Biomedical subjects

A O Akanji

Publications and source records attributed to A O Akanji.

At least 19 recordsLinked to original sources

PubMed2006

Prostate cancer risk: the significance of differences in age related changes in serum conjugated and unconjugated steroid hormone concentrations between Arab and Caucasian men.

INTRODUCTION: Factors responsible for the low incidence of clinical prostate cancer (3-8/100,000 men/year) in the Arab population remain unclear, but may be related to changes in steroid hormone metabolism. We compared the levels of serum conjugated and unconjugated steroids between Arab and Caucasian populations, to determine if these can provide a rational explanation for differences in incidence of prostate cancer between the two populations. PATIENTS/METHOD: Venous blood samples were obtained from 329 unselected apparently healthy indigenous Arab men (Kuwaitis and Omanis) aged 15-80 years. Samples were also obtained from similar Arab men with newly diagnosed prostate cancer or benign prostatic hyperplasia (BPH). The samples were taken between 8:00 am and 12:00 noon. Serum levels of total testosterone, (TT), sex hormone binding globulin (SHBG), free androgen index (FAI); adrenal C19-steroids, dehydroepiandrosterone sulphate (DHEAS) and androstenedione (ADT) were determined using Immulite kits (Diagnostic Systems Laboratories Inc, Webster Texas, USA). The results obtained in Arab men were compared with those reported for similarly aged Chinese, German and White USA men. RESULTS: In all four ethnic groups, median TT and FAI declined with age, while SHBG increased with age. However, the mean TT and SHBG was significantly lower (p < 0.01) and the FAI significantly higher in Arab men (p < 0.01) compared to German men only in 21-30 years age group. In the other age groups the levels of TT and SHBG were higher in the Germans but the differences were not statistically significant. In all the racial groups serum levels of DHEAS and ADT reached a peak by about 20 years of life, and then declined progressively. The mean DHEAS in American Caucasians aged 20-29 years was 11.4 micromol/l compared to 6.22 micromol/l in the Arabs (p < 0.001). The mean DHEAS in USA Caucasians aged 70-79 years was 2.5 micromol/l compared to 1.8 micromol/l (p < 0.03) in the Arabs. There was no significant difference in mean serum levels of DHEAS between German and USA men. Similarly, there was no significant difference in the level of the hormones between Arab and Chinese men. Arab men with newly diagnosed prostate cancer had high serum TT, SHBG and DHEAS compared to those without the disease. CONCLUSIONS: The mean TT and SHBG was significantly lower in Arab men compared to Caucasian men especially in early adulthood. Caucasians have significantly higher serum levels of the precursor androgens DHEAS and ADT especially in early adulthood compared to Arab men. These observations of low circulating androgens and their adrenal precursors in Arab men may partially account for the decreased risk for prostate cancer among Arab men.

Adolescent↗

PubMed2005

Putative role of serum insulin-like growth factor-1 (IGF-1) and IGF binding protein-3 (IGFBP-3) levels in the development of prostate cancer in Arab men.

INTRODUCTION: The incidence of clinical prostate cancer in the Arab population is among the lowest in the world. High serum IGF-1 level has been implicated as a possible risk factor for the development of prostate cancer in Caucasians. The purpose of this study was to determine serum IGF-1 and IGFBP-3 levels in healthy Arab men and in Arab men with newly diagnosed benign prostatic hyperplasia (BPH) and prostate cancer, and to compare these values with values reported in Caucasians. PATIENTS AND METHODS: Subjects were recruited in two groups: (a) indigenous, healthy Arab men aged 15-90 y (n = 383); (b) Arab men with newly diagnosed prostate cancer (n = 30) or BPH (n = 40). Blood was obtained from fasting patients and volunteers, between 8:00 a.m. and 12:00 noon. The serum concentrations of IGF-1 and IGFBP-3 were determined using Immunoradiometric assay (IRMA) kits. RESULTS: As in Caucasians, serum IGF-1 and IGFBP-3 levels declined with age in Arab men. The mean +/- s.d. of serum IGF-1 levels in healthy Arab men in the age group 15-20, 51-60, 61-70 y were lower (376.2 +/- 153.2, 134.9 +/- 105.7 and 89.6 +/- 48.4 ng/ml, respectively), compared to values reported for similarly aged Caucasians. Arab men with newly diagnosed prostate cancer had significantly higher serum IGF-1 level (P < 0.01) and lower IGFBP-3 levels (P < 0.01) compared to age-matched Arabs without the disease. CONCLUSIONS: Arab men have lower serum IGF-1 levels compared to Caucasians and this may be an important factor in the explanation of the low incidence of prostate cancer in the Arab population.

