Relative mortality in U.S. Medicare beneficiaries with Parkinson disease and hip and pelvic fractures

Assessing and managing bone health and fracture risk in Parkinson's disease: the BONE PARK 2 protocol

BACKGROUND

In Parkinson's disease (PD), the propensity to fall and the higher risk of osteoporosis converge yielding a high fracture risk. Updated National Osteoporosis Guideline Group (NOGG) guidance recommends that PD should trigger a risk assessment, for example using the FRAX tool, yet clinical pathways remain sub-optimal. To address this, we generated an algorithm for the assessment and management of bone health specifically in PD.

METHODS

Within the Proactive and Integrated Management and Empowerment in Parkinson's Disease randomised controlled trial (PRIME-UK RCT), bone-health metrics were collected, and all participants were offered a dual X-ray absorptiometry scan. The FRAX tool was used to obtain the 10-year probability of hip and major osteoporotic fracture (MOF), and the resulting NOGG risk-category recorded. Probabilities were recalculated including femoral-neck bone mineral density (FN-BMD) and/or with numeric adjustment for recurrent falls, and results compared.

RESULTS

Among 182 people with parkinsonism (mean age 73.8 years, 65% male, median disease duration 5 years), 28% reported a prior fragility fracture, and 40.7% recurrent falls over the previous year. 28.6% had MOF above NOGG intervention thresholds (IT); whilst 12.1% had a FN-BMD T-Score ≤ -2.5. Recalculation of FRAX with FN-BMD (n = 182) reduced fracture MOF and hip fracture probabilities; 12 (6.6%) deescalated below the IT, and 16 (8.8%) moved above the IT.

CONCLUSIONS

This 2024 BONE-PARK algorithm is informed by both the latest NOGG Guidelines and novel findings in a 'real-world' population. The algorithm will aid bone health assessment for people with PD.

Management of Osteoporosis in Parkinson's Disease: A Systematic Review of Clinical Practice Guidelines

BACKGROUND

Parkinson's disease (PD) is the fastest-growing neurological disorder globally. Defining features include tremor, muscular rigidity, bradykinesia, and postural instability, which in combination with nonmotor symptoms such as cognitive impairment and orthostatic hypotension increase the risk of falls. Along with low bone mineral density, fracture risk is high in PD.

OBJECTIVES

The aims were to identify and appraise clinical practice guidelines, consensus statements, and treatment algorithms containing recommendations for bone health in people with PD (PwP).

METHODS

We systematically searched 4 electroninc databases (MEDLINE, Embase, Emcare, and Web of Science) (n = 78), in addition to the websites of organizations, societies, and professional bodies focused on PD or osteoporosis (n = 28), up to April 22, 2024.

RESULTS

After duplicate removal, screening, and full-text review, 6 records were included. Included records were appraised using the AGREE II (Appraisal of Guidelines for Research and Evaluation) tool. All records recognized bone health as a concern in PD, yet recommendations for fracture-risk screening were inconsistent. Two of six records grouped PD under the broad category of neurological diseases. The acceptability and tolerance of anti-osteoporosis medications in PwP was discussed only in 1 record, which incorporated national osteoporosis guidelines into a PD-specific treatment algorithm.

CONCLUSIONS

This review highlights that despite the documented high fracture rates of PwP, health professionals do not always have adequate resources to support them when considering how to manage osteoporosis. Osteoporosis screening and management needs to be incorporated into PD treatment guidelines, and equally providing specific recommendations for PwP related to bone health in national osteoporosis guidelines should be a priority given the high burden of fracture in the patient population.

Ethnicity and Parkinson's Disease: Motor and Nonmotor Features and Disease Progression in Latino Patients Living in Rural California

BACKGROUND

Parkinson's disease (PD) is the second most common neurodegenerative disorder among older adults worldwide. Currently, studies of PD progression rely primarily on White non-Latino (WNL) patients. Here, we compare clinical profiles and PD progression in Latino and WNL patients enrolled in a community-based study in rural Central California.

METHOD

PD patients within 5 years of diagnosis were identified from 3 counties between 2001 and 2015. During up to 3 visits, participants were examined by movement disorders specialists and interviewed. We analyzed cross-sectional differences in PD clinical features severity at each study visit and used linear mixed models and Cox proportional hazards models to compare motor, nonmotor, and disability progression longitudinally and to assess time to death in Latinos compared to WNL patients.

RESULTS

Of 775 patients included, 138 (18%) self-identified as Latino and presented with earlier age at diagnosis (63.6 vs 68.9) and death (78.6 vs 81.5) than WNL. Motor (hazard ratio [HR] = 1.17 [0.71, 1.94]) and nonmotor symptoms did not progress faster in Latino versus WNL patients after accounting for differences in baseline symptom severity. However, Latino patients progressed to disability stages according to Hoehn and Yahr faster than WNL (HR = 1.81 [1.11, 2.96]). Motor and nonmotor symptoms in Latino patients were also medically managed less well than in WNL.

CONCLUSIONS

Our PD study with a large proportion of Latino enrollees and progression data reveals disparities in clinical features and progression by ethnicity that may reflect healthcare access and structural socioeconomic disadvantages in Latino patients with PD.

Mortality of Deep Brain Stimulation and Risk Factors in Patients With Parkinson's Disease: A National Cohort Study in Korea

BACKGROUND

This study aimed to investigate 1) long-term outcomes of deep brain stimulation (DBS), such as mortality after DBS as well as the causes of death, 2) demographic and socioeconomic factors influencing mortality, and 3) comorbidities affecting mortality after DBS in patients with Parkinson's disease (PD).

METHODS

This study analyzed the National Health Insurance Service-National Health Information Database. Data on patients with PD diagnosis codes from 2002 to 2019 were extracted and analyzed. Data on the causes of death were obtained by linking the causes of death to data from Statistics Korea. The Kaplan-Meier method with the log-rank test was used for survival analysis. Multivariate Cox regression analyses were used to estimate hazard ratios (HRs) and their 95% confidence intervals. Regarding comorbidities such as PD dementia and fracture, which did not satisfy the assumption for the proportional HR, time-dependent Cox analysis with the Mantel-Byar method was used.

RESULTS

From 2005 to 2017, among 156,875 patients diagnosed with PD in Korea, 1,079 patients underwent DBS surgery, and 251 (23.3%) had died by 2019. The most common cause of death (47.1%) was PD. In the multivariate Cox regression analysis, the higher the age at diagnosis and surgery, the higher the mortality rate. The men and medical aid groups had significantly higher mortality rates. PD dementia and fracture were identified as risk factors for mortality.

