This randomized controlled trial will examine whether behavioral neurocardiac training with heart rate variability biofeedback (BNT) augments reduction in ambulatory daytime and 24-hour SBP, DBP and PP, in comparison to an active control intervention (AC, autogenic relaxation training), among subjects diagnosed with hypertension, and following adjustment for medications. In addition, the independent association between the BNT and AC interventions on vagal-heart rate modulation and baroreflex sensitivity will be evaluated during a standardized assessment protocol of mental stress testing. This study extends a previous trial conducted at the UHN, in which we reported that the biofeedback intervention independently augments vagal-heart rate modulation, while reducing symptoms of stress and depressed mood, among subjects diagnosed with cardiovascular disease. Exploratory features of this trial will examine the association between ambulatory blood pressure, vagal-heart rate modulation, baroreflex sensitivity, and markers of inflammatory activity.

Inclusion criteria:

• 35 to 64 years of age
• diagnosis of Grade 1 or 2 hypertension (140-159 mmHg or 160-180 mmHg SBP; or 90-99 or 100-110 mmHg DBP, respectively).
• among subjects not prescribed medication, hypertension confirmed by ambulatory BP monitoring: mean 24-hour SBP > 130 mmHg or DBP > 80 mmHg.
• subjects prescribed antihypertensive pharmacotherapy are required to have a treatment regimen that was unchanged for at least 4 months prior to enrollment.

Exclusion criteria:

• diagnosis of cardiovascular disease, clinically significant arrhythmia, sleep disorder, psychiatric illness (eg. psychosis), alcohol/drug dependence within the previous year, or an inability to comprehend English or French