Summary We assume that 25(OH)D level >50 nmol/l is
necessary for adequate parathyroid hormone (PTH) suppression
in our population. The epidemiology of vitamin D
status in Bulgarian population shows deficiency in 21.3 %,
insufficiency in 54.5 % and sufficiency in 24.2 %. The mean
level of 25(??)D for the Bulgarian population is
38.75 nmol/l (95 % CI, 38.00–39.49).
Purpose The aim of the present study was to investigate the
vitamin D levels in Bulgaria and the prevalence of vitamin
D deficiency depending on gender and age, as well as to
define population-specific 25(OH)D sufficiency thresholds
through the relationship with PTH.
Material and method This cross-sectional study was
conducted in January–February 2012 and included 2,032
subjects in 12 regions—1,076 women (53 %) and 956
men (47 %), mean age 49.30±14.75 years (20–80 years),
divided into three age groups: young (20–44 years, n=894),
middle-aged (45–59 years, n=534), and elderly (=60 years,
n=604). 25(OH)D and PTH were measured in all subjects.
Results The mean level of 25(??)D was 38.75 nmol/l
(95 % CI, 38.00–39.49). The men had significantly higher
25(??)D levels in comparison to women (41.51 nmol/l
(95 % CI, 40.45–42.56) vs.36.29 nmol/l (95 % CI, 35.27–
37.32), p<0.05). We did not find significant differences in
the 25(??)D levels between the three age groups. The prevalence
of vitamin D deficiency was 21.3 %; insufficiency,
54.5 %; and sufficiency, 24.2 %. Deficiency was more prevalent
in women (26.9 %) than in men (15.1 %), p<0.001. PTH
started to rise over the upper limit of the reference range at
mean 25(OH)D 50 nmol/l. We assume that levels over
50 nmol/l are necessary for adequate PTH suppression.
Conclusions The status of vitamin D in our country is worrisome,
and it is largely underestimated. The defining of a
vitamin D sufficiency levels may help the devising of adequate
strategies for prevention and treatment in clinical practice.