The Correlation between the Serum Level of Adropin and Blood Pressure: A Case-Control Study

Background: Hypertension is considered a fundamental health issue globally, and adropin is a vascular endothelial protection factor. The increasing prevalence of Hypertension (HTN); i.e., 20 - 50%, among adult populations in developed countries is one of the most common causes of Cardiovascular Diseases (CVDs). HTN is also the major modifiable risk factor for stroke (both ischemic and hemorrhagic). Adropin has the potential to protect the endothelium by increasing the expression of Nitric Oxide (NO) synthesis in the endothelium. Nonetheless, few studies have been conducted on the role of adropin in regulating blood pressure.

Objectives: The present study aimed to assess the adropin level and its relationship with blood pressure.

Methods: The present observational, case-control study was conducted on 40 hypertensive and 40 non-hypertensive patients. The patients’ data such as gender, age, years passed since HTN diagnosis, and blood pressure were recorded by the researcher. Then, adropin was measured by the Enzyme-Linked Immunosorbent Assay (ELISA) technique. After all, the significance of the relationship between the variables was statistically analyzed.

Results: The mean level of adropin was 5.44 ± 1.31 pg/mL in the study population. This measure was 4.91 pg/mL in the case group and 5.98 pg/mL in the control group, and the difference was statistically significant (P < 0.01). The results of ANCOVA showed that mean level of adropin was 1.19 units (24.5%) lower in the case group than in the control group after adjusting for age. The results also revealed a significant difference in the mean adropin level of the hypertensive patients based on the years passed since diagnosis (P < 0.01). Moreover, a negative correlation was observed between the adropin level and systolic blood pressure (rs = -0.273, n = 80, P = 0.014) and diastolic blood pressure (rs = -0.273, n = 80, P = 0.008). However, no significant correlation was found between age and adropin level (rs = -0.173, n = 80, P = 0.124).

Conclusions: Hypertensive patients had lower adropin levels in comparison to non-hypertensive ones. In addition, increase in the number of years passed since diagnosis was associated with decreased adropin levels.