CONCLUSION

Older age at diagnosis and surgery, being male, the use of medical aid, and the comorbidity of dementia and fractures were associated with a higher risk of mortality after DBS in patients with PD. Neurologists should consider these risk factors in assessing the prognosis of PD patients undergoing DBS.

Postoperative complications, mortality, and quality of in-hospital care among hip fracture patients with Parkinson's disease

AIM

The aim of this study was to investigate the association between Parkinson's disease (PD) and postoperative complications, mortality, and quality of in-hospital care in patients with hip fracture.

METHODS

We included patients aged 65+ years with an incident hip fracture from 2004-2017, registered in the Danish Multidisciplinary Hip Fracture Registry. Patients with PD were identified using diagnosis codes prior to hip fracture. Using log-binomial regression, we calculated both 30-day crude and adjusted risk ratios (aRR) with 95% confidence intervals (CIs) for the following outcomes: any hospital-treated infections, pneumonia, urinary tract infection, sepsis, community-treated infections, cardiovascular events, mortality, and fulfilment of quality indicators of in-hospital care. Analyses were adjusted for age, sex and Charlson comorbidity index score.

RESULTS

We identified 77,550 hip fracture patients of which 1,915 had PD. Compared to non-PD, patients with PD had higher risk of any hospital-treated - (aRR = 1.27 (CI: 1.10-1.45) and community-treated infection (aRR = 1.22 (CI: 1.13-1.32)), pneumonia (aRR = 1.38 (1.11-1.69)), urinary tract infection (aRR of 1.58 (CI: 1.28-1.92)) and sepsis (aRR = 1.18 (CI: 0.67-1.89)), but a reduced risk of cardiovascular events (aRR = 0.59 (CI: 0.41-0.82)). The aRR for 30-day mortality was 1.11 (CI: 0.97-1.27) for PD vs non-PD patients, and the aHR for 1-year mortality was 1.19 (CI: 1.09-1.30). The aRRs for fulfillment of all relevant quality indicators was about 1 for PD vs non-PD patients.

CONCLUSION

Hip fracture patients with PD have a higher risk of infections and mortality within 30 days after surgery after adjustment for sex, age, and comorbidity. They do, however, receive comparable quality of in-hospital care after hip fracture compared to non-PD patients.

Rate of Hospitalizations and Underlying Reasons Among People with Parkinson's Disease: Population-Based Cohort Study in UK Primary Care

BACKGROUND

Hospitalization in Parkinson's disease (PD) is associated with reduced quality of life, caregiver burden and high costs. However, no large-scale studies of rate and causes of hospitalizations in patients with PD have been published.

OBJECTIVE

To investigate the rate and reasons for hospitalization and factors associated with hospitalization among people with PD compared to the general population.

METHODS

We examined rate and causes of admission in PD patients and matched controls in The Health Improvement Network from 2006 to 2016. Multivariable Poisson regression was used to explore the effects of age, gender, social deprivation, urbanicity and practice geographic location on hospitalization.

RESULTS

In the longitudinal data from 9,998 newly diagnosed individuals with PD and 55,554 controls without PD aged ≥50 years, 39% of PD patients and 28% of controls were hospitalised over a median follow-up of 5.1 years. The adjusted incidence rate ratio (IRR) of hospitalization in PD compared to controls was 1.33 (95% CI:1.29-1.37) and rose with increased follow-up duration. Hospitalization rate was overall higher in the older age groups, but the adjusted IRR of hospitalization compared to controls was highest in the youngest age group. PD patients were more often admitted with falls/fractures, infections, gastrointestinal complications, PD, dementia, psychosis/hallucinations, postural hypotension, electrolyte disturbances, stroke and surgical procedures and slightly less often due to hypertension.

CONCLUSION

People with PD have an increased hospitalization rate compared to controls, particularly in the younger age groups, and it increases with longer disease duration. The complications of motor and non-motor features of PD are amongst the main reasons for admission, some of which could be managed preventatively to avoid admissions.

Evaluating Oculomotor Tests before and after Vestibular Rehabilitation in Patients with Parkinson’s Disease: A Pilot Pre-Post Study

Introduction. The elderly population is commonly affected by balance and gait disorders that increase the risk of falls. Pivotal systems for efficient postural control are sensory, motor, visual, vestibular, and cognitive. Disruption in any of these systems could lead to postural instability. Vestibular rehabilitation is a set of exercises that positively affect the primary components of the central sensory-motor integration, including somatosensory, visual, and vestibular systems. Accordingly, we hypothesized that vestibular rehabilitation exercises might improve both oculomotor functions and upright postural control in patients with Parkinson’s disease. Materials and Methods. 11 idiopathic Parkinson’s patients voluntarily participated in this study based on inclusion criteria: central vestibular dysfunction and the Hoehn and Yahr scale scores less than or equal to 3. Videonystagmography (VNG) and the Berg Balance Scale (BBS) scores were measured at the baseline. Then, the patients underwent vestibular rehabilitation training for 24 sessions (3 sessions per week). The VNG and BBS were measured again after 48 hours of the completion of the last session of the training. Result. After completing vestibular rehabilitation sessions, there were significant improvements in balance $\left(P\le 0.001\right)$ . Eye-tracking and gaze function statistically improved in 7 patients and 6 patients, respectively. Conclusion. Vestibular rehabilitation produced positive effects on oculomotor function and balance in a small cohort of people with PD. Consequently, it could be considered as a possible effective intervention for Parkinson’s patients. This trial is registered with IRCT201709123551N6.

Access and Attitudes Toward Palliative Care Among Movement Disorders Clinicians

BACKGROUND

Neuropalliative care is an emerging field for those with neurodegenerative illnesses, but access to neuropalliative care remains limited.

OBJECTIVE

We sought to determine Movement Disorder Society (MDS) members' attitudes and access to palliative care.

METHODS

A quantitative and qualitative survey instrument was developed by the MDS Palliative Care Task Force and e-mailed to all members for completion. Descriptive statistics and qualitative analysis were triangulated.

