Original Articles

A Study of Lipid Profile in Patients with Type -2 Diabetes Mellitus

Ramu Kandula¹, Vinayak E. Shegokar²

¹Consultant Physician, Challa Hospital, Ameerpet, Hyderabad. ²Professor and Head of Medicine, Malla Reddy Institute of Medical Sciences, Hyderabad

 

Abstract

Background: It is clear from the population based studies that type-2 diabetes generally is associated with a 50% to 100% elevation in the plasma levels of total and VLDL triglycerides. Objective: To find the pattern of Dyslipidemia in type-2 diabetics in comparison with non diabetic individuals. Methods: A case control study was conducted. Hundred type-2 diabetes mellitus patients were taken as cases and hundred age and sex matched non diabetic individuals were taken as controls. The labeling of dyslipidemia was based on NCEP guidelines. Results: Dyslipidemia was present in 86% of diabetic patients. LDL dyslipidemia was observed in 64%, HDL dyslipidemia in 71% and hypertriglyceridemia in 47% and hypercholesterolemia in 41% of diabetic patients. The total cholesterol, triglycerides, LDL-C are significantly elevated in diabetics when compared to control (p=0.003, p<0.0001, p<0.0001) while HDL-C values are significantly lowered in diabetics when compared to Non-diabetics (p=0.007). Conclusion: The alteration of lipid metabolism of type-2 diabetics has raised a serious medical concern with respect to vascular complications like coronary artery disease, cerebro vascular diseases and the recommendation of greater routine evaluation of serum lipid profile, its treatment and good glycemic control in patients of type-2 diabetes mellitus is strongly suggested.

Key words: lipid profile, NCEP guidelines, triglycerides

Corresponding Author: Dr. Ramu Kandula, Consultant Physician, Challa Hospital, Ameerpet, Hyderabad. Email: drramgmc99@gmail.com

 

INTRODUCTION

Diabetes is the commonest metabolic disorder affecting the people all over the world. In 2010 approximately 285 million people worldwide had diabetes and more than 438 million people worldwide will have diabetes by 2030. The number is climbing steeply. India has the dubious distinction of having the largest number of people with diabetes which is around 50.8 million in 2010 and is rising to 87 million by 2030 ^[1]. Economic drift and its consequent changes in life style in India have lead to this alarming increase in the prevalence of diabetes which has now become the greatest health threat.

The most common alteration of lipoprotein in type-2 diabetes mellitus is hyper triglyceridemia caused by an elevation in VLDL concentration. In type - 2 diabetes mellitus with severe hyperglycemia, the clearance rate for LDL apo-B is reduced. ^[2] Mildly hyperglycemic individuals with type-2 diabetes mellitus may have increased LDL production as well. So LDL levels in type-2 diabetes mellitus can be either increased or decreased depending upon hyperglycemia.

HDL in type-2 diabetes mellitus is usually decreased due to increased rate of HDL clearance as measured by apo-A₁ and apo-A₂ kinetics. ^{[3, 4]}

The above mentioned lipid abnormalities will lead to micro vascular and macro vascular diseases in diabetic patients. ^[5] Lipoprotein abnormalities correlated with large vessel disease are seen in diabetics and non diabetic populations; however atherogenesis is accelerated in diabetics. ^[6]

There is a higher incidence of Diabetes Mellitus in South India. ^[7] There are many patients of Diabetes Mellitus with its complications are attending MNR Medical College and Hospital which is situated in rural area of Medak district of Andhra Pradesh. No study was carried out on lipid profile in type-2 diabetes mellitus with its complications in this area. Therefore study of lipid profile in patients with Type-2 Diabetes Mellitus is taken.

MATERIALS AND METHODS                                  

Source of data: The subjects for this hospital based case control study were selected from MNR Medical College and Hospital, Fasalwadi.

Method of collection of data:

From the patients of MNR Medical College & Hospital, Fasalwadi 378 cases of type-2 diabetes mellitus were selected. After following the inclusion and exclusion criteria, 100 cases were found eligible for the study. Age & Sex matched 100 Non – Diabetic healthy individual were selected randomly from the attendants of patients,

hospital staff and were assigned as controls. The diagnosis of Diabetes is based on guidelines of American Diabetes Association. Informed consent was obtained from cases and controls.

Study Design: Case control study.

Study Period: September 2009 to August 2011

Inclusion Criteria:

All patients with type 2 Diabetes Mellitus.

Exclusion Criteria:

Type 2 Diabetes Mellitus patients associated with concomitant diseases or conditions affecting the lipid levels like thyroid disorders, Renal diseases, Chronic Liver diseases, Familial Hyperlipidemia (History wise), on lipid lowering agents, Protease inhibitors or other drugs known to alter lipid profile etc., were excluded.

