Absrtact
The paper presents the definition, risk factors, and complications of type 2 diabetes mellitus. Type 2 diabetes is a chronic metabolic disease characterized by hyperglycaemia. The people with hyperlipidemia, family history of diabetes, and higher body mass index are in the high risk group. The common complications of type 2 diabetes are neurologic, ophthalmologic, foot ulcer or amputation, renal hypertension, coronary artery and chronic kidneay diseases. The results of the numerous trials, cases, and researches are presented. The modern understanding of anti-diabetes therapy includes pharmacological treatment, correction of the diet (calories restriction and adequate sodium intake), minimization of sedentary time, and the active life-style. These measures are directed to prevention of the complications development. The moderate physical activity was proved as an effective way to avoid diabetes development. Regular glucose screening was recognized important for diabetes risk reduction. The significant preventive actions for public health improvement are educational programs about diabetes and popularization of active life-style.
Introduction
Shah & Vella (2014) describe type 2 diabetes mellitus (T2DM) as a chronic disease characterized by failure of glucose metabolism and manifestations of hyperglycemia. Nowadays, this disorder is no more exotic in the developed world. Due to wide availability of food and popularization of junk food, the registered cases of diabetes are counted in millions. Thus, Schellhase et al. (2003) reported about 14 million of diabetes cases in the USA.
Type 2 Diabetes Mellitus Characteristics
The level of glucose increases because of relative or absolute insulin deficiency. Type 2 diabetes is closely associated with obesity: the high body mass index (BMI) increases the risk of T2DM development. The terms of glycaemia that indicate the diabetes mellitus are: fasting plasma glucose more than 7.0 mmol/L (126 mg/dL) or random plasma glucose more than 11.1 mmol/L (200 mg/dL). The high glucose concentrations lead to microvascular complications, such as retinopathy. The term ‘pre-diabetes’ was recentrly replaced with ‘impaired fasting glucose’ and/or ‘impaired glucose tolerance’ and is defined by following glucose levels: fasting plasma glucose between 5.6 mmol/L (100 mg/dL) and 7.0 mmol/L (129 mg/dL), or a 2-hour plasma glucose after oral glucose tolerance testing between 7.8 mmol/L (140 mg/dL) and 11.1 mmol/L (200 ng/dL) (Shah & Vella, 2014).
T2DM is characterized by defective and delayed insulin secretion that leads to the suppression of glucose production after meal, which causes hyperglycaemia. The islets in the pancreas of people with T2DM is characterized by the prominent amyloid deposition and decrease in β-cells functioning (Shah & Vella, 2014).
There are numerous drugs that inhibit glucose metabolism and induce diabetes (antiviral drugs – interferon, protease inhibitors; immunosuppressants – corticosteroids, ciclosporin; antipsichotics – cozapine, risperidone; niacin, pentamidine, β-blockers, thiazides) (Shah & Vella, 2014).
Glucose Screening and Risk of Complications in Type 2 Diabetes Mellitus
The diabetes can be present for 7-10 years before it is diagnosed, and during this time the complications can develop. The most common complications are microvascular that lead to end-stage renal disease, polyneuropathy, non-traumatic amputations, and blindness.
The control study with 303 T2DM cases with at least one symptomatic microvascular diabetic complication showed the following results. The most common initial complication of the T2DM was neurologic (64% of all first complications), ophthalmologic (16.5%), foot ulcer or amputation (13.9%), and renal (5.6%). Case subjects (compared with control) were more likely to have hypertension, coronary artery disease, hyperlipidemia, a family history of diabetes, and higher BMI. The data of this study suggested that people who had at least one glucose screening test during 10 years had a 13% reduction of T2DM complications. The authors of this study expect that T2DM screening can help to identify individuals with risk factors for macrovascular disease (hypertension and hyperlipidemia). Therefore, diabetes screening may be associated with lower risk of diabetic complications development listed above (Schellhase et al., 2003).
