Dementia is one of the most common and the most devastating diseases of late life; approximately 4.6 million new cases of dementia are estimated to occur worldwide every year and the number of people who are affected have been predicted to double every 20 years, 42 million by 2020 and 81 million by 2040. Diabetes mellitus increases not only the risks of the mild cognitive impairment but also the risk of the progression from such an impairment to dementia. The prediction of the progression to the dementia conversion is of considerable clinical importance 
Diabetes is considered as an epidemic disease nowadays, with about 173 million diabetic people all over the world 
. Diabetes is a chronic disease which leads to long term complications, which include the risk of cognitive changes [17
]>. A preserved cognitive status is essential for the understanding of the treatment and its compliance 
The validity of the MMSE as a screening tool for detecting dementia has been extensively studied 
; its ability to detect the changes in the cognitive function for non-demented individuals has been documented mainly in the elderly 
. Many intact individuals achieve total scores of near 30 and a cut off score of 23 on MMSE, has been shown to have adequate sensitivity and specificity (86% and 91% respectively) for detecting dementia in a community sample 
We assessed the cognition status of diabetics and nondiabetics by using the MMSE and the 3MS tests. Since our subjects had educational qualifications of high school graduation and above, we used a cut off of 27 for MMSE 
.There was a highly significant decrease in the MMSE and the 3MS scores in the diabetics as compared to the nondiabetics (p<0.001). This finding was consistent with those of various studies, which showed a cognition impairment in diabetics. As compared to the people without diabetes, the people with diabetes had a greater risk of a cognitive decline 
, especially in the memory and the executive functions 
63.33% were found to have a cognition impairment by MMSE and 70% had a cognition impairment by 3MS. The 3MS shows a slightly higher percentage of the impairment, as it involves an additional number of tests and a finer discrimination of the scoring. So, we used the 3MS test for finding the correlation between the age, sex, the duration of diabetes and the HbA1C values among the diabetics. 26.67% of non diabetics showed a cognition impairment by MMSE and 20% showed it by 3MS. This might be due to benign senescent forgetfulness, depression, metabolic disorders, vascular dementia, Alzheimer’s disease, hormonal diseases, etc.
Diabetes might accelerate the cognitive decline and the conversion to dementia through a number of potential mechanisms. These include the insulin resistance syndrome, the disturbances in the insulin homeostasis in the brain, hyperinsulinaemia, interplay with the insulin degrading enzyme which is involved in both insulin and amyloid proteolysis or the effects of insulin which signal on the tau metabolism and the generation of the advanced products of glycosylation. Whatever the mechanism, with an expected increase in the prevalence of diabetes in people of all ages, which include the older adults, the risk of developing dementia may increase 
. A diabetes-induced cognitive decline may be induced via the disruption of the neurovascular coupling, not only with vascular disorders but also with the impairment of the astrocytic trafficking 
. It was observed in our study, that the educational qualification affected the MMSE and the 3MS scores. The people with graduation scored better in the cognition tests, as was observed in various studies. The median MMSE score was 29 for the individuals with at least 9 years of schooling, it was 26 for those with 5 to 8 years of schooling, and it was 22 for those with 0 to 4 years of schooling 
Various studies which were done for the correlation of age, sex, the duration of diabetes and HbA1C on the cognition impairment showed contradictory results. The patients with a longer duration of diabetes achieved a lower score test and the glycaemic control which was measured by HbA1C, had no association with the MMSE score and possible dementia in the evaluation period [5
]. We used 3MS to correlate the age, sex, the duration of diabetes and HbA1C with the cognition impairment. Even though males had decreased scores than the females, it was not statistically significant (P=0.526). The cause might be the small sample size, the small number of persons in each group, etc.
There was an inverse relationship between the MMSE scores and age, which ranged from a median of 29 for those who were 18 to 24 years of age, to 25 for the individuals who were 80 years of age and older 
. There was no correlation of the age and the duration of diabetes with the cognition status in the diabetics in our study, as the p values were 0.101 and 0.202 respectively, as per one way ANOVA. There was no correlation between HbA1C and the cognition scores (p=0.188) in our study, as per one way ANOVA. There was no correlation of the age, sex, the duration of diabetes and HbA1C with the cognition impairment in our study. The association of the independent variables such as the duration of diabetes, the control of diabetes, the complications of diabetes, the other vascular risk factors and comorbid conditions such as depression with the cognitive decline in diabetics was negative 
The early implementation of mini-mental, which is a simple method of execution, can be done to detect the early stages of dementia. This test could be an important tool for assessing the ability of the patients in understanding their disease and treatment 
. By treating the comorbid medical condition, by behavioural therapy and by cognitive training, dementia can be prevented.
The limitations of our study were that we assessed the cognition only by two tests. The other tests which are available are the Montreal cognitive assessment, the Queen square screening test, the Wechsler memory scale, the Trail making test, etc. The causes for the primary and secondary dementia were not ruled out. The early dementia which was caused by the metabolic and the structural causes was not excluded. Investigations like the lipid profile, vitamin B12, TSH, CT scan, and MRI have to be included in the study to find the other causes of dementia.
As a continuation of this study, the cognition tests can be repeated after a certain period and the impairment can be found. Other tests for the cognition assessment can be included in the study. Future studies can be done to identify the risk factors for the cognitive dysfunction and to elucidate its relationship with diabetes.