Dear Editor,
Although the burden of cardiovascular disease (CVD) states is stabilizing in high-income countries, in low-to-middle-income countries it continues to rise.1 Lifestyle, environmental and genetic factors play an important role in coronary heart disease (CHD) development.2 Previous studies have shown that blacks have one of the highest rates of coronary artery disease in the world.3 However, Caucasians generally have higher mean total cholesterol (TC) concentrations than do populations of Asian or African origin.4
Hospital based case control study was design to study lipid profile in coronary heart disease patients in Sudan. Among the total population studied (104 cases and 105 controls) 53.1% were male, 45% were from Northern Sudan and 72.7% were residing in urban areas. About 26.8% of the most infected age group was less than 40 years, 22% had strong family history of CHD, 42.6% had hypertension and 41.6% had diabetes mellitus. Smoking and alcohol consumption are very low among population represent 18.2% and 5.3%, respectively.
Lipid profiles were analyzed using standard enzymatic methods on a MINDRAY BS-200 analyzer (MINDRAY, Shenzhen, China). General linear model and correlation between serum biochemical profiles were performed using SPSS15.0. The results showed that Sudanese patients had significantly lower TC and LDL-C levels and non-significantly lower triglycerides, HDL-C and VLDL levels compared with controls (Table 1). Age has a significant (p < 0.05) effect on LDL-C, while sex, race or ethnic, family history, residence, smoking, alcohol consumption has no significant (p < 0.05) effect on lipid profiles. Hypertension has no significant (p < 0.05) effect on lipid profiles, while diabetes mellitus has a significant (p < 0.05) effect on total cholesterol, and LDL-C (data not shown). Among patients TC was significantly (p < 0.05) and positively correlated with LDL and HDL, while VLDL was positively correlated with triglycerides. In contrast, triglycerides and VLDL were negatively correlated with LDL and HDL similarly VLDL was positively correlated with triglycerides (Table 2). In control group total cholesterol was significantly (p < 0.05) and positively correlated with triglycerides, LDL and VLDL. Triglyceride was negatively correlated with HDL and positively with VLDL and HDL was negatively correlated with LDL and VLDL (Table 2). Blacks had nominally higher adjusted HDL-C levels, and significantly lower triglyceride levels than whites.5 African ancestry was significantly associated with decreased total cholesterol, LDL-C and triglycerides.6 These observed associations between African ancestry and several lipid traits are consistent with the general tendency of individuals of African descent to have healthier lipid profiles compared to European–Americans.6 Our results confirm a high prevalence of conventional risk factors of coronary heart disease as well as the association between these factors with lipid profiles in Sudanese population. However, sample size used was very small of the general population, other studies using large sample size were needed to provide more accuracy and predictive value of coronary heart disease risk factors.
Table 1.
Baseline characteristics and risk factors for coronary heart disease in cases and controls subjects.
| Traits | Over all (n = 209) | Case (n = 104) | Control (n = 105) | p Value |
|---|---|---|---|---|
| Age (yrs) | ||||
| <40 (%) | 26.8 | 5.8 | 47.6 | 0 |
| 41–50 (%) | 18.7 | 16.3 | 21.0 | 0.423 |
| 51–60 (%) | 23.9 | 30.8 | 17.1 | 0.048 |
| 61–70 (%) | 19.1 | 29.8 | 8.6 | 0.001 |
| >70 (%) | 11.5 | 17.3 | 5.7 | 0.014 |
| Ethnic | ||||
| Northern Sudan (%) | 45.0 | 58.7 | 31.4 | 0.004 |
| Western Sudan (%) | 34.0 | 19.2 | 48.6 | 0.000 |
| Eastern Sudan (%) | 2.4 | 2.9 | 1.9 | 0.655 |
| Southern Sudan (%) | 1.4 | 3.8 | 2.9 | 0.705 |
| Central Sudan (%) | 17.2 | 15.4 | 15.2 | 1 |
| Gender | ||||
| Male (%) | 53.1 | 56.7 | 49.5 | 0.506 |
| Female (%) | 46.9 | 43.3 | 50.5 | 0.419 |
| Residence | ||||
| Urban (%) | 72.7 | 73.1 | 72.4 | 1 |
| Rural (%) | 27.3 | 26.9 | 27.6 | 0.895 |
| Hypertension (%) | 42.6 | 56.7 | 28.6 | 0.002 |
| Diabetes (%) | 41.6 | 40.4 | 42.9 | 0.748 |
| Family history (%) | 22.0 | 32.7 | 11.4 | 0.001 |
| Smoking (%) | 18.2 | 22.1 | 14.3 | 0.196 |
| Alcohol (%) | 5.3 | 7.7 | 2.9 | 0.132 |
| TC mg/dL (X ± SE) | 158.82 ± 9.75 | 220.90 ± 8.94 | 0.000 | |
| TG mg/dL (X ± SE) | 243.52 ± 17.23 | 250.75 ± 15.80 | 0.749 | |
| LDL mg/dL (X ± SE) | 63.29 ± 8.56 | 132.22 ± 7.85 | 0.000 | |
| HDL mg/dL (X ± SE) | 45.91 ± 3.08 | 46.23 ± 2.82 | 0.851 | |
| VLDL mg/dL (X ± SE) | 48.78 ± 3.39 | 51.19 ± 3.11 | 0.603 | |
TC: total cholesterol mg/dL, TG: triglyceride mg/dL, LDL: low density lipoprotein mg/dL, HDL: high density lipoprotein mg/dL, VLDL: very low density lipoprotein mg/dL, CI: 95% confidence interval.
No. of samples for lipid profile for cases and controls were 65 and 78, respectively.
Table 2.
Correlation coefficient matrixes of cholesterol, triglycerides, and lipoprotein indices in case and control population.
| Traits | TC mg/dL | TG mg/dL | LDL mg/dL | HDL mg/dL | VLDL mg/dL |
|---|---|---|---|---|---|
| TC mg/dL | 1 | 0.214 | 0.719a | 0.403a | 0.218 |
| TG mg/dL | 0.516a | 1 | −0.070 | −0.153 | 0.999a |
| LDL mg/dL | 0.747a | 0.168 | 1 | 0.142 | −0.065 |
| HDL mg/dL | 0.189 | −0.100 | −0.039 | 1 | −0.153 |
| VLDL mg/dL | 0.520a | 0.987a | 0.174 | −0.103 | 1 |
Cases were above the diagonal, and controls were below the diagonal.
Correlation is significant at the 0.01 level (2-tailed).
Acknowledgments
This study was supported by a grant from the Ministry of Higher Education, Sudan.
References
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