Cost-effectiveness analysis of dopamine agonists in the treatment of Parkinson's disease in Japan.
BACKGROUND
Dopamine agonists such as bromocriptine or pergolide are often used in Japan to treat Parkinson's disease. Dopamine agonists are relatively expensive drugs; economic evaluations are required.


OBJECTIVE
To evaluate the cost effectiveness of dopamine agonists for the treatment of Parkinson's disease in Japan.


METHODS
We used a Markov model to simulate the course of Parkinson's disease and to compare the cost effectiveness of dopamine agonists added to levodopa with that of levodopa alone in Japan. The model assumed that 60-year-old men with Parkinson's disease in Hoehn-Yahr (HY) stages 2 to 5 using levodopa were administered dopamine agonists or continued on levodopa alone. The incremental cost effectiveness of dopamine agonists used for 10 years was then estimated.


METHODS
Societal.


RESULTS
In the patients in HY stage 2, the incremental cost effectiveness of dopamine agonists was 18,610,000 to 19,320,000 yen per quality-adjusted life-year (QALY) [$US 172,300 to $US 178,900/QALY; 1998 values] . In patients in HY stage 3 or higher, the use of dopamine agonists was dominant over levodopa alone mainly due to reduced cost for care. In sensitivity analyses, costs and effectiveness of dopamine agonists significantly influenced the results. The use of a generic formulation of bromocriptine was dominant over levodopa alone even in the patients with HY stage 2 disease.


CONCLUSIONS
Dopamine agonists appear to be cost effective in advanced Parkinson's disease, although their use is sensitive to the costs and effectiveness of dopamine agonists. If factors discouraging the prescription of generic drugs in Japan were removed, the treatment of Parkinson's disease would become more cost effective.
Shimbo
T
T
Department of General Medicine and Clinical Epidemiology, Graduate School of Medicine, Kyoto University, Japan. shimbot@kuhp.kyoto-u.ac-jp
Hira
K
K
Takemura
M
M
Fukui
T
T
D000368:Aged; D001971:Bromocriptine / Q000191:economics / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D018491:Dopamine Agonists / Q000191:economics / Q000627:therapeutic use*; D005260:Female; D006760:Hospitalization / Q000191:economics; D006801:Humans; D007564:Japan; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D010300:Parkinson Disease / Q000188:drug therapy* / Q000191:economics; D010479:Pergolide / Q000191:economics / Q000627:therapeutic use; D019057:Quality-Adjusted Life Years
D018491:Dopamine Agonists; D010479:Pergolide; D001971:Bromocriptine