Hypocalcemia and vitamin D deficiency amongst migraine patients: a nationwide retrospective study

Background and Objectives
Inadequate vitamin D and calcium intake have been linked to many health issues including chronic headaches. Some studies suggested an association between low vitamin D levels and an increased risk of frequent headaches in middle-aged and older men; however, no single study reported the role of these deficiencies in migraine patients. We aimed to investigate the association of hypocalcemia and vitamin D deficiency with migraine hospitalizations.

Materials and Methods
A population-based retrospective cross-sectional analysis of the Nationwide Inpatient Sample (NIS) (years 2003–2014) in migraine hospitalizations was performed. The prevalence, demographic characteristics and All Patient Refined Diagnosis Related Groups severity/disability association were compared in patients with hypocalcemia and vitamin D deficiency to those without deficiencies, using ICD-9-CM codes. Weighted analyses using Chi-Square, paired Student’s t-test, and Cochran–Armitage trend test were performed. Survey logistic regression was performed to find an association between deficiencies and migraine hospitalizations and deficiency induced disability amongst migraineurs.

Between years 2003 and 2014, of the total 446,446 migraine hospitalizations, 1226 (0.27%) and 2582 (0.58%) presented with hypocalcemia and vitamin D deficiency, respectively. In multivariable analysis, hypocalcemia [Odds Ratio (OR): 6.19; Confidence Interval (CI): 4.40–8.70; p < 0.0001] and vitamin D deficiency (OR: 3.12; CI: 2.38–4.08; p < 0.0001) were associated with markedly elevated odds of major/extreme loss of function. There was higher prevalence (3.0% vs. 1.5% vs. 1.6%; p < 0.0001) and higher odds of migraine among vitamin D deficiency (OR: 1.97; CI: 1.89–2.05; p < 0.0001) patients in comparison to patients with hypocalcemia (OR: 1.11; CI: 1.03–1.20; p = 0.0061) and no-deficiency, respectively.

In this study, we demonstrated a significant association between hypocalcemia and vitamin D deficiency with migraine attacks and deficiency-induced loss of function among migraineurs. Early preventive measures may reduce the disability in migraineurs