Family History of Diabetes or Prediabetes—An Opportunity to Intervene!!

Dear Editor, This article comments on “An Early Decline of Cognitive Functions in Healthy Individuals with Family History of Diabetes in South India: A Comparative Analysis with Diabetics and Healthy Control” by Rout and Radhakrishnan.[1] This study gives a very comprehensive description of the affected cognitive domain for visual stimuli in diabetics and of those who are at higher risk. A very good article from the diabetes, pre-diabetes, and metabolic syndrome point of view. Recently, there has been increasing evidence of prediabetes state, which has been linked to an increased risk of cognitive decline and dementia, potentially starting even before the frank onset of type 2 diabetes mellitus (DM).[1‐3] Different markers of prediabetes have been coupled to the risk of dementia and cognitive decline, including deficits in global cognitive function, processing speed, and executive functioning.[2,4,5] Studies have shown that impaired fasting glucose, insulin resistance, and higher glycosylated hemoglobin concentrations predict the increased incidence of dementia.[6,7] The mechanisms that are implicated in prediabetes states have contributed to cognitive decline and may include arteriosclerosis, micro-vascular disease, insufficient insulin action, oxidative stress, and glucotoxicity.[6] The duration of diabetes, including the pre-diabetic phase, remains to be an important factor in these risk associations. Thus, the cognitive decline may start much before the diagnosis of DM, that is, even in the pre-diabetic state.[1] A positive family history of type 2 DM is an additional risk factor for the first-degree relative of diabetes and pre-diabetes. But at the same time, it can serve as an effective tool for the screening of pre-diabetes itself particularly in asymptomatic individuals.[1,8] Very few studies in India have assessed cognitive function in healthy individuals with a family history of diabetes. One study from Kerala (South India) has demonstrated that there is decreased metacognitive awareness, especially significantly decreased metacognitive knowledge in asymptomatic students with a family history of diabetes.[9] The study by Rout and Radhakrishnan too demonstrated that asymptomatic individuals with a family history of diabetes displayed significant delays in their visual memory span and visual search time, similar to diabetic individuals.[1] Prediabetes is usually asymptomatic and is often accompanied by obesity, dyslipidemias with high triglycerides, low high density lipoprotein (HDL) cholesterol and hypertension which are the independent risk factors for cognitive decline.[1,8] Hence, the presence of family history of type 2 DM in first degree relative, should prompt comprehensive screening for prediabetes, diabetes and its related complications, especially in asymptomatic individuals. Apart from the family history of diabetes, history of cardiovascular disease, hypertension, dyslipidemia, polycystic ovary syndrome, physical inactivity, severe obesity, acanthosis nigricans, and metabolic dysfunction, etc. can be considered as screening tools, especially in asymptomatic individuals, as all these are risk factors for developing diabetes or prediabetes.[8] Thus, a family history of diabetes can serve as an effective screening tool to identify at-risk individuals to potentially retard the process of cognitive decline. As per a recently published ICMR report in Lancet (2023), the prevalence of prediabetes and it’s associated risk factors is much higher in India than anticipated. In India, the overall weighted prevalence of diabetes is 11.4%, prediabetes 15.3%, hypertension 35.5%, generalized obesity 28.6%, abdominal obesity 39.5%, and dyslipidemia 81.2%.[10] Considering all these, as we all are standing in the middle of diabetes epidemic, prediabetes and family history of type 2 DM offer an opportunity to be explored, suggesting the scope of proactive intervention and management of raised blood sugar levels by lifestyle modifications and therapeutic interventions for increasing insulin sensitivity and ultimately to modify the course of early cognitive decline in diabetics and pre-diabetics. Acknowledgments The author would like to express her gratitude towards the Editorial team and to the contributors of the referred article. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.