Higher pretreatment blood pressure is associated with greater alcohol drinking reduction in alcohol-dependent individuals treated with doxazosin

- Research suggests the α1 receptor agonists reduces alcohol consumption.
- Pre-treatment blood pressure (BP) predicts therapeutic response of prazosin in Post-Traumatic Stress Disorder (PTSD) patients.
- Doxazosin reduced alcohol consumption in alcohol-dependent (AD) patients with a high family history density of alcoholism (FHDA).

BackgroundPreclinical and clinical research suggest that the α1 receptor antagonist prazosin reduces alcohol consumption. Furthermore, clinical studies indicate a role for prazosin in treating Post-Traumatic Stress Disorder (PTSD) symptoms and a recent trial suggested that pre-treatment blood pressure (BP) predicts therapeutic response for prazosin in PTSD patients. Whether pre-treatment BP may predict response to α1 blockers in alcohol-dependent (AD) patients is unknown. We previously reported a randomized controlled trial (RCT) where doxazosin, an α1 receptor antagonist with a more favorable pharmacokinetic profile than prazosin, reduced drinks per week (DPW) and heavy drinking days (HDD) in AD patients with a high family history density of alcoholism. In this study, we tested pre-treatment BP as another potentially valuable clinical moderator of doxazosin's response on alcohol consumption.MethodsThis was a double-blind placebo-controlled RCT testing doxazosin up to 16 mg/day in AD treatment-seeking patients (N = 41). The hypothesized moderator effect of baseline standing systolic and diastolic BP on DPW and HDD was tested.ResultsWith pre-treatment standing diastolic BP as a moderator, there were significant BP x medication interactions for both DPW [**p = 0.009, d = 0.80] and HDD [*p = 0.018, d = 1.11]. Post-hoc analyses indicated significant doxazosin effects in patients with higher standing BP in reducing both DPW and HDD.ConclusionThese findings suggest that higher standing diastolic BP at baseline (pre-treatment) may represent a predictor of doxazosin's response on alcohol consumption in AD patients. These results further elucidate the possible efficacy and mechanisms of action of α1 receptor antagonism in AD individuals.