Health Behaviors, Nocturnal Hypertension, and Non-dipping Blood Pressure: The Coronary Artery Risk Development in Young Adults and Jackson Heart Study.

Background: Several health behaviors have been associated with hypertension based on clinic blood pressure (BP). Data on the association of health behaviors with nocturnal hypertension and non-dipping systolic BP (SBP) are limited.

Methods: We analyzed data for participants with ambulatory BP monitoring at the Year 30 Coronary Artery Risk Development in Young Adults (CARDIA) study exam in 2015-2016 (n = 781) and the baseline Jackson Heart Study (JHS) exam in 2000-2004 (n = 1,046). Health behaviors (i.e., body mass index, physical activity, smoking, and alcohol intake) were categorized as good, fair, and poor and assigned scores of 2, 1, and 0, respectively. A composite health behavior score was calculated as their sum and categorized as very good (score range = 6-8), good (5), fair (4), and poor (0-3). Nocturnal hypertension was defined as mean asleep SBP ≥ 120 mm Hg or mean asleep diastolic BP ≥ 70 mm Hg and non-dipping SBP as < 10% awake-to-asleep decline in SBP.

Results: Among CARDIA study and JHS participants, 41.1% and 56.9% had nocturnal hypertension, respectively, and 32.4% and 72.8% had non-dipping SBP, respectively. The multivariable-adjusted prevalence ratios (95% confidence interval) for nocturnal hypertension associated with good, fair, and poor vs. very good health behavior scores were 1.03 (0.82-1.29), 0.98 (0.79-1.22), and 0.96 (0.77-1.20), respectively in CARDIA study and 0.98 (0.87-1.10), 0.96 (0.86-1.09), and 0.86 (0.74-1.00), respectively in JHS. The health behavior score was not associated non-dipping SBP in CARDIA study or JHS after multivariable adjustment.

Conclusions: A health behavior score was not associated with nocturnal hypertension or non-dipping SBP.