Impact of formulary policy on thiazolidinedione (TZD) use in the ontario drug benefit (ODB) program

Abstract

Intro The ODB formulary policy is very restrictive for TZD use, limiting reimbursement for second line use that must be documented in an individualized request from the prescribing physician. This study was designed to determine if patients receiving the drug met the required reimbursement criteria and whether the policy resulted in preventing appropriate patients from receiving a TZD. Methods ODB eligible type 2 DM patients using an oral hypoglycaemic drug were recruited through community pharmacies. Patients were interviewed using computer assisted telephone interviewing software with trained interviewers. Patient chart information was obtained from their physicians via a fax-back form. Results 249 patients were recruited. Mean (sd) age was 75(5) years, with 10.5 (8) years duration of DM, BMI 27.6 (5) and HgA1c 0.07 (0.01).). Hypertension prevalence 80%, hyperlipidemia 74%, cardiovascular disease 46%. 85% of TZD users had previously tried or were still using other oral hypoglycaemic drugs. Patients using a TZD were more likely to have used a diabetic clinic, had a history of an adverse effect with a non-TZD oral hypoglycaemic drug and had a greater household income than non TZD users. Conclusions The inability to access a diabetic clinic and limited household income may prevent patients who might benefit from a TZD from receiving these drugs. While restrictive formulary policies can prevent undesirable or inappropriate drug use they may prevent appropriate access as well. Clinical Pharmacology & Therapeutics (2005) 77, P72–P72; doi: 10.1016/j.clpt.2004.12.165