[Homocysteinemia]

Elevated homocysteine and differential risks of the renal function decline in hypertensive patients

IMPORTANCE

In several studies, homocysteine (hcy) is a documented risk for predicting renal function decline. The differential effects between various levels of hcy have yet to be quantified.

METHODS

In this retrospective cohort study, data was obtained from patients admitted to our hospital from Jan. 2015 to Apr. 2019. Hyperhomocysteinemia is defined as serum hcy concentration >15 μmol/L. Study population eligible subjects included those who had a diagnostic hypertension. The endpoint event was defined as a fall in eGFR between the follow-up and baseline. Logistic regression models were used to examine the related ratio risk results. Cox models were performed to explore the effect of study groups on survival. The significant level was set at a P value of <0.05.

RESULTS

A total of 7,240 patients presented over 3,564 person-years and were retrospectively enrolled in this study. Overall, 1,145 patients had a hypertension grade 1 [15.8%], 2,455 hypertension grade 2 [33.9%], and 3,640 hypertension grade 3 [50.27%]. Among patients who developed hyperhomocysteinemia (3,604 patients), their renal function had a higher long-term rate of decline (P= .005, hazard ratio (HR) = 1.097, 95% confidence interval (CI) [1.028, 1.171]), compared to patients who didn't developed hyperhomocysteinemia (3,636 patients). After adjusting for covariables, patients' (hcy > 15 μmol/L group) eGFR decreasing had a more hazard ratio (P = .002, aHR= 1.112; 95%CI [1.039, 1.190]). Compared with the serum hcy ≤ 10 μmol/L patients, their renal function decline ratio was higher in the 10 μmol/L < hcy ≤ 15 μmol/L group (P = .008, HR= 1.195, 95% CI [1.048,1.364]), 15 μmol/L < hcy ≤ 20 μmol/L group (P = .000, HR= 1.400, 95%CI [1.227,1.597]), and hcy > 20 μmol/L group (P = .000, HR = 1.475, 95%CI [1.305,1.667]).

CONCLUSION

Elevated hcy concentration increases the risk of renal function decline in hypertensive patients. Hcy concentration might also be considered as an important factor in risk stratification of the renal function for hypertensive patients.