Persistent Headache

Persistent Headache: Understanding New Daily Persistent Headache (NDPH)

Introduction to New Daily Persistent Headache (NDPH)

New Daily Persistent Headache (NDPH) is a rare and challenging type of chronic daily headache that begins suddenly and persists without remission. It is characterized by the onset of daily and unremitting headaches within three days of onset, lasting four hours or more daily. NDPH is often considered a primary headache disorder, but accumulating evidence suggests it may be a heterogeneous syndrome with various specific triggers.

Epidemiology and Clinical Features

NDPH is relatively rare, with a prevalence estimated between 0.03% to 0.1% in the general population, and it is more common in children and adolescents than in adults. Patients with NDPH can often pinpoint the exact date their headache started, and the pain is constant, sometimes exhibiting migraine features such as nausea, photophobia, and phonophobia . The headache is generalized in most cases but can be unilateral in about 11% of patients.

Potential Triggers and Pathophysiology

Several potential triggers have been identified for NDPH, including infections (such as flu-like illnesses), stressful life events, and extracranial surgeries . In children, infections and minor head injuries are common triggers, with a significant number showing positive Epstein-Barr virus serology at the onset of symptoms. The exact pathogenic mechanism remains unknown, but pro-inflammatory cytokines and cervicogenic problems might play a role.

Diagnosis and Subtypes

The diagnosis of NDPH is primarily clinical, based on a typical history, and requires the exclusion of secondary causes through proper laboratory investigations. According to the International Classification of Headache Disorders (ICHD-2), NDPH is classified as a primary headache if migraine features are absent. However, a revised definition (NDPH-R) that includes patients with migraine features has been proposed to create a more homogeneous group for study and treatment.

Treatment Challenges and Options

NDPH is one of the most treatment-refractory primary headache disorders, with very few effective treatment options available . Common prophylactic drugs used for chronic migraine or tension-type headaches are often employed, but their effectiveness is limited. Some patients may benefit from treatments such as ketamine infusion, onabotulinum toxin type A, intravenous lidocaine, intravenous methylprednisolone, and nerve blockade, although these are usually ineffective for many.

Prognosis and Future Research

The prognosis for NDPH is generally poor, with most patients experiencing persistent headaches. However, about 15% of patients may remit, and 8% may have a relapsing-remitting type. Further research is needed to better understand the underlying pathogenesis and to develop effective treatment strategies. Multi-center randomized controlled trials are recommended to establish evidence-based treatments for this burdensome disorder .

Conclusion

New Daily Persistent Headache is a complex and enigmatic disorder that significantly impacts the quality of life of those affected. While various potential triggers and treatment options have been identified, much remains unknown about its pathophysiology and effective management. Continued research and clinical trials are essential to improve our understanding and treatment of NDPH, offering hope for better outcomes for patients in the future.

Summary

Not a yes or no question