Adolescent↗

PubMed2004

HLA determinants of susceptibility to multiple sclerosis in an Arabian Gulf population.

BACKGROUND: An association between HLA antigens and susceptibility to multiple sclerosis (MS) has been established, especially in Caucasian populations. Such associations have not been as clearly defined in many Arab populations, where even the frequencies of specific HLA antigens remain unclear OBJECTIVE: The study was designed to (i) investigate the frequencies of HLA Class I and II antigens in Kuwaiti Arabs with MS, and; (ii) assess possible inter-relationships between HLA Class II antigens and such clinical phenotypic variables in MS as age at onset, gender, disease subtype and scale of disability. SUBJECTS AND METHODS: HLA Class I (A, B, C) and Class II (DR, DQ) antigens' tissue-typing was performed by the standard complement-dependent microlymphocytotoxicity technique in two groups of age- and sex-matched Kuwaiti subjects: (i) 67 patients with definite MS (48 relapsing remitting, 19 relapsing-progressive) and (ii) 145 unrelated healthy controls. The frequencies of specific HLA types were then compared between patients with controls, and in the former, related to specified clinical parameters. RESULTS: The frequencies for the Class I antigens: A9, A10, A19, A33, B5 and CW4 appeared higher with the presence of MS, although the numbers of positive subjects were rather low. For the Class II antigens, frequencies of DR4, DQ5, DQ6, DQ7 and DQ8 were increased while those for DR6 and DR1 were decreased in the patients with MS. HLA types DR15 and DR4 were present at higher frequencies in patients with a younger age at disease onset; DR15 also appeared more frequent in the female patients. CONCLUSION: There is a trend towards an association between HLA Class II antigens (DR4, DQ6, DQ7 and DQ8) and MS in Kuwaiti subjects. Additionally, it appeared that DR4 and DR15 were more frequent in females and those with an early onset of the disease. These patterns of HLA Class II determinants of susceptibility to MS differ from reports in some other populations, and may reflect the recognized variability in genetic influence on HLA and disease expression.

Adolescent↗

PubMed2002

Associations of plasma homocysteine concentration in subjects with type 2 diabetes mellitus.

We investigated the potential relationship between hyperhomocysteinemia and the presence of coronary heart disease (CHD) and chronic complications in a consecutive series of 358 (156 men) Kuwaiti type 2 diabetic subjects. The median (2.5(th), 97.5(th) percentiles) fasting plasma concentration of total homocysteine (tHcy) in the patients was 10.2 (5.4, 19.1) micromol/l. Fasting tHcy concentration was significantly (p<0.001) higher among men [11.3 (7.1, 24.6) micromol/l] compared to women [8.8 (5.3, 16.3) micromol/l]. Of the 57 patients with a history of CHD and/or electrocardiographic (ECG) evidence of CHD, 9 (16%) had hyperhomocysteinemia (tHcy > or =15 micromol/l) compared to 8.3% (25 of 301) of patients without evidence of CHD. In univariate analysis, plasma tHcy concentration was significantly (p<0.01) higher in those diabetic subjects with history of CHD and/or abnormal ECG. Although hyperhomocysteinemia was more common in patients with microalbuminuria (15%) compared to patients with normoalbuminuria (12%), there was no significant association between hyperhomocysteinemia and the degree of albuminuria. After controlling for age and sex, multiple regression analyses showed significant associations of plasma tHcy concentration with glycated hemoglobin (p<0.05), plasma concentrations of creatinine (p<0.001) and apolipoprotein-B (p<0.05), but not with smoking, neuropathy or retinopathy. It seems that the association of hyperhomocysteinemia with diabetic microvascular complications is mediated by the confounding effect of other factors like age, sex and plasma creatinine concentration. In conclusion, we have found a univariate association between hyperhomocysteinemia and CHD but not with microalbuminuria, neuropathy and retinopathy. Although routine estimation of plasma homocysteine may be useful, the association with cardiovascular disease or microvascular complications in patients with type 2 DM deserves prospective studies.

Albuminuria↗

PubMed2002

Association of C-reactive protein with coronary heart disease risk factors in patients with type 2 diabetes mellitus.