RESULTS

Of 6442 members contacted, 652 completed the survey. Completed surveys indicating country of the respondent overwhelmingly represented middle- and high-income countries. Government-funded homecare was available to 54% of respondents based on patient need, 25% limited access, and 21% during hospitalization or an acute defined event. Eighty-nine percent worked in multidisciplinary teams. The majority endorsed trigger-based referrals to palliative care (75.5%), while 24.5% indicated any time after diagnosis was appropriate. Although 66% referred patients to palliative care, 34% did not refer patients. Barriers were identified by 68% of respondents, the most significant being available workforce, financial support for palliative care, and perceived knowledge of palliative care physicians specific to movement disorders. Of 499 respondents indicating their training in palliative care or desire to learn these skills, 55% indicated a desire to gain more skills.

CONCLUSIONS

The majority of MDS member respondents endorsed a role for palliative care in movement disorders. Many members have palliative training or collaborate with palliative care physicians. Although significant barriers exist to access palliative care, the desire to gain more skills and education on palliative care is an opportunity for professional development within the MDS. © 2021 International Parkinson and Movement Disorder Society.

α4β2* Nicotinic Cholinergic Receptor Target Engagement in Parkinson Disease Gait-Balance Disorders

OBJECTIVE

Attentional deficits following degeneration of brain cholinergic systems contribute to gait-balance deficits in Parkinson disease (PD). As a step toward assessing whether α4β2* nicotinic acetylcholine receptor (nAChR) stimulation improves gait-balance function, we assessed target engagement of the α4β2* nAChR partial agonist varenicline.

METHODS

Nondemented PD participants with cholinergic deficits were identified with [¹⁸ F]fluoroethoxybenzovesamicol positron emission tomography (PET). α4β2* nAChR occupancy after subacute oral varenicline treatment was measured with [¹⁸ F]flubatine PET. With a dose selected from the nAChR occupancy experiment, varenicline effects on gait, balance, and cognition were assessed in a double-masked placebo-controlled crossover study. Primary endpoints were normal pace gait speed and a measure of postural stability.

RESULTS

Varenicline doses (0.25mg per day, 0.25mg twice daily [b.i.d.], 0.5mg b.i.d., and 1.0mg b.i.d.) produced 60 to 70% receptor occupancy. We selected 0.5mg orally b.i.d for the crossover study. Thirty-three participants completed the crossover study with excellent tolerability. Varenicline had no significant impact on the postural stability measure and caused slower normal pace gait speed. Varenicline narrowed the difference in normal pace gait speed between dual task and no dual task gait conditions, reduced dual task cost, and improved sustained attention test performance. We obtained identical conclusions in 28 participants with treatment compliance confirmed by plasma varenicline measurements.

INTERPRETATION

Varenicline occupied α4β2* nicotinic acetylcholine receptors, was tolerated well, enhanced attention, and altered gait performance. These results are consistent with target engagement. α4β2* agonists may be worth further evaluation for mitigation of gait and balance disorders in PD. ANN NEUROL 2021;90:130-142.

Ethnic Variation in the Manifestation of Parkinson's Disease: A Narrative Review

The global prevalence of Parkinson's disease is increasing, yet the characteristics, risk factors and genetics of PD in Black, Asian and Hispanic populations is little understood. In this paper we review the published literature on clinical variation in the symptoms and signs of Parkinson's disease in different ethnic groups and responses to treatment. We included any study that sampled patients with Parkinson's disease from distinct ethnic backgrounds. We conclude that whilst there is little published evidence for ethnic variation in the clinical features of Parkinson's disease, there are substantial limitations and gaps in the current literature, which mean that the evidence does necessarily not fit with clinical observation. Possible explanations for expected differences in manifestation include genetic determinants, the co-existence of cerebrovascular disease and/or Alzheimer's disease pathology, healthcare inequalities and socio-cultural factors.

Hip Fracture in Patients with Parkinson's Disease and Related Mortality: A Population-Based Study in Korea

INTRODUCTION

Patients with Parkinson's disease (PD) are prone to falls, thereby increasing the risk of fractures and mortality. This population-based study investigated the risk of hip fractures and their effect on mortality in patients with PD in Korea.

METHODS

National Health Insurance Service-National Sample Cohort data were used. Patients newly diagnosed with PD between 2006 and 2015 and age- and sex-matched individuals were classified into the PD group and the comparison group, respectively, with a 1:9 ratio. The Cox proportional hazards model was used to calculate hazard ratios (HRs), and the Kaplan-Meier method to identify survivorship.

RESULTS

In total, 26,570 individuals were enrolled in the study: 2,657 in the PD cohort and 23,913 in the matched comparison cohort. The PD group had about a 2 times higher risk of hip fracture than the comparison group (3.95 vs. 1.94%, p < 0.001). According to sex, the difference between the PD and comparison groups for the risk of hip fracture was greater in males than in females. The highest difference in HR for hip fracture between the PD and comparison groups was found in individuals aged between 60 and 69 years. Regarding post-fracture mortality in patients with PD, the mortality risk was twice as high in the patients with hip fracture than in those without. The effect of hip fracture on mortality between these 2 groups was also the highest in individuals aged between 60 and 69 years.

CONCLUSION

The PD group showed an approximately 2 times higher risk of hip fracture compared with the comparison group, and the post-fracture mortality rate was 2 times higher in the patients with PD with hip fracture than in those without. Those aged 60-69 years were associated with the highest risk of hip fracture and post-hip fracture mortality among patients with PD.

The TOPAZ study: a home-based trial of zoledronic acid to prevent fractures in neurodegenerative parkinsonism

The Trial of Parkinson’s And Zoledronic acid (TOPAZ, https://clinicaltrials.gov/ct2/show/NCT03924414) is a unique collaboration between experts in movement disorders and osteoporosis to test the efficacy of zoledronic acid, an FDA-approved parenteral treatment for osteoporosis, for fracture prevention in people with neurodegenerative parkinsonism. Aiming to enroll 3,500 participants age 65 years or older, TOPAZ is one of the largest randomized, placebo-controlled clinical trials ever attempted in parkinsonism. The feasibility of TOPAZ is enhanced by its design as a U.S.- wide home-based trial without geographical limits. Participants receive information from multiple sources, including specialty practices, support groups and websites. Conducting TOPAZ in participants’ homes takes advantage of online consent technology, the capacity to confirm diagnosis using telemedicine and the availability of research nursing to provide screening and parenteral therapy in homes. Home-based clinical research may provide an efficient, convenient, less expensive method that opens participation in clinical trials to almost anyone with parkinsonism.

A clinical nomogram predicting unplanned intensive care unit admission after hip fracture surgery

BACKGROUND

Despite the improvement of surgical procedures and perioperative management, a portion of patients were still at high risk for intensive care unit admission owing to severe morbidity after hip fracture surgeries. The purpose of this study was to analyze influencing factors and to construct a clinical nomogram to predict unscheduled intensive care unit admission among inpatients after hip fracture surgeries.

