P151
Prevalent Native Vitamin D levels within a Northern Irish Chronic Kidney Disease Population
McKee J, Hutchinson N, Bradley L, McManus M, Cunningham R, Mullan R, Quinn M, Harron C.
Renal Unit, Antrim Area Hospital, Northern Ireland.
Background Native vitamin D deficiency is higher in Chronic Kidney Disease (CKD) cohorts
than in the general population and is associated with an increased risk of renal disease
progression and death in pre-dialysis patients and for early mortality in haemodialysis patients.
This pilot study was undertaken to identify baseline levels of 25-OH D3 in Northern Irish
patients with CKD stages 3-5 including patients receiving different modalities of renal
replacement therapy.
Methods Wintertime Vitamin D levels were analysed from consented patients attending the
Renal Medicine service. Standardised food frequency questionnaires were completed to
analyse dietary vitamin D intake. Aetiology of CKD, comorbidities, stage of CKD, dialysis
modality if relevant and medications were collated from medical case note review and
electronic records. Results were analysed using PSPP statistical analysis package using
independent t-tests and Pearson correlations.
Results 137 patients (86 male, 68 female) including those attending general nephrology, low
clearance, home therapies and renal transplant clinics and for maintenance haemodialysis
were studies. Mean patient age was 60 years.
Overall, the mean serum 25-OH D was 39.4nmol/L (>72.5nmol/l). Only 9% patients had
replete vitamin D levels. When analysed by CKD stage, all patient groups showed high
proportions of native vitamin D deficiency or insufficiency (see table below). This finding was
particularly marked for the Home Therapies and Transplant patients. Vitamin D level did not
correlate with stage of CKD but did correlate with recorded cardiovascular co-morbidity.
Patient Group
% Deficiency
(patient no.)
% Insufficiency
% Replete
Total Number
Total
General
Low
nephrology: Clearance:
Stage 3
Stage 4/5
Renal Replacement Therapy
HD
74 (101)
60 (24)
79 (22)
73 (22)
Home
Therapies
100 (11)
18 (24)
9 (12)
137
22.5 (9)
17.5 (7)
40
14 (4)
7 (2)
28
23 (7)
3 (1)
30
0
0
11
Transplant
14 (4)
7 (2)
28
79 (22)
Analysis of food frequency questionnaires found that mean daily dietary vitamin D intake was
0.23micrograms (recommended daily intake for adults >65 is 10 micrograms). Estimated
dietary vitamin D intake correlated with serum vitamin D levels in the low clearance and home
therapy groups.
Conclusion This study has quantified and emphasized the degree of 25-OH D deficiency in our
Northern Irish CKD population. It has also highlighted the possibility of using targeted dietary
and lifestyle advice to improve dietary vitamin D intake.