Serum reference intervals of micronutrients, vitamins, and interleukins among healthy adults in South-Western Nigeria.

Objectives: Clinical decision making depends mostly on appropriate application of numerical pathology reports from laboratory results, interpreted by comparison with reference intervals. We determined serum reference intervals of micronutrients, vitamins, and detectable interleukins among healthy adults in South-Western Nigeria. Design and methods: This prospective study used a priori selection approach in blood-donors. They were screened for conditions that could elicit cytokine production.Serum micronutrients were assayed using Atomic Absorption Spectrophotometry; interleukins and vitamins by high Performance Liquid Chromatography. The reference intervals (RIs) were estimated at 2.5th percentile and 97.5th percentile. Results: One hundred and eighteen (118) apparently healthy subjects, aged 18-56 years; 113 (95.8%) being 18-44years, and 5 (4.2%): 45-56 years; mostly males, 13 (11.02%) females, all Africans of Yoruba ethnicity.Estimated reference limits were: Zinc: 9.49-20.54 µmol/L, Selenium: 0.50-1.11 µmol/L, Copper: 13.86-27.97 µmol/L, Iron: 14.19-32.07 µmol/L, Manganese: 6.24-16.37 nmol/L; Magnesium: 0.78-1.62 mmol/L.Vitamins: A-1.08-2.39 µmol/L; D: 59.89-164.42 µmol/L; E: 7.13-19.45 µmol/L; K: 0.16-0.42 nmol/L; B1: 74.09-201.56 nmol/L; B6: 0.12-0.29 nmol/L; B12: 155.55-407.96 pmol/L; C: 47.74-112.99 µmol/L.Detected interleukins (IL-1 to IL-18): IL-1: 0.58-1.24 ng/L, IL-2: 0.09-0.18 ng/L, IL-3: 0.39-0.89 ng/L, IL-4: 0.27-0.58 ng/L, ….to IL-18: 0.74-1.56 ng/L. Conclusions: The RI derived from this study for serum micronutrient, vitamin and interleukin concentrations are the first published for our population. They are in general agreement with those published from other geographical climes but there are differences at the lower and upper limits of the RI. The study reinforces the importance of deriving RI for the population that a clinical laboratory will serve.

Serum Levels of Micronutrients, Magnesium, and Markers of Immunity (CD4+ ) in Antiretroviral-naïve HIV-infected Individuals: Relationships and Predictors.

BACKGROUND: HIV/AIDS may lead to micronutrient deficiencies and low CD4+ count. OBJECTIVES: We assessed the correlation of CD4+ count in antiretroviral-naïve patients with the serum levels of micronutrients as measures of the relationship between immunity and nutrition/malnutrition. METHODS: A case-control study of ninety consecutive newly diagnosed HIV/AIDS patients and ninety blood donors. Blood collected from controls and patients before HAART treatment were assayed for serum zinc, selenium, copper, manganese, and magnesium. RESULTS: The participants had non-significantly lower zinc (14.25±2.93µmol/l versus 14.58±3.69µmol/l, p=0.493), significantly lower selenium (0.38±0.08µmol/l versus 0.78±0.22µmol/l, p<0.001), manganese (7.06±0.87µmol/l versus 11.23±3.27µmol/l, p<0.001), and magnesium (1.02±0.21mmol/l versus 1.21±0.28mmol/l, p<0.001) when compared with the controls. The mean copper level was similar in both groups (18.88±3.1µmol/l and 18.82±5.12µmol/l, p=0.921). There was no correlation between the micronutrients and CD4+ count; however, there were strong positive correlations between the levels of zinc and copper, selenium, magnesium; copper and magnesium (p<0.001 respectively). Multivariate regression showed that all micronutrients were independent predictors of one another (p<0.001). CONCLUSION: HIV/AIDS results in serum micronutrient depletion with strong positive correlations between their levels; all micronutrients were independent predictors of one another. This significant positive relationships between the micronutrients, and magnesium; and all other micronutrients being independent predictors of each other signifies a synergistic or supportive relationship between micronutrient deficiencies and HIV/AIDS disease morbidity and progression. Serum micronutrients may not be qualified as direct markers or surrogates for CD4+ count in antiretroviral-naïve HIV-infected patients.

