Suicidal ideation among people with Parkinson's disease and comparison with a control group.

BACKGROUND: Detection of suicidal ideation (SI) is key for trying to prevent suicide. The aim of this study was to analyze the frequency of SI and related factors in Spanish people with Parkinson's Disease (PwPD) and to compare them with a control group. METHODS: PD patients and controls recruited from the Spanish cohort COPPADIS from January 2016 to November 2017 were included. Two visits were conducted: V0 (baseline); V2 (2-year ± 1 month follow-up). SI was defined as a score ≥1 on item nine of the Beck Depression Inventory-II (BDI-II). Regression analyses were conducted to identify factors related to SI. RESULTS: At baseline, 693 PwPD (60.2% males; 62.59 ± 8.91 years old) and 207 controls (49.8% males; 60.99 ± 8.32 years old) were included. No differences between PwPD and controls were detected in SI frequency at either V0 (5.1% [35/693] vs. 4.3% [9/207]; p = 0.421) or at V2 (5.1% [26/508] vs. 4.8% [6/125]; p = 0.549). Major depression (MD) and a worse quality of life were associated with SI at both visits in PwPD: V0 (MD, OR = 5.63; p = 0.003; PDQ-39, OR = 1.06; p = 0.021); V2 (MD, OR = 4.75; p = 0.027; EUROHIS-QOL8, OR = 0.22; p = 0.006). A greater increase in the BDI-II total score from V0 to V2 was the only factor predicting SI at V2 (OR = 1.21; p = 0.002) along with an increase in the total number of non-antiparkinsonian drugs (OR = 1.39; p = 0.041). CONCLUSION: The frequency of SI (5%) in PwPD was similar to in controls. Depression, a worse quality of life, and a greater comorbidity were related to SI.

Prevalence and Factors Associated with Drooling in Parkinson's Disease: Results from a Longitudinal Prospective Cohort and Comparison with a Control Group.

Introduction: Drooling in Parkinson's disease (PD) is frequent but often goes underrecognized. Our aim was to examine the prevalence of drooling in a PD cohort and compare it with a control group. Specifically, we identified factors associated with drooling and conducted subanalyses in a subgroup of very early PD patients. Patients and Methods. PD patients who were recruited from January 2016 to November 2017 (baseline visit; V0) and evaluated again at a 2-year ± 30-day follow-up (V2) from 35 centers in Spain from the COPPADIS cohort were included in this longitudinal prospective study. Subjects were classified as with or without drooling according to item 19 of the NMSS (Nonmotor Symptoms Scale) at V0, V1 (1-year ± 15 days), and V2 for patients and at V0 and V2 for controls. Results: The frequency of drooling in PD patients was 40.1% (277/691) at V0 (2.4% (5/201) in controls; p < 0.0001), 43.7% (264/604) at V1, and 48.2% (242/502) at V2 (3.2% (4/124) in controls; p < 0.0001), with a period prevalence of 63.6% (306/481). Being older (OR = 1.032; p = 0.012), being male (OR = 2.333; p < 0.0001), having greater nonmotor symptom (NMS) burden at the baseline (NMSS total score at V0; OR = 1.020; p < 0.0001), and having a greater increase in the NMS burden from V0 to V2 (change in the NMSS total score from V0 to V2; OR = 1.012; p < 0.0001) were identified as independent predictors of drooling after the 2-year follow-up. Similar results were observed in the group of patients with ≤2 years since symptom onset, with a cumulative prevalence of 64.6% and a higher score on the UPDRS-III at V0 (OR = 1.121; p = 0.007) as a predictor of drooling at V2. Conclusion: Drooling is frequent in PD patients even at the initial onset of the disease and is associated with a greater motor severity and NMS burden.

Staging Parkinson's Disease According to the MNCD (Motor/Non-motor/Cognition/Dependency) Classification Correlates with Disease Severity and Quality of Life.

