Metabolic and anthropometric determinants of serum Lp(a) concentrations and Apo(a) polymorphism in a healthy Arab population.
BACKGROUND
Blood lipoprotein(a) Lp(a) concentrations are an important risk factor for atherosclerosis. The basis for this atherogenic property of Lp(a) and the factors that influence its cross-population levels, however, remain poorly understood.


OBJECTIVE
To investigate the relationship between serum Lp(a) and metabolic and anthropometric parameters in a healthy Kuwaiti population.


METHODS
Cross-sectional study.


METHODS
177 (72 male, 105 female) randomly recruited healthy Kuwait Arabs aged 17-60 y


METHODS
Metabolic parameters in serum: Lp(a), apo(a) phenotypes, lipids and lipoproteins, glucose and urate. Anthropometric parameters: body mass index (BMI) and waist:hip-ratio (WHR).


RESULTS
The distribution of Lp(a) concentrations was positively skewed (median 153 mg/l, range 0-1086). Women had higher concentrations-(194, 0-1086) than men (117, 0-779), P = 0.069. Lp(a) and insulin concentrations were significantly higher when the men and women were obese. In all subjects, there were significant correlations between Lp(a) and BMI (r = 0.23), total cholesterol (TC) (r = 0.17) and LDL (r = 0.20). Lp(a) correlated only with glucose in men (r = 0.28). In women it correlated with age (r = 0.20), BMI (r = 0.30), BP (r = 0.20), TC (r = 0.20) and LDL (r = 0.26). Multivariate analyses confirmed BMI and low-density lipoprotein (LDL) as the significant determinants of serum Lp(a). On apo (a) phenotyping, 114 (67%), 51 (30%) and 6 (4%) had single, double and null phenotypes respectively. The isoforms and their corresponding kringle IV repeat numbers were: F (14 repeats in 3%, mean Lp(a) 497 mg/l); S1 (19 repeats in 14%, mean 245 mg/l); S2 (23 repeats in 16%, mean 264 mg/l); S3 (27 repeats in 35%, mean 236 mg/l); and S4 (35 repeats in 28%, mean 235 mg/l).


CONCLUSIONS
The results from the Kuwaiti population studied suggest that: (1) serum Lp(a) concentrations and distribution are similar to the pattern in Caucasians and Asians but not African-Americans or Africans; (2) serum Lp(a) is variably influenced by BMI and LDL--the impact of either factor differs between the sexes; (3) there is a high frequency of the single-banded phenotype; (4) contrary to reports in some Caucasian and Asian populations, there is no simple relationship between kringle IV repeat numbers and plasma Lp(a) concentrations.
Akanji
A O
AO
Department of Pathology, Kuwait University Faculty of Medicine, Kuwait. abayomi@hsc.kuniv.edu.kw
al-Shayji
I A
IA
Kumar
P
P
D000293:Adolescent; D000328:Adult; D000886:Anthropometry; D001054:Apolipoproteins A / Q000235:genetics*; D003324:Coronary Artery Disease / Q000097:blood / Q000235:genetics*; D003430:Cross-Sectional Studies; D004734:Energy Metabolism / Q000235:genetics; D005260:Female; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics; D007730:Kuwait; D017270:Lipoprotein(a) / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000235:genetics*; D011110:Polymorphism, Genetic; D012737:Sex Factors; D044465:White People / Q000235:genetics
D001054:Apolipoproteins A; D017270:Lipoprotein(a)