Magnesium and headache after aneurysmal subarachnoid haemorrhage.
BACKGROUND
In patients with aneurysmal subarachnoid haemorrhage (SAH), headache typically is severe and often requires treatment with opioids. Magnesium has analgesic effects in several conditions, but whether it reduces headache after SAH is unknown.


METHODS
In a cohort of 108 SAH patients included in the randomised controlled trial Magnesium in Aneurysmal Subarachnoid Haemorrhage-II (MASH-II), severity of headache was regularly assessed on an 11-point scale until day 10 after SAH. Headache was treated according to a standardised protocol with acetaminophen, codeine, tramadol or piritramide. Serum magnesium levels were assessed every other day. Differences in mean headache scores between patients with mean high (>1.0 mmol/l) and normal (< or =1.0 mmol/l) magnesium levels were analysed with a Student t test. Crude and adjusted ORs for the use of codeine, tramadol and piritramide for patients with high versus normal magnesium levels were calculated with logistic regression.


RESULTS
The 61 patients with high magnesium levels had lower mean headache scores (4.1) than the 47 patients with normal magnesium levels (4.9; mean difference, 0.8; 95% CI 0.1 to 1.6) and required less tramadol (adjusted OR, 0.3; 95% CI 0.1 to 0.7) or piritramide (adjusted OR 0.2; 95% CI 0.1 to 0.5). There were no differences in the use of acetaminophen or codeine.


CONCLUSIONS
In SAH patients, elevated serum magnesium levels are associated with slightly less severe headache and less frequent use of opioids. These data imply that intravenous magnesium therapy, besides a supposed beneficial effect on outcome, also provides pain relief for SAH patients, for whom it might also improve functional outcome.
Dorhout Mees
S M
SM
Department of Neurology, Room G03.228, University Medical Center Utrecht, PO Box 85500, 3508 GA, Utrecht, The Netherlands. s.m.dorhoutmees@umcutrecht.nl
Bertens
D
D
van der Worp
H B
HB
Rinkel
G J E
GJ
van den Bergh
W M
WM
D000700:Analgesics / Q000008:administration & dosage / Q000627:therapeutic use*; D000701:Analgesics, Opioid / Q000627:therapeutic use; D003061:Codeine / Q000627:therapeutic use; D005260:Female; D006261:Headache / Q000188:drug therapy* / Q000209:etiology*; D006801:Humans; D007275:Injections, Intravenous; D016015:Logistic Models; D008278:Magnesium Sulfate / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010892:Pirinitramide / Q000627:therapeutic use; D020521:Stroke / Q000150:complications / Q000209:etiology; D013345:Subarachnoid Hemorrhage / Q000150:complications*; D014147:Tramadol / Q000627:therapeutic use
D000700:Analgesics; D000701:Analgesics, Opioid; D014147:Tramadol; D010892:Pirinitramide; D008278:Magnesium Sulfate; D003061:Codeine