Discussion:
Growing burden of diabetes is a major concern in Indian population. With an alarming increase in diabetes cases India will be labelled as diabetes hub of the world. With the changing trend in lifestyle vis -a vis lack of physical exercise , sedentary life style, urbanisation, advancing age, dietary habits etc will result in increasing incidence of DM. A large portion of health care expenditure by the patients effect the health care infra structure because of financial burden.(20) In India it is largely the private sector which spends approximately 68% of financial cost for delivering health care services for diseases in both rural and urban population.(21).Type 2 DM accounts for around more than 90% of all diabetes. This type includes individuals who have relative insulin deficiency and peripheral insulin resistance. Sometimes initially and lately throughout their life time they become dependent on insulin therapy to survive. There are many etiologies of type 2 DM, although the specific ones are unknown. Most of the patients with type 2 DM are obese or overweight. Type 2 DM is mostly missed on diagnosis for many years because symptoms develop gradually and are not severe enough initially and go unnoticed by the patient. Even though not severe in the beginning micro and macrovascular complications do start commencing from the initial stages of disease. Diabetic ketoacidosis ,one of the serious complications rarely occurs in association with stress, like infection or with some drugs like steroids, antipsychotics etc.(22,23)
In our study vitamin D levels were low in diabetic mellitus group when compared to control group. There are many studies which relate occurrence of diabetes mellitus type 2 with vitamin D deficiency.(24-31).As postulated by meta-analysis done by Pittas et al. suggest that binding of vitamin D to beta cell receptors facilitated by calcium causes regulation of insulin secretion.(32).Thus deficiency of vitamin D can cause impaired insulin secretion in patients with type 2 DM. Vitamin D also stimulates the insulin receptor expression so its deficiency can cause insulin resistance(33,34). Vitamin D also acts as a hormone and regulates many gene functions directly or indirectly which influence large number of physiological functions. In our study there was negative correlation between Vitamin D and HbA1c levels. Previous studies have shown same results.(35) There is increasing risk of developing type 2 DM with increase in age, inadequate physical activity and obesity. It also occurs frequently in those with dyslipidaemia and hypertension. In our study subjects with type 2 DM had higher levels of triglycerides and LDL when compared to control group. Also blood pressure was slightly higher in DM group. In a longitudinal study contrary to association of vitamin D with type 2 DM no correlation was found between vitamin D levels and type I DM.(36).
BMI ≥25 kg/m2 is a risk factor type 2 DM.(37). In our study physical activity was seen less in type 2 DM patients when compared to control group. Moderate physical activity like brisk walking showed beneficial results in subjects with pre diabetes.(38).Moderate intensity physical activity decreases insulin resistance and reduces abdominal fat in children and adults.(39,40).Besides aerobic activity, resistance training can be included in regular physical activity which can help to prevent diabetes.