Bone mineral density changes in diabetic patients : a prospective study

الملخص EN

Background: Osteoporosis is being defined conceptually, as well as operationally only over the last ten years.

Osteoporosis is described as a systemic skeletal disease characterized by low bone mass and microarchitectural deterioration of bone tissue with a consequent increase in bone fragility and susceptibility to fractures.

The clinical use of DEXA for the diagnosis of osteoporosis is usually based on the comparison of values obtained with those from a healthy age and sex matched population with a standard curve for normal values.

There is still controversy about the levels of BMD and the risks of osteoporosis in Type 1 and Type 2 Diabetes.

Most, but not all studies have reported low BMD values in Type 1 diabetes.

It is not yet known whether the low BMD values in Type 1 diabetic patients result from reduced peak bone mass or increased bone loss.

Aim of study: To assess the effect of Type 1 and Type 2 diabetes mellitus in patients with onset of either types of diabetes after 30 years of age and all of whom were treated with insulin.

We also aimed to evaluate the role of insulin treatment on BMD in diabetic patients.

Methodology: Eighty diabetic patients were included in the study, 39 males and 41 females.

All cases were subjected to thorough history taking and clinical examination.

Inclusion criteria included age group between 45 and 64 years and onset of both types of diabetes > 30 years of age.

Type 1 and Type 2 diabetes were distinguished by measurement of plasma C peptide 6 minutes after glucagon stimulation.

Candidates were subjected to calculation of body mass index (BMI) {weight (kg)/ height (M2)}.

BMD (g/cm2) was measured in the proximal femur (neck and trochanteric region) using DEXA.

Results: BMI was higher in Type 2 diabetic women and lower in Type 1 diabetic women.

On the other hand, Type 1 diabetic men had lower BMI than men in Type 2 diabetic and control groups.

The lower BMD values in type 1 diabetic men compared to type two diabetic and control men showed no significant differences.

At both the femoral neck and trochanteric region, BMD values in Type 1 diabetic men were significantly lower than in Type 2 diabetic and the control men, however the values in the last two groups showed no significant changes after adjustment for age and BMI.

In addition, the differences between Type 1 diabetic and control men remained unchanged after adjustment for age, BMI and calcium intake.

Type 1 diabetic women had significantly lower BMD values than in Type 2 diabetic and control women.

After adjustment for age and BMI, the significant differences between Type 1 diabetic and the control women remained unchanged but it was lost when compared to Type 2 diabetic women.

Conclusion: In conclusion, this study shows that Type 1 diabetic patients have significantly lower BMD values than Type 2 diabetic patients or non-diabetic control subjects.

Being the exact mechanisms of this lower BMD values in Type 1 diabetes are not clear, these patients should be well evaluated for known determinants of osteoporosis and offered all appropriate measures to prevent and treat osteoporosis with the ultimate goal of preventing fractures.