Cluster Headache Genomewide Association Study and Meta-Analysis Identifies Eight Loci and Implicates Smoking as Causal Risk Factor

OBJECTIVE

The objective of this study was to aggregate data for the first genomewide association study meta-analysis of cluster headache, to identify genetic risk variants, and gain biological insights.

METHODS

A total of 4,777 cases (3,348 men and 1,429 women) with clinically diagnosed cluster headache were recruited from 10 European and 1 East Asian cohorts. We first performed an inverse-variance genomewide association meta-analysis of 4,043 cases and 21,729 controls of European ancestry. In a secondary trans-ancestry meta-analysis, we included 734 cases and 9,846 controls of East Asian ancestry. Candidate causal genes were prioritized by 5 complementary methods: expression quantitative trait loci, transcriptome-wide association, fine-mapping of causal gene sets, genetically driven DNA methylation, and effects on protein structure. Gene set and tissue enrichment analyses, genetic correlation, genetic risk score analysis, and Mendelian randomization were part of the downstream analyses.

RESULTS

The estimated single nucleotide polymorphism (SNP)-based heritability of cluster headache was 14.5%. We identified 9 independent signals in 7 genomewide significant loci in the primary meta-analysis, and one additional locus in the trans-ethnic meta-analysis. Five of the loci were previously known. The 20 genes prioritized as potentially causal for cluster headache showed enrichment to artery and brain tissue. Cluster headache was genetically correlated with cigarette smoking, risk-taking behavior, attention deficit hyperactivity disorder (ADHD), depression, and musculoskeletal pain. Mendelian randomization analysis indicated a causal effect of cigarette smoking intensity on cluster headache. Three of the identified loci were shared with migraine.

INTERPRETATION

This first genomewide association study meta-analysis gives clues to the biological basis of cluster headache and indicates that smoking is a causal risk factor. ANN NEUROL 2023;94:713-726.

Binational confidential enquiry of maternal deaths due to postpartum hemorrhage in France and the Netherlands: Lessons learned through the perspective of a different context of care

OBJECTIVE

To learn lessons for maternity care by scrutinizing postpartum hemorrhage management (PPH) in cases of PPH-related maternal deaths in France and the Netherlands.

METHODS

In this binational Confidential Enquiry into Maternal Deaths (CEMD), 14 PPH-related maternal deaths were reviewed by six experts from the French and Dutch national maternal death review committees regarding cause and preventability of death, clinical care and healthcare organization. Improvable care factors and lessons learned were identified. CEMD practices and PPH guidelines in France and the Netherlands were compared in the process.

RESULTS

For France, new insights were primarily related to organization of healthcare, with lessons learned focusing on medical leadership and implementation of (surgical) checklists. For the Netherlands, insights were mainly related to clinical care, emphasizing hemostatic surgery earlier in the course of PPH and reducing the third stage of labor by prompter manual removal of the placenta. Experts recommended extending PPH guidelines with specific guidance for women refusing blood products and systematic evaluation of risk factors. The quality of CEMD was presumed to benefit from enhanced case finding, also through non-obstetric sources, and electronic reporting of maternal deaths to reduce the administrative burden.

CONCLUSION

A binational CEMD revealed opportunities for improvement of care beyond lessons learned at the national level.

The International Network of Obstetric Survey Systems study of uterine rupture: a descriptive multi-country population-based study

OBJECTIVE

International comparison of complete uterine rupture.

DESIGN

Descriptive multi-country population-based study.

SETTING

International.

POPULATION

International Network of Obstetric Survey Systems (INOSS).

METHODS

We merged individual data, collected prospectively in nine population-based studies, of women with complete uterine rupture, defined as complete disruption of the uterine muscle and the uterine serosa, regardless of symptoms and rupture of fetal membranes.

MAIN OUTCOME MEASURES

Prevalence of complete uterine rupture, regional variation and correlation with rates of caesarean section (CS) and trial of labour after CS (TOLAC). Severe maternal and perinatal morbidity and mortality.

RESULTS

We identified 864 complete uterine ruptures in 2 625 017 deliveries. Overall prevalence was 3.3 (95% CI 3.1-3.5) per 10 000 deliveries, 22 (95% CI 21-24) in women with and 0.6 (95% CI 0.5-0.7) in women without previous CS. Prevalence in women with previous CS was negatively correlated with previous CS rate (ρ = -0.917) and positively correlated with TOLAC rate of the background population (ρ = 0.600). Uterine rupture resulted in peripartum hysterectomy in 87 of 864 women (10%, 95% CI 8-12%) and in a perinatal death in 116 of 874 infants (13.3%, 95% CI 11.2-15.7) whose mother had uterine rupture. Overall rate of neonatal asphyxia was 28% in neonates who survived.

