A STUDY OF DYSLIPIDAEMIA AMONG PATIENTS WITH TYPE 2 DIABETES IN THE NORTHERN PROVINCE OF SRI LANKA

Results: The mean age of the study population was 56.5 years and there were 13 males (25.5%) and 38 females (74.5). Most common lipid abnormality demonstrated was low HDL (High-density lipoprotein) cholesterol, which was seen in 81.6% (n=31) of females and 69.2% (n=9) of males. In addition, 64.7% (n=33) patients had high LDL (Low density lipoprotein) cholesterol and 27.5% (n=14) of patients had high TG (Triglyceride) levels. 84.3% (n=43) of patients did fall into the high-risk group according to atherogenic index. Further, this study demonstrated a negative correlation between HDL and LDL cholesterol levels among the subjects.

Type 2 Diabetes Mellitus is a heterogeneous condition characterized by the presence of both impaired insulin secretion and insulin resistance.It is the commonest metabolic disorder affecting the people throughout the world.In 2010, approximately 285 million people had diabetes mellitus and more than 438 million people worldwide are expected to have diabetes by 2030.South Asians represent one-fifth of the world population, concentrated in a large geographic area of the Indian subcontinent where highest burden of diabetes is expected (1).

Multiple studies done on this South Asian
There is reasonable amount of data in related to the prevalence and pattern of lipid dyslipidemia among patients with diabetes in neighbouring countries of Indian subcontinent (8,9,10,11,12,13).However, there is very limited data available in Sri Lanka in this regard (14).The main objective of this study was to study the lipid abnormalities among patients with Type 2 Diabetes Mellitus, registered at Family Health Centre, Kondavil, Jaffna.population have demonstrated a 3-to 5-fold increase in the risk of cardiovascular disease (2,3,4,5,6) and they tend to develop it at a younger age when compared to other ethnic origins (7).
Diabetes, hypertension and dyslipidaemia are considered as the main traditional risk factors for cardiovascular disease and the co-existence these metabolic risk factors are well known.Dyslipidaemia plays a bigger role in the pathogenesis of cardiovascular disease in patients with diabetes and higher prevalence of dyslipidaemia among patients in South Indian origin may be the reason for higher prevalence of cardio-vascular disease among these patients.Family Health Centre, Kondavil, Jaffna.

Selection of patients:
After obtaining written informed consent, a total of 51 patients with Type 2 diabetes mellitus were recruited for the study.Patients with other diseases such as hypothyroidism, nephrotic syndrome, recent trauma or surgery that could alter lipid levels and the patients who were on lipid-lowering drugs within last 6 weeks were excluded from this study.

The study protocol and data collection:
The study protocol was reviewed and approved by ethical review committee, Faculty of Medicine, University of Jaffna.Data needed for this study (Age and sex) were collected according to the general and specific Laboratory analysis: Blood was collected and then centrifuged immediately to separate the plasma needed for lipid analysis.Plasma was kept at (-20) degree.Analysis of lipids was performed on the same day or the following day.Total cholesterol, triglyceride and HDLcholesterol were measured and LDLcholesterol was calculated according to the Friedewald formula (LDLcholesterol = Total cholesterol -HDL -triglyceride/5, in mg/dl)

Statistical
analysis: Statistical analysis was performed with a help of SPSS statistical software.volume (3 burette readings) of sodium thiosulfate using the following formula.
Considering the gender differences in cut-off values, HDL cholesterol levels of males and females were analysed separately.The study showed that 69.2% (9) of males and 81.6% (31) of females had low HDLcholesterol (Low HDL-cholesterol is defined as </= 40mg/dl in males and </= 50 mg/dl in females).

DISCUSSION
The atherogenic index was calculated using the triglyceride and the HDL-Cholesterol levels and it was classified as low risk, intermediate risk and high risk, when it falls below 0.1, between 0.1 and 0.24 and above 0.24 respectively.The majority (84.3%) of the study population was in the high-risk group.
There was a significant negative correlation between the HDL and the LDL cholesterol levels (Figure 1).However, the sample size was too small interpret the statistical significance and to draw conclusions regarding the relationship of these parameters.Cardiovascular disease accounts for more than 65% of the deaths in diabetes (15).The increased cardiovascular risk appears to be multifactorial.However, diabetes dyslipidaemia seems to play a significant role in the pathogenesis.

Mean (mg/dl) N-51 SD
The studies have shown that the prevalence of dyslipidaemia in the diabetes population is almost twice the figure compared to the general population (16).High plasma triglyceride concentrations, low HDL concentrations and elevation of small LDL cholesterol particle concentrations are characteristic of diabetes dyslipidaemia (9,17).The complex metabolic abnormalities related to obesity, insulin resistance, hyperinsulinism and poor glycaemic control are thought to be responsible for the lipid abnormalities seen in patients with diabetes (10,11).Hypertriglyceridaemia and low HDL are the commonest lipid abnormalities seen in patients with diabetes (8, 9, 10, 18), which was demonstrated even in our study population.
Hypertriglyceridemia and high LDL cholesterol levels are common lipid abnormalities seen among the patients with type 2 diabetes (9,17).
Our study demonstrated that 64.7% (68.4%, n=26 of females and 53.8%, n=7 of males) of study population had a LDL-Cholesterol of more than or equal to 100mg/dl.However, only 26.3% (n=10) of females and 30.8% (n=4) of males had high triglyceride level, which needs further evaluation with a bigger patient sample.
South Asians are well known to have more atherogenic lipid abnormalities (the ratio of total cholesterol (TC) to HDL, TG/HDL, and apo B/apo A1) compared to other ethnic groups (11,12) and these levels are highly correlated with the higher incidence of premature cardiovascular disease (13,14).The atherogenic index calculated from TG and HDL by using formula Log10 TG/HDL showed that thirtythree (86.8%) females and ten males (76.9%) did fall into the high-risk group and accounting for 84.3% of our study population with high risk for atherosclerosis.Previous studies also have demonstrated almost similar trend among the Sri Lankan patients with type 2 diabetes mellitus (14).
According to the statistical calculations, the study required a sample of 339 patients and the smaller sample size was a major limitation of this study.Although we were unable to draw firm conclusions, it appeared to be a reasonable preliminary study and an area that needs to be further studied.Sri Lanka Journal of Diabetes, Endocrinology and Metabolism

LIMITATIONS
According to the statistical calculation, the study required 339 patients and the smaller sample size was a major limitation of this study.Although we were unable to draw firm conclusions, it appeared to be a reasonable preliminary study and an area that needs to be further studied.

CONCLUSIONS
Low HDL cholesterol followed by hypertriglyceridaemia is the commonest lipid abnormality found in Sri Lankan patients with Type 2 diabetes.These patients also have a high atherogenic index with a higher susceptibility cardiovascular disease.This preliminary study highlights the importance of further research on this area to explore the lipid pattern among the Sri Lankan type 2 diabetes mellitus population.

ACKNOWLEDGEMENT
I express my sincere thanks to the staff at family Health Centre, Kondavil, Dr.Dinesh Coonghe, Lecturer in Community medicine for the statistical analysis and all the patients participated this study.

Figure 1 :
Figure 1: Figure shows the correlation between LDL-Cholesterol and HDL-Cholesterol.