The assessment of markers of systemic inflammation, such as C-reactive protein (CRP) and interleukin 6 (IL6), could be used to identify persons at high risk of coronary heart disease (CHD). This study evaluates the relationship of CRP and IL6 with CHD risk factors in patients with type 2 diabetes mellitus (DM) with CHD and age and sex matched type 2 DM controls without CHD. CRP, IL-6, total plasma homocysteine (tHcy), lipoprotein (a) [Lp(a)] and sialic acid (SA) were determined in 55 type 2 diabetic patients with CHD and 51 age- and sex-matched type 2 diabetic controls without CHD. Multivariate and logistic regression analyses were used to relate these markers with CHD risk factors. CRP (P=0.02) and tHcy (P=0.03) were significantly higher in patients with CHD compared with the control group even after correction for age and sex. IL6, Lp(a), SA and lipid parameters were not significantly different between the two groups of patients. After adjustment for potential confounders, the odds ratio (OR) for elevated CRP was 2.00 (95% confidence interval [CI], 1.12-3.58) (P=0.02) but the OR for IL6 was 3.41 95% CI, 0.70-17.17 (P=0.14). Partial correlation analyses of CRP and IL6 with other variables showed significant correlation of CRP with tHcy, and SA in patients with CHD only. Our results support the inclusion of CRP (high-sensitivity assay), in the risk assessment of diabetic subjects.

Apolipoproteins↗

PubMed2001

Effect of insulin on transport kinetics of alpha-aminoisobutyric acid in the perfused human placental lobule in vitro.

BACKGROUND: The limited data available on the role of insulin on maternal-fetal transport of amino acids prompted us to undertake this study. METHODS: Transport kinetics of a model amino acid, alpha-aminoisobutyric acid (AIB) was investigated in perfusion of isolated human placental lobules in vitro in non steady-state conditions and the effect of therapeutic dose of insulin was assessed in parallel series of perfusions. National Culture and Tissue Collection medium diluted with Earle's buffered salt solution was used as the perfusate and tritiated water was used as the reference marker for comparison. RESULTS: In five successful perfusions with insulin, differential transport rate indices of AIB for 10, 25, 50, 75 and 90% of efflux fractions in the fetal venous outflow averaged 0.76, 1.03, 1.02, 1.09, 1.04 and 1.03 times those of reference values, respectively. The indices differed significantly than in controls for 10, 25 and 50% efflux fractions, but not in the case of 75 and 90% efflux values. The AIB transport fraction (TF), expressed as percentage of injected maternal dose, averaged 29.4 +/- 5.4% and 38.7 +/- 6.2% of the corresponding reference marker value in control and insulin series, respectively. With regards to the pharmacokinetic transport parameters, the absorption and elimination rates of the amino acid were significantly higher in the study group than in the control. CONCLUSION: We conclude that insulin, in physiological and therapeutic doses, stimulates maternal-fetal AIB transport in vitro, in the perfused human placental lobule.

Aminoisobutyric Acids↗

PubMed2000

Relation of serum total sialic acid concentrations with diabetic complications and cardiovascular risk factors in Kuwaiti Type 2 diabetic patients.

Serum total sialic acid is a marker of the acute phase response. Elevated levels have also been associated with cardiovascular disease in the general Caucasian population and especially in Type 2 diabetic subjects. The purpose of this study was to estimate serum total sialic acid concentrations among Kuwaiti Type 2 diabetic subjects and to investigate its association with macro and microvascular diabetes-related complications in that population. Serum total sialic acid levels were estimated by an enzymatic spectro-photometric assay in two groups of subjects: (i) 358 Kuwaiti Type 2 diabetics (156 men and 202 women) referred for their annual evaluation to the specialised diabetic clinic at the main university teaching hospital in Kuwait, and (ii) 47 healthy age and sex matched non-diabetic Kuwaiti control population (13 men and 34 women). Serum sialic acid levels were significantly higher (P<0.001) among the diabetic patients (mean+/-S.D.) (81.2+/-13.2 mg/dl) compared to the non-diabetic controls (66.9+/-11.0 mg/dl). Kuwaiti diabetic women had significantly higher concentrations compared to diabetic men (85.2+/-12.1 vs. 75.9+/-13.0 mg/dl, P<0.001). Among the controls there was no significant gender difference in sialic acid levels of women, (68.3+/-11.6 mg/dl) versus men (63.2+/-8.2 mg/dl). The gender difference in the diabetic patients was unrelated to the degree of obesity. Significant correlations were found between serum total sialic acid concentrations and such cardiovascular risk factors as plasma levels of apolipoprotein B, low density lipoprotein cholesterol, triglycerides and uric acid in the diabetic subjects. Furthermore, there was a significant elevation in serum total sialic acid concentrations with increasing urinary albumin excretion, P<0.001, but not with retinopathy or neuropathy.

