New daily persistent headache (NDPH) is characterized by daily, persistent headache with clearly remembered onset, preceding events or triggers and treatment refractoriness of headache. The pathophysiology of NDPH is still unresolved. NDPH has been associated with somatoform disorder (DSM 4 TR). Somatization is characterized by vivid memory, disproportionate and persistent thought about symptoms that may explain many characteristics of NDPH. However, tendency towards somatization has not been studied in NDPH patients.
In this cross-sectional study, we evaluated somatization in NDPH, chronic migraine (CM), and chronic tension type headache (CTTH) by comparing the prevalence of somatic symptom disorder (SSD, DSM-5). We evaluated the past tendencies to somatization by comparing various characteristics of past somatic symptoms (number, duration, type, clearly remembered onset, etc.) between NDPH, CM, and CTTH.
Forty-seven patients each of NDPH and CTTH and 46 patients of CM were evaluated. Criteria for SSD was fulfilled by 85.1% of NDPH and CTTH patients and only 45.7% of CM. Past history of somatic symptoms was seen in 70% patients with NDPH, 15.2% CM, and 23.4% CTTH (p<0.001). Median number of past somatic symptoms was higher in NDPH. All NDPH patients clearly remembered the onset of at least one past somatic symptom. None of CM and CTTH patients remembered the onset of past somatic symptoms.
NDPH patients displayed significant past history of somatization. Continuation of past tendencies to manifest as NDPH suggests that NDPH may be an epiphenomenon of somatization.

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