Monozygotic twin sisters suffering from cluster headache and migraine without aura

History of cluster headache

Objective:

To summarise the history of cluster headache evolving concepts and growing insights.

Background:

Excruciating pain, activation of the parasympathetic nervous system, and circadian rhythmicity characterise cluster headache attacks.

Results:

We find the oldest descriptions of patients suffering from the disorder in case reports of the 17th and 18th centuries. Only in the 19th and early 20th centuries did physicians start hypothesizing its cause. Initially, many researchers suspected the origin of the pain in peripheral nerves or blood vessels. However, eventually, they understood that the cause of the disease lies in the brain. In 1998, Positron emission tomography studies revealed increased activity of the posterior hypothalamus, whose role remains incompletely understood. Only recently have researchers realised that being diseased implies more than dysfunction. Recent studies analysed the consequences of cluster headache for each patient. Many struggle to deal with the disorder even in the absence of pain.

Conclusion:

Physicians have been aware of this type of pain for at least 300 years. Only when researchers studied pathological anatomy and physiology did knowledge accrue. A more comprehensive picture of the disease severity emerged when they also considered its consequences.

Family History of Cluster Headache: A Systematic Review

Importance

Genetic and environmental factors are thought to contribute to cluster headache, and cluster headache can affect multiple members of a family. A thorough understanding of its inheritance is critical to understanding the pathogenesis of this debilitating disease.

Objective

To systematically review family history rates and inheritance patterns of cluster headache.

Evidence Review

A systematic review was performed in PubMed, Embase, and Cochrane Library. Search criteria were created by a librarian. Articles published between 1985 and 2016, after the publication date of a large review in 1985, were analyzed independently by 2 neurologists to identify family history rates and pedigrees. Pedigrees were analyzed by a genetic counselor.

Findings

A total of 1995 studies were found (1988 through the search criteria and 7 through other means). Forty articles met inclusion criteria: 22 large cohort studies, 1 twin-based study, and 17 case reports or small case series. Across the 22 large cohort studies, the positive family history rate of cluster headache varied between 0% and 22%, with a median of 8.2%. The largest 5 studies, of 1134, 785, 693, 609, and 500 probands each, had a positive family history in 18.0% (numerator not provided), 5.1% (40 of 785 cases), 10.0% (numerator not provided), 2.0% (12 of 609 cases), and 11.2% (56 of 500 cases), respectively. No meta-analysis was performed, given differences in methodologies. Separately, 1 twin-based study examined 37 twin pairs and reported a concordance rate of 5.4% (2 pairs). Finally, 67 pedigrees were identified. Most pedigrees (46 of 67 [69%]) were consistent with an autosomal dominant pattern, but 19 of 67 (28%) were consistent with an autosomal recessive inheritance pattern; 10 pedigrees of probable or atypical cluster headache were identified, and all were consistent with an autosomal dominant inheritance pattern. The sex ratio for cluster headache in identified pedigrees was 1.39 (103:74) in affected men and boys compared with affected women and girls, which is lower than that of the general cluster headache population.

Conclusions and Relevance

Cluster headache is an inherited disorder in a subset of families and is associated with multiple hereditary patterns. There is an unexpectedly high preponderance of women and girls with familial cluster headache; genetic subanalyses limited to female participants are necessary to further explore this observation, because these data are otherwise masked by the higher numbers of male participants with cluster headache. Overall, this systematic review supports the notion that familial cluster headache is likely the result of multiple susceptibility genes as well as environmental factors.

Prevalence of familial cluster headache: a systematic review and meta-analysis

INTRODUCTION

The population rate of familial cluster headache (CH) has been reported to be as high as 20% however this varies considerably across studies. To obtain a true estimate of family history in CH, we conducted a systematic review and meta-analysis of previously published data.

METHODS

Our systematic review involved a search of electronic databases (Medline, EMBASE, PubMed, CINAHL) to identify and appraise studies of interest utilising the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines. To further ameliorate the accuracy of our analysis we included an additional unpublished cohort of CH patients recruited at a tertiary referral centre for headache, who underwent detailed family history with diagnostic verification in relatives. Data was extracted and meta-analysis conducted to provide a true estimation of family history.

