The impact of reference pricing on switching behaviour and healthcare utilisation: the case of statins in Germany.

This paper analyses (1) the impact of the inclusion of statins in the German reference pricing scheme in 2005 on the statin market, and (2) the effect of switching behaviour subsequent to the policy change on healthcare utilisation and costs. Patients with prescriptions for statins in 2004 were observed for 1 year before and 1 year after the policy change, which went into effect on 1 January 2005. Data on outpatient and inpatient visits, pharmaceutical consumption, and cost to the sickness fund were collected from a sickness fund with more than 5.8 million insured members in 2005. Compared to patients who were not affected by the policy change, patients treated previously with atorvastatin experienced higher non-adherence and increased discontinuation of treatment (P < 0.0001). Compared to patients who continued treatment with atorvastatin (non-switchers), patients who switched to another statin were hospitalised more often (P = 0.0439). However, difference-in-differences in hospitalisation due to coronary heart disease (P = 0.8751) and emergency visits (P = 0.5624) did not differ significantly between the two groups. Patients who switched more than once experienced a significant increase in hospital visits (P = 0.0061) and hospital visits due to cardiovascular disease (P = 0.0096) compared to non-switchers. Difference-in-differences in outpatient healthcare utilisation did not differ between non-switchers and switchers. Total savings resulting from the policy change ranged from 94.4 million to 108.7 million. Although manufacturers usually comply with reference pricing by reducing their retail prices to the reference price, regulators have to be aware of the consequences in cases where manufacturers react as in this situation.