Bone mineral density in young Chilean patients with type 1 diabetes mellitus

In this study, our aim was to analyze bone mineral density (BMD) in patients with type 1 diabetes mellitus (T1DM) and compare them with a healthy reference population; in addition, we aimed to observe the association between BMD and the following variables: age at onset, disease duration, metabolic control, pubertal stage, level of physical activity, clinical parameters and nutrient intake.A total of 30 patients with T1DM were included in the study. BMD was determined using dual-energy X-ray densitometry (DXA). Participants with a z-score of values ≥-1 were accepted as normal; BMDs between -2 and -1 were defined as being in the low range of normality; ≤-2 were defined as having low BMD. The 25-hydroxy vitamin D level was classified as sufficient (30-100 ng/mL), insufficient (20-30 ng/mL), and deficient (<20 ng/mL).The percentages of patients with deficient and insufficient 25(OH) vitamin D levels were 50% and 45.8%, respectively. Lumbar spine (LS2-LS4) BMD, total body (TB) BMD and femoral neck (FN) BMD were found in the normal range for more than 80% of the subjects, with no significant differences due to gender. No strong correlations between clinical variables, biochemical parameters and nutrient intake were observed; however, a moderate positive correlation was found between serum calcium and LS2-LS4 BMD (p<0.05). Regression analysis showed that serum calcium, duration of diabetes and intake of sodium and protein are significant factors in determining LS2-LS4 BMD and TB BMD.Patients with T1DM had a normal mean BMD at all sites evaluated, except for two patients who had low BMD at the lumbar spine. More than 95% of patients had insufficient or deficient vitamin D levels. With respect to all the variables studied, serum calcium presented the highest significant correlation with LS2-LS4 BMD.