CONCLUSIONS

Higher prevalence of complete uterine ruptures per TOLAC was observed in countries with low previous CS and high TOLAC rates. Rates of hysterectomy and perinatal death are about 10% following complete uterine rupture, but in women undergoing TOLAC the rates are extremely low (only 2.2 and 3.2 per 10 000 TOLACs, respectively.) TWEETABLE ABSTRACT: Prevalence of complete uterine rupture is higher in countries with low previous CS and high TOLAC rates.

Caesarean section rates in subgroups of women and perinatal outcomes

OBJECTIVES

To identify factors that are associated with a relatively low caesarean section (CS) rate by examining the CS rate in various subgroups in the Netherlands.

DESIGN

Cross-sectional analysis.

SETTINGS

the Netherlands.

POPULATION

A total of 685 452 births in the Netherlands Perinatal Registry from 2007 to 2010.

METHODS

A modified classification system for CS was used to categorise all women into ten groups. Labour management, mode of delivery, maternal and neonatal morbidity and mortality were assessed according to these ten groups.

MAIN OUTCOME MEASURES

Caesarean section, labour induction, instrumental delivery, postpartum haemorrhage, perineal laceration, duration of second stage of labour, Apgar score, fetal and neonatal mortality.

RESULTS

Total CS rate was 15.6%. Term, nulliparous and parous women with a singleton pregnancy of a fetus in cephalic position and spontaneous onset of labour had CS rates of 9.6 and 1.9% and instrumental birth rates of 19.4 and 2.4%, respectively; 17.3% of births were induced. Among women with a previous CS and term, singleton pregnancies with a fetus in cephalic presentation, 71% had trial of labour, of which 75% had a successful vaginal birth. Of women with multiple gestation, 43% had CS. Women with CS due to 'failure to progress' in the second stage of labour had a median duration of second-stage pushing of almost 2 hours in nulliparas and >90 minutes in parous women.

CONCLUSIONS

Several obstetric practice patterns may have contributed to the relatively low overall CS rate in the Netherlands: a relatively low CS rate in term, singleton pregnancies of a fetus in cephalic position and spontaneous onset of labour, relatively low rate of labour induction, a high rate of a trial of labour after a previous CS, the use of vacuum and forceps, and a high proportion of women being taken care of by midwives.

TWEETABLE ABSTRACT

The Netherlands has several practice patterns that may have contributed to its relatively low CS rate.

Headache prevalence related to smoking and alcohol use. The Head-HUNT Study

The aim of this study was to examine a possible association between smoking, alcohol and headache in a large population-based cross-sectional study. A total of 51,383 subjects completed a headache questionnaire and constituted the 'Head-HUNT' Study. Questionnaire-based information on smoking was available in 95% and on alcohol in 89% of the individuals. Associations were assessed in multivariate analyses, estimating prevalence odds ratios (ORs) with 95% confidence intervals (CI). Prevalence rates for headache were higher amongst smokers compared with never smokers, most evident for those under 40 years smoking more than 10 cigarettes per day (OR 1.5, 95% CI 1.3-1.6). Passive smoking was also associated with higher headache prevalence. For alcohol use, there was a tendency of decreasing prevalence of migraine with increasing amounts of alcohol consumption compared with alcohol abstinence. Only with regard to symptoms indicating alcohol overuse, a positive association with frequent headache was found. The association between headache and smoking found in the present study raises questions about a causal relationship, e.g. that smoking causes headache or that it allays stress induced by headache. The observed negative association between migraine and alcohol consumption is probably explained by the headache precipitating properties of alcohol.

Five-year survival in patients with endometrioid carcinoma of the ovary versus those with serous carcinoma

BACKGROUND

Ovarian carcinoma is the most deadly of gynecologic malignancies. Controversy exists as to whether different histologic types have a different prognosis. The goal of this study was to determine whether patients with endometrioid carcinoma of the ovary have a different prognosis than patients with serous carcinoma.

METHODS

Available records for all patients on the gynecologic oncology service with epithelial ovarian carcinoma from January 1, 1981 through December 31, 1989, were reviewed. Patients with endometrioid ovarian carcinomas were matched with patients with serous carcinoma with regards to age, grade, stage, and level of cytoreduction.

RESULTS

Forty-two patients were studied by matching 21 patients with endometrioid carcinoma with 21 patients with serous carcinoma. The 5-year survival of the 21 patients with endometrioid carcinoma was 61.9% while the 5-year survival was 71.4% in the patients with serous carcinoma (P=0.22). Of the patients diagnosed with endometrioid carcinoma, the mean survival was 57 months versus a mean survival of 69 months in patients with serous carcinoma (P=0.30). Estrogen receptor levels were not statistically significantly different between the two groups (P=0.108); however, progesterone receptor levels did prove to be statistically significantly different (P<0.001).

CONCLUSIONS

When patients with endometrioid and serous tumours of the ovary are matched for age, grade, stage and level of cytoreduction, there is no difference in either 5-year survival or length of survival.