Exclusion criteria were implemented based upon clinical examination and necessary investigations.

Fasting blood samples from all the diabetic patients as well as controls were collected early morning between 8.00 AM to 9.00 AM. Collected blood samples were centrifuged and allowed to form serum. Serum total cholesterol (TC), ^{[8, 9]} serum low-density lipoprotein cholesterol (LDL-C), serum very low-density lipoprotein cholesterol (VLDL-C), serum high-density lipoprotein cholesterol (HDL-C) and serum triglycerides (TG) ^[10] were assayed using enzymatic estimation kit (ERBA-Diagnostics Manheim, GmbH, Germany). ^{[11, 12]} The experimental protocol was ethically cleared by institutional ethical committee as per the guidelines of Declaration of Helsinki R.

Statistical methods: Mean + SEM values were calculated for male and female control groups as well as respective diabetic groups. Student’t’ test was performed to find out the level of significance between the control group and diabetic groups of male and female separately. Statistical analyses were done by using SPSS software version 16.0 (Chicago IL, USA).

RESULTS

Total number of males was 57 (57%); females were 43(43%). Maximum Number of cases i.e.62% were between the age group of 40 and 59. Male to female ratio was 1.32: l (Fig. 1).

Total Cholesterol (TC) mean values were compared between cases and controls as shown in table 1. It was found that the mean TC values for males in all age groups were significantly higher in cases as compared to controls (p < 0.05). Similar finding was observed in case of females, except in the 30 –

Fig.1: Distribution of the study subjects according to age and sex

 

39 years and more than 60 years of age group. In these two age groups in females, the difference in the mean values between cases and controls was statistically not significant (p > 0.05).        

Table 2 shows comparison of mean values of triglyceride (TG) among cases and controls for both the genders. It was observed that the difference in the mean values of TG for male cases and controls in all age groups was statistically significant (p < 0.05). Same was found true for female cases and controls except in the age group of 30 – 39 years, where the difference in the mean value of TG was statistically not significant (p > 0.05).

The age wise mean values of High Density Lipoprotein (HDL) for male and female diabetic and non diabetic subjects are shown in table 3. In males, the mean HDL values in all age groups were higher when compared to controls and this difference was statistically significant across all age groups (p < 0.05). Similar was the observation for female cases and controls, but this difference of mean value of HDL in the age group of 30 – 39 years was statistically not significant (p > 0.05).

Low Density Lipoprotein (LDL) mean values for all age groups both for male and female cases and controls are shown in table 4. It was found in case of males that this difference of mean values of LDL between cases and controls was not significant (p > 0.05) in 30 – 39 and 40 – 49 years of age groups. But it was statistically significant (p < 0.05) in older age groups i.e. in 50 – 59 and more than 60 years of age groups. When the difference in the mean values of LDL was observed in female cases and controls, it was found that the difference was not significant (p > 0.05) in the 30 – 39 and more than 60 years of age group. This difference was significantly more (p < 0.05) as seen in the age group of 40 – 49 and 50 – 59 years.

 

Table 1: Total Cholesterol Values (mg/dl) in cases and controls

 

Age group (years)	Males			Females
	Cases	Controls	p value	Cases	controls	p value
30-39	188.66+25.03	155.11+31.45	0.02	185.42+36.50	162.85+12.79	0.14
40-49	205.50+39.47	153.70+11.83	0.06	222.37+36.64	189.93+31.01	0.01
50-59	224.66+39.32	171.93+43.46	0.001	216.63+34.38	169.09+26.33	0.001
> 60	228.53+34.64	159.30+34.87	0.0001	217.88+47.18	185.99+52.85	0.19

 

*Total cholesterol variations in male and female subjects are given as mean + standard deviation

 

Table 2: Triglycerides values (mg/dl) in cases and controls

Age group (years)	Males			Females
	Cases	Controls	p value	Cases	controls	p value
30-39	166.11+24.02	109.11+32.81	0.0007	140.00+49.54	105.14+32.78	0.14
40-49	293.90+36.68	152.60+27.25	0.000	186.12+38.16	132.43+44.57	0.001
50-59	235.73+32.38	143.66+13.95	0.005	201.81+43.77	111.90+33.10	0.000
> 60	249.07+7761	149.23+58.76	0.001	222.55+62.65	123.00+65.89	0.004

 

*Triglyceride values in male and female subjects are given as mean + standard deviation

 

Table 3: High Density Lipoprotein (HDL) values (mg/dl) in cases and controls

Age group (years)	Males			Females
	Cases	Controls	p value	Cases	controls	p value
30-39	38.00+4.74	40.44+3.43	0.02	46.42+6.13	50.28+5.18	0.22
40-49	36.65+3.23	40.47+3.40	0.0009	44.37+7.31	49.75+6.38	0.03
50-59	36.00+2.87	39.03+4.84	0.04	41.63+3.93	48.09+8.43	0.03
> 60	30.30+5.64	36.23+8.63	0.04	45.22+5.58	47.77+8.77	0.04

