Improving Parkinson's Disease Care through Systematic Screening for Depression

Depression is common in Parkinson's disease (PD) but is underrecognized clinically. Although systematic screening is a recommended strategy to improve depression recognition in primary care practice, it has not been widely used in PD care.

The 15-item Geriatric Depression Scale (GDS-15) was implemented at 5 movement disorders clinics to screen PD patients. Sites developed processes suited to their clinical workflow. Qualitative interviews with clinicians and patients provided information on feasibility, acceptability, and perceived utility.

Prior to implementation, depression screening was recorded in 12% using a formal instrument; 64% were screened informally by clinical interview, and no screening was recorded in 24%. Of 1406 patients seen for follow-up care during the implementation period, 88% were screened, 59% using the GDS-15 (self-administered in 51% and interviewer administered in 8%), a nearly 5-fold increase in formal screening. Lack of clinician or staff time and inability to provide the GDS-15 to the patient ahead of the visit were the most commonly cited reasons for lack of screening using the GDS-15; 378 (45%) patients completing the GDS-15 screened positive for depression, and 137 were enrolled for a 12-month prospective follow-up. Mean GDS-15 scores improved from 8.8 to 7.0 (P < 0.0001) and the 39-item Parkinson's Disease Questionnaire emotional subscore from 42.2 to 36.7 (P = 0.0007).

Depression screening in PD using a formal instrument can be achieved at much higher levels than is currently practiced, but there are barriers to implementing this in clinical practice. An individual site-specific process is necessary to optimize screening rates.