Abstract 106: The Association Between Overnight Rostral Fluid Shift and Sleep Disordered Breathing in Patients With Treatment Resistant Hypertension

Background: Sleep disordered breathing (SDB) is an important modifiable risk factor of treatment resistant hypertension (TRH). Overnight rostral fluid shift from lower extremities is associated with the severity of SDB in patients prone to fluid accumulation (e.g. TRH, heart failure, and end-stage renal disease). However, the association between overnight rostral fluid shift and SDB in Japanese patients with TRH remains unclear. Methods: All patients with TRH underwent polysomnography. Neck circumference (NC) and leg fluid volume (LFV) were measured by tape measure and bioelectrical impedance just before sleep and after waking up. Correlation between apnea-hypopnea index (AHI), overnight change of LFV (ΔLFV), and overnight change of NC (ΔNC) were assessed by regression analysis. Results: Total 11 patients were examined (7 men [63%], Age: 62.6±13.4 years, body mass index: 28.1±4.2 kg/m 2 ). Mean AHI, ΔLFV, and ΔNC were 30.5±24.1/h. -267.5±156.1 ml, and 0.4±0.5 cm, respectively. ΔLFV correlated significantly with ΔNC (r=-0.63; P=0.04). Besides, both ΔLFV and ΔNC were significantly associated AHI respectively (ΔLFV, r=-0.92; P<0.01, ΔNC, r=0.67; P=0.02). In the stepwise regression analysis including estimated glomerular filtration rate, B-type natriuretic peptide along with ΔNC and ΔLFV, onlyΔLFV was the significant independent correlate with AHI, Conclusion: In Japanese patients with TRH, overnight rostral fluid shift contributes to the worsening of SDB, in association with the increase in NC.