BACKGROUND: Recently, a novel simple classification called MNCD, based on 4 axes (Motor; Non-motor; Cognition; Dependency) and 5 stages, has been proposed to classify Parkinson's disease (PD). OBJECTIVE: Our aim was to apply the MNCD classification in a cohort of PD patients for the first time and also to analyze the correlation with quality of life (QoL) and disease severity. METHODS: Data from the baseline visit of PD patients recruited from 35 centers in Spain from the COPPADIS cohort fromJanuary 2016 to November 2017 were used to apply the MNCD classification. Three instruments were used to assess QoL:1) the 39-item Parkinson's disease Questionnaire [PDQ-39]); PQ-10; the EUROHIS-QOL 8-item index (EUROHIS-QOL8). RESULTS: Four hundred and thirty-nine PD patients (62.05±7.84 years old; 59% males) were included. MNCD stage was:stage 1, 8.4% (N = 37); stage 2, 62% (N = 272); stage 3, 28.2% (N = 124); stage 4-5, 1.4% (N = 6). A more advancedMNCD stage was associated with a higher score on the PDQ39SI (p < 0.0001) and a lower score on the PQ-10 (p< 0.0001) and EUROHIS-QOL8 (p< 0.0001). In many other aspects of the disease, such as disease duration, levodopa equivalent daily dose, motor symptoms, non-motor symptoms, and autonomy for activities of daily living, an association between the stage and severity was observed, with data indicating a progressive worsening related to disease progression throughout the proposed stages. CONCLUSION: Staging PD according to the MNCD classification correlated with QoL and disease severity. The MNCD could be a proper tool to monitor the progression of PD.

Sex Differences in Motor and Non-Motor Symptoms among Spanish Patients with Parkinson's Disease.

BACKGROUND AND OBJECTIVE: Sex plays a role in Parkinson's disease (PD) mechanisms. We analyzed sex difference manifestations among Spanish patients with PD. PATIENTS AND METHODS: PD patients who were recruited from the Spanish cohort COPPADIS from January 2016 to November 2017 were included. A cross-sectional and a two-year follow-up analysis were conducted. Univariate analyses and general linear model repeated measure were used. RESULTS: At baseline, data from 681 PD patients (mean age 62.54 ± 8.93) fit the criteria for analysis. Of them, 410 (60.2%) were males and 271 (39.8%) females. There were no differences between the groups in mean age (62.36 ± 8.73 vs. 62.8 ± 9.24; p = 0.297) or in the time from symptoms onset (5.66 ± 4.65 vs. 5.21 ± 4.11; p = 0.259). Symptoms such as depression (p < 0.0001), fatigue (p < 0.0001), and pain (p < 0.00001) were more frequent and/or severe in females, whereas other symptoms such as hypomimia (p < 0.0001), speech problems (p < 0.0001), rigidity (p < 0.0001), and hypersexuality (p < 0.0001) were more noted in males. Women received a lower levodopa equivalent daily dose (p = 0.002). Perception of quality of life was generally worse in females (PDQ-39, p = 0.002; EUROHIS-QOL8, p = 0.009). After the two-year follow-up, the NMS burden (Non-Motor Symptoms Scale total score) increased more significantly in males (p = 0.012) but the functional capacity (Schwab and England Activities of Daily Living Scale) was more impaired in females (p = 0.001). CONCLUSION: The present study demonstrates that there are important sex differences in PD. Long-term prospective comparative studies are needed.

Risk of Cognitive Impairment in Patients With Parkinson's Disease With Visual Hallucinations and Subjective Cognitive Complaints.

BACKGROUND AND PURPOSE: Visual hallucinations (VH) and subjective cognitive complaints (SCC) are associated with cognitive impairment (CI) in Parkinson's disease. Our aims were to determine the association between VH and SCC and the risk of CI development in a cohort of patients with Parkinson's disease and normal cognition (PD-NC). METHODS: Patients with PD-NC (total score of >80 on the Parkinson's Disease Cognitive Rating Scale [PD-CRS]) recruited from the Spanish COPPADIS cohort from January 2016 to November 2017 were followed up after 2 years. Subjects with a score of ≥1 on domain 5 and item 13 of the Non-Motor Symptoms Scale at baseline (V0) were considered as "with SCC" and "with VH," respectively. CI at the 2-year follow-up (plus or minus 1 month) (V2) was defined as a PD-CRS total score of <81. RESULTS: At V0 (n=376, 58.2% males, age 61.14±8.73 years [mean±SD]), the frequencies of VH and SCC were 13.6% and 62.2%, respectively. VH were more frequent in patients with SCC than in those without: 18.8% (44/234) vs 4.9% (7/142), p<0.0001. At V2, 15.2% (57/376) of the patients had developed CI. VH presenting at V0 was associated with a higher risk of CI at V2 (odds ratio [OR]=2.68, 95% confidence interval=1.05-6.83, p=0.0.039) after controlling for the effects of age, disease duration, education, medication, motor and nonmotor status, mood, and PD-CRS total score at V0. Although SCC were not associated with CI at V2, presenting both VH and SCC at V0 increased the probability of having CI at V2 (OR=3.71, 95% confidence interval=1.36-10.17, p=0.011). CONCLUSIONS: VH were associated with the development of SCC and CI at the 2-year follow-up in patients with PD-NC.