METHODS

We enrolled a total of 1,234 hip fracture patients, with 40 unplanned intensive care unit admissions, from January 2011 to December 2018. Demographics, chronic coexisting conditions at admission, laboratory tests, and surgical variables were collected and compared between intensive care unit admission and nonadmission groups using univariate analysis. The optimal lasso model was refined to the whole data set, and multivariate logistic regression was used to assign relative weights. A nomogram incorporating these predictors was constructed to visualize these predictors and their corresponding points of the risk for unplanned intensive care unit admission. The model was validated temporally using an independent data set from January 2019 to December 2019 by receiver operating characteristic area under the curve analysis.

RESULTS

In the development group, we identified age, chronic heart failure, coronary heart disease, chronic obstructive pulmonary disease, Parkinson disease, and serum albumin and creatinine concentration were associated with unscheduled intensive care unit admission using multivariate analysis. The final model had an area under the curve of 0.854 (95% confidence interval, 0.742-0.966). The median calculated odds ratio of intensive care unit admission based on the nomogram was significantly higher for patients in the intensive care unit admission group than in the non-intensive care unit admission group (65.93% vs 0.02%, P < .01). The validation group proved its high predictive power with an area under the curve of 0.96 (95% confidence interval, 0.91-0.99).

CONCLUSION

In this study, we identified several independent factors that may increase the risk for unexpected intensive care unit admission after hip fracture surgery and developed a clinical nomogram based on these variables. Preoperative evaluation using this nomogram might facilitate advanced intensive care unit resource management for high-risk patients whose conditions might easily deteriorate if not closely monitored in general wards after surgeries.

Exercise Therapies for Parkinson's Disease: A Systematic Review and Meta-Analysis

Recently, rehabilitative exercise therapies have been described as an important method of overcoming the limitations of the conventional therapies for Parkinson's disease. The present study aimed to evaluate efficacy and safety of exercise therapies for Parkinson's disease. Randomized controlled trials that evaluated exercise therapies in patients with Parkinson's disease until December 2016 were searched for in five electronic databases: PubMed, CENTRAL, EMBASE, OASIS, and CNKI. Eighteen studies (1,144 patients) were included. The overall methodological quality was not high. Patients who underwent exercise therapies exhibited statistically significant improvements in the total UPDRS, UPDRS II and III, Berg Balance Scale, preferred walking speed, and Timed Up and Go Test compared to patients who underwent nonexercise therapies. In comparison to patients who performed regular activity, patients who underwent exercise therapies exhibited statistically significant improvements in the total UPDRS, UPDRS II, and UPDRS III. Exercise therapies were found to be relatively safe. Exercise therapies might promote improvements in the motor symptoms of Parkinson's disease. However, due to the small number of randomized controlled trials and methodological limitations, we are unable to draw concrete conclusions. Therefore, further studies with better designs will be needed.

Parkinson's disease and osteoporosis: basic and clinical implications

Introduction: Parkinson's disease (PD) is the second most frequent neurodegenerative disease. Lewy bodies, the hallmark of this disease due to an accumulation of α-synuclein, lead to loss of dopamine-regulated motor circuits, concomitantly progressive immobilization and a broad range of nonmotor features. PD patients have more hospitalizations, endure longer recovery time from comorbidities, and exhibit higher mortality than healthy controls. Although often overlooked, secondary osteoporosis has been reported frequently and is associated with a worse prognosis.Areas covered: In this review, we discuss the pathophysiology of PD from a systemic perspective. We searched on PubMed articles from the last 20 years in PD, both clinical features and bone health status. We discuss possible neuro/endocrine mechanisms by which PD impacts the skeleton, review available therapy for osteoporotic fractures and highlight evidence gaps in defining skeletal co-morbid events.Expert opinion: Future research is essential to understand the local and systemic effects of dopaminergic signaling on bone remodeling and to determine how pathological α-synuclein deposition in the central nervous system might impact the skeleton. It is hoped that a systematic approach to the pathogenesis of this disease and its treatment will allow the informed use of osteoporotic drugs to prevent fractures in PD patients.

The risk of hip and non-vertebral fractures in patients with Parkinson's disease and parkinsonism: A systematic review and meta-analysis

Parkinson's disease (PD) is a neurodegenerative disorder that is common in older individuals. PD patients have an increased risk of fractures compared to the general population, perhaps due to multiple falls. However, the fracture risk has not been fully assessed. To assess the impact of PD on the risk of hip and non-vertebral fractures, we conducted a systematic review and meta-analysis. Comprehensive searches of three key bibliographic databases were conducted to identify reviews and primary studies relating to the risk of fractures in patients with PD. Search terms included all relevant terms for Parkinson's disease and for fractures. We selected observational studies with data on the risk of fractures in adults with PD compared to controls without the diagnosis. Study quality was assessed using the Newcastle Ottawa Scale. The random-effects model was used to pool the results. Eighteen studies were included in the review. Seventeen independent studies (14 cohort and 3 case-control studies) were included in the hip fracture analysis. Nine studies (all cohorts, no case-control studies) were included in the non-vertebral fracture analysis. Study quality was judged to be moderate to good. Overall, PD patients had an increased risk for both hip fractures (2.40, 95% CI 2.04 to 2.82) and non-vertebral fractures (1.80, 95% CI 1.60 to 2.01) compared to controls. The relative risk for hip fractures was higher in men (2.93, 95% CI 2.05 to 4.18) than in women (1.81, 95% CI 1.61 to 2.04). There were no effects of the study design, geographical region, or criteria for diagnosing Parkinson's disease on these estimates of fracture risk. There is an increase in the risk of hip and non-vertebral fractures in patients with Parkinson's disease and we recommend a re-evaluation of the clinical guidelines on bone health in patients with PD to address this.

Using Medical Claims Analyses to Understand Interventions for Parkinson Patients

The scientific evidence to support the value of a range of non-pharmacological interventions for people with Parkinson’s disease (PD) is increasing. However, showing unequivocally that specific interventions are better than usual care is not straightforward because of generic drawbacks of clinical trials. Here, we address these challenges, specifically related to the context of evaluating complex non-pharmacological interventions for people with PD. Moreover, we discuss the potential merits of undertaking “real world” analyses using medical claims data. We illustrate this approach by discussing an interesting recent publication in The Lancet Neurology, which used such an approach to demonstrate the value of specialized physiotherapy for PD patients, over and above usual care physiotherapy.

