No significant differences in the critical outcome were found for the comparisons of ACEIs and CCBs or ARBs and CCBs. This does not imply equivalency, only that a conclusion could not be determined. No critical outcomes were noted for ARBs versus thiazide-type diuretics.[135] The Work Group did not make a formal recommendation for other outcomes such as stroke or heart failure reduction alone. However, there were an extensive number of comparisons that addressed other outcomes. Notable findings were that thiazide-type diuretics were superior to the other drug classes for preventing CHF outcomes, CCBs were superior to the other drug classes for reducing all-cause mortality, and CCBs were inferior to other drug classes at preventing CHF outcomes.[135] ACEIs and ARBs are not used concomitantly, due to well-recognized safety risks, as discussed in Recommendation 26. Although the evidence was not supportive of a recommendation, providers can consider beta blockers as an alternative to the four main antihypertensive classes for patients with compelling indications, including those with underlying CAD, following MI, and in heart failure with reduced ejection fraction. Patients who are intolerant to the four main antihypertensive drug classes may also consider a beta blocker. The SR found beta blockers were equivalent to ARBs for the composite cardiovascular outcomes and reported no significant difference between beta blockers and CCBs or thiazide-type diuretics. There were no critical outcomes reported for beta blockers compared to ACEIs. Some important outcomes showed beta blockers were inferior to the other drugs classes, particularly for stroke reduction.[135] Beta blockers are not recommended as initial antihypertensive therapy, as the evidence is mixed as to whether there is a clear benefit in reducing cardiovascular events. Thomopoulos et al. (2015) did not evaluate differences in adverse events.