Albuminuria↗

PubMed2000

Homocysteine and endogenous markers of renal function in type 2 diabetic patients without coronary heart disease.

The aim of this study was to assess parameters of renal function and other determinants of plasma homocysteine in type 2 diabetic patients without coronary heart disease (CHD). Fasting plasma homocysteine, serum cystatin C and serum creatinine were determined in 183 (75 men, 108 women) Type 2 diabetic patients without clinical evidence of CHD. Creatinine clearance was calculated and parameters such as blood pressure, body mass index (BMI), and glycated haemoglobin (HbA(1c)) were assessed. The urine albumin:creatinine ratio was used to classify patients as normo-, micro- or macroalbuminuric. One hundred and ten patients were normoalbuminuric, 67 patients were microalbuminuric and six patients were macroalbuminuric. There was no statistically significant difference in plasma homocysteine concentration between patients with normoalbuminuria and microalbuminuria. There was a trend towards increasing plasma homocysteine with decreasing glomerular filtration rate (GFR) (r=-0.46; P<0.0001). There was statistically significant correlation between plasma homocysteine and age (r=0.37), serum cystatin C (r=0.47), and serum creatinine (r=0.56). Plasma homocysteine concentration was significantly higher in patients with BMI<30 kg/m(2) and showed significant inverse correlation with weight (r=-0.16; P=0.03) and body mass index (r=-0.24; P=0.001). Homocysteine and serum creatinine were significantly higher in males than females and higher in smokers than non smokers but was not associated with glycemic control and duration of diabetes. In conclusion, elevated homocysteine concentration in patients with type 2 DM without CHD is related to age, gender, smoking, BMI and GFR. Follow up studies will provide further information on the association between hyperhomocysteinemia and the development of cardiovascular disease.

Albuminuria↗

PubMed2000

Beneficial changes in serum apo A-1 and its ratio to apo B and HDL in stable hyperlipidaemic subjects after Ramadan fasting in Kuwait.

BACKGROUND: In patients with metabolic and nutritional disorders such as diabetes and hyperlipidaemia, where strict compliance to advice on timing and composition of food intake is important, the prolonged daylight fasting during the month of Ramadan could produce undesirable biochemical consequences. AIM: The study aimed to compare pre- and post-Ramadan lipid and lipoprotein profiles in stable Kuwaiti hyperlipidaemic subjects attending a Lipid Clinic. SUBJECTS AND METHODS: The study population comprised 64 adult Kuwaitis (33 M, 31 F) who had been attending a Lipid Clinic for at least 12 months and were considered stable, without any acute systemic illness. At each clinic visit, the following parameters were measured: weight, total cholesterol (TC), triglycerides (TG), HDL, LDL, apo A-1, apo B, glucose and uric acid. These biochemical parameters were measured by routine automated analyzer techniques. The pre-Ramadan values comprised the means of two measurements taken at about 3 month and 1 month before commencement of Ramadan. Post-Ramadan values were obtained within 1 month of the end of the Ramadan fast. The parameters so obtained were compared in the whole group, and then according to gender, glycaemic status and modality of treatment (diet alone or with a fibrate or statin). RESULTS AND DISCUSSION: In the nondiabetic subjects, apo A-1 and apo A-1/apo B and apo A-1/HDL ratios were increased post-Ramadan (P<0.001). Weight did not change and the other lipid parameters-TC, TG, LDL, apo B-did not worsen. These observations, more consistent in the men than in the women, and in subjects treated with a fibrate or a statin rather than on diet alone, indicate a favorable coronary heart disease (CHD) risk profile. In the diabetic patients, these changes in the apo A-1 level and its ratio to HDL and apo B were also present, but TC and apo B levels increased, the latter significantly (P<0.05). These divergent effects in diabetic patients could variably influence CHD risk liability. Serum uric acid levels were also simultaneously reduced post-Ramadan in the non-diabetic subjects and those on statin treatment. CONCLUSION: When pre- and post-Ramadan lipid and lipoprotein profiles were compared in stable hyperlipidaemic subjects attending a Lipid Clinic in Kuwait, the most consistent changes post-Ramadan were increased levels of apo A-1 and apo A-1/apo B and apo A-1/HDL ratios and reduced uric acid levels. Body weight remained essentially unchanged and the other lipoprotein and lipid parameters were not worsened. These results suggest that Ramadan fasting in hyperlipidaemic subjects might favorably influence CHD risk.