Falls Predict Acute Hospitalization in Parkinson's Disease.

BACKGROUND: There is a need for identifying risk factors for hospitalization in Parkinson's disease (PD) and also interventions to reduce acute hospital admission. OBJECTIVE: To analyze the frequency, causes, and predictors of acute hospitalization (AH) in PD patients from a Spanish cohort. METHODS: PD patients recruited from 35 centers of Spain from the COPPADIS-2015 (COhort of Patients with PArkinson's DIsease in Spain, 2015) cohort from January 2016 to November 2017, were included in the study. In order to identify predictors of AH, Kaplan-Meier estimates of factors considered as potential predictors were obtained and Cox regression performed on time to hospital encounter 1-year after the baseline visit. RESULTS: Thirty-five out of 605 (5.8%) PD patients (62.5±8.9 years old; 59.8% males) presented an AH during the 1-year follow-up after the baseline visit. Traumatic falls represented the most frequent cause of admission, being 23.7% of all acute hospitalizations. To suffer from motor fluctuations (HR [hazard ratio] 2.461; 95% CI, 1.065-5.678; p = 0.035), a very severe non-motor symptoms burden (HR [hazard ratio] 2.828; 95% CI, 1.319-6.063; p = 0.008), falls (HR 3.966; 95% CI 1.757-8.470; p = 0.001), and dysphagia (HR 2.356; 95% CI 1.124-4.941; p = 0.023) was associated with AH after adjustment to age, gender, disease duration, levodopa equivalent daily dose, total number of non-antiparkinsonian drugs, and UPDRS-IIIOFF. Of the previous variables, only falls (HR 2.998; 95% CI 1.080-8.322; p = 0.035) was an independent predictor of AH. CONCLUSION: Falls is an independent predictor of AH in PD patients.

Motor Fluctuations Development Is Associated with Non-Motor Symptoms Burden Progression in Parkinson's Disease Patients: A 2-Year Follow-Up Study.

Objective: The aim of the present study was to analyze the progression of non-motor symptoms (NMS) burden in Parkinson's disease (PD) patients regarding the development of motor fluctuations (MF). Methods: PD patients without MF at baseline, who were recruited from January 2016 to November 2017 (V0) and evaluated again at a 2-year follow-up (V2) from 35 centers of Spain from the COPPADIS cohort, were included in this analysis. MF development at V2 was defined as a score ≥ 1 in the item-39 of the UPDRS-Part IV, whereas NMS burden was defined according to the Non-motor Symptoms Scale (NMSS) total score. Results: Three hundred and thirty PD patients (62.67 ± 8.7 years old; 58.8% males) were included. From V0 to V2, 27.6% of the patients developed MF. The mean NMSS total score at baseline was higher in those patients who developed MF after the 2-year follow-up (46.34 ± 36.48 vs. 34.3 ± 29.07; p = 0.001). A greater increase in the NMSS total score from V0 to V2 was observed in patients who developed MF (+16.07 ± 37.37) compared to those who did not develop MF (+6.2 ± 25.8) (p = 0.021). Development of MF after a 2-year follow-up was associated with an increase in the NMSS total score (ß = 0.128; p = 0.046) after adjustment to age, gender, years from symptoms onset, levodopa equivalent daily dose (LEDD) and the NMSS total score at baseline, and the change in LEDD from V0 to V2. Conclusions: In PD patients, the development of MF is associated with a greater increase in the NMS burden after a 2-year follow-up.

Predictors of the change in burden, strain, mood, and quality of life among caregivers of Parkinson's disease patients.

