Table 1. Mean vitamin D level according to different factors.

Factor	Mean vitamin D level, nmol/l	N	P value
All	31,97	152
Sex			P = 0.003
Male	34,95	108
Female	24,65	44
Smoke			P = 0.667
Never	33,78	24
Former	32,55	88
Current	29,61	40
DM			P = 0.951
yes	31,89	53
no	32,01	99
MS			P = 0.860
yes	32,11	38
no	31,92	114
Arterial hypertension			P = 0.516
yes	31,40	105
no	33,25	47
mMRC–all grades			P = 0.016
mMRC 0	39,17	14
mMRC 1	36,65	39
mMRC 2	32,13	51
mMRC 3	26,16	47
mMRC 4	14,04	1
mMRC– 0,1 vs ≥2			P = 0.008
mMRC 0 or 1	37,31	53
mMRC ≥2	29,11	99
CAT–all grades			P = 0.109
CAT 0–9	39,86	25
CAT 10–19	31,85	72
CAT 20–29	29,81	43
CAT ≥30	24,01	12
CAT 0–9 vs ≥10			P = 0.061
CAT 0–9	39,86	25
CAT ≥10	30,42	127
FEV1 –GOLD stages			P = 0.055
FEV1 <30%	29,43	16
FEV1 30–50%	25,97	46
FEV1 50–80%	35,58	73
FEV1 >80%	35,09	17
FEV1 - >50% vs <50%			P = 0.004
FEV1 >50%	35,49	90
FEV1<50%	26,86	62