Adult↗

PubMed2000

Apo(a) isoforms do not predict risk for coronary heart disease in a Gulf Arab population.

It is well recognized that blood lipoprotein A [Lp(a)] levels constitute an important risk factor for atherosclerotic vascular disease. In some populations, mainly Caucasian, Lp(a) levels and coronary heart disease (CHD) risk are determined by the pattern of apolipoprotein a [apo(a)] polymorphism. It is currently unclear if these observations apply to other populations and ethnic groups. The aim of the current study is to determine to what extent known apo(a) polymorphisms associate with development of CHD in a Kuwaiti Arab population. Serum Lp(a) levels were measured by enzyme-linked immunosorbent assay and apo(a) isoforms determined by a high-resolution sodium dodecyl sulphate/agarose gel electrophoresis with immunoblotting in two groups of Kuwaiti subjects: healthy controls (n = 140) and subjects with CHD (n = 140). Blood lipids and anthropometric parameters were also determined in these subjects by standard methods. Serum Lp(a) levels were greater in those with CHD than in those in the healthy group (P < 0.001). There was no consistent trend in the pattern of serum Lp(a) levels found with specific apo(a) isoforms in either group of subjects. There was, therefore, no simple relationship between the isoform pattern (and number of kringle-IV repeats) and serum Lp(a) concentration, unlike in certain other populations. Additionally, almost identical proportions of subjects in either group had single-banded (homozygous, approximately 70%), double-banded (heterozygous, approximately 23%) and no-band (null, approximately 7%) phenotypes. The distribution of the five identified isoforms (F, S1, S2, S3 and S4) also was almost identical for both groups of subjects, whether homozygous or heterozygous, and whether classified into fast-moving (F, S1 and S2) or slow-moving (S3 and S4) isoforms. We conclude that the frequency and pattern of distribution of apo(a) phenotypes did not differ significantly between healthy control Kuwaiti Arab subjects and those with CHD. It is thus unlikely that an individual's apo(a) phenotype can predict both serum Lp(a) level and risk for CHD, irrespective of race and/or ethnic grouping.

Adolescent↗

PubMed1999

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. OBJECTIVES: To investigate the relationship between serum Lp(a) and metabolic and anthropometric parameters in a healthy Kuwaiti population. DESIGN: Cross-sectional study. SUBJECTS: 177 (72 male, 105 female) randomly recruited healthy Kuwait Arabs aged 17-60 y MEASUREMENTS: 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). DISCUSSION AND CONCLUSION: 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.

Adolescent↗

PubMed1998

The relationships between insulin and plasminogen activator inhibitor 1 levels: assessment in groups of subjects with dyslipidaemia and hypertension.

Elevated plasminogen activator inhibitor-1 (PAI-1) levels have been described in some populations to associate with hyperinsulinaemia in the metabolic syndrome which predisposes to coronary heart disease (CHD). This association, if consistently present, could provide more evidence for a synergistic role for insulin resistance and altered fibrinolysis in the pathogenesis of CHD. To test the hypothesis further therefore, we explored the relationships between the fasting levels of insulin and PAI-1 and lipids in groups of non-diabetic Arab subjects classified as: A: normolipidaemic (n = 148); B: hyperlipidaemic: (n = 99), subdivided into - C: normotensive (n = 71) and D: hypertensive (n = 28); and E: patients with CHD (n = 12). In Group A, fasting insulin (FI) was 7.2+/-(SD) 3.4 mU/l, PAI-1 30.6+/-9.7 ng/ml, both levels significantly lower (P < 0.05) than in Group B as a whole (FI 9.7+/-5.2, PAI-1 36.9+/-10.6), or as normotensive Group C (FI 9.4+/-5.4, PAI-1 36.7+/-10.3) or hypertensive Group D (FI 10.9+/-4.8, PAI-1 37.2+/-11.5). These values were highest in the hyperlipidaemic hypertensive Group D. There were no significant differences relative to the hyperlipidaemic phenotype of predominant hypercholesterolaemia, hypertriglyceridaemia or mixed hyperlipidaemia. PAI-1 (34.7+/-13.8) and FI (7.0+/-2.4) levels in Group E with CHD were similar to those of Group A but lower than values seen in Groups B, C and D. Consistent positive correlations (r = 0.32-0.41, P <0.01) were demonstrable in all the groups between PAI-1 and triglycerides levels. There were also significant correlations between insulin and PAI-1 (r = 0.20, P<0.1) in all the subjects (grouped as a whole, n = 259) and in normolipidaemic Group A (r = 0.29, P < 0.01) but not in any of the hyperlipidaemic groups or in patients with CHD. This study therefore suggests that levels of insulin and PAI-1 are increased in hyperlipidaemic subjects, particularly when also hypertensive. The further observation of significant correlations between insulin and PAI-1 levels only in normolipidaemic subjects and not those who were hyperlipidaemic or with CHD is at variance with observations in Caucasians in whom strong positive correlations between insulin and PAI-1 had suggested that elevated PAI-1 levels should constitute one more component of the metabolic syndrome which strongly predisposes to CHD. Whether this is a racial variation or an artifact of the insulin/PAI-1 assay methodology is unclear and deserves further study.

