Does prior authorization of sibutramine improve medication compliance or weight loss?

This study was designed to examine whether prior authorization for insurer reimbursement of weight loss medication affects compliance with taking sibutramine or adherence to a medical weight control program. The underlying hypothesis is that physician advocacy through prior authorization increases patient compliance and treatment outcomes.

A retrospective review was conducted of 22 subjects who had received a prescription for sibutramine that was reimbursed through their health insurer by prior authorization (PAR) and compared them with 47 randomly selected subjects who were also prescribed sibutramine but did not receive reimbursement (non-PAR). Outcome measures included the percentage weight lost, visits to the clinic, and number of prescriptions received at 3, 6, 9, and 12 months.

The proportion of subjects remaining in the clinic program, the number of clinic visits made, the number of prescriptions received, and the amount of weight lost were all significantly greater among PAR subjects than among non-PAR subjects. PAR subjects used the medication 37% longer by month 6 (2.43 vs. 1.52 prescriptions; p<0.02), visited the clinic 44% more often (72.5 vs. 40.5 visits in 12 months; p<0.0006), and achieved 38% better maximal weight loss (16% vs. 9.9% at 6 months; p<0.49) than non-PAR subjects.

This study suggests that, when those medications are not included on a health insurer's formulary, the use of the prior authorization process may improve both medication and behavioral compliance.