Vitamin D Levels Among Rheumatoid Arthritis Sudanese Patients: Prevalence and Correlation to Disease Activity – A Bicentric Study

Figures & data

Table 1 Demographic Characteristics of the Participants

Variable		Frequency (%) N = 90
Age (years)*	< 20	2 (2.2)
	21–40	33 (36.9)
	41– 60	44 (48.9)
	> 60	11 (12)
Gender	Male	11 (12.1)
	Female	79 (87.9)
Residence**	Khartoum	69 (76.9)
	Gazira	8 (8.7)
	West	7 (7.8)
	East	3 (3.3)
	North	3 (3.3)
Job	Employed	74 (82.2)
	Students	6 (6.7)
	Unemployed	10 (11.1)

Notes: *Age (years): <20 (youngest being 18 years old). **Residence (Khartoum and Gezira; Central Sudan).

Table 2 Study Population Disease Activity, Treatment Lines and Duration

Variable		Frequency (%) N = 90
Duration of disease activity (year)	< 1	19 (21.1)
	1–4	36 (40)
	5–10	25 (27.8)
	> 10	10 (11.1)
Treatment prescribed	HCQ	81 (90.1)
	Methotrexate	31 (34.4)
	Folic acid	34 (37.7)
	Prednisolone	21 (22.9)
	Azathioprine	3 (3.3)
Duration of Medication (year)	< 1	15 (16.7)
	1–5	67 (74.4)
	> 5	8 (8.9)

Table 3 DAS-28 Score and Vitamin D Level

Vitamin D Level*	DAS-28 Score**			P value
	Low	Moderate	High
Deficient	3	15	8	<0.001^
Insufficient	5	36	12
Sufficient	3	6	2

Notes: *Reference range of Vitamin D: Normal level (30–100ng/mL), Insufficiency (10–30ng/mL) and deficiency (less than 10 ng/mL). **DAS-8 Score: Low (≥2.6 - <3.2), Moderate (≥3.2 - <5.1) and High (≥5.1). ^P-value: <0.001 (95% CI: −0.8591 to 0.0015) and r = −0.44 (statistically significant and moderately strong negative correlation between Vitamin D levels and DAS-28 scores).

Figure 1 Correlation between RA activity – *DAS 28 score and vitamin D level. *P-value: <0.001 (95% CI: −0.8591 to 0.0015) and r= −0.44.