Body Mass Index and HbA1c Are Associated with Renal and Hepatic Function

Hypertension and diabetes may have implications for damage to other organs such as the kidneys and liver which are evaluated by serum creatinine and ALT, respectively. This study aims to delineate the association between body mass index and hbA1c with renal and hepatic function, respectively. This is a cross-sectional study involving 32 subjects. The research subjects consisted of diabetics and hypertension who were registered in the Muhammadiyah Primary Health Care, Kebanaran, Purwokerto. It was found that in diabetics, there were significant results between serum creatinine and HbA1c values (p <0.01, r = 0.855). Systolic blood pressure was correlated with body mass index (BMI) (p <0.01, r = 0.649). In patients with hypertension, serum creatinine was correlated with the length of time a person has hypertension (p <0.01, r = 0.475). Meanwhile, the ALT value was correlated with body mass index (p <0.05, r = 0.422) and waist circumference (p <0.001, r = 0.528). We found that a decreased HbA1c levels significantly reduces serum creatinine levels so it may also reduce kidney damage. A decrease in the value of BMI and waist circumference significantly reduces ALT enzyme levels which may have the potential for reducing liver damage.

Some non-communicable diseases are closely related to metabolic abnormalities.
Hypertension, which is a disease that affects nearly a third of the world's population (Mills, Stefanescu, & He, 2020), is closely related to metabolic abnormalities (Zheng et al., 2015;Nistala & Savin, 2017). This could be due to kidney damage due to inflammation and oxidative stress in the nephrons (Zheng et al., 2015;Nistala & Savin, 2017). In addition, diabetes is also closely related to metabolic abnormalities because it is directly related to glucose homeostasis via the GLP-1 pathway and improvements in cell membrane insulin sensitivity (Deacon, 2019). Diabetes mellitus is a disease with high morbidity and mortality (Ministry of Health of the Republic of Indonesia, 2018) where prevention strategies are one of the priority programs of the Ministry of Health of the Republic of Indonesia (Ministry of Health of the Republic of Indonesia, 2015). Therefore, the correlation between hypertension and diabetes, with metabolic abnormalities can be assumed to be the pathogenesis of insulin resistance which causes metabolic diseases such as diabetes which has implications for hypertension. Because of this, it is necessary to conduct research on the analysis of metabolic factors that affect the increased risk of morbidity for people with diabetes mellitus and hypertension.

METHODS
This study is an observational study with a cross-sectional design. The research sample was participants who were registered at the PKU Muhammadiyah Primary Health Care, Kebanaran, Purwokerto. The samples were patients who had agreed to participate in the study with informed consent according to ethical suitability issued by the ethical committee of the Faculty of Medicine, Jenderal Soedirman University. The number of samples taken was 32 people. Samples were taken by consecutive sampling method.
Anthropometric measurements are carried out by measuring height in meters (m) and body weight in kilograms (kg). Body mass index (BMI) obtained from the formula body weight (kg) divided by the square of height (m). The diagnosis of hypertension was determined if the participants had systolic blood pressure greater than 140 mmHg and/or diastole more than 90 mmHg at rest. If hypertension is controlled with drugs, the diagnosis is based on the doctor's decision at the beginning before administering the drug. Drug administration was recorded based on available medical records. The diagnosis of diabetes mellitus was given if the participants had fasting blood sugar> 126 mg / dL, or blood sugar 2 hours post prandial> 200mg / dL, or HbA1c> 6.5%, according to the diagnosis given by the previous doctor. Drug administration was recorded based on available medical records.
Peripheral blood samples were taken by aseptic venous puncture, at the location of the medial cubital vein. Blood samples were taken as much as 5 ml. The sample used was a sample from a non-EDTA vacutainer tube. Serum creatinine examination using the Jaffe Reaction Method.
SGPT/ ALT examination using the kinetic method. Mean-while, blood glucose using a spectophotometer.
Data in the form of long-suffering from hypertension and diabetes, anthropometric status, vital signs, HbA1c, serum creatinine levels, ALT/ ALT levels, and fasting blood glucose were analyzed using the Pearson Correlation test. Data is significant if p <0.05. Data processing using SPSS 20.0 for Windows software.