Risk Factor Characterization of Ischemic Stroke Subtypes Among West Africans.

BACKGROUND AND PURPOSE: To identify the qualitative and quantitative contributions of conventional risk factors for occurrence of ischemic stroke and its key pathophysiologic subtypes among West Africans. METHODS: The SIREN (Stroke Investigative Research and Educational Network) is a multicenter, case-control study involving 15 sites in Ghana and Nigeria. Cases include adults aged ≥18 years with ischemic stroke who were etiologically subtyped using the A-S-C-O-D classification into atherosclerosis, small-vessel occlusion, cardiac pathology, other causes, and dissection. Controls were age- and gender-matched stroke-free adults. Detailed evaluations for vascular, lifestyle, and psychosocial factors were performed. We used conditional logistic regression to estimate adjusted odds ratios with 95% CI. RESULTS: There were 2431 ischemic stroke case and stroke-free control pairs with respective mean ages of 62.2±14.0 versus 60.9±13.7 years. There were 1024 (42.1%) small vessel occlusions, 427 (17.6%) large-artery atherosclerosis, 258 (10.6%) cardio-embolic, 3 (0.1%) carotid dissections, and 719 (29.6%) undetermined/other causes. The adjusted odds ratio (95% CI) for the 8 dominant risk factors for ischemic stroke were hypertension, 10.34 (6.91-15.45); dyslipidemia, 5.16 (3.78-7.03); diabetes, 3.44 (2.60-4.56); low green vegetable consumption, 1.89 (1.45-2.46); red meat consumption, 1.89 (1.45-2.46); cardiac disease, 1.88 (1.22-2.90); monthly income $100 or more, 1.72 (1.24-2.39); and psychosocial stress, 1.62 (1.18-2.21). Hypertension, dyslipidemia, diabetes were confluent factors shared by small-vessel, large-vessel and cardio-embolic subtypes. Stroke cases and stroke-free controls had a mean of 5.3±1.5 versus 3.2±1.0 adverse cardio-metabolic risk factors respectively (P<0.0001). CONCLUSIONS: Traditional vascular risk factors demonstrate important differential effect sizes with pathophysiologic, clinical and preventative implications on the occurrence of ischemic stroke among indigenous West Africans.

Unraveling the risk factors for spontaneous intracerebral hemorrhage among West Africans.

OBJECTIVE: To characterize risk factors for spontaneous intracerebral hemorrhage (sICH) occurrence and severity among West Africans. METHODS: The Stroke Investigative Research and Educational Network (SIREN) study is a multicenter case-control study involving 15 sites in Ghana and Nigeria. Patients were adults ≥18 years old with CT-confirmed sICH with age-, sex-, and ethnicity-matched stroke-free community controls. Standard instruments were used to assess vascular, lifestyle, and psychosocial factors. Factors associated with sICH and its severity were assessed using conditional logistic regression to estimate odds ratios (ORs) and population-attributable risks (PARs) with 95% confidence intervals (CIs) for factors. RESULTS: Of 2,944 adjudicated stroke cases, 854 were intracerebral hemorrhage (ICH). Mean age of patients with ICH was 54.7 ± 13.9 years, with a male preponderance (63.1%), and 77.3% were nonlobar. Etiologic subtypes of sICH included hypertension (80.9%), structural vascular anomalies (4.0%), cerebral amyloid angiopathy (0.7%), systemic illnesses (0.5%), medication-related (0.4%), and undetermined (13.7%). Eight factors independently associated with sICH occurrence by decreasing order of PAR with their adjusted OR (95% CI) were hypertension, 66.63 (20.78-213.72); dyslipidemia, 2.95 (1.84-4.74); meat consumption, 1.55 (1.01-2.38); family history of CVD, 2.22 (1.41-3.50); nonconsumption of green vegetables, 3.61 (2.07-6.31); diabetes mellitus, 2.11 (1.29-3.46); stress, 1.68 (1.03-2.77); and current tobacco use, 14.27 (2.09-97.47). Factors associated with severe sICH using an NIH Stroke Scale score >15 with adjusted OR (95% CI) were nonconsumption of leafy green vegetables, 2.03 (1.43-2.88); systolic blood pressure for each mm Hg rise, 1.01 (1.00-1.01); presence of midline shift, 1.54 (1.11-2.13); lobar ICH, 1.72 (1.16-2.55); and supratentorial bleeds, 2.17 (1.06-4.46). CONCLUSIONS: Population-level control of the dominant factors will substantially mitigate the burden of sICH in West Africa.

