CST3 and Alzheimer disease: The AD‐HFpEF cohort had worse renal function than the S‐HFpEF group (serum creatinine 1.6 mg/dL versus 1.2 mg/dL, P<0.001; cystatin C 1.7 mg/L versus 1.4 mg/L, P<0.001; eGFR40 40.0 mL/min per 1.73 m2 versus 53.5 mL/min per 1.73 m2, P<0.001) and higher levels of NT‐pro BNP (3146 pg/mL versus 648.1 pg/mL, P<0.001).