New daily persistent headache (NDPH) is one of the important headache entities under the category of chronic daily headache. This is the group of primary headache disorders that also includes chronic migraine, chronic tension-type headache, and hemicrania continua. Only recently has NDPH been recognized as a distinct entity by headache specialists.
New daily persistent headache is unique in that the headache is daily from onset, typically in a patient with no prior history. It can continue for years without any sign of alleviation despite aggressive treatment. The headache will start one day and in many instances continue as daily and unremitting pain.
There may be two subtypes of NDPH, a self-limited form which typically goes away within several months without any treatment, and a refractory form, which is resistant to aggressive treatment schemes.
A characteristic and unique feature of NDPH is that most patients are able to pinpoint the exact date when their headaches started. Headache onset may occur in relationship to an infection or flu-like illness (e.g., mononucleosis), surgery (e.g., hysterectomy), or a stressful life event. NDPH is 2.5 times more likely to occur in women than men. Average pain intensity is moderate in most people, though some individuals experience severe pain all of the time.
In order to meet the diagnostic criteria for NDPH, daily pain must be present for more than two months with untreated headache duration greater than four hours a day. Headache location is typically bilateral, and pain can occur anywhere in the head. Pain is usually throbbing or pressing in quality, with associated symptoms such as nausea, light sensitivity, sound sensitivity, or lightheadedness occurring in more than half of individuals. Routine physical activity, such as walking upstairs, may aggravate pain.
In order to arrive at the diagnosis of NDPH, it is necessary to rule out other conditions which can mimic this disorder. The two disorders that are closely similar in presentation include spontaneous cerebrospinal fluid leak and cerebral venous thrombosis. Special testing is required to assess for these conditions.
NDPH can continue for years and even decades after onset and be extremely disabling to the individual. Primary NDPH is considered one of the most difficult headaches to treat. Some NDPH patients do not improve despite aggressive treatment. However, in the first ever published study, Dr. Rozen of MHNI, a recognized authority in NDPH, has shown that five cases of NDPH were successfully treated with varying dosages of gabapentin or topiramate--two drugs in the neuromodulator group of treatments. We are currently looking at other possible correlations and physiological abnormalities that may account for NDPH, thus leading to new and effective therapies.