Free radical attack on membrane lipid and antioxidant vitamins in the course of pre-eclamptic pregnancy.

BACKGROUND: Despite the volume of knowledge and daily reports on pre-eclampsia, its pathogenesis is still yet to be ascertained. Oxidative stress (oxidant (free radical) in excess of antioxidant) injury is one of the recently suggested pathogenetic mechanisms. This study, however, was designed to determine second and third trimesters of plasma malondialdehyde (product of free radical attack on membrane lipid) and vitamins C and E in pre-eclamptic Nigerian women. SUBJECTS AND METHODS: A Total of 100 subjects, each for pre-eclamptic, apparently normal and non-pregnant women qualified for the study. Venous blood samples were taken in the second and third trimesters of pregnancy and at the point of contact for non-pregnant women. Variables were analyzed using SPSS version 16, taking level of significance to be 0.05. RESULTS: Plasma malondialdehyde in the third trimester of normal pregnancy (2.03±0.71µmol/l) was found to be significantly higher than the one in the second trimester (1.65±0.62µmol/l) (p<0.0001). For pre-eclamptic subjects, the malondialdehyde in the third trimester (3.13±0.61µmol/l) was also higher than the malondialdehyde in the second trimester (3.00±1.21µmol/l). The mean vitamin C values for subjects with normal pregnancy were similar in the second and third trimesters (38.25±19.66 vs. 38.66±19.40; p=0.882). For subjects with pre-eclampsia, the mean Vit C values were also similar in the 2(nd) and 3(rd) trimesters (35.05±18.37 vs. 37.20±24.44µmol/l; p=0.175). Mean vitamin E values in the second and third trimesters were also similar for subjects with normal pregnancy (28.62±13.85 vs. 28.50±13.35µmol/l; p=0.950). A similar finding was observed in pre-eclamptic subjects (25.09±12.79 vs. 28.00±14.83µmol/l; p=0.067). CONCLUSION: There was an increased product of membrane lipid attack (malondialdehyde) with no change in plasma levels of vitamins C and E as pregnancy advances into the third trimester of both normal and pre-eclamptic pregnancies. Antioxidant vitamins may not be useful in stopping the progression of free radical attack on membrane lipid to control pre-eclampsia.

Biochemical parameters of liver function in artisans occupationally exposed to "vat dyes".

BACKGROUND: Vat dyes are the class of dyes used in textile dyeing in Abeokuta, South Western Nigeria. While some dyes (including vat dyes intermediates) have been associated with adverse effects on manufacturer's health, there is paucity of data on effects of occupational exposure to vat dyes among end users, such as those involved in textile dyeing and finishing. AIMS AND OBJECTIVES: To investigate the possible effect of occupational exposure to vat dyes on the functions of the liver. MATERIALS AND METHODS: Using convenience sampling technique, a cohort of dye workers (n=117) with a minimum of one year and a maximum of 60 years duration of exposure (mean =17.03 ± 1.19 years) were recruited in this study. Sixty traders, matched for age and sex and who had no previous exposure to vat dyes were selected as controls. A structured questionnaire was used to obtain information on demographic, occupational and environmental characteristics of the subjects. Plasma activities of alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and plasma concentrations of total protein, albumin and total bilirubin were measured using standard spectrophotometric methods. STATISTICAL ANALYSES: SPSS version 11.0 was used for statistical analyses. Tests of significance were carried out using Student's t test, and correlation co-efficient. RESULTS AND CONCLUSION: The activity of ALP and the concentrations of total protein and albumin were significantly lower (P <0.05) in the exposed group. ALT and AST activities were significantly higher (P <0.05) in the exposed group. Occupational exposure to vat dyes may result in sub-clinical adverse effects on the liver, involving inhibition of its synthetic function.