Deep brain stimulation in the treatment of Parkinson's disease: a cost-effectiveness analysis.
BACKGROUND
In treating PD, deep brain stimulation (DBS) has shown great promise in a series of uncontrolled studies.


OBJECTIVE
To estimate the incremental cost effectiveness of DBS compared with the best medical management in late-stage PD.


METHODS
The authors constructed a decision model to determine the lifetime incremental cost effectiveness between two options in patients with PD aged 50 years and older: 1) best medical management and 2) DBS. As the long-term efficacy of DBS (>3 years) is not known, key assumptions regarding the procedure's long-term durability were made. Costs were in US 2000 dollars, and quality-adjusted life year (QALY) was the effectiveness measure. Base assumptions were that quality of life (QOL) in patients with late-stage PD is 0.55 (0-to-1 scale, 1 is perfect health) and that DBS benefits are constant for 4 years, eroding gradually over the next 5 years until at parity with those produced by best medical management. Incremental cost-effectiveness and sensitivity analyses were performed.


RESULTS
Under base-case assumptions, DBS provides an additional 0.72 QALY at an additional cost of $35,000 compared with best medical management that results in an incremental cost-effectiveness ratio (C/E) of $49,000. QOL increases of between 18 and 30% resulted in questionable cost effectiveness. QOL increases of between 6 and 18% resulted in incremental C/E ratios not usually considered cost effective (>100,000/QALY).


CONCLUSIONS
The results suggest that DBS may be cost effective in treating PD if QOL improves 18% or more compared with those receiving best medical management. This underscores the need for randomized, controlled, prospective DBS experiments including QOL and economic components.
Tomaszewski
K J
KJ
Department of Community and Preventive Medicine, University of Rochester School of Medicine, NY 14642, USA. kenneth_tomaszewski@urmc.rochester.edu
Holloway
R G
RG
D000368:Aged; D003362:Cost-Benefit Analysis / Q000379:methods; D003661:Decision Support Techniques; D004599:Electric Stimulation Therapy / Q000191:economics*; D006801:Humans; D008875:Middle Aged; D018803:Models, Economic; D010300:Parkinson Disease / Q000188:drug therapy / Q000191:economics* / Q000628:therapy; D011788:Quality of Life