 81%, a gradual one. In the patients with gradual transition, the transition of the initial, intermittent headaches into daily headaches took an average of 10.7 years. The initial headaches were mild in 33% of the patients and severe in 67%. The severe headaches were associated with nausea and vomiting significantly more often than the mild ones. However, the daily headaches that these patients ultimately developed were the same, regardless of whether the initial headaches were mild or severe. The patients who gradually developed daily headaches from initially intermittent headaches were contacted to determine the outcome of their headaches. Of these patients, 33% continued to have daily headaches and 67% again experienced intermittent headaches. Of the latter group, 88% of the patients who now had migraine also had migraine initially.     

Predictors of response to botulinum toxin type A (BoNTA) in chronic daily headache

OBJECTIVE: To evaluate predictors of response to botulinum toxin type A (BoNTA; BOTOX, Allergan Inc., Irvine, CA, USA) in patients with chronic daily headache (CDH). BACKGROUND: Chronic migraine (CM) and chronic tension-type headache (CTTH) form the majority of CDH disorders. Controlled trials indicate that BoNTAis effective in reducing the frequency of headache and number of headache days in patients with CDH disorders. A recent migraine study found that patients with imploding or ocular types of headaches were responders to BoNTA, whereas those with exploding headaches were not. To date, there are no data on factors that might predict response to BoNTA in patients with CDH. METHODS: A total of 71 patients with CM and 11 patients with CTTH were treated with 100 units BoNTA. Every patient received at least 2 sets of injections at intervals of 12-15 weeks; fixed sites, fixed dose, and "follow-the-pain" approaches were used for the injections. A detailed medical history was taken for each patient in addition to recording Migraine Disability Assessment Scale (MIDAS) scores at baseline and every 3 months after each set of injections. Headache frequency was assessed throughout the study from baseline to weeks 24-27. Patients recorded the frequency, severity, and duration of headaches in Headache Diaries. Patients were divided into responders (> or = 50% reduction in both headache frequency and MIDAS scores compared with baseline) and nonresponders (< 50% reduction in either of the above variables). Variables analyzed for predictors of response include headache that is predominantly unilateral or bilateral in location, presence of cutaneous allodynia (scalp allodynia), and presence of pericranial muscle tenderness (also referred to as muscle allodynia). Chi-square analysis was used for parallel-group comparisons (proportion of CM responders vs proportion of CM nonresponders and proportion of CTTH responders vs proportion of CTTH nonresponders). RESULTS: In the CM group, 76.1% (54 /71) of patients were responders to BoNTA, of which 68.5% (37/54) had headache that was predominantly unilateral in location and the remaining 31.5% (17/54) had headache that was predominantly bilateral in location (both P < .01 vs CM nonresponders). Of the 23.9% (17/71) CM nonresponders, 76.5% (13/17) reported predominantly bilateral headache and in the remaining 23.5% (4/17) the headache was unilateral. In the CM responders group, 81.5% (44/54) had clinically detectable scalp allodynia, while pericranial muscle tenderness was present in 61.1% (33/54) (both P < .01 vs CM nonresponders). The presence of scalp allodynia and pericranial muscle tenderness in the CM nonresponders was 11.8% (2/17) and 17.6% (3/17), respectively. In the CTTH group where all patients (100%, 11/11) had bilateral headache, 36.4% (4/11) of patients were responders to BoNTA. All of those CTTH responders (100%, 4/4) had pericranial muscle tenderness (P < .05 vs CTTH nonresponders). None of the CTTH nonresponders had pericranial muscle tenderness. No clinically significant serious adverse events (AEs) were reported. Mild AEs, eg, injection-site pain that persisted for 1-9 days, were reported in 11 patients. One patient had transient brow ptosis. CONCLUSIONS: A greater percentage of patients with CM responded to BoNTA than patients with CTTH. Headaches that were predominantly unilateral in location, presence of scalp allodynia, and pericranial muscle tenderness appear to be predictors of response to BoNTA in CM, whereas in CTTH, pericranial muscle tenderness may be a predictor of response.