Abstract P045: Association of Renal Function and Blood Pressure Reactivity to the Cold Pressor Test: the GenSalt Study

Abstract

Exaggerated blood pressure (BP) reactivity to the cold pressor test (CPT) has been associated with increased risk of hypertension and cardiovascular disease. We examined the association between estimated glomerular filtration rate (eGFR) and BP reactivity to the CPT among the participants of the Genetic Epidemiology Network of Salt Sensitivity (GenSalt) study. We conducted the CPT among 1,961 GenSalt participants from north rural China. The average age of the participants (SD) was 39.9 (10.2) years, and 52.8% of the participants were male. BP was measured using a standard mercury sphygmomanometer prior to and at 0, 1, 2, and 4 minutes after the participants immersed their right hand in ice water for 1 minute. The maximum responses (SD) were 13.9 (10.2) and 7.8 (6.2) mm Hg for systolic and diastolic BP, respectively. Serum creatinine was measured and used to calculate eGFR using the Modification of Diet in Renal Disease (MDRD) formula. The average eGFR (SD) was 87.7 (25.8)ml/min per 1.73m 2 . After adjusting for multiple covariates, including age, sex, body mass index, baseline BP, education, cigarette smoking, alcohol drinking, and physical activity, eGFR was significantly associated with maximum systolic BP response to the CPT (P < 0.0001). A standard deviation decrease in eGFR was associated with a 1.2 mm Hg higher maximum systolic BP response to the CPT. In addition, we observed that the effect of eGFR on BP response to the CPT increased with age ( P for interaction < 0.0001). For example, a standard deviation decrease in eGFR was associated with a 0.6, 1.1, and 2.5 mm Hg greater maximum systolic BP response to the CPT for age groups < 35, 35-44, and ≥ 45 years, respectively. In conclusion, this large study suggests a relationship between decreased renal function and greater cardiovascular reactivity to stress. Further investigation is warranted to identify factors that mediate this relationship and potential adverse clinical consequences of cardiovascular hyperreactivity in subjects with reduced renal function.