First-line drugs for hypertension

David Spence misses the point of the series of 3 articles in suggesting that they are about cost.1^,2^,3 These articles systematically review the best available evidence from randomized controlled trials using a hierarchy of evidence; cost is the least and last consideration. The clear conclusion from the available evidence, independent of cost, is that thiazides are the best first-choice drugs. In other words, if thiazides were the most expensive antihypertensive drug class, the conclusion would be the same.

Spence inaccurately implies that the evidence in these articles is biased. It is true that I am the Managing Director of the BC Therapeutics Initiative. However, he does not understand the relationship between the Therapeutics Initiative and BC Pharmacare. The Therapeutics Initiative assesses evidence of the efficacy and safety of new and existing drugs and provides a summary of that evidence to Pharmacare. The Therapeutics Initiative does not consider or include cost in that assessment. Evaluation of cost and cost- effectiveness evidence is the mandate of the Pharmacoeconomics Initiative. The Drug Benefit Committee of Pharmacare and the Director of Pharamacare make funding decisions on the basis of summaries of evidence (not funding advice) from the Therapeutics Initiative and Pharmacoeconomics Initiative plus other considerations.

Spence is asking us to put aside evidence from randomized controlled trials and in its place accept the conclusion from 2 retrospective observational studies.4^,5 Both of these studies were funded by the drug industry and the conclusions ratified their vested interest. In my opinion, this type of study reflects the profound influence drug companies can have on measures of drug compliance that rely on dispensed medication. The industry accomplishes this by providing drug samples (not detectable as dispensed medication) and intensive one-on-one promotion to physicians. Answering whether medication persistence differs with different drugs necessitates randomization of patients to the alternate drugs and blinding of both physicians and patients.