Introduction: Vitamin D has a potentially beneficial role in insulin resistance, but there is a lack of evidence in elderly. We report preliminary results of an ongoing study that investigated the effect vitamin D replacement treatment (12 weeks) on insulin resistance and metabolic parameters in elderly people with normal glucose tolerance.
Methods/design: The studys eligibility criteria were body mass index <30.0 kg/m2, creatinine levels <1.2 mg/dl, no evidence of prediabetes and diabetes, no self-reported use of hypoglycemic drugs, and fasting serum glucose <100 mg/dl. Eighty-six participants (aged≥65 years) were eligible for the present investigation. Serum concentrations of 25(OH) D were categorized as deficient (group I, <20 ng/ml), insufficient (group II, 20 to 30 ng/ml), or normal (group III, >30 ng/ml) vitamin status, respectively. Group I was treated initially with 300 000 international units (IU) of vitamin D3 ampoule orally once for six weeks, and then 880 IU of vitamin D3 plus 1000 mg of ionized calcium tablet daily thereafter. Group II was treated with 880 IU of vitamin D3 plus 1000 mg of ionized calcium tablet daily. Group III received with 400 IU of vitamin D3 plus 600 mg of ionized calcium tablet as daily supplement.
Results: There were no significant differences in all baseline parameters except vitamin D levels among three groups. After 12 weeks of vitamin D replacement therapy, 95.3% of all subjects had 25(OH) D levels within the normal range with a mean level of 53.4±21.3 ng/ml. There was a significant reduction in HOMA-IR scores in group I (P<0.001), but not in group II (P=0.074) and group III (P=0.123). There were no statistically significant differences in lipid parameters in all groups.
Conclusion: We found that supplementation in vitamin D deficient subjects may modify insulin sensitivity in elderly.
30 Apr - 04 May 2011
European Society of Endocrinology