Association between nocturnal blood pressure dipping patterns and left atrial reservoir strain in untreated adults with office-defined grade 1 essential hypertension
Background Abnormal nocturnal blood pressure (BP) profiles may expose the left atrium to persistent hemodynamic load before overt remodeling occurs. This study evaluated the association between nocturnal systolic blood pressure (SBP) dipping patterns and left atrial reservoir strain (LARS) in untreated adults with office-defined grade 1 essential hypertension. Methods This single-center retrospective cross-sectional study enrolled 315 adults who underwent 24-h ambulatory blood pressure monitoring (ABPM) and transthoracic echocardiography within 7 days. BP dipping patterns were classified as dipper, non-dipper, reverse-dipper, or extreme-dipper. Continuous LARS was the primary outcome; low LARS (<35%) was the operational secondary outcome. The primary model was adjusted for age, sex, body mass index (BMI), 24-h SBP, fasting plasma glucose, natural-log-transformed triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and estimated glomerular filtration rate (eGFR). Results There were 126 dippers (40.0%), 124 non-dippers (39.4%), 45 reverse-dippers (14.3%), and 20 extreme-dippers (6.3%); 300 participants (95.2%) met ambulatory criteria for sustained hypertension, and 100 (31.7%) had low LARS. LARS differed across patterns (P < 0.001). Compared with dippers, non-dippers and reverse-dippers had lower adjusted LARS [β = −3.44, 95% confidence interval (CI) −4.68 to −2.20; β = −5.92, 95% CI −7.80 to −4.04] and higher odds of low LARS [non-dippers odds ratio (OR) = 3.68, 95% CI 1.83–7.39; reverse-dippers OR = 8.12, 95% CI 3.00–21.98; both P < 0.001]. Extreme-dipping was not associated with either outcome. When nighttime SBP replaced 24-h SBP, the associations were attenuated but remained statistically significant; the direction of association did not change in analyses restricted to participants with complete sleep diaries or sustained hypertension. Restricted cubic spline (RCS) analysis suggested nonlinearity. Conclusion Non-dipping and reverse-dipping BP patterns were associated with lower LARS and a higher likelihood of low LARS. Prospective multicenter studies are needed to determine prognostic and incremental clinical value.