Are infrequent episodic, frequent episodic and chronic tension-type headache inherited? A population-based study of 11 199 twin pairs

The objective was to investigate the importance of genetic and environmental factors for infrequent episodic, frequent episodic and chronic tension-type headache. Twin pairs recruited from the population-based Danish Twin Registry received a posted questionnaire. Only twin pairs where both twins replied were included. A total of 3523 monozygotic (MZ), 4150… CONTINUE READING