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Pre-Diabetes: Looking over the fence to Diabetes Mellitus

Despite all the research studies and broadcast, diabetes is still a fast-growing worldwide epidemic. People with pre-diabetes suffer from certain metabolic conditions that may lead to diabetes; therefore, early detection of the disease is crucial to treat it on time.

“The prelude to diabetes is prediabetes, in what can be described as a continuum from normoglycemia through worsening dysglycemia. Prediabetes is defined specifically as impaired glucose tolerance and/or impaired fasting glucose. According to the American Diabetes Association (ADA) impaired glucose tolerance (IGT) is defined as a 2-hour plasma glucose value in the 75-gram oral glucose tolerance test (OGTT) of 140 mg/dL (7.8 mmol/L) to 199 mg/dL (11.0 mmol/L). Impaired fasting glucose (IFG) is defined as a fasting plasma glucose of 100 mg/dL (5.6 mmol/L) to 125 mg/dL (6.9 mmol/L).”

Finally, prediabetes can also be defined as a hemoglobin A1c (HbA1c) of 5.7% –6.4% (39–46 mmol/mol). It bears stressing that the ADA criteria stipulate normal glucose tolerance (NGT) as a fasting glucose level less of than 100 mg/dl and a 2-hr post-load OGTT plasma glucose level of less than 140 mg/dl. In regards to using HbA1c as a diagnosis of prediabetes, it must be stressed that there are many well-characterized ‘pitfalls’ such as anemia, chronic kidney disease, and other systemic illness and hematological disorders that disrupt the reliability of HbA1c as an integrated measure of mean plasma glucose. In particular, racial and ethnic differences in the relationship between blood glucose values and HbA1c call for caution when utilizing HbA1c levels for the diagnosis of prediabetes. It is always prudent to confirm the diagnosis with actual blood glucose measurements before instituting therapeutic measures.

Estimates by the Centers for Disease Control and Prevention (CDC) in the United States indicated that there were ~29 million adults with diabetes and 86 million with prediabetes in 2014. Worldwide, there are more than 400 million people with prediabetes and projections indicate that more than 470 million people will have prediabetes by 2030. In addition, many studies from across the globe have pointed out that the risk of many comorbidities are the same in diabetes and prediabetes and affect all age groups.”1

As stated above, scientific research centers and worldwide organizations have dedicated years of work to discover new developments and collect information regarding Pre-Diabetes. They have concluded that, even if preventable, pre-diabetes is the major predictor of developing diabetes mellitus. According to the World Health Organization (WHO), it is one of the leading causes of death of millions per year.

Rise of Pre-Diabetes

Obesity and a sedentary lifestyle have their own place in the history of medical literature and still prevail in modern society. Therefore, following a healthy diet and exercise regime becomes difficult.

Technology has consumed multiple forms of entertainment to attract the attention of the average person. As a result, physical activities such as playing sports, riding bicycles, and running become unpopular. Currently, watching television, surfing the web, investing time in social media and video games are some sedentary activities leading to pre-diabetes.

There must be a balance between rest, exercise and diet. As for exercise, include it progressively in your routine if you are not used to it. Overall, 30 minutes worth of cardio is a good start, though this varies from person to person.

Regarding eating habits, daily caloric needs are quite high for the modern adult lifestyle. People cannot invest time in healthy and carefully planned cooking, and the food industry provides numerous unhealthy options. Obesity is prevailing despite all the consciousness-raising, scientific data and multiple diets to choose from, as the conditions are ripe for its persistent presence.

Lifestyle changes can be overwhelming because humans are creatures of habit. Diet trends that promise immediate weight loss are unsustainable in the long run, and fail to change dietary habits and physical outputs. Consequently, these diets do not receive much recognition from nutritionists and scientists.

Recognized pathophysiological defects

““FPG (fasting plasma glucose) values are determined by endogenous glucose production (EGP), which depends mostly on the liver. EGP and fasting insulin are used as markers of hepatic insulin resistance and show a strong relation with fasting glycemia. During absorption of a glucose-containing meal, changes in glucose concentrations are caused by intestinal absorption, suppression of EGP, and total body glucose uptake. EGP is greatly suppressed in people with normal glucose tolerance after glucose ingestion, whereas this suppression is less pronounced in prediabetes and diabetes. In type 2 diabetes, total body glucose disposal is decreased, and 85–90% of this impairment is related to muscle insulin resistance. If insulin secretion was able to compensate for insulin resistance perfectly, no observable changes in glucose concentration would occur. This factor means that, by definition, β-cell dysfunction is already present in the prediabetic phase. However, β-cell function cannot be characterized solely on the basis of insulin secretion without consideration of underlying insulin resistance. β cells respond to an increase in glucose concentration with a rise in insulin secretion that is dependent on whole-body insulin sensitivity. Accordingly, the relation between insulin secretion and insulin sensitivity is hyperbolic, and the ratio of incremental insulin to incremental glucose divided by insulin resistance is described by a constant known as the disposition index. This index, therefore, is a measure of insulin secretion after the underlying degree of insulin resistance (higher for healthy people and lower for prediabetic and diabetic individuals) has been accounted for. Studies using different measures of β-cell function have reported severely abnormal (up to 80% decreased) insulin secretion in prediabetic people.”2


Hyperglycemia chart
Hyperglycemia chart. [3]

Pre-diabetes occurs when the body reaches a range of blood glucose and insulin levels but is not high enough to consider it diabetes. A blood glucose test may confirm pre-diabetes (after 8-14 hours of fasting) if it reads between 6.0 mmol/L – 6.9 mmol/L (WHO). A person is at a major risk of diabetes when marking 7.0 mmol/L.