RESULTS

In total, we identified 7 studies which fulfilled our inclusion criteria. The estimated true prevalence of CH patients with a positive family history was 6.27% (95% CI:4.65-8.40%) with an overall I² of 73%. Fitted models for gender subgroups showed higher estimates 9.26% (95% CI: 6.29-13.43%) in females. However the I² for the female model was 58.42% and significant (p = 0.047).

CONCLUSION

Our findings estimate a rate of family history in CH to be approximately 6.27% (95% CI: 4.65-8.40%). While estimates were larger for female probands, we demonstrated high heterogeneity in this subgroup. These findings further support a genetic role in the aetiology of CH.

Familial periodicity in a multigenerational family of cluster headache: A case report

I describe an unusual phenotypic phenomenon in two members of a multigenerational family of cluster headache (CH) with anticipation features. The index case, a 44-year-old woman, and her sister, a 40-year-old woman, have a CH phenotype with atypical features as the burning of the nose. Besides identically circadian and circannual features, they present distinct chronobiological features with the onset of the episodic pain attack every third day between them. I propose to entitle this clinical feature “familial periodicity” because of the remarkable phenotypic correlation and probably a similar genotype in the two sisters. Pathophysiologically, this phenomenon may be the result of the dysfunction of the suprachiasmatic nucleus of the hypothalamus on a genetic basis. This is the first case of familial periodicity, which allows extending the clinical spectrum of CH.

Screening of genetic variants in ADCYAP1R1, MME and 14q21 in a Swedish cluster headache cohort

Background

We have genotyped a Swedish cluster headache case-control population for three genetic variants representing the most significant markers identified in a recently published genome wide association study on cluster headache. The genetic variants were two common polymorphisms; rs12668955 in ADCYAP1R1 (adenylate cyclase activating polypeptide 1 receptor type 1), rs1006417, an intergenic variant on chromosome 14q21 and one rare mutation, rs147564881, in MME (membrane metalloendopeptidase).

Results

We screened 542 cluster headache patients and 581 controls using TaqMan real-time PCR on a 7500 fast cycler, and pyrosequencing on a PSQ 96 System. Statistical analysis for genotype and allele association showed that neither of the two common variants, rs12668955 and rs1006417 were associated with cluster headache. The MME mutation was investigated with pyrosequencing in patients, of whom all were wild type.

Conclusion

In conclusion rs12668955 and rs1006417 do not impact the risk of developing cluster headache in the Swedish population. Also, rs147564881 does not seem to be enriched within the Swedish cluster headache patient group.

Familial Cluster Headache. Is Atypical Cluster Headache in Family Members Part of the Clinical Spectrum?

Familial cluster headache (CH) was analysed in 21 Swedish families. Diagnosis was made according to The International Classification of Headache Disorders 2004. We identified 55 affected, of whom 42 had episodic or chronic CH, one had probable CH and 12 had atypical symptoms. The atypical cases did not fulfil the diagnostic criteria for CH, but had clinical symptoms with more resemblance to CH than to migraine or other trigeminal autonomic cephalgia syndromes. The overall male : female ratio was 1.8 : 1. The overall mean age at onset was significantly lower in the second/third generation than in the first generation (mean age at onset 22 vs. 31 years, SD ± 7 vs. 13 years; P < 0.01). This may be anticipation or selection bias, since individuals with late age at onset from the second/third generation may not yet have symptoms. The prevalence of migraine was 24% (13/55), i.e. similar to the prevalence in the general population. The high incidence of atypical CH cases in the Swedish families with other members affected with CH may suggest that the spectrum of CH is broader than previously thought. We suggest that atypical CH in CH families may represent an expanded spectrum of the disease with a common aetiology, i.e. a common genetic background.

Cluster headache and the hypocretin receptor 2 reconsidered: A genetic association study and meta-analysis

Background

Cluster headache is a severe neurological disorder with a complex genetic background. A missense single nucleotide polymorphism (rs2653349; p.Ile308Val) in the HCRTR2 gene that encodes the hypocretin receptor 2 is the only genetic factor that is reported to be associated with cluster headache in different studies. However, as there are conflicting results between studies, we re-evaluated its role in cluster headache.

