Increased water intake to reduce headache: learning from a critical appraisal

Water intake is a cost effective, non-invasive and low-risk intervention to reduce or prevent headache pain.

Chronic mild dehydration may trigger headache. Increased water intake could help. A small trial shows modest benefit; however, a larger methodologically sound randomized controlled trial is needed to confirm efficacy.

Spigt, M., Weerkamp, N., Troost, J., van Schayck, C. P., & Knottnerus, J. A. (2012). 'A randomized trial on the effects of regular water intake in patients with recurrent headaches.' Family practice, 29(4), 370-5. Doi: 10.1093/fampra/cmr112 CLINICAL SCENARIO: Patients from primary care registered as 'headache', 'tension headache' and/or 'migraine' for more than one year who suffer at least two episodes of moderately intense headache or more than four mildly intense episodes of headache per month with a daily fluid intake of less than 2.5 litres per day.

Patient/Problem = Headache > 1 year with 2 moderately intense or 4 mildly intense episodes per month Intervention = 1.5 litres water per day + stress control and sleep hygiene Comparison/Control = stress control and sleep hygiene Outcome = Reduce or eliminate headache Methodology = Therapy RCT Table 1: Final Search Terms TRIP Data Base: hits = 517 used filter Extended Primary research 4 found 1 paper applicable 'Water intake '[MeSH Terms] AND 'Headache '[All Fields]' Best match to PICO, (2012) RCT SELECTION CRITERION AND OVERALL RESULTS: 102 headache patients in16 primary care clinics were randomized into control (n = 50) and intervention groups (n = 52) Inclusion criteria = two > episodes of moderately intense headache or five > mildly intense headaches per month and total fluid intake > 2.5 litres per day, Follow-up @ 3 months. 79% intervention and 66% of controls completed RCT. Drinking more water resulted in a statistically significant improvement of 4.5 (confidence interval: 1.3-7.8) points on Migraine-Specific Quality of Life (MSQOL). 47% in the intervention (water) group self-reported improvement (6 > on a 10-point scale) against 25% in controls. Drinking water did not reduce headache days.

The transparency from the author of this critically appraised paper enables others to use this study as a teaching tool and to learn from the shortcomings in the trial. The study was underpowered and contains methodological shortcomings. Participants were partially un-blinded during the trial increasing the risk for bias. Only the subjective measures are statistically significant and attrition was significant. The intervention is low risk and of negligible cost. A methodologically sound RCT is recommended to evaluate if the intervention has beneficial effects.