Association between C reactive protein and microvascular and macrovascular dysfunction in sub-Saharan Africans with and without diabetes: the RODAM study

Abstract

Introduction: Although inflammation assessed by elevated C reactive protein (CRP) concentration is known to be associated with risk of cardiovascular disease, its association with microvascular and macrovascular dysfunction in diabetes and non-diabetes remains unclear. We examined the association between CRP and diabetes and associated microvascular and macrovascular dysfunction in sub-Saharan Africans with and without diabetes.

Research design and methods: Cross-sectional analyses of baseline data from the multicenter RODAM study (Research on Obesity and Diabetes among African Migrants) including 5248 Ghanaians (583 with diabetes, 4665 without diabetes) aged 25-70 years were done. Logistic regression analyses were used to examine the associations between CRP Z-scores and diabetes and microvascular (nephropathy) and macrovascular (peripheral artery disease (PAD)) dysfunction, with adjustments for age, sex, site of residence, smoking, body mass index, systolic blood pressure, and low-density lipoprotein cholesterol.

Results: In the fully adjusted models, higher CRP concentration was significantly associated with diabetes (adjusted OR 1.13; 95% CI 1.05 to 1.21, p=0.002). In participants with diabetes, higher CRP concentration was associated with PAD (1.19; 1.03 to 1.41, p=0.046) but not nephropathy (1.13; 0.97 to 1.31, p=0.120). Among participants without diabetes, higher CRP concentration was associated with higher odds of PAD (1.10; 1.01 to 1.21, p=0.029) and nephropathy (1.12; 1.04 to 1.22, p=0.004).

Conclusions: In this study, higher CRP concentration was associated with higher odds of diabetes in sub-Saharan Africans. Also, higher CRP concentration was associated with higher odds of nephropathy and PAD in non-diabetes and higher odds of PAD in diabetes. CRP may be an important marker for assessment of risk of diabetes and risk for PAD and nephropathy in sub-Saharan Africans with and without diabetes.

Keywords: C-reactive protein; adult diabetes; inflammation; microvascular and macrovascular complications.

Figure 1

Flow chart of study design and inclusion in analyses. CRP, C reactive protein.

Figure 2

OR of diabetes per SD increase in the CRP concentration. Model 1 was unadjusted; model 2 adjusted for age and sex; model 3 adjusted additionally for site of residence, smoking, BMI, systolic blood pressure, and LDL-cholesterol. SD of mean CRP=8.20 mg/L for the whole group (n=5248); SD of mean CRP=2.07 mg/L for the subgroup of participants with CRP concentrations ≤10 mg/L (n=4962). BMI, body mass index; CRP, C reactive protein; LDL, low-density lipoprotein.