Prevent Pre-Diabetes

Pre Diabetes is a precursor to diabetes mellitus.  Insulin, as an endocrine hormone produced by the pancreas, collects glucose molecules in the bloodstream and transports them to cells for energy. When eating,  the digestive system breaks food down to glucose. Afterward, the pancreas reacts and releases insulin. While digesting, insulin levels rise. As food becomes scarce, so do glucose and insulin.

When dietary habits cause obesity (generally considered a BMI greater than 25) insulin struggles to handle all the glucose molecules in the bloodstream, causing cells to slowly become resistant to insulin. As resistance to insulin increases, people lose their ability to control blood glucose, and thus, get high blood sugar.

“Prediabetes should be treated to prevent progression to diabetes, mitigate some of the potential results of progression to diabetes, and prevent the potential effects of prediabetes itself. Most studies in this research specialty have focused on diabetes incidence in prediabetic individuals, and support the notion that lifestyle change should be the cornerstone for diabetes prevention.”4 

“There are currently four medications for treating the prediabetes subpopulation, including metformin, pioglitazone, acarbose, and liraglutide. In addition, the American Association of Clinical Endocrinologists (AACE) has also proposed three weight-loss therapies—including orlistat, lorcaserin, and phentermine/topiramate ER—to manage obesity with the goal of halting the progression of insulin resistance and type 2 diabetes.”5


Prediabetes Lifestyle Intervention
Prediabetes Lifestyle Intervention. [6]

“The combination of diet and exercise is arguably the single most important factor that could halt the progression towards type 2 diabetes in patients with prediabetes. Among the first studies to prove this was the Finnish Diabetes Prevention Study (DPS), a controlled randomized trial including 522 overweight subjects with impaired glucose tolerance who were randomized to either an intensive lifestyle intervention group or a standard-of-care control group. The intensive lifestyle intervention group received individualized dietary counseling and circuit-type resistance training and were advised to increase overall physical activity, whereas the control group received general counseling on diet and exercise along with an annual physical exam. The lifestyle intervention arm of the study was designed to be at a high intensity during the first year, followed by a maintenance period, with the goal of reducing both weight and dietary fat intake while increasing physical activity and dietary fiber. Weight reductions were measured after 1 year and at 3 years; the intervention group lost 4.5 kg and 3.5 kg while the control group lost 1.0 and 0.9 kg, respectively. Lipid and glycemic parameters showed more improvement in the intervention group, with a 58% reduction in the risk of developing diabetes compared to the control group. The subjects who were free of diabetes at the end of the intervention were followed up for an additional 3 years, and the incidence of diabetes, physical activity, and dietary intake of fiber and fat was measured. During the total 7-year follow-up period, the study concluded that the incidence of type 2 diabetes was 4.3 versus 7.4 per 100 person-years in the intervention and control group, respectively (log-rank test P = .0001), indicating a 36% reduction in relative risk.”7

Diabetes can lead to complications such as cardiac disease, blindness, kidney failure, and neurological disorder; therefore, it is vital to find ways to prevent it. In addition, pre-Diabetes is the result of a confluence of bio-factors that have caused the medical community and patients much turmoil and stress. The bright side is, people have the choice to change their habits. Working out does not mean getting a gym membership. Diabetes prevention can start by swimming, hiking, bicycling, gardening, jogging/running, carpentering, having sexual relations, dancing, and the list goes on.


(1, 3) Prediabetes and Cardiovascular Disease: Pathophysiology and Interventions for Prevention and Risk Reduction. Brannick, B. Endocrinology and Metabolism Clinics of North America. 2018. 

(2, 4) Prediabetes: a high-risk state for diabetes development. Tabák, A.G., Herder, C., Rathmann, W., Brunner, E.J. & Kivimäki, M. The Lancet. 2012.

(5, 6, 7) Prediabetes: Why Should We Care?. Zand, A., Ibrahim, K. & Patham, B. Methodist DeBakey Cardiovascular Journal. 2018. 


María Laura Márquez
13 October, 2018

Written by

María Laura Márquez, general doctor graduated from The University of Oriente in 2018, Venezuela. My interests in the world of medicine and science, are focused on surgery and its breakthroughs. Nowadays I practice my more:

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