Dr. Subashri Mohanasundaram
Department of Nephrology
Government Thoothukudi Medical College & Hospital, India
In 1972, Bana et al, first described dialysis-related headaches, which typically occur a few hours after beginning dialysis in patients without a past history of headaches or of distinctly different quality on comparison with previously experienced headaches. These headaches are described as being mild in quality, bifrontal to start with, and they often worsen in the reclining position into a severe throbbing headache. Sometimes, dialysis-related headaches may be accompanied with nausea and vomiting. From various studies, the prevalence of dialysis-related headache varies between 27% and 73%.
Diagnostic criteria: According to the 2013 diagnostic criteria presented in the International Classification of Headache Disorders-3 beta, dialysis-related headache presents the following characteristics:
A. At least three episodes of acute headache fulfilling the criteria C & D
B. The patient is undergoing hemodialysis
C. Evidence of causation is shown through at least two of the following:
- Each headache episode starts during hemodialysis
- One or both of the following:
- Each headache episode worsens during hemodialysis
- Each headache attack resolves within 72 hours after completion of hemodialysis
- The headache episodes disappear after a successful kidney transplant and the end of hemodialysis
D. The headache cannot be better classified by other ICHD-3 criteria
Pathophysiology: The pathophysiology of dialysis-related headache has not been completely elucidated. However certain factors seem to be associated with it, like sudden alterations of blood pressure, low levels of blood of magnesium, high calcium or magnesium in dialysate fluid, etc.
- Caffeine withdrawal (removed by dialysis)
- Acetate dialysate
- Intradialytic hypertension / hypotension
- Hard water syndrome [high levels of calcium/ magnesium in dialysate: The maximum allowable levels and are as follows: calcium ≤2 mg/L, magnesium ≤4 mg/L(according to AAMI standards)]
- Fluoride/chloramine intoxication (in dialysate)
In addition, acute yet transient alteration in serotonin levels, cerebral vasoconstriction, hypoxemia, or renin-angiotensin-aldosterone disturbances that contribute to headache. For example, patients on dialysis with hypertension who have sudden drop in blood pressure can activate their renin-angiotensin system causing vasoconstriction in order to increase their blood pressure.
There is a paucity of data on how to treat dialysis-related headaches. The following medications can be tried in the treatment.
- Caffeine: Patients, who consume more than 200 mg of caffeine per day for more than 2 weeks, may experience bilateral and/or pulsatile headache within 24 hours after last caffeine intake. In these patients, on administration of 100 mg caffeine, the headache disappears within 1 hour.
- Amitriptyline /chlorpromazine
- Angiotensin-converting enzyme inhibitors (isolated case report)
- Magnesium replacement (in patients who have hypomagnesemia)
- Onabotulinum toxin (only FDA approved drug in treatment for prevention of chronic migraine, though not tested in dialysis patients with chronic daily headache)
- Bicarbonate dialysate
- Slow dialysis with reduced blood flow rate
- Sodium profile & Ultrafiltration profile, to prevent sudden alterations in serum sodium and blood pressure levels
- Caffeine ingestion during hemodialysis, in habitual caffeine consumers
Despite the high prevalence of headache in the dialysis population, there is a paucity of research surrounding its pathophysiology and treatment.
Reviewed by Matthew A. Sparks