The circadian blood pressure rhythm in non-diabetic hemodialysis patients

Area of Science:

• Nephrology
• Cardiology
• Chronobiology

Background:

• Circadian blood pressure variation is crucial for cardiovascular health.
• Chronic hemodialysis (HD) patients exhibit altered blood pressure (BP) patterns.
• Understanding diurnal BP variability in HD patients is essential for managing cardiovascular risk.

Purpose of the Study:

• To investigate circadian blood pressure variation in non-diabetic chronic hemodialysis patients.
• To identify factors influencing diurnal BP variability on both HD and non-HD days.
• To explore the relationship between BP patterns and clinical parameters like ultrafiltration, plasma renin activity, and dialysis dose.

Main Methods:

• Studied 49 non-diabetic chronic hemodialysis patients.
• Monitored daytime and nighttime BP on HD and non-HD days.
• Classified BP diurnal variability patterns: Dipper, non-dipper (ND), and inverted dipper (ID).
• Analyzed ultrafiltration rate, plasma renin activity difference (dRen), and dialysis dose (Kt/V).

Main Results:

• No significant difference in daytime/nighttime BP between HD and non-HD days, but nighttime/daytime BP ratio increased on non-HD days.
• Over 75% of patients were classified as ND or ID.
• Lower ultrafiltration rate in Dippers compared to ND and ID.
• Higher dRen in ID patients compared to D and ND.
• Kt/V correlated significantly with nighttime BP fall.
• Ultrafiltration, dRen, and Kt/V were independent factors for abnormal BP diurnal variability.

Conclusions:

• Decreased nocturnal BP fall in HD patients is associated with increased extracellular fluid, even without overt overhydration.
• Insufficient dialysis dose (low Kt/V) may contribute to abnormal BP diurnal variability.
• Elevated dRen in ID patients suggests potential occult cardiovascular damage or baroreflex dysfunction.