BACKGROUND AND OBJECTIVE: Caregiver burden in Parkinson's disease (PD) has been studied in many cross-sectional studies but poorly in longitudinal ones. The aim of the present study was to analyze the change in burden, strain, mood, and quality of life (QoL) after a 2-year follow-up in a cohort of caregivers of patients with PD and also to identify predictors of these changes. PATIENTS AND METHODS: PD patients and their caregivers who were recruited from January/2016 to November/2017 from 35 centers of Spain from the COPPADIS cohort were included in the study. They were evaluated again at 2-year follow-up. Caregivers completed the Zarit Caregiver Burden Inventory (ZCBI), Caregiver Strain Index (CSI), Beck Depression Inventory-II (BDI-II), and EUROHIS-QOL 8-item index (EUROHIS-QOL8) at baseline (V0) and at 2-year follow-up (V2). General linear model repeated measure and lineal regression models were applied. RESULTS: Significant changes, indicating an impairment, were detected on the total score of the ZCBI (p < 0.0001), CSI (p < 0.0001), BDI-II (p = 0.024), and EUROHIS-QOL8 (p = 0.002) in 192 PD caregivers (58.82 ± 11.71 years old; 69.3% were females). Mood impairment (BDI-II; ß = 0.652; p < 0.0001) in patients from V0 to V2 was the strongest factor associated with caregiver's mood impairment after the 2-year follow-up. Caregiver's mood impairment was the strongest factor associated with an increase from V0 to V2 on the total score of the ZCBI (ß = 0.416; p < 0.0001), CSI (ß = 0.277; p = 0.001), and EUROHIS-QOL (ß = 0.397; p = 0.002). CONCLUSION: Burden, strain, mood, and QoL were impaired in caregivers of PD patients after a 2-year follow-up. Mood changes in both the patient and the caregiver are key aspects related to caregiver burden increase.

Opicapone versus placebo in the treatment of Parkinson's disease patients with end-of-dose motor fluctuation-associated pain: rationale and design of the randomised, double-blind OCEAN (OpiCapone Effect on motor fluctuations and pAiN) trial.

BACKGROUND: Optimisation of dopaminergic therapy may alleviate fluctuation-related pain in Parkinson's disease (PD). Opicapone (OPC) is a third-generation, once-daily catechol-O-methyltransferase inhibitor shown to be generally well tolerated and efficacious in reducing OFF-time in two pivotal trials in patients with PD and end-of-dose motor fluctuations. The OpiCapone Effect on motor fluctuations and pAiN (OCEAN) trial aims to investigate the efficacy of OPC 50 mg in PD patients with end-of-dose motor fluctuations and associated pain, when administered as adjunctive therapy to existing treatment with levodopa/dopa decarboxylase inhibitor (DDCi). METHODS: OCEAN is a Phase IV, international, multicentre, randomised, double-blind, placebo-controlled, parallel-group, interventional trial in PD patients with end-of-dose motor fluctuations and associated pain. It consists of a 1-week screening period, 24-week double-blind treatment period and 2-week follow-up period. Eligible patients will be randomised 1:1 to OPC 50 mg or placebo once daily while continuing current treatment with levodopa/DDCi and other chronic, stable anti-PD and/or analgesic treatments. The primary efficacy endpoint is change from baseline in Domain 3 (fluctuation-related pain) of the King's Parkinson's disease Pain Scale (KPPS). The key secondary efficacy endpoint is change from baseline in Domain B (anxiety) of the Movement Disorder Society-sponsored Non-Motor rating Scale (MDS-NMS). Additional secondary efficacy assessments include other domains and total scores of the KPPS and MDS-NMS, the Parkinson's Disease Questionnaire (PDQ-8), the MDS-sponsored Unified Parkinson's Disease Rating Scale (MDS-UPDRS) Parts III and IV, Clinical and Patient's Global Impressions of Change, and change in functional status via Hauser's diary. Safety assessments include the incidence of treatment-emergent adverse events. The study will be conducted in approximately 140 patients from 50 clinical sites in Germany, Italy, Portugal, Spain and the United Kingdom. Recruitment started in February 2021 and the last patient is expected to complete the study by late 2022. DISCUSSION: The OCEAN trial will help determine whether the use of adjunctive OPC 50 mg treatment can improve fluctuation-associated pain in PD patients with end-of-dose motor fluctuations. The robust design of OCEAN will address the current lack of reliable evidence for dopaminergic-based therapy in the treatment of PD-associated pain. TRIAL REGISTRATION: EudraCT number 2020-001175-32 ; registered on 2020-08-07.

Parkinson's Disease Motor Subtypes Change with the Progression of the Disease: Results from the COPPADIS Cohort at 2-Year Follow-Up.

BACKGROUND: Motor phenotype (MP) can be associated with a different prognosis in Parkinson's disease (PD), but it is not fixed and can change over time. OBJECTIVE: Our aim was to analyze how the MP changed over time and to identify factors associated with the changes