Postural Instability in Parkinson's Disease: A Review

Parkinson’s disease (PD) is a heterogeneous progressive neurodegenerative disorder, which typically affects older adults; it is predicted that by 2030 about 3% of the world population above 65 years of age is likely to be affected. At present, the diagnosis of PD is clinical, subjective, nonspecific, and often inadequate. There is a need to quantify the PD factors for an objective disease assessment. Among the various factors, postural instability (PI) is unresponsive to the existing treatment strategies resulting in morbidity. In this work, we review the physiology and pathophysiology of postural balance that is essential to treat PI among PD patients. Specifically, we discuss some of the reported factors for an early PI diagnosis, including age, nervous system lesions, genetic mutations, abnormal proprioception, impaired reflexes, and altered biomechanics. Though the contributing factors to PI have been identified, how their quantification to grade PI severity in a patient can help in treatment is not fully understood. By contextualizing the contributing factors, we aim to assist the future research efforts that underpin posturographical and histopathological studies to measure PI in PD. Once the pathology of PI is established, effective diagnostic tools and treatment strategies could be developed to curtail patient falls.

Effect of Parkinson's Disease on Hemiarthroplasty Outcomes After Femoral Neck Fractures

BACKGROUND

The purpose of this study was to evaluate the outcomes following hemiarthroplasty (HA) for femoral neck fractures (FNFs) in patients with Parkinson's disease (PD) compared with patients without PD.

METHODS

This was a retrospective review utilizing the Nationwide Readmissions Database, a national database incorporating inpatient hospitalization information. Using the Nationwide Readmissions Database, patients who underwent HA for FNF between 2010-2014 were identified. International Classification of Diseases, 9th Revision, codes were used to find a subset of patients with PD. Primary outcomes of interest included death, hospital readmission, periprosthetic fracture, postoperative dislocation, any revision surgery, and revision surgery for instability, fracture, or infection.

RESULTS

There were a total of 7721 (4%) patients with PD. There was no difference in the risk of death or any postoperative complications during index hospitalization for these patients. However, PD patients had an increased risk of hospital readmission (odds ratio [OR] = 1.13, 95% confidence interval [CI]: 1.02-1.26) and postoperative dislocation (OR = 2.10, 95% CI: 1.58-2.80) within 90 days of surgery. PD patients also had an increased risk of revision surgery for instability (OR = 2.20, 95% CI: 1.48-3.28), despite no difference in the risk of any revision surgery, revision surgery for fracture, or revision surgery for infection.

CONCLUSION

In this retrospective cohort study, PD patients who underwent a HA for FNF had a greater risk of postoperative dislocation and revision surgery for instability within 90 days. These findings are not only important to consider when managing these at-risk patients but also stress the need to allocate operative and postoperative resources to prevent and treat instability.

LEVEL OF EVIDENCE

3 (Retrospective cohort study).

Dementia predicted one-year mortality for patients with first hip fracture: a population-based study

Aims

We aimed to determine the effect of dementia and Parkinson's disease on one, three and 12-month mortality following surgery for fracture of the hip in elderly patients from an Asian population.

Patients and Methods

Using a random sample of patients taken from the Taiwan National Health Insurance Research Database, this retrospective cohort study analyzed the data on 6626 elderly patients who sustained a fracture of the hip between 1997 and 2012 who had ICD-9 codes within the general range of hip fracture (820.xx). We used Cox regression to estimate the risk of death associated with dementia, Parkinson's disease or both, adjusting for demographic, clinical, treatment, and provider factors.

Results

Among 6626 hip fracture patients, 10.20% had dementia alone, 5.60% had Parkinson's disease alone, and 2.67% had both. Corresponding one-year mortality rates were 15.53%, 11.59%, and 15.82%, compared with 9.22% for those without neurological illness. Adjusted hazard ratio for one-year mortality was 1.45 (95% confidence intervals (CI) 1.17 to 1.79) for those with dementia, and 1.57 (95% CI 1.07 to 2.30) with both dementia and Parkinson's disease versus patients with neither. There was no significant association with death for Parkinson's disease alone. Age, male gender and comorbidities were also associated with a higher risk of mortality.

Conclusion

Dementia, with or without Parkinson's disease, is an independent predictor of mortality following surgery for fractures of the hip. Age, male gender and comorbidities also increase the risk of death. Parkinson's disease alone has no significant effect. Cite this article: Bone Joint J 2018;100-B:1220-6.

[Perioperative treatment progress of Parkinson's disease with hip fracture]

Objective

To review the progress of perioperative treatments for patients of Parkinson's disease and hip fractures.

Methods

The related literature of treatments for patients of Parkinson's disease and hip fractures were reviewed and analyzed from the aspects such as the perioperative management, selection of operation ways, and prognosis.

Results

The patients of Parkinson's disease are more likely to sustain hip fractures because of postural instability and osteoporosis. The perioperative treatments for patients of Parkinson's disease and hip fractures should be determined by orthopedists, neurologist, anesthesiologist, and physical therapist. There is still controversy about the selection of operation and surgical approach. And the prognosis of patients of Parkinson's disease and hip fractures are associated with the severity of Parkinson's disease.

Conclusion

There are few clinical studies about the patients of Parkinson's disease and hip fractures. The mid-term and long-term functional outcomes of patients of Parkinson's disease and hip fractures are unsufficient. And the best treatments of patients of Parkinson's disease and hip fractures need to be further explored.

Effectiveness and costs of specialised physiotherapy given via ParkinsonNet: a retrospective analysis of medical claims data

BACKGROUND

Parkinson's disease is a complex condition that is best managed by specialised professionals. Trials show that specialised allied health interventions are cost-effective, as compared with usual care. We aimed to study the long-term benefits of specialised physiotherapy using the ParkinsonNet approach in real-world practice.

METHODS

We did an observational study, retrospectively analysing a database of health insurance claims that included a representative population of Dutch patients with Parkinson's disease, who were followed for up to 3 years (Jan 1, 2013, to Dec 31, 2015). Eligibility criteria included having both a diagnosis of Parkinson's disease and having received physiotherapy for the disease. Allocation to specialised or usual care physiotherapy was based on the choices of patients and referring physicians. We used a mixed-effects model to compare health-care use and outcomes between patients treated by specialised or usual care physiotherapists. The primary outcome was the percentage of patients with a Parkinson's disease-related complication (ie, visit or admission to hospital because of fracture, other orthopaedic injuries, or pneumonia) adjusted for baseline variables. We compared physiotherapist caseload, the number of physiotherapy sessions, physiotherapy costs, and total health-care costs (including hospital care, but excluding community care, long-term care, and informal care) between the groups, and used a Cox's proportional hazard model for survival time to establish whether mortality was influenced by treatment by a specialised physiotherapist.