Adolescent↗

PubMed1998

Direct method for the measurement of low-density lipoprotein cholesterol levels in patients with chronic renal disease: a comparative assessment.

BACKGROUND/AIM: This study was performed to comparatively evaluate the results obtained for low-density lipoprotein (LDL) cholesterol concentrations by either a newly described direct method or the Friedewald equation in subjects with and without chronic renal disease. METHODS: Fasting plasma was obtained from a total of 169 subjects, 105 with normal renal function (including 53 hyperlipidaemic) and 64 with chronic renal disease (nephrotic syndrome and/or chronic renal failure; including 40 hyperlipidaemic patients), and analyzed for LDL cholesterol using the Friedewald equation and a direct LDL assay method. RESULTS: The Friedewald equation and the direct LDL cholesterol assay correlated well with each other (r = 0.79-0.90 in all subjects with plasma triglyceride, TG, levels greater than or less than 4.0 mmol/l and with and without chronic renal disease and/or hyperlipidaemia, all p < 0.0001). The values for LDL cholesterol, however, tended to be higher with the direct measurement. This mean difference was trivial in hyperlipidaemic subjects with (8.5%) and without (7.1%) normal renal function (both p < 0.05), but could be clinically significant in those with TG >4.0 mmol/l (mean difference 18%, p < 0.001). Indeed, bias plots confirmed this observation of wider negative bias for Friedewald estimation in these moderately hypertriglyceridaemic subjects. CONCLUSION: For most routine laboratories the options immediately available for assessment of lipid levels are the Friedewald equation or the direct measurement. The Friedewald equation and the direct assay method for LDL cholesterol are about equally good for assessment of the LDL status in patients with chronic renal disease and plasma TG <4.0 mmol/l. Where there are restraints on laboratory budgets, it would appear appropriate that the more expensive direct assay method be restricted to cases in whom plasma TG >4.0 mmol/l or to patients who, for whatever reason, are unable to produce fasting samples.

Adolescent↗

PubMed1997

The prevalence of insulin resistance and other cardiovascular disease risk factors in healthy elderly southwestern Nigerians.

We assessed the prevalence of coronary heart disease (CHD) risk factors including insulin resistance in 500 (205 males, 295 females) healthy elderly (age > 55 years) indigenous, low socioeconomic group Yorubas residents in either an urban slum (n = 240) or a rural town (n = 260) in southwestern Nigeria. Anthropometric indices, blood pressure and fasting plasma levels of glucose, lipids, insulin and insulin resistance were measured. The results indicated that: (i) gross obesity (4.4%), diabetes (1.6%), hyperlipidaemia (0.2%) and cigarette smoking (4.8%) were relatively uncommon in the population, although the prevalence of hypertension (30%) was higher than previously reported from this population; (ii). the subjects had a relatively high prevalence of multiple CHD risk factors (about 20% had > 4 risk factors), an observation considered paradoxical in view of the reportedly low CHD prevalence in this population; (iii) these CHD risk factors (increased body mass and blood pressure (BP), hyperinsulinaemia and insulin resistance) were more prevalent in the women and in urban residents; (iv) hyperinsulinaemia (20%) and insulin resistance (35%) were common in the population, and were associated, on regression analyses, to such other CHD risk factors as BP and body mass, particularly in women, suggesting, as in Caucasians, that insulin resistance could be an important index of CHD risk; and (v) the excess of multiple CHD risk factors in the women, is due at least in part, to their increased tendency to obesity (8%) and reduced physical activity (83%). This study concludes that: (i) despite the high prevalence of multiple risk factors in this population, CHD prevalence is low, indicating the supremacy of such major risk factors as diabetes and hyperlipidaemia (relatively uncommon here) in the development of CHD; and (ii) potentially the greatest CHD risk is in the elderly women especially if relatively overweight, physically inactive and resident in an urban centre. While further confirmatory studies are necessary in younger subjects and across societal socioeconomic strata, our results nonetheless suggest that attempts to maintain the CHD prevalence at low levels in this population should include efforts directed at reducing excess body weight particularly in women, and advice on maintenance of a traditional diet to keep lipid levels and diabetes prevalence low.