Subject Characteristics
A total of 32 people who were participants of the PKU Muhammadiyah Primary Health Care Kebanaran Purwokerto became participants in this study. Participants consisted of 14 men and 18 women with a mean age of 58 + 8.5 years. Patients consisted of 25 people with hypertension, 15 people with diabetes mellitus, and 8 people with hypertension and diabetes mellitus. Patients currently still routinely consume Sulfonylurea, Metformin, Insulin, Calcium channel blockers, and Angiotensin Receptor Blockers.

Correlative Analysis
Correlative analysis test results in diabetics showed significant results between serum creatinine and HbA1c values (p <0.01) with a correlation coefficient of 0.855. Meanwhile, the variables of long-suffering from diabetes, body mass index, systolic blood pressure, diastolic blood pressure, and fasting glucose were not significant.
The results of the correlation test between the systolic and diastolic blood pressure values of diabetics show that systolic blood pressure is influenced by the body mass index (BMI) (p <0.01) with a correlation coefficient of 0.649. Meanwhile, diastolic blood pressure was influenced by diabetes duration (p <0.05) with a correlation coefficient of -0.593. Other variables, namely HbA1c, fasting glucose, Serum Creatinine, and ALT were not found to be significant.
The results of the correlation analysis test between serum creatinine and other variables showed that the serum creatinine value was influenced by the length of time a person had hypertension (p <0.01) with a correlation coefficient of 0.475, parallel with previous studies (Sung et al., 2016;Yamout & Bakris, 2018). Meanwhile, the ALT value was influenced by body mass index (p <0.05 with a correlation coefficient of 0.422) and waist circumference (p <0.001 with a correlation coefficient of 0.528). The systolic and diastolic blood pressure variables did not find a significant relationship with serum creatinine and ALT values.
The data on the results of this study indicate that HbA1c is closely correlated with serum creatinine. Previous studies have also suggested that HbA1c has a strong correlation with serum closely associated with increased morbidity and mortality due to decreased renal function (Colombo et al., 2020;Willey et al., 2020). High HbA1c levels indicate an uncontrolled diabetes condition and can be a marker of higher morbidity, so that low levels are a good prognosis for the prevention of organ damage due to diabetes (Schnell, Crocker, & Weng, 2017;Langholz et al., 2021). Therefore, a decrease in HbA1c levels is important to reduce the potential for kidney damage which is represented by elevated creatinine levels.   A decrease in the value of body mass index (BMI) and waist circumference can reduce the potential for liver damage in hypertensive patients which is correlated with an increase in the ALT enzyme. The data from this study indicate that the lower the BMI will reduce the ALT level in the serum. Previous studies have shown the same thing, namely that there is a close relationship between BMI and ALT (Bilal et al., 2011;Wang, Guo, & Lu, 2016;Fan, Wang, & Du, 2018;Song et al., 2018). High ALT levels indicate liver damage (Mangus et al., 2015), so a decrease in BMI in people with hypertension can reduce the risk of liver damage.
Obesity is a risk factor for hypertension and cardiovascular disease. Obesity is characterized by a high BMI value (more than 25 kg/ m2). Previous studies have shown that reducing BMI can significantly reduce the incidence of hypertension and cardiovascular disease (Betz et al., 2018;Zhou et al., 2018;Vrettos et al., 2020). Our study data show the same thing, where BMI has a correlation with systolic blood pressure. A decrease in BMI is important to support blood pressure control because it plays a significant role in lowering systolic blood pressure.

CONCLUSION
We found that control of HbA1c and BMI are important to reduce the risk of organ damage in diabetics and hypertension. Decreased HbA1c levelssignificantly reducesserum creatinine levels so it may also reduce kidney damage. A decrease in the value of BMI and waist circumferencesignificantly reduce ALT enzymelevels which may have potential for reducing liver damage. Besides that, a decrease in BMI is important to support blood pressure control because it significantly reduces systolic blood pressure.