New research published in Headache suggests there is a relationship between serum vitamin D levels and chronic tension-type headaches (CTTH).
Sanjay Prakash, DM, from the Department of Neurology at the Smt B. K. Shah Medical Institute and Research Center in Gujarat, India, and colleagues examined the association between CTTH and serum 25-hydroxy vitamin (25(OH) D) levels in 100 patients (aged 18 years or older) with CTTH and 100 matched healthy control patients.
The researchers found that serum 25(OH) D levels were significantly lower in patients with CTTH compared with control patients (14.7 vs 27.4 ng/mL). Vitamin D deficiency [serum 25 (OH) D <20 ng/mL] was also greater in patients with CTTH (71%) compared with in control patients (25%).
Patients with CTTH also had a significantly higher prevalence of musculoskeletal pain (79% vs 57%), and muscle weakness (29% vs 10%) and a higher muscle tenderness score (7.5 vs 1.9) and bone tenderness score (3.0 vs 0.8) compared with control patients. Those with CTTH who were vitamin D deficient had a greater prevalence of musculoskeletal pain in the lower back (58% vs 31%) and muscle weakness in the neck muscles (38% vs 7%), higher muscle and bone tenderness scores, greater prevalence of associated fatigue (44% vs 17%), and a more prolonged course (15.5 months vs 11.2 months).
There was a strong positive correlation between serum vitamin D levels and total muscle tenderness score (R2=0.7365) and total bone tenderness score (R2=0.6293), as well.
Although these findings and findings from previous studies lend evidence to the possibility that vitamin D deficiency affects musculoskeletal pain, muscle weakness, and muscle atrophy, it is difficult to find a causal association with a cross-sectional study.
Limited physical activity may be an underlying cause for both muscle atrophy and low vitamin D levels. Vitamin D deficiency also closely mimics CTTH and is common in the general population, so it is possible that both conditions may be comorbid in the same patient and may produce overlapping clinical features.
“However, identifying even this comorbid condition may be important for therapeutic purposes,” the researchers noted.
“Intervention studies are required to find out if supplementation of vitamin D is effective in patients with CTTH.”
- The study sample was collected from convenient samples from a neurology clinic. These participants from a clinical setting may represent a more severe population of CTTH and may also not be generalizable.
- This was a single-center study.
- The possibility that some patients in the study had migraine cannot be ruled out.
- Some possible confounders, such as alcohol intake, sun exposure duration, fatigue, and depression, were not included in the study.
- ELISA assay has some limitations, so these results should be confirmed with mass spectrometry.
Prakash S, Rathore C, Makwana P, Dave A, Joshi H, Parekh H. Vitamin D deficiency in patients with chronic tension-type headache: a case-control study [published online May 3, 2017]. Headache. doi: 10.1111/head.13096