Age Distribution↗

PubMed1997

Lipoprotein(a), tissue plasminogen activator and plasminogen activator inhibitor 1 levels in hyperlipidaemic patients in Kuwait.

Plasma levels of lipoprotein(a) [Lp(a)], tissue plasminogen activator (tPA) and plasminogen activator inhibitor type 1 (PAI-1) were assessed in addition to anthropometry and levels of glucose, total cholesterol, triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and apo A1 and B in 73 patients (36 men and 37 women) with primary hyperlipidaemia (group NDHL) in Kuwait. Lp(a) levels (212 mg L-1, 8-600 mg L-1, median and range) were similar to those obtained in a matched group of 32 non-insulin-dependent diabetes mellitus (NIDDM) patients with hyperlipidaemia (218 mg L-1, 50-610 mg L-1) and slightly higher, although not significantly so (P = 0.06), than levels seen in 68 healthy normolipidaemic control subjects (182 mg L-1, 70-488 mg L-1). tPA levels (8.4 ng mL-1, 3.8-18.4 ng mL-1, median and range) in group NDHL were lower than in the diabetic group (11.4 ng mL-1, 5.2-14.2 ng mL-1) but higher than in the healthy control subjects (7.4 ng mL-1, 2.8-12.6 ng mL-1). PAI-1 levels in group NDHL (40.4 ng mL-1, 8.6-55 ng mL-1, median and range) were higher than in the control subjects (32.5 ng mL-1, 14.6-46.4 ng mL-1) but lower than in diabetic patients (43.8 ng mL-1, 15.6-55 ng mL-1). Hyperlipidaemia phenotype (hypercholesterolaemia or hypertriglyceridaemia) did not influence tPA and PAI-1 levels, but Lp(a) levels were significantly lower with hypertriglyceridaemia. Gender, cigarette smoking and racial origin (Kuwaitis, other Arabs or South Asians) did not affect Lp(a), tPA and PAI-1 levels, but tPA levels were higher in postmenopausal subjects. Low-density lipoprotein (LDL) levels (whether in total cholesterol or as apo B) correlated significantly (P < 0.05) with Lp(a) levels. tPA levels were correlated with age and the plasma levels of glucose and uric acid (P < 0.05); this correlation with glucose may explain the high levels associated with diabetes, whereas the age association might account not only for the differences observed between group NDHL and the younger control group but also for the higher levels in the postmenopausal women. PAI-1 levels correlated with tPA and triglyceride (TG) levels in the groups of subjects (normo- and hyperlipidaemic). In the normolipidaemic control group, the significant associations of tPA and PAI-1 were with body mass, expressed as the body mass index or the waist-hip ratio. These results suggest that different factors influence the plasma levels of the prothrombotic factors Lp(a), tPA and PAI-1 in healthy control subjects and in patients with hyperlipidaemia. In the latter, hyperlipidaemia phenotype, age, glycaemic status and uric acid levels are important determinants of the levels of these prothrombotic variables, whereas in the healthy, young control population, body mass was the single important association with tPA and PAI-1.

Adolescent↗

PubMed1996

Are body mass or insulin resistance independently associated with cardiovascular risk factors in non-diabetic elderly Nigerians?

The aim was to establish whether risk factors for cardiovascular disease (CVD) are positively and independently associated with fasting insulin and/or body mass and waist-hip ratio in healthy elderly Nigerian subjects. Fasting plasma glucose, insulin, total cholesterol, triglycerides, blood pressure, and basal insulin resistance (HOMA method) were measured in 500 healthy elderly (> or = 55 years) Nigerian volunteers (295 men, 205 women). Associations between blood pressure, triglycerides or cholesterol and fasting insulin, HOMA, body mass index (BMI) or waist-hip ratio were examined using linear regression. Age was controlled for in all analyses. In men, diastolic and systolic blood pressure were strongly associated with BMI, while there was no evidence of an independent relationship with fasting insulin or HOMA. Triglycerides were strongly associated with waist-hip ratio, with a weaker independent association with HOMA but not fasting insulin; fasting insulin and HOMA showed strong independent associations with total cholesterol. In women diastolic and systolic blood pressure were also strongly associated with BMI, but there was an independent relationship with fasting insulin for diastolic blood pressure and a less significant (p = 0.057) one for systolic blood pressure. Triglycerides were significantly associated with BMI but none of the other variables; there were no significant associations with cholesterol. There was no evidence of interaction between fasting insulin or HOMA and BMI or waist-hip ratio. The results suggest the hypotheses that in this population BMI or waist-hip ratio are stronger determinants of blood pressure and triglyceride levels than fasting insulin or HOMA, and that where insulin does play a role its effects are separate and additive.

