Treatment Patterns and Predictive Factors Among Older Adults With Comorbid Parkinson Disease and Depression

Research focused on treatment patterns and predictive factors suggests that older adults with polypharmacy in the US may be more likely to receive treatment while those with comorbid chronic conditions are less likely, suggesting that treatment options for this population are underutilized in clinical practice. 

Depression is a common nonmotor symptom of Parkinson disease (PD), with high prevalence and a negative impact on quality of life. Treatment for depression in PD is often inadequate or ineffective, with limited studies on treatment patterns and predictors among older adults in the US. Therefore, this cross-sectional study aims to assess the patterns and predictors of depression treatment in older adults with PD seeking ambulatory care in the US. 

The study included data from 2005 to 2011 from the National Ambulatory Medical Care Survey (NAMCS) and the outpatient department (OPD) of the National Hospital Ambulatory Medical Care Survey (NHAMCS). These sources use a multistage probability design for data collection, involving the selection of samples from primary sampling units (PSUs). The samples include practicing physicians from each PSU and patient visits from their yearly practices. The data collection process for NHAMCS is similar to that of NAMCS, with the OPD portion of NHAMCS used for this study due to the similarity of medical care provided in OPD and office-based settings. 

The study included visits made by adults 65 years old or older with PD and depression. PD was diagnosed using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code 332.xx, while depression was identified based on the positive response to the question regarding the patient's current depressive state. Depression treatment was defined as antidepressant use with or without psychotherapy and antidepressant use was determined using generic drug codes and Multum Lexicon Codes.  

Data analysis reveals that 9.3 million ambulatory visits recorded a PD diagnosis, with 1.7 million of those also having a concurrent depression diagnosis. The characteristics of the study sample included mostly individuals aged 75 years and older, men, and White individuals residing in metropolitan areas and with government insurance. Most visits were in physician/clinic specialties other than general and family practice, and patients were typically already established with the physician/clinic.  

The study found that 57.63% of the visits received depression treatment, with SSRIs being the most prescribed class of antidepressants. Men were less likely than women to receive depression treatment, while those with dPD and polypharmacy were more likely, and those with comorbid chronic conditions were less likely to receive treatment. 

“Approximately six out of ten older adults in the US with PD and depression received depression treatment. SSRIs were most frequently prescribed, and gender, number of medications prescribed during visit, and number of chronic conditions were significantly associated with depression treatment among older adults with dPD,” said researchers. “Future real-world long-term studies should investigate health outcomes associated with depression treatment in this vulnerable population.”  

Reference  

Bhattacharjee S, Vadiei N, Goldstone L, et al. Patterns and predictors of depression treatment among older adults with Parkinson's disease and depression in ambulatory care settings in the United States. Parkinson's Disease. 2018;3402983. doi:10.1155/2018/3402983