Basson MD, et al. - This study was undertaken to explore how calcium channel blockers (CCB) affect blood pressure variability (BPV) progression and whether long- term adverse effects of BPV differ after CCB treatment than after treatment with other antihypertensives. Researchers retrospectively examined 25,268 US veterans who had been followed for three years without hypertensive therapy, started on a single class of anti-hypertensive agents (thiazides, calcium channel blockers, ACE inhibitors, or beta blockers), treated for six years, and then followed for three additional years. They estimated BPV as standard deviation of systolic or diastolic blood pressures from at least 10 measurements over each three-year period. The results of this study demonstrate that possible deleterious effects of thiazides should be considered within the context of the study population, who were mostly male and received only a single class of hypertensives. This research does not support choosing CCB over other agents specifically to lessen BPV-associated risk while CCB may ameliorate BPV over time.