Association of Metabolic Markers of Insulin Resistance with Blood Pressure in Prehypertensive Adults in Makurdi, Nigeria

Background of Study: Previous studies observed insulin resistance in the hypertensive population. However, evidence-based studies of insulin resistance in prehypertension are scant.

Aim: Our study aimed at determining the presence of insulin resistance and its correlation with blood pressure in prehypertensive adults.

Materials and Methods: This was a case-control study involving randomly selected 70 healthy adults in Makurdi, Nigeria. Anthropometric parameters and metabolic markers of insulin resistance (fasting plasma glucose (FPG), homeostasis model assessment of insulin resistance [HOMA-IR], fasting serum insulin [FSI], triglycerides [TGs], triglyceride/high density lipoprotein cholesterol [HDL-C] ratio [TG/HDL-C]) in apparently healthy adults were measured. The metabolic markers of IR in 35 prehypertensives were compared with anthropometrically matched 35 normotensive controls using the student’s t-test. Associations of blood pressure (systolic-SBP and diastolic-DBP) with metabolic markers of insulin resistance in prehypertensives and normotensives were determined using Pearson correlation analysis.

Results: A significantly elevated (P<0.05) SBP, DBP, FSI, and HOMA-IR was observed in prehypertensives compared to matched normotensive controls. A significant positive correlation (P<0.01) was observed between SBP and insulin (r=0.762), HOMA-IR (r=0.756), TGs (r=0.586), TG/HDL-C (r=0.499); DBP and insulin (r=0.659), HOMA-IR (r=0.634), TGs (r=0.469), TG/HDL-C (r=0.469) in prehypertensives. In normotensives, a significant positive correlation (P<0.05) was observed between DBP and TGs (r=0.371), TG/HDL-C (r=0.376); age (r=0.372), BMI (r=0.523), WC (r=0.338).

Conclusion: Our study shows that insulin resistance is associated with elevated blood pressure and could mediate the progression of normotension through prehypertension to hypertension.