FINDINGS

We analysed 2129 patients (4649 observations) receiving specialised physiotherapy and 2252 patients (5353 observations) receiving usual care physiotherapy. Significantly fewer patients treated by a specialised physiotherapist had a Parkinson's disease-related complication (n=368 [17%]) than patients treated by a usual care physiotherapist (n=480 [21%]; odds ratio 0·67, 95% CI 0·56-0·81, p<0·0001). The annual caseload of patients per therapist was significantly higher for specialised physiotherapists (mean 3·89 patients per therapist [SD 3·91]) than usual care physiotherapists (1·48 [1·24]). Patients who saw specialised physiotherapists received fewer treatment sessions (mean 33·72 [SD 26·70]) than usual care physiotherapists (47·97 [32·11]). Consequently, expenditure was lower for specialised than usual care physiotherapists, both for direct costs (mean €933 [SD 843] vs €1329 [1021]; annual difference €395, 95% CI 358-432, p<0·0001) and total health-care expenditure (€2056 [3272] vs €2586 [3756]; €530, 391-669, p<0·0001). Mortality risk was lower for patients receiving specialised physiotherapy (134 [6%]) compared with patients receiving usual care physiotherapy (205 [9%], p=0·001) before correction for baseline variables, although Cox's survival model showed no significant difference between the two (hazard ratio 0·86, 95% CI 0·69-1·07, p=0·195).

INTERPRETATION

These results confirm the findings from controlled trials, and offer evidence that specialised physiotherapy as delivered through ParkinsonNet is associated with fewer Parkinson's disease-related complications and lower costs in real-world practice. Neurologists can facilitate specialised physiotherapy by specific referral to such experts.

FUNDING

None.

Hip fractures and Parkinson's disease: A case series

There are no specific guidelines for treating Parkinson's disease patients who present with a hip fracture. Here we present a large cohort of patients with Parkinson's disease who suffered hip fractures. Our aim was to assess for differences between a Parkinson's disease population and a non-Parkinson's disease population with hip fractures and make recommendations on management guidelines. We performed a comprehensive analysis of prospectively collected data on all patients with hip fracture who were admitted into our department over a period of 29 years. In total 9225 patients with hip fractures were included in this study, 452 (4.9%) patients had Parkinson's disease. The mobility scores were worse pre- and post-operatively in the Parkinson's group as were mini-mental scores and ASA grade. Post-operative complications were similar between the two groups, with no difference in dislocation rate or wound complications. However, other outcomes including mobility and mortality rate at 1year were worse in the Parkinson's group. These patients also had a longer hospital stay and were more likely to be immobile and discharged to an institution. We recommend that Parkinson's disease patients should be assessed more thoroughly in the peri-operative period and arrangement for rehab and discharge planning should commence as soon as possible following admission. The consent process should reflect longer hospital stays, worse mobility, higher mortality and increased likelihood of discharge to institution but concern over increased complications, specifically dislocation was not evident in our data.

Risk and Prevention of Fracture in Patients With Major Medical Illnesses: A Mini-Review

Patients with several medical conditions, including Parkinson's disease, recent stroke, HIV, and heart failure, have a high risk of hip fracture. These patients will also have more severe consequences of a hip fracture, including a greater chance of dying and more prolonged disability. Together, there are nearly as many patients with medical conditions that substantially increase the risk of hip fracture as there are people with osteoporosis by femoral neck bone mineral density (BMD). The contributions of falling and decreased bone mass to the increased risks with these conditions are not certain. Although there are few data about whether and what type of treatments these patients receive to prevent fracture, it is likely that few receive pharmacologic treatments that have been shown to reduce the risk of hip fracture. There is a need to show that drug treatments that strengthen bone also reduce fracture risk in patients whose risk may be owing in greater part to traumatic falls than osteoporosis. Assuming that treatments are efficacious in these patients, there is a major opportunity to substantially reduce the incidence and consequences of hip fracture by reaching more of them with drug treatments to reduce the risk of hip fracture. This will require engagement of specialists who have little expertise and perhaps limited interest in preventing fractures, or new approaches to delivering drug treatments to prevent fracture directly to the patients at risk. © 2016 American Society for Bone and Mineral Research.

Comorbid Parkinson's disease, falls and fractures in the 2010 National Emergency Department Sample

INTRODUCTION

Parkinson's disease (PD) is a progressive, neurodegenerative disorder of multifactorial etiology affecting ∼1% of older adults. Research focused on linking PD to falls and bone fractures has been limited in Emergency Department (ED) settings, where most injuries are identified. We assessed whether injured U.S. ED admissions with PD diagnoses were more likely to exhibit comorbid fall- or non-fall related bone fractures and whether a PD diagnosis with a concomitant fall or bone fracture is linked to worse prognosis.

METHODS

We performed secondary analyses of 2010 Healthcare Utilization Project National ED Sample from 4,253,987 admissions to U.S. EDs linked to injured elderly patients. ED discharges with ICD-9-CM code (332.0) were identified as PD and those with ICD-9-CM code (800.0-829.0) were used to define bone fracture location. Linear and logistic regression models were constructed to estimate slopes (B) and odds ratios (OR) with 95% confidence intervals (CI).

RESULTS

PD admissions had 28% increased adjusted prevalence of bone fracture. Non-fall injuries showed stronger relationship between PD and bone fracture (OR_adj = 1.33, 95% CI: 1.22-1.45) than fall injuries (OR_adj = 1.06, 95% CI: 1.01-1.10). PD had the strongest impact on hospitalization length when bone fracture and fall co-occurred, and total charges were directly associated with PD only for fall injuries. Finally, PD status was not related to in-hospital death in this population.

CONCLUSION

Among injured U.S. ED elderly patient visits, those with PD had higher bone fracture prevalence and more resource utilization especially among fall-related injuries. No association of PD with in-hospital death was noted.

