Dyslipidemia and associated factors

Dyslipidemia and associated factors

Dyslipidemias are the major risk factor for various diseases –including, cancer, obesity, diabetes, pancreatitis, and cardiovascular diseases. Population surveillance is very crucial in monitoring risk factors for various diseases. However, in Pakistan there is a paucity of population-level data on incidence and prevalence of dyslipidemias. Most of the previous works were focused on studying the prevalence of dyslipidemias among patients of coronary heart diseases. However, the incidence and prevalence of dyslipidemia among general population has not been investigated in detail. In one of our ongoing research projects we are studying plasma lipid trends and abnormalities in Pakistani population. We are studying the environmental and genetic factors underlying dyslipidemias in the respective population. In the initial phase of the project, the prevalence and types of dyslipidemia were assessed in the population-based sample. These initial analyses revealed that the prevalence of dyslipidemias was higher in the male-population. Also, dyslipidemias were more common among the urban-participants. In general, the prevalence of plasma lipid abnormalities was very high in the recruited study-group –with 63% of the participants displaying irregularity in at least one major lipid-fraction total cholesterol (TC), low density lipoproteins (LDL), high density lipoproteins (HDL) or triglycerides (TG). Moreover, the most prevalent form of dyslipidemia was isolated low-HDL level (17.22%). This coincides with previous observations that also indicated higher prevalence of low-HDL levels in Asians in comparison to non-Asians.

Prevalence different of isolated- and mixed-dyslipidemias in the study population. (a) Venn-Diagram displays overlaps between prevalence of high TC, LDL-C, TG and low HDL-C levels in the study population

Association between dyslipidemia and different anthropometric indices

We have also studied in detail the association between dyslipidemia and different anthropometric indices was examined. Detailed analyses were performed to determine the significance of various anthropometric indices in assessment of incidence, type and severity of dyslipidemia. Classical body indices –body mass index (BMI), waist-circumference (WC), resting metabolic rate (RMR), body fat percentage, total body fat mass, fasting glucose– and newly described body indices –a body shape index (ABSI) and body roundness index (BRI)– were evaluated in this context. Several body indices including the classical indicators of obesity displayed significant positive correlation with LDL, TG and serum cholesterol levels, whereas negative correlation with serum HDL levels. It was observed that the capacity of BRI to predict dyslipidemia was comparable but not superior to the classical indicators of obesity –including BMI, body fat percentage and waist circumference– whereas ABSI could not detect presence or absence of dyslipidemia. Further, analyses revealed that several anthropometric/metabolic indices display increased predictive capabilities to detect hypertriglyceridemia in comparison to detect any other form of plasma lipid disorders.

 

A Mouse Model of Diet-Induced Obesity and Metabolic Disorders

Previous works suggest that dietary habits may also contribute to high incidence of dyslipidemia in South Asian population. In the recent years, the cafeteria diet-fed rats/mice have emerged as pertinent animal models for studying human obesity, dyslipidemia and metabolic disorders. In one of our recent projects the findings of the previous works were extended and mice were maintained on different types of cafeteria diets: high-sugar/high-fat-cafeteria (HSHF-CAF)-diet or low-sugar/low-fat-cafeteria (LSLF-CAF)-diet. The control group was fed on standard-chow. The diet-intake, metabolic fates and behavioral changes in these mice were monitored. Despite the fact that the animals consumed similar amounts of food the distinctive macronutrients composition of the experimental diets resulted in differential macronutrient-intake in the three diet-groups throughout the course of the study. These differences resulted in increased weight-gain, adiposity and adipocyte hypertrophy in the mice on CAF-diets when compared to the chow-fed mice. However, despite the obvious difference in the nutritive values of HSHF-CAF and LSLF-CAF diets no significant metabolic differences were observed between the mice consuming these diets. Additionally, no significant differences was observed in organ-to-body weight ratios, plasma lipid profiles, lipid deposition in metabolic tissues (liver and adipose tissue), and ectopic fat storage in heart and kidney, among the three diet groups. Further, studies are required to better understand the effects of diet-intake on development of dyslipidemia.

Figure summarizes the experimental set-up and data collection points. During a 5-week dietary intervention period, BALB/c mice were studied in three groups: high-sugar/high–fat cafeteria (HSHF-CAF) diet, low-sugar/low–fat cafeteria (LSLF-CAF) diet, or standard-chow diet. All groups included equal number of animals. Symbols: n, m and f denote total number of mice, total number of male mice, and total number of female mice respectively

Cell size of retroperitoneal adipocytes from mice maintained on standard-chow-, HSHF-CAF-, or LSLF-CAF-diet. Values are expressed as the mean ± SD (n = 30-40). Data were analyzed using Student’s t-test. *Significant difference comparing standard-chow-diet with HSHF-CAF-diet or LSLF-CAF-diet (P <0.05). Abbreviations: HSHF-CAF, high-sugar/high–fat cafeteria; LSLF-CAF, low-sugar/low-fat cafeteria.

Related Publications from Our Lab

  1. Zaid M, Ameer F, Munir R, Rashid R, Farooq N, Hasnain S, Zaidi N: Anthropometric and metabolic indices in assessment of type and severity of dyslipidemia. J PhysiolAnthropol 2017, 36:19.
  2. Zaid M, Hasnain S: Plasma lipid abnormalities in Pakistani population: Trends, associated factors, and clinical implications

 

Related Theses from Our Lab

Level Student’s Name Thesis Title Year
PhD Muhammad Zaid Genetic, metabolic and anthropometric variations associated with aberrant plasma lipid profile Submitted in 2018
 

M.Phil.

 

Mehar-un-NisaSaleem Studying the association of various demographics, metabolic and clinical factors with a body shape index (ABSI) 2017-18
Undergraduate  AmnaSaleem Studying the association between body roundness index (BRI) and plasma lipid profiles 2017-18