Diffusion of innovations: treatment of Alzheimer's disease in Germany

Abstract

Systematic barriers seem to slow down the market penetration of innovative acethylcholinesterase (AChE) inhibitors in Alzheimer's disease. The goal of our study was to examine the diffusion of AChE inhibitors into the German market in more detail. On the basis of using the ongoing surveillance panel of the Institute of Medical Statistic (IMS) Health, the prescription patterns of 100 physicians (72 general practitioners, 28 neurologists) were examined. In addition, structured telephone interviews with the same 100 physicians were conducted. The interview included the assessment of a hypothetical treatment situation (i.e. physicians were asked what they would prescribe if a close relative of theirs had Alzheimer's disease) as well as qualitative items examining the physicians’ attitudes towards AChE inhibitors and the perceived impact on drug budgets. As a major result, the analysis revealed that neurologists prescribed AChE inhibitors to 44.6% of their patients, while general practitioners only treated 9.0% of their patients with AChE inhibitors. The analysis of the qualitative items revealed positive attitudes regarding the safety and efficacy of AChE inhibitors, but negative attitudes regarding the budgetary limitations to prescribing these drugs. A correlation of r=0.21 (P<0.05) was found between the perceived impact on drug budgets and the adoption of AChE inhibitors and a correlation of r=0.32 (P<0.002) was seen between the physician's specialty and the adoption of AChE inhibitors. These data show that, while the AChE inhibitor adoption process has passed the early stages, various barriers slow down the final stages of AChE inhibitor adoption. The drug budget in particular seems to inhibit the adoption of the innovation by the majority of general practitioners. This leads to a more short-term cost control strategy instead of long-term disease management and cost saving approaches.

Introduction

Due to a continuous increase in life expectancy, Alzheimer's disease has become a major issue in most Western societies. Effective treatment options were unavailable until the introduction of an innovative new class of drugs, the acethylcholinesterase (AChE) inhibitors, in the mid 1990s. The respective market approval dates in Germany were August 1997 for Donepezil [1] and May 1998 for Rivastigmine [2], [3]. Despite the recommendation in various national and international guidelines to use AChE inhibitors, [4], [5] the German market was relatively slow to adopt the AChE inhibitors. Available data indicate that, in 2000, many patients continued to claim that their physicians withheld drugs from them [6].

Most available theoretical frameworks for the dissemination and implementation of medical guidelines [7] heavily rely on Roger's ‘Diffusion of Innovations Theory’ [8]. According to Roger, new ideas are adopted very slowly during the early stages of the diffusion process. If the innovation is perceived as advantageous by its early adopters, however, the rate of adoption steadily increases, resulting in an S-shaped rate of adoption of the innovation over time. The slope of the adoption curve is determined by important characteristics, such as the superiority of the innovation over its predecessor (‘relative advantage’) or its compatibility with the current approach in the system (‘compatibility’).

Systematic barriers seem to exist that slow down the market penetration of AChE inhibitors in Alzheimer's disease. Recently published data from the UK indicate that only 142 out of ≈3500 patients in Leeds received treatment with AChE inhibitors [9]. According to the authors, the slow adoption may be due to concerns about cost, lack of resources and a great number of undetected cases of Alzheimer's disease.

The goal of our study was to examine the diffusion of AChE inhibitors into the German market in more detail. In particular, we focused on the different roles of neurologists and general practitioners, with the former acting as early adopters and the latter as the ‘early and late majority’ of adopters. Furthermore, we investigated the negative effect of drug budgets on the diffusion of innovations.