Risk Factors for Hip Fracture in Older Men: The Osteoporotic Fractures in Men Study (MrOS)

Almost 30% of hip fractures occur in men; the mortality, morbidity, and loss of independence after hip fractures are greater in men than in women. To comprehensively evaluate risk factors for hip fracture in older men, we performed a prospective study of 5994 men, primarily white, age 65+ years recruited at six US clinical centers. During a mean of 8.6 years of 97% complete follow-up, 178 men experienced incident hip fractures. Information on risk factors including femoral neck bone mineral density (FNBMD) was obtained at the baseline visit. Cox proportional hazards models were used to calculate the hazard ratio (HR) with 95% confidence intervals; Fine and Gray models adjusted for competing mortality risk. Older age (≥75 years), low FNBMD, currently smoking, greater height and height loss since age 25 years, history of fracture, use of tricyclic antidepressants, history of myocardial infarction or angina, hyperthyroidism or Parkinson's disease, lower protein intake, and lower executive function were all associated with an increased hip fracture risk. Further adjustment for competing mortality attenuated HR for smoking, hyperthyroidism, and Parkinson's disease. The incidence rate of hip fracture per 1000 person-years (PY) was greatest in men with FNBMD T-scores <-2.5 (white women reference database) who also had 4+ risk factors, 33.4. Men age ≥80 years with 3+ major comorbidities experienced hip fracture at rates of 14.52 versus 0.88 per 1000 PY in men age <70 years with zero comorbidities. Older men with low FNBMD, multiple risk factors, and multimorbidity have a high risk of hip fracture. Many of these assessments can easily be incorporated into routine clinical practice and may lead to improved risk stratification. © 2016 American Society for Bone and Mineral Research.

Associations between Anticholinergic Burden and Adverse Health Outcomes in Parkinson Disease

Background

Elderly adults should avoid medications with anticholinergic effects since they may increase the risk of adverse events, including falls, delirium, and cognitive impairment. However, data on anticholinergic burden are limited in subpopulations, such as individuals with Parkinson disease (PD). The objective of this study was to determine whether anticholinergic burden was associated with adverse outcomes in a PD inpatient population.

Methods

Using the Cerner Health Facts® database, we retrospectively examined anticholinergic medication use, diagnoses, and hospital revisits within a cohort of 16,302 PD inpatients admitted to a Cerner hospital between 2000 and 2011. Anticholinergic burden was computed using the Anticholinergic Risk Scale (ARS). Primary outcomes were associations between ARS score and diagnosis of fracture and delirium. Secondary outcomes included associations between ARS score and 30-day hospital revisits.

Results

Many individuals (57.8%) were prescribed non-PD medications with moderate to very strong anticholinergic potential. Individuals with the greatest ARS score (≥4) were more likely to be diagnosed with fractures (adjusted odds ratio (AOR): 1.56, 95% CI: 1.29–1.88) and delirium (AOR: 1.61, 95% CI: 1.08–2.40) relative to those with no anticholinergic burden. Similarly, inpatients with the greatest ARS score were more likely to visit the emergency department (adjusted hazard ratio (AHR): 1.32, 95% CI: 1.10–1.58) and be readmitted (AHR: 1.16, 95% CI: 1.01–1.33) within 30-days of discharge.

Conclusions

We found a positive association between increased anticholinergic burden and adverse outcomes among individuals with PD. Additional pharmacovigilance studies are needed to better understand risks associated with anticholinergic medication use in PD.

Mortality and Revision Surgery Are Increased in Patients With Parkinson's Disease and Fractures of the Femoral Neck

BACKGROUND

Patients with Parkinson's disease are at increased risk for falls and associated hip fractures as a result of tremor, bradykinesia, rigidity, and postural instability. The available literature is limited and conflicting regarding the optimal surgical treatment and risk for postoperative complications and mortality in this unique patient population.

QUESTIONS/PURPOSES

We asked: (1) Is there a difference in mortality after surgical treatment of hip fractures in patients with Parkinson's disease compared with similar patients with hip fractures without Parkinson's disease? (2) Does Parkinson's disease lead to a higher rate of reoperation after operative treatment of femoral neck fractures? (3) Does Parkinson's disease lead to a higher rate of dislocation after hemiarthroplasty for displaced femoral neck fractures, and (4) does the operative approach affect dislocation rates?

METHODS

In this case-controlled study, we retrospectively reviewed 141 patients with a diagnosis of Parkinson's disease and a fracture of the femoral neck. Each patient with Parkinson's disease was matched with two control patients (n = 282) without Parkinson's disease stratified by age, sex, American Society of Anesthesiologists classification, and fracture type (nondisplaced/displaced). Clinical outcomes included mortality after surgical intervention, rate of reoperation, dislocation events after hemiarthroplasty, and the rate of failure after internal fixation for nondisplaced fractures.

RESULTS

The median survival time of the patients with Parkinson's disease after fracture was 31 months (95% CI, 25-37 months) compared with 45 months (95% CI, 39-50 months) in our control group (p = 0.007). The rate of reoperation for displaced and nondisplaced fractures was higher in the Parkinson's disease group compared with the control group (11% versus 4%; p = 0.005). Failure of fixation for patients treated with internal fixation of nondisplaced femoral neck fractures was significantly higher in the Parkinson's disease group compared with our control group (22% versus 5%; p = 0.01). Dislocation rates after hemiarthroplasty were significantly higher in the Parkinson's disease group compared with the control group (8% versus 1%; p = 0.003). Patients treated with a hemiarthroplasty through an anterolateral approach had a significantly lower dislocation rate compared with those treated with a posterior approach (2% versus 15%; p = 0.002).

CONCLUSIONS

Parkinson's disease is an independent predictor of mortality after femoral neck fracture and is associated with an increased rate of dislocation, revision surgery, and failure of internal fixation. Although patients with Parkinson's disease with a nondisplaced or valgus impacted femoral neck fracture may be treated with internal fixation, they are at significantly higher risk of failure of fixation compared with patients without Parkinson's disease. Use of a hemiarthroplasty through an anterolateral approach may reduce the likelihood of requiring a revision operation.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Occurrence, management and outcomes of hip fractures in patients with Parkinson's disease

INTRODUCTION

Hip fractures can be debilitating, especially in patients with pre-existing Parkinson's disease; they have reportedly worse outcomes than non-Parkinson's disease patients.

SOURCES OF DATA

A computerized literature search on PubMed, Medline, Embase, and CINAHL, supplemented by a manual search of related publications.

AREAS OF AGREEMENT

Parkinson's disease patients were found to have significantly lower bone mineral density; higher incidence of falls and hip fractures; delays to receiving their Parkinson's disease medication and surgery; higher risk of pneumonia, urinary infection, pressure sores, post-operative mortality; surgical complications and sequelae, including failed fixation, dislocation, longer hospital stay, re-operation; and increased risk of contralateral hip fracture.