Age Factors↗

PubMed1996

Urinary iodine excretion in mothers and their breast-fed children in relation to other childhood nutritional parameters.

OBJECTIVE: There is currently no coordinated policy on the epidemiology and control of iodine deficiency disorders (IDD) in many parts of Africa even where these disorders are endemic. Assessment of the urinary iodine excretion is believed to give the best index of the prevalence of IDD in the community. This study aimed to establish whether: (i) the breast-fed child of an iodine replete mother was protected from IDD and, (ii) infants at risk of IDD and in need of immediate iodine supplementation could easily be identified through simple screening methods. DESIGN: Randomized, cross-sectional study. SETTING: A tertiary care infant welfare clinic in Ibadan, South-western Nigeria, a geographical area recognised to be outside Nigeria's endemic goitre belt (goitre prevalence < 5.0%). SUBJECTS: 68 healthy mother-child pairs. The children were all aged 9-18 months and breast-fed almost exclusively. INTERVENTIONS: Nil. METHODS: The relationships of anthropometric, iodine status (casual urinary iodine (I) and iodine/creatinine ratio (I/Cr)) and nutritional indices (weights, haematocrits) of the mothers with those of their breast-fed children were assessed, as well as how these parameters differed between the children classified on the basis of their mid-upper arm circumference, MUAC, as: (A) borderline malnourished, MUAC < 13.5 cm and, (B) well nourished, MUAC > 13.5 cm. RESULTS: The maternal values for I and I/Cr were significantly (p < 0.001) greater than those of their breast-fed infants, although the respective mother-child pair values correlated positively (I, r 0.47; I/Cr, 0.21; both p < 0.05). There was thus a gradient in iodine status between the mother and her breast-fed infant that is unfavourable to the growing child; the latter may thus require iodine supplementation in spite of the fact that the mother is iodine replete. Among the children, those considered well nourished (Group B) had similar iodine status parameters as those considered poorly nourished (Group A) suggesting that malnutrition alone should not be the determinant of the prioritization (or otherwise) of iodine supplementation in a population with coexistent iodine deficiency and malnutrition. Mean values for (I) in all the children (9.9 micrograms/dl) fell in the iodine deficiency range ( < 10 micrograms/dL), although all the mothers were iodine replete (mean urinary (I) 14.5 micrograms/dL), despite the fact that all resided in a non iodine deficient area. CONCLUSION: The study suggests that: (i) the breast-fed child of an iodine replete mother resident in a non-iodine deficient area may be iodine deficient and in need of iodine supplementation; (ii) malnutrition, as defined by the simple community screening method of measuring the MUAC, will not accurately identify those infants in immediate need of iodine supplementation. These observations have important implications for planning IDD control programmes in Africa.

Adult↗

PubMed1996

Clinical experience with adolescent diabetes in a Nigerian teaching hospital.

Diabetes mellitus presenting in adolescents age 10 to 20 years accounts for less than 5% of all diabetes in tropical African countries. Consequently, inadequate attention is paid to the medical and psychosocial problems attendant on adolescent diabetes in those countries. This article highlights our clinical experience in the management of 30 adolescent diabetic subjects who presented consecutively in the diabetic clinic of a major Nigerian teaching hospital. In these patients, adolescent diabetes appeared heterogeneous, comprising classical insulin-dependent diabetes mellitus (IDDM) in approximately 80%; the remaining fraction (20%) was contributed variably by malnutrition-related diabetes (MRDM) and an "atypical" form of IDDM. The most common medical complications were recurrent hypoglycemia, ketoacidosis, and infections. About 80% of the patients were poor, and up to two thirds had to withdraw from school or trade because of recurrent illness. One third of the girls had a history of unwanted pregnancies. Almost all (93%) had a history of general rebelliousness and clinic truancy. Therefore, the high prevalence of acute metabolic decompensation may be related to the increased frequency of psychosocial problems, especially poverty, in these patients. It is suggested that agencies in tropical Africa increase welfare facilities for adolescent chronic disease, and also establish and encourage clinics dedicated to adolescent diabetes care.

Adolescent↗