The association between vitamin D deficiency and risk of renal event: Results from the Korean cohort study for outcomes in patients with chronic kidney disease (KNOW-CKD)

Backgrounds

Some observational studies have suggested a possible association between vitamin D deficiency and CKD. However, in most studies, the causality between low levels of vitamin D and risk of renal events could not be explained. We investigated the relationship between vitamin D deficiency and risk of severe CKD stage and renal event in a large-scale prospective cohort study.

Methods

We used data from a prospective cohort of 2,144 patients with available information on serum 25-hydroxyvitamin D (25(OH)D) levels at baseline from KNOW-CKD, 2011-2015 were included. Vitamin D deficiency was defined as serum 25(OH)D levels < 15 ng/mL. We performed a cross-sectional analysis to elucidate the relationship between 25(OH)D and CKD stage using baseline CKD patient data. We further examined a cohort analysis to clarify the association between 25(OH)D and risk of renal event. Renal event was a composite of the first occurrence of a 50% decline in eGFR from the baseline value or the onset of CKD stage 5 (initiation of dialysis or kidney transplantation) across the follow-up period. We also investigated the associations of vitamin D deficiency with risk of renal event according to diabetes and overweight status.

Results

Vitamin D deficiency were significantly associated with an increased risk of severe CKD stage - 1.30-fold (95% CI: 1.10-1.69) for 25(OH)D. Deficiency of 25(OH)D with 1.64-fold (95% CI: 1.32-2.65) was related to renal event compared with the reference. Furthermore, vitamin D deficiency patients with presence of DM and overweight status also displayed higher risk than non-deficient patients for risk of renal event.

Conclusion

Vitamin D deficiency is associated with significantly increased risk of severe CKD stage and renal event.

Use of percutaneous transluminal renal angioplasty in atherosclerotic renal artery stenosis: a systematic review and meta-analysis

OBJECTIVE

For patients with atherosclerotic renal artery stenosis (ARAS), the role of percutaneous transluminal renal angioplasty (PTRA) remains inconclusive. This study aimed to comparatively evaluate the benefits of best medical therapy (BMT) plus PTRA and BMT alone in treating ARAS.

METHODS

We performed a systematic review and meta-analysis, and searched for all randomized, controlled trials that reported patients with ARAS. The effectiveness and safety in the BMT plus PTRA and BMT alone groups were estimated, taking into account hypertension, stroke, renal events, cardiac events, and mortality.

RESULTS

Nine randomized, controlled trials involving 2309 patients were included. In the BMT plus PTRA group, the incidence of refractory hypertension was significantly lower compared with that in the BMT alone group (odds ratio 0.09; 95% confidence interval 0.01, 0.70). However, there were no significant differences in the rates of stroke, renal events, cardiac events, cardiac mortality, and all-cause mortality between the two groups.

CONCLUSIONS

PTRA plus BMT improves blood pressure in patients with ARAS, but there is insufficient evidence for this therapy in improving stroke, renal events, cardiac events, and cardiac and all-cause mortality.

Effects of an Antihypertensive Combination in Japanese Hypertensive Outpatients Based on the Long-acting Calcium Channel Blocker Benidipine on Vascular and Renal Events: A Sub-analysis of the COPE Trial

BACKGROUND

In the trial known as COPE (Combination Therapy of Hypertension to Prevent Cardiovascular Events), three benidipine (a Calcium Channel Blocker; CCB) regimens were compared. Hypertensive Japanese outpatients aged 40-85 years (n=3,293) who did not achieve the target blood pressure of <140/90 mmHg with benidipine 4 mg/day were treated with the diuretic thiazide (n=1,094) or a β-blocker (n=1,089) or an additional Angiotensin Receptor Blocker (ARB; n=1,110). A significantly higher incidence of hard cardiovascular composite endpoints and of fatal or non-fatal strokes was observed in the benidipine-β-blocker group compared to the benidipine-thiazide group.

OBJECTIVE AND METHODS

We further evaluated the treatment effects of the three benidipine-based regimens on vascular and renal events in a sub-analysis of the COPE patients.

RESULTS

A total of 10 vascular events (0.8 per 1,000 person-years) including one aortic dissection (0.1 per 1,000 person-years) and nine cases of peripheral artery disease (0.8 per 1,000 person-years) were documented, as was a total of seven renal events (0.6 per 1,000 person-years). No significant differences in vascular and renal events were revealed among the three treatment groups: vascular events, p=0.92; renal events, p=0.16, log-rank test.

CONCLUSION

Blood pressure-lowering therapy with benidipine combined with an ARB, β-blocker, or thiazide was similarly effective in the prevention of vascular and renal events in hypertensive outpatients, although there are not enough events to compare the difference in the three treatment groups.