Search

Intradialytic hypotension (IDH) is a common complication of hemodialysis (HD) and is associated with a higher risk of cardiovascular (CV) events and mortality. CV events are more common on the days of HD, especially following the longer interdialytic interval. We investigated the risk of IDH according to day of HD in adults undergoing in-center, thrice-weekly HD in the Hemodialysis (HEMO) Study (N = 1,837 patients; n = 64,474 sessions), and the DaVita Clinical Research biorepository [BioReG]) (N = 952 patients; n = 61,197 sessions). Random effects logistic regression models assessed the risk of IDH (defined as nadir intra-HD systolic blood pressure [SBP]

Magnesium is involved in the regulation of blood pressure (BP). Abnormalities in serum magnesium are common in chronic kidney disease (CKD), yet its association with the development of hypertension and CKD progression in patients with CKD is unclear. We analyzed data from 3866 participants from the CRIC Study (Chronic Renal Insufficiency Cohort). Linear regression assessed the association of serum magnesium with baseline systolic BP (SBP) and diastolic BP (DBP). Logistic regression explored the association of serum magnesium with various definitions of hypertension. Cox proportional hazards models explored assessed the risk of incident hypertension and CKD progression. Mean serum magnesium was 2.0 mEq/L (±0.3 mEq/L). Higher magnesium was associated with lower SBP (−3.4 mm Hg [95% CI, −5.8 to −1.0 per 1 mEq/L]) and lower DBP (−2.9 mm Hg [95% CI, −4.3 to −1.5 per 1 mEq/L]). Higher magnesium was associated with a lower risk of American Heart Association–defined hypertension (SBP≥130 mm Hg or DBP≥80 mm Hg) at baseline (adjusted hazard ratio, 0.65 [95% CI, 0.49–0.86 per 1 mEq/L]), a lower risk of suboptimally controlled BP (SBP≥120 mm Hg or DBP≥80 mm Hg; adjusted odds ratio, 0.58 [95% CI, 0.43–0.78 per 1 mEq/L]). In time-to-event analyses, higher baseline serum magnesium was associated with a nominally lower risk of incident CRIC-defined hypertension (adjusted hazard ratio, 0.77 [95% CI, 0.46–1.31 per 1 mEq/L]). Higher magnesium was associated with a significantly lower risk of CKD progression (adjusted hazard ratio, 0.68 [95% CI, 0.54–0.86 per 1 mEq/L]). In patients with CKD, higher serum magnesium is associated with lower SBP and DBP, and with a lower risk of hypertension and CKD progression. In patients with CKD, whether magnesium supplementation could optimize BP control and prevent disease progression deserves further investigation.

Background and Aims Intradialytic hypotension (IDH) affects up to 50% of maintenance hemodialysis (HD) patients and is associated with a higher risk of cardiovascular (CV) events and mortality. CV events are more common on the days of dialysis and are most pronounced following the longer interdialytic interval. We wished to investigate if the rates of IDH differed according to dialysis day. Method We examined data from adult patients undergoing in-center thrice-weekly maintenance HD (N= 975 patients/n=59,004 sessions from a large dialysis organization [LDO] and N=1,838 patients/n=64,407 sessions from the Hemodialysis [HEMO] Study). We fit random effects logistic regression models to determine the association of day of HD (Mon/Tue [HD1]; Wed/Thu [HD2]; Fri/Sat [HD3]) with various definitions of IDH. Models were adjusted for age, sex, race, Kt/V, membrane flux, heart failure, peripheral vascular disease, diabetes, access type (catheter vs. fistula vs. graft), pre-dialysis blood urea nitrogen, ultrafiltration rate, pre-HD systolic blood pressure (SBP). IDH definitions included Nadir90 (nadir intra-HD SBP Results Mean age was 60 years, 44% were female and 38% were black in the LDO cohort, while mean age was 58 years, 56% were female and 63% were black in HEMO. Nadir90 occurred in 15% of LDO and 11% of HEMO sessions; Nadir90/100 occurred in 18% of LDO and 14% of HEMO sessions; Fall20 occurred in 76% of LDO and 68% of HEMO sessions; Fall30 occurred in 60% of LDO and 50% of HEMO sessions. Overall, a monotonic increase in the risk of IDH was observed for HD2 and HD3 compared with HD1 for all IDH definitions in both cohorts (see Table and Figure). Conclusion We observed a consistent monotonic increase in the risk of IDH for HD2 and HD3, compared with HD1 in two separate cohorts of maintenance HD patients. Potential explanations may relate to progressive reduction in post-HD weight during the dialytic week, or perhaps more aggressive ultrafiltration in advance of the longer interval. Further research to determine the underling mechanisms is necessary to guide practicing nephrologists when individualizing the HD prescription.