AREAS OF CONTROVERSY

Regain of mobility and return to previous residential status have been variably reported.

GROWING POINTS

All Parkinson's disease patients should be screened and considered for primary prevention treatment. On admission with hip fractures, attention should be paid to avoid delays to medication, ensuring safe anaesthetic and timely surgery, and post-operative chest physiotherapy and mobilization.

RESEARCH

Research is needed in minimizing the bone-resorptive effects of anti-Parkinson's disease medication.

Operative versus nonoperative treatment of geriatric ankle fractures: a Medicare Part A claims database analysis

BACKGROUND

The incidence of ankle fractures is increasing in the geriatric population, and several studies suggest them to be the third most common extremity fracture in this age group. Previous work has reflected relatively low complication rates during operative treatment. Little is known, however, about the association between these injuries and overall mortality, nor whether operative intervention has any effect on mortality. We hypothesized that geriatric ankle fractures would be correlated with an elevated mortality rate and that operative intervention would be associated with a reduced mortality when compared to nonoperative management.

METHODS

Following Institutional Review Board approval we retrospectively assessed all relevant 2008 part A inpatient claims from the Medicare database. We queried diagnosis codes for ankle fractures, and then excluded any patients whose age was less then 65 or had an admission related to an ankle fracture during the previous year. Operative patients were then identified by their ICD-9 procedure codes occurring within 30 days of their initial diagnosis code; all other patients were presumed to be treated without operative intervention, thereby creating 2 groups for comparison. We then analyzed this database for specific variables including overall mortality, length of stay, age distribution, and other demographical characteristics. Groups were compared with Elixhauser and Deyo-Charlson scores to determine the level of comorbidities in each group. Multivariate logistic regression analysis was used to determine if operative intervention had a protective effect.

RESULTS

In all, 19 648 patients with an ankle fracture were identified. Of those, 15 193 underwent operative intervention (77.3% ) and 4455 were treated nonoperatively (22.7% ). The mean ages for nonoperative and operative intervention were 80.9 and 76.5, respectively (P < .0001). The average length of stay for nonoperative management was 4.5 days, while operative intervention resulted in a length of stay of 4.6 days (P = .43). One-year mortality was 21.5% for the nonoperative group and 9.1% for the operative group (P < .0001). The mean Elixhauser score for the nonoperative group was 2.5 and 2.2 for the operative group (P < .0001). The mean Deyo-Charlson score was 1.3 and 1.0 for the nonoperative and operative groups, respectively (P < .0001). Multivariate logistic regression analysis demonstrated an odds ratio of 0.534 of death within 1 year for patients undergoing operative intervention as compared to nonoperative intervention (95% CI 0.483-0.591, P < .0001).

CONCLUSION

The incidence of geriatric ankle fractures continue to increase as our population continues to grow older. A significantly larger number of those patients were treated with operative intervention, at a ratio of approximately 3:1 versus nonoperative management. Despite a relatively low overall reported complication rate with treatment of these injuries, they are associated with substantially increased 1-year mortality in both patient groups. Compared to the operative group, the nonoperative cohort demonstrated a 2-fold elevated mortality rate, although this may be related to them being an arguably more frail population as suggested by both comorbidity indexes. In spite of the difference in comorbidities, logistic regression analysis demonstrated operative intervention to have a protective effect.

LEVEL OF EVIDENCE

Level III, comparative series.

Risk and adverse outcomes of fractures in patients with Parkinson's disease: two nationwide studies

The association between Parkinson's disease and fracture was not completely understood. This nationwide study investigated increased risk of fracture in patients with Parkinson's disease. In the nested cohort study, Parkinson's disease was associated with pneumonia, septicemia, stroke, urinary tract infection, and mortality after fracture admission.

INTRODUCTION

Falls are a common complication in people with Parkinson's disease (PD). This study evaluated fracture risk and post-fracture outcomes in patients with PD.

METHODS

We identified 1,423 adults aged 40 years and older newly diagnosed with PD using the Taiwan National Health Insurance Research Database from 2000 to 2003. Comparison cohort consisted of 5,692 adults without PD randomly selected from the same dataset, frequency matched in age and sex. Followed-up events of fracture from January 1, 2000, until December 31, 2008, were ascertained from medical claims. Adjusted hazard ratios (HR) and 95 % confidence interval (CI) of fracture associated with PD were evaluated. Another nested cohort study of 397,766 hospitalized fracture patients analyzed for adjusted odds ratios (ORs) and 95 % CIs of adverse events after fracture among patients with and without PD between 2004 and 2010.

RESULTS

The incidences of fracture for people with and without PD were 39.5 and 23.9 per 1,000 person-years, respectively (p < 0.0001). Compared with control, the adjusted HR of fracture was 2.25 (95 % CI 1.97-2.58) for PD patients. Previous PD was associated with risks of pneumonia (OR 1.44, 95 % CI 1.36-1.52), septicemia (OR 1.41, 95 % CI 1.33-1.49), stroke (OR 1.40, 95 % CI 1.32-1.50), urinary tract infection (OR 1.53, 95 % CI 1.46-1.61), and mortality (OR 1.25, 95 % CI 1.15-1.35) after fracture.

CONCLUSIONS

PD was associated with higher risk of fracture. Patients with PD had more complications and mortality after fracture. Fracture prevention and attention to post-fracture adverse events are needed for this susceptible population.

Groundwater Pesticide Levels and the Association With Parkinson Disease

It is unclear whether exposure to environmentally relevant levels of pesticides in groundwater is associated with an increased risk of Parkinson disease (PD). The purpose of this study was to examine the relationship between PD and pesticide levels in groundwater. This cross-sectional study included 332 971 Medicare beneficiaries, including 4207 prevalent cases of PD from the 2007 Colorado Medicare Beneficiary Database. Residential pesticide levels were estimated from a spatial model based on 286 well water samples with atrazine, simazine, alachlor, and metolachlor measurements. A logistic regression model with known PD risk factors was used to assess the association between residential groundwater pesticide levels and prevalent PD. We found that for every 1.0 µg/L of pesticide in groundwater, the risk of PD increases by 3% (odds ratio = 1.03; 95% confidence interval: 1.02-1.04) while adjusting for age, race/ethnicity, and gender suggesting that higher age-standardized PD prevalence ratios are associated with increasing levels of pesticides in groundwater.