ABSTRACT
OBJECTIVE: Increased levels of depressive symptoms, fatigue or pain (all dimensions of reduced health-related quality of life (HRQOL)) are common in people with type 2 diabetes mellitus (DM). Earlier studies have reported associations between low vitamin D status and fatigue and depressive symptoms. The aim of the present study was to examine the effects of vitamin D supplementation on dimensions of HRQOL in people with type 2 DM. DESIGN: Randomised, double-blind, placebo-controlled trial. METHODS: The effect of monthly cholecalciferol 50,000 IU vs placebo on HRQOL was assessed in 275 adults with type 2 DM derived from general practices. HRQOL at baseline and after six months using the Short Form 36 Health Survey (SF-36) was collected. Linear regression analyses were used to compare the change in HRQOL over time between the vitamin D and placebo group. RESULTS: 187/275 (68%) completed baseline and follow-up SF-36 and were included in the analysis. Median serum 25-hydroxyvitamin D almost doubled in the intervention group compared to that in the placebo group (58.5-106.0 nmol/L vs 60.0-61.5 nmol/L, respectively). A small significant difference (adjusted B: -8.90; 95% CI: -17.16 to -0.65) between both groups was seen concerning the SF-36 domain role limitations due to physical problems in disadvantage of the vitamin D group. CONCLUSIONS: Six months of vitamin D supplementation did not improve HRQOL in non-vitamin D-deficient people with type 2 DM managed on oral antidiabetic therapy.
ABSTRACT
AIMS: To test whether vitamin D status was associated with health-related quality of life in people with Type 2 diabetes mellitus. METHODS: Demographic and clinical characteristics, including health-related quality of life scores, were obtained from 241 adult patients with Type 2 diabetes managed with oral hypoglycaemic agents. Health-related quality of life was assessed using the Short-Form 36 Health Survey. Multiple logistic regression analysis was used to investigate the association between vitamin D status and health-related quality of life, with adjustment for confounders. RESULTS: The mean age of the patients included in the study was 67 ± 8 years. Their mean HbA1c concentration was 52 ± 8 mmol/mol (6.9 ± 0.7%) and their mean serum 25-hydroxyvitamin D concentration was 59 ± 23 nmol/l. Vitamin D deficiency (serum 25-hydroxyvitamin D < 50 nmol/l) was present in 38% of patients. No significant associations were found between vitamin D status and health-related quality of life. CONCLUSIONS: Vitamin D status was not associated with health-related quality of life in patients with Type 2 diabetes. This could be explained by the relatively high serum 25-hydroxyvitamin D concentration, good glycaemic control and relatively good health-related quality of life of all patients. A prospective study among patients with vitamin D deficiency and poor glycaemic control would be interesting for future research.