Dietary Sodium Intake in Type 2 Diabetes
Provenzano et al. (2014) studied the influence of sodium intake by people diagnosed with T2DM. As it was mentioned above, patients with T2DM have high risk of cardiovascular disease (hypertension) development. Excess sodium intake is very harmful for people with hypertension because it increases intravascular volume and decreases the effectiveness of antihypertensive drugs. From the other side, decreased sodium intake decreases blood pressure levels. The level of hypertension in USA is very high today. It is known that more than one third of people who are older than 20 years have hypertension (Provenzano et al., 2014). It has been proved that sodium causes hypertension, and the majority of people consume excess quantities of sodium The research trial test by Provenzano et al. (2014) included 251 respondents who were diagnosed with diabetes 1 (20.8%), 1-5 (39.2%), and more than 5 (40%) years ago. Most of the people were 45-64 years old (67.7%), and some also had cardiovascular desease (14.5%) and chronic kidney desease (11.6%), and some took insulin injections (20.7%). It showed that decrease of sodium intake decreases frequency of hypertension in people with T2DM.
Type 2 Diabetes Sits in a Chair
Physical activity (or its absence) plays a major role in the development of T2DM. In general, physical activity improves health and decreases risk of chronic diseases. The lack of light physical activity causes multiple chronic diseases, including T2DM. Nowadays, the absolute amount of people with T2DM extremely increases. So, it is important to find an effective preventive methods and treatment. Solomon & Thyfault (2013) present the results of various trials which show that the right diet and light physical activity delays the onset of T2DM in subjects with prediabetes. These trials indicate the preventive effect of physical activity in development of T2DM. It was also found that an antidiabetic medication together with physical activity had greater effect on hyperglycaemia levels than pharmaceutical therapy only. The level of physical activity was found important by various tests. For example, the National Runners Health study stated that 8 km/week run lowers the risk of diabetes better than less than 8 km/week run. Longitudinal studies have shown that an acute transition from higher to lower levels of physical activity for a period of time leads to a reduction of insulin sensitivity and glucose tolerance. Unfortunately, today the majority of people carry out sedentary life-style, i.e. they are sitting or lying the most part of a day. In those cases, even adequate physical activity will not decrease the risk of diabetes. Solomon & Thyfault (2013) mentioned the research by National Health and Nutrition Examination Survey which stated that long-duration sitting with short bouts in obese office workers lowered glucose responses to mixed meals. Diabetes Prevention Program focused on the lifestyle modification in high-risk group. It was noticed that caloric restriction and exercising led to the reduction in the incidence of diabetes after 3 years. The same modification was realized among people with diabetes and the results were also sufficient. It was proved that early pharmacotherapy of T2DM (oral agent, such as acarbose, metformin, thiazolidinedione and others) can prevent diabetes or induce remission. Batriatric (weidht loss) surgery proved that weight loss improves the glycaemic control (Shah & Vella, 2014).
It is clear that physical activity and reducing sitting time improve glycaemic control in patients with T2DM. Hence, it is important to provide clear education to general public about pathology of T2DM, influence of sedentary lifestyle. (Solomon & Thyfault, 2013).
Conclusions
The Type 2 Diabetes mellitus is a chronic metabolic disease characterized by hyperglycaemia, which is caused by relative or absolute insulin deficiency. Numerous complications are associated with T2DM, including retinopathy, neuropathy, nephropathy, hypertension, etc. The recent researches showed that complications cannot be prevented by single pharmaceutical treatment. In addition, the lifestyle adjustment has to be performed, such as adequate diet with the appropriate sodium intake, increase of the physical activity, and minimization of “sitting on chair” time.
References
Shah M. & Vella A. (2014). What is type 2 diabetes? Medicine, 42, 687-691.
Schellhase, K.G., Koepsell, T. D., Weiss, N.S., Wagner, E. H., Reiber, G. E. (2003). Glucose screening and the risk of complications in Type 2 diabetes mellitus. Journal of Clinical Epidemiology, 56, 75-80.
Provenzano, L. F., Steenkiste, A. , Piraino, B. and Savick, M. A. (2014). Dietary sodium intake in Type 2 diabetes. Clinical diabetes, 32, 106-12.
Solomon, T. P.J & Thyfault, J. P. (2013). Type 2 diabetes sits in a chair. Diabetes, Obesity and Metabolism, 15, 987-992.