Methods

We performed a genetic association analysis for rs2653349 in our large Leiden University Cluster headache Analysis (LUCA) program study population. Systematic selection of the literature yielded three additional studies comprising five study populations, which were included in our meta-analysis. Data were extracted according to predefined criteria.

Results

A total of 575 cluster headache patients from our LUCA study and 874 controls were genotyped for HCRTR2 SNP rs2653349 but no significant association with cluster headache was found (odds ratio 0.91 (95% confidence intervals 0.75–1.10), p = 0.319). In contrast, the meta-analysis that included in total 1167 cluster headache cases and 1618 controls from the six study populations, which were part of four different studies, showed association of the single nucleotide polymorphism with cluster headache (random effect odds ratio 0.69 (95% confidence intervals 0.53–0.90), p = 0.006). The association became weaker, as the odds ratio increased to 0.80, when the meta-analysis was repeated without the initial single South European study with the largest effect size.

Conclusions

Although we did not find evidence for association of rs2653349 in our LUCA study, which is the largest investigated study population thus far, our meta-analysis provides genetic evidence for a role of HCRTR2 in cluster headache. Regardless, we feel that the association should be interpreted with caution as meta-analyses with individual populations that have limited power have diminished validity.

The primary headaches: genetics, epigenetics and a behavioural genetic model

The primary headaches, migraine with (MA) and without aura (MO) and cluster headache, all carry a substantial genetic liability. Familial hemiplegic migraine (FHM), an autosomal dominant mendelian disorder classified as a subtype of MA, is due to mutations in genes encoding neural channel subunits. MA/MO are considered multifactorial genetic disorders, and FHM has been proposed as a model for migraine aetiology. However, a review of the genetic studies suggests that the FHM genes are not involved in the typical migraines and that FHM should be considered as a syndromic migraine rather than a subtype of MA. Adopting the concept of syndromic migraine could be useful in understanding migraine pathogenesis. We hypothesise that epigenetic mechanisms play an important role in headache pathogenesis. A behavioural model is proposed, whereby the primary headaches are construed as behaviours, not symptoms, evolutionarily conserved for their adaptive value and engendered out of a genetic repertoire by a network of pattern generators present in the brain and signalling homeostatic imbalance. This behavioural model could be incorporated into migraine genetic research.

[Headaches in the elderly]

ACCORDING TO AGE: It is generally thought that the prevalence of headaches decreases with ageing. However recent studies, with stricter epidemiology and methodology, clearly indicate that this decreases is less obvious than that perceived. PRIMARY AND SECONDARY HEADACHES: In elderly patients, primary headaches and notably migraine (often with altered presentation) are less frequent, even though new authentic cases may appear. However the other types of headache are clearly present. In particular, the incidence and prevalence of secondary headaches slightly increases and they represent up to 30% of all the headaches observed, compared with less than 10% in young or adult patients. The causes of such symptomatic headaches are multiple and it is important to be able to identify them since an aetiological treatment is often possible. REGARDING TREATMENT: The symptomatic treatment of headaches in the elderly follows the same principles as that of younger patients. However, the side effects and drug interactions related to pharmacological treatments can be disastrous in fragilised patients. It is therefore important to emphasize the interest of physical methods of analgesia, particularly adapted to the elderly. Some of these methods have demonstrated their efficacy and are recommended by international consensuses.

Recent findings in headache genetics

PURPOSE OF REVIEW

The progress in headache genetics, especially migraine genetics, recently jumped ahead with some major discoveries.

RECENT FINDINGS

Family and epidemiological studies further strengthen the genetic contribution to migraine and two recent observations gave new molecular insights in the disease. Studies on the genetics of familial hemiplegic migraine revealed, in addition to the previously identified familial hemiplegic migraine type 1 gene CACNA1A on chromosome 19, the familial hemiplegic migraine type 2 gene ATP1A2, encoding the alpha2-subunit of sodium/potassium pumps. Recent genome screens in families with migraine identified susceptibility loci on chromosomes 4, 6, 11 and 14.

SUMMARY

The findings in familial hemiplegic migraine confirm that dysfunction in ion transport is a key factor in migraine pathophysiology and might help us in the elucidation of migraine molecular pathways. The identification of several migraine susceptibility loci underline its genetically complex nature.