In Nigeria, reports on the prevalence of modifiable cardiovascular disease (CVD) risk factors are scarce. In addition, socio-economic status (SES), an important component of the socioeconomic gradient in CVD and its risk factors has not been clearly elucidated. This study sought to assess the prevalence of CVD risk factors and how the difference in prevalence and accessibility to CVD risk screening across income levels and educational backgrounds contributes to disease diagnosis in rural and urban Nigerian adults. A cross sectional study was carried out on a sociocultural ethnic group of persons living in rural and urban settings. All participants were aged ≥ 18 years. The WHO STEPS questionnaire was used to document the demographics, history of previous medical check-up or screening, anthropometric and biochemical measurements of the participants. Average income level and educational status were indicators used to assess the impact of SES. Multivariate analyses were performed to assess any difference between the geographical locations and SES indicators, and prevalence of CVD risk factors and access to CVD risk screening. The 422 participants (149 males and 273 females) had mean age (± standard deviation) of 38.3 ± 20.5 and 42.9 ± 20.7 years, respectively. Only total cholesterol (p = 0.001), triglyceride (p = 0.005), high density lipoprotein cholesterol (HDL) (p < 0.0001), body mass index (BMI) (p = 0.03) and average income rate (p = 0.01) showed significant difference between gender groups. Overall prevalence of prediabetes (4.9%), diabetes (5.4%), hypertension (35.7%), low HDL (17.8%), hypertriglyceridemia (23.2%), hypercholesterolemia (38.1%) and central obesity of 52.2% was recorded. Except between total cholesterol (p = 0.042) and HDL (p = 0.017), other CVD risk factors did not show a statistical significance across income levels. Participants with ‘university and postgraduate education’ had higher access to blood pressure and blood glucose screening compared to other educational groups; and this showed a statistical significance. This study has shown that a significant number of modifiable CVD risk factors exist in the rural and urban migrants of an adult Nigerian population. While income level did not affect the CVD risk factor prevalence, it did affect accessibility to CVD risk screening. There is a need for access to diagnosis of modifiable risk factors at all levels of society.

Diabetes mellitus is a chronic disease in its own right and is also regarded as a cardiovascular risk factor as well as a cardiovascular disease, due to its ability to progress to a stage of cardiovascular co-morbidity. The pathophysiology of cardiovascular complications in diabetes is reported to involve hyperglycaemia-induced oxidative stress. The erythrocyte has an array of endogenous antioxidants involved in quenching oxidant production and the exponential chain reactions in diabetes. When the erythrocyte is oxidatively stressed, as demonstrated by depleted reduced glutathione and/or increased malondialdehyde in its cell membrane, the risk of diabetes progression and its cardiovascular sequelae, including atherosclerosis and coronary artery disease, is increased. Virtually all studies that determined erythrocyte malondialdehyde and glutathione in diabetes show consistently increased and reduced levels, respectively. Furthermore, cardiovascular complications of diabetes are reported to commence at the prediabetes stage. Current coronary artery disease screening programmes based on the presence of two or more risk factors are failing to identify those with increased risk of diabetes and cardiovascular complications, thereby limiting early interventions. Screening that includes erythrocyte oxidative stress determination may provide an additional marker for both preclinical and advanced disease. In this review, a concise description of the involvement of erythrocyte oxidative stress in diabetes mellitus and its cardiovascular sequelae is presented. Antioxidant action and interaction in the erythrocyte are also described, with emphasis on why current coronary artery disease screening markers cannot be regarded as erythrocyte oxidative stress markers.

The aim of the study was to ascertain whether there is variation in the fibrinolytic/coagulation component of diabetes associated with disease progression to macrovascular complications and whether D-dimer can discriminate such variation. A total of 343 participants were selected based on clinical status and divided into 7 groups: control, family history of diabetes, pre-diabetes with/without CVD, diabetes with/without CVD and CVD only. Plasma D-dimer was tested. Statistical analysis was performed on log normalised data by ANOVA, Fisher’s LSD post hoc test. After the initial analysis, data were classified and re-analysed by quartiles, interquartile range and 95^th percentile. An overall significant difference between groups (p<0.002) and a steady rise in D-dimer levels that became increasingly higher than control as the disease progressed from pre-diabetes to cardiovascular complications was observed. A statistically significant difference was observed between control versus diabetes (p<0.0005). Analysis of data by quartiles and percentiles gave qualitatively similar results, but a greater significant difference between control versus pre-diabetes at 3rd quartile and interquartile range (p<0.014). We report changes in D-dimer levels that may indicate diabetes disease progression to macrovascular complications. Using D-dimer in conjunction with other biomarkers to identify stages of disease progression, commencing from pre-diabetes and continuing to development of asymptomatic and clinical cardiovascular disease in diabetes mellitus, is worthy of consideration.

Hyperglycaemia-induced oxidative stress is implicated as a cause of increased whole blood viscosity (WBV), which is a clinically modifiable risk factor for cardiovascular disease (CVD). However, whether or not there is variation in WBV at different stages of diabetes mellitus (DM) has yet to be confirmed. The sensitivity of underlying oxidative stress has also yet to be investigated. A total of 154 participants representing different stages of DM pathogenesis were selected for the study. Healthy control, prediabetes, DM and DM+CVD groups were compared for variation in WBV levels. The prevalence of oxidative stress, indicated by abnormal levels of erythrocyte glutathione, malondialdehyde and methaemoglobin, associated with high WBV was evaluated. The results showed a statistically significant difference in WBV between groups (P<0.03). The level of viscosity was significantly lower in the control group relative to the prediabetes group (P<0.01) and DM+CVD group (P<0.04). There was no statistically significant difference between the DM+CVD and prediabetes groups. Greater than 76% prevalence of oxidative stress was shown to be associated with high WBV, reaching 95% prevalence in prediabetes. The study showed that WBV varies between individuals with different stages of diabetic macrovascular pathogenesis, including prediabetes. Redefining the criteria for use of WBV on the basis of sensitivity to underlying oxidative stress, rather than specificity to a disease condition, means that this easily performed test is an option to consider in an all-inclusive laboratory approach to early intervention against future diabetic macrovascular complications. This is particularly important for individuals with subclinical hyperglycaemia.