Possible association between vitamin D deficiency and restless legs syndrome

Figures & data

Table 1 Comparisons of demographical and clinical factors among the VDD and VDN groups

	VDD (n=119)	VDN (n=36)	Statistics
Age (years)	48.80±11.44	51.03±12.31	t=1.01, P=0.31
Sex
Male	9 (7.6%)	6 (16.7%)	χ^2=2.62, P=0.10
Female	110 (92.4%)	30 (83.3%)
RLS
Present	60 (50.4%)	6 (16.7%)	χ^2=12.87, P<0.001*
Absent	59 (49.6%)	30 (83.3%)
Vitamin D (ng/mL)	11.19±4.73	37.19±9.97	t=21.59, P<0.001*
Calcium (mg/dL)	10.30±2.39	9.52±0.44	t=−0.55, P=0.58
Phosphate (mg/dL)	3.27±0.44	3.61±0.52	t=3.79, P<0.001*
ALP (IU/L)	82.84±18.79	76.52±18.80	t=−1.76, P=0.08
Ferritin (ng/mL)	42.51±23.58	51.77±27.44	t=1.96, P=0.051
BMI (kg/m^2)	26.19±2.83	25.57±2.18	t=1.01, P=0.23
Upper extremity involvement
Present	10 (8.2%)	2 (33.3%)
Absent	50 (81.8%)	4 (66.6%)
IRLS score	23.54±4.25	21.50±3.72

Notes: Values are expressed as mean ± SD. A P-value <0.05 was considered statistically significant.

* Significant P-value.

Abbreviations: ALP, alkaline phosphatase; BMI, body mass index; IRLS, International Restless Legs Syndrome rating scale; RLS, restless legs syndrome; SD, standard deviation; VDD, vitamin D deficiency; VDN, normal vitamin D.

Table 2 The logistic regression analysis of variables associated with RLS

Variable	OR	P	Cl
Age (years)	1.003	0.84	0.973–1.034
Sex	0.884	0.86	0.225–3.465
Presence of vitamin D deficiency	5.085	<0.001**	1.972–13.113
Vitamin D (ng/mL)	1.047	0.006**	1.014–1.082
Calcium (mg/dL)	1.139	0.78	0.455–2.846
Phosphate (mg/dL)	1.271	0.53	0.600–2.692
ALP (IU/L)	1.009	0.40	0.988–1.029
Ferritin (ng/mL)	0.998	0.80	0.983–1.013
BMI (kg/m^2)	0.528	0.85	0.845–1.090

Notes: A P-value <0.05 was considered statistically significant.

** Significant P-value.

Abbreviations: ALP, alkaline phosphatase; BMI, body mass index; CI, confidence interval; OR, odds ratio; RLS, restless leg syndrome.