 

*HDL values in male and female subjects are given as mean + standard deviation

 

 

 

Table 4: Low Density Lipoprotein (LDL) values (mg/dl) in cases and controls

Age group (years)	Males			Females
	Cases	Controls	p value	Cases	controls	p value
30-39	118.00+24.02	92.44+30.05	0.06	107.14+10.26	91.95+16.68	0.06
40-49	113.00+39.59	92.95+10.54	0.07	141.50+30.91	114.06+25.07	0.009
50-59	139.66+38.15	105.13+28.20	0.0084	130.63+28.12	98.63+14.67	0.03
> 60	145.30+31.04	98.23+27.25	0.0004	128.55+35.13	114.44+34.45	0.16

 

*LDL values in male and female subjects are given as mean + standard deviation

 

 

 

DISCUSSION

In the present study, in Diabetic group there is significant elevation of Total Cholesterol when compared to Non-Diabetic healthy individuals (p = 0.003). But between male and female diabetics there is no statistically significant difference. (p = 0.60). This is comparable to the study done by Sapna Smith et al. ^[13]

The serum triglyceride was also significantly increased in diabetic group (p < 0.0001). The diabetic males had significant higher values when compared to diabetic females (p = 0.002). Sapna Smith et al ^[13] and Suryavanshi et al ^[14] also reported similar results.

The LDL-C was significantly higher in diabetic group when compared to control (p < 0.0001). But there was no statistically significant difference observed between male and female diabetics (p = 0.14). Sapna Smith et al ^[13] also reported similar observation but in their study the LDL-C was significantly elevated in diabetic male when compared to diabetic female (p < 0.0001).

The HDL-C was significantly lower in diabetics when compared to non-diabetics (p = 0.007). Suryavanshi et al ^[14] also reported similar results.

An interestingly higher percentage of dyslipidemia (86%) has been found in type-2 diabetic in present study as compared western data (50%- 60 %). The major concerning fact found in this study is the high percentage of HDL dyslipidemia (71%). LDL dyslipidemia was 64% which is similar to western data (60-80%). But hyper triglyceridemia of more than 200 mg/dl was seen in 47% as compared to 39% of PROCAM study. ^[15]

In a study conducted in Nigeria, ^[16] 89% of people with diabetes had dyslipidemia. Total cholesterol was elevated in 42%, Total triglycerides was elevated in13%, LDL-C elevated in 74%, low HDL seen in 53%.

In a study conducted in Botswana ^[17] among 401 patients, 33.5% had hypercholesterolemia and 38.9% had hypertriglyceridemia where as in present study 41% had hypercholesterolemia and 47% had hypertriglyceridemia.

In Indian studies, Udawat et al ^[18] reported dyslipidemia in 89% of type-2 diabetic patients, comparable to 86% of the present study. LDL hyper lipoprotinemia more than 100 mg/dl in 73% was comparable to 64% in present study. HDL dyslipidemia less than 35 mg/dl among -58% (Udawat et al) which is comparable to 71% in present study (HAD values are <40 for men and <50 for women.

The UKPDS study ^[19] showed that the coronary artery disease was significantly associated with increased concentration of lower density lipoprotein, decreased HDL concentration and increased TG concentrations.

The earlier Indian studies have also compared the lipid profile in diabetic and non diabetics. Bhu et al ^[20] observed higher level of cholesterol and LDL level in diabetics whereas Hardas et al ^[21] found only higher triglycerides levels in diabetics. Kodali et al ^[22] reported the prevalence of hyperlipidemia in 34% of type 2 diabetic subjects.

Walia et al ^[23] observed hypercholesterolemia in 43.6%, hypertriglyceridernia in 52.5%, HDL dyslipidemia in 42% and LDL dyslipidemia in 29.9% where dyslipidemia was labeled when total cholesterol > 200 mg/dl, HDL is less than 40 mg/dl, TG more than 150 mg/dl and LDL more than 140 mg/dl. In present study 64% was the LDL dyslipidemia noticed taking LDL value more than 100 mg/dl. The difference between the present study and the above two studies is probably due to the different cut off values taken for labeling dyslipidemia.

Conclusion:

A significant increase in serum Total Cholesterol, Triglycerides and LDL-C along with a significant decrease in serum HDL-C among diabetics as compared to non diabetics was observed. Levels of Total cholesterol, Triglycerides, LDL-C are increased and levels of HDL-C are decreased, as the age advances and the duration of diabetes increases. The dyslipidemia is more in patients with poor glycemic control

References:

1. IDF Diabetes Atlas, 4^th ed. International Diabetes Federation 2009.

2. Howard BV, Abbott WG, Beltz WF, Harper IT, Fields RM, Grundy SM, et al. Integrated study of low density

          lipoprotein metabolism and VLDL metabolism in non-insulin dependent diabetes mellitus. Metabolism 1987

          Sep;36(9):870-7.

3. Golay A, Zech L, Shi MZ, Chiou YA, Reaven GM, Chen YD. HDL metabolism in NIDDM measurement of HDL turn over, using titrated HDL. J Clin Endocrinol Metab. 1987 Sep;65(3):512-8.

4. Taskinen MR, Kahri J, Koivisto V, Shepherd J, Packard CJ. Metabolism of HDL apolipoprotein A-I

          and A-II in Type-1 diabetes mellitus. Diabetologia l992;35(4):347-56.

5. Chaturvedi N, Fuller JH, Taskinen MR; EURODIAB PCS Group. Differing associations of lipid and

           lipoprotein disturbances with the macrovascular and microvascular complications of type-I diabetes.

           Diabetes care 2001;24(12):2071-7.

6. Mazzone T. Current concepts and controversies in the pathogenesis, prevention and treatment of the

           macrovascular complications of diabetes. J Lab Clin Med 2000;135:437- 43.

7. Mohan V, Sandeep S, Deepa R, Shah B, Varghese C.   Epidemiology of type 2 diabetes: Indian scenario. Indian J Med Res 2007 March;125:217-30
8. Roeschlau P, Bernt E, Gruber W. Methods of Enzymatic Analysis. 2nd English Editon, H.U Bergmeyer, ed. Academic Press, New York (1974).
9. Flegg HM. Ann Clin Biochem. 1973;10:79.
10. Fossati P, Prencipe L. Serum Triglycerides determined colorimeterically with an enzyme that produces hydrogen peroxide. Clin Chem. 1982 Oct;28(10):2077-80.
11. Ford ES, Li C, Sattar N. Metabolic syndrome and incident diabetes: current state of the evidence. Diabetes Care 2008; 31:1898.
12. Stern MP, Williams K, González-Villalpando C, Hunt KJ, Haffner SM. Does the metabolic syndrome improve identification of individuals at risk of type 2 diabetes and/or cardiovascular disease? Diabetes Care. 2004 Nov;27(11):2676-81. Erratum in: Diabetes Care. 2005 Jan;28(1):238.
13. Sapna Smith, Alok M Lall. A Study on Lipid Profile Levels of Diabetics and Non- Diabetics Among Naini Region of Allahabad, India. Turkish J Biochem 2008;33(4):138–41.
14. Suryawanshi NP, Bhutey AK, Nagdeote AN, Jadhavand AA, Manoorkar GS. Study of lipid peroxide and lipid profile in Diabetes mellitus.Indian J Clin Biochem. 2006;21(1):126-130.
15. Assman C, Shulte H. Relatio of high density lipoproteins and triglycerides to incidence of atherosclerotic coronary artery disease: the PROCAM experience. Am J Cardiol 1992;70(7):733-7.
16. Ogbera AO, Fasanmade OA, Chinenye S, Akinlade A. Characterization of lipid parameters in diabetes mellitus - a Nigerian report. Int Arch Med. 2009;2(1):19.
17. Addisu Y, Mengesha MD. Lipid profile among diabetes patients in Gaborone, Botswana. S Afr Med J. 2006;96:147.
18. H Udavat. R K G. Goyal, A Maheswary. Coronary risk and dyslipidemia in type 2 diabetes mellitus. J Assoc Physicians India. 2001;49:970-73.
19. Turner RC, Neil HAW, Stratton IM, Meanly SE, Mathews DR, Holman (the United Kingdom Prospective Diabetes Group). Risk factors for coronary artery disease in non insulin dependent diabetes mellitus (UKPDS 23). BMJ. 1998;3l6:823-28.
20. Bhu N, Coyal V, Mangal S, Goyal S. Blood lipids among 350 non insulin dependent diabetics subjects. SDMH J. l998;12:l67-74
21. Hardas SP, Bhatia SG, Doiphade DN. Lipid profile in diabetes mellitus. J Assoc Physicians India. 1991;39:99.
22. Kodali VRR, Venkatraman S, Madhavan R. Hyperlipidemia and complications of diabetes mellitus in the elderly. J Diab Assoc India. 199l;3l:5-9.
23. Meenu Walia, Agarwal AK, Shah P, Yadav R, Singh CP, Pushpa Yadav. Prevalence of coronary risk factors in Non-lnsulin dependent diabetes mellitus (type-2). J Assoc Physicians India. 1999;47:l05l-55.

	Source of support: Nil. Conflict of interest: Not Declared