Italian Trigeminal Autonomic Cephalalgias Assessment Study

Italian Trigeminal Autonomic Cephalalgias Assessment Study (ITACA)

ITACA is a prospective, multicenter, observational longitudinal cohort study conducted in routine clinical practice at six Italian headache centers. Approximately 800 adults with trigeminal autonomic cephalalgias (cluster headache, paroxysmal hemicrania, SUNCT, SUNA, or hemicrania continua) diagnosed according to ICHD-3 will be enrolled. The study will describe clinical features and real-world treatment patterns and will evaluate treatment effectiveness and tolerability, changes in clinical features over time, comorbidities, lifestyle factors, patient-reported outcomes, and predictors of treatment response and disease progression. No investigational intervention will be assigned; treatments are prescribed by treating physicians as part of routine clinical care. Participants will be assessed at baseline and during routine follow-up visits, approximately every 3-6 months or as clinically indicated, for up to 3 years. Relevant clinical data already available in medical records before enrollment may also be collected to improve baseline characterization and reconstruction of disease course.

Trigeminal autonomic cephalalgias are rare and highly disabling primary headache disorders characterized by unilateral pain and ipsilateral cranial autonomic symptoms. Their clinical heterogeneity, frequent misdiagnosis, diagnostic delay, and the limited availability of large longitudinal datasets make accurate phenotypic characterization and evidence-based treatment selection difficult. ITACA is designed to address these gaps through systematic real-world data collection in a multicenter setting.

The study is a prospective, multicenter, observational longitudinal cohort conducted in routine outpatient clinical practice. Recruitment is planned for 3 years, with follow-up for up to 3 years per participant and an overall study duration of approximately 6 years. Consecutive eligible adult outpatients with a diagnosis of cluster headache, paroxysmal hemicrania, SUNCT, SUNA, or hemicrania continua according to ICHD-3 will be invited to participate. Relevant pre-enrollment clinical information already available in medical records may be collected retrospectively at baseline to improve characterization of disease history.

No protocol-mandated treatment or investigational intervention is assigned. Acute and preventive treatments are prescribed independently by treating physicians according to routine clinical practice. Data are collected at baseline and at routine follow-up visits, expected approximately every 3-6 months or whenever clinically indicated. Collected information includes attack frequency, duration and severity, cranial autonomic and other accompanying symptoms, temporal patterns, disease course, treatment history and ongoing treatment exposure, treatment effectiveness and tolerability, adverse events, comorbidities, lifestyle factors, concomitant medications, headache diary information, and patient-reported measures. Questionnaires may include PGIC, ASC-12, EQ-5D, SF-36, CHIQ, HARS, HDRS, HADS, LDQ, and PSQI according to routine practice and local availability. Data are recorded in a standardized electronic case report form using REDCap.

The planned sample size is approximately 800 participants, expected to include about 70-80% with cluster headache and 20-30% with other trigeminal autonomic cephalalgias. Analyses will be primarily descriptive and will include longitudinal and multivariable models to assess clinical characteristics, treatment outcomes, and predictors of response, refractoriness, and disease progression.

Inclusion Criteria:

• Age 18 years or older.
• Diagnosis of trigeminal autonomic cephalalgia (cluster headache, paroxysmal hemicrania, SUNCT, SUNA, or hemicrania continua) according to ICHD-3 criteria.
• Ability to provide written informed consent.
• Availability for longitudinal follow-up and data collection.

Exclusion Criteria:

• Secondary headache disorders.
• Uncertain or unconfirmed diagnosis of a trigeminal autonomic cephalalgia.
• Severe cognitive impairment or psychiatric condition interfering with reliable data collection.
• Any condition that, in the investigator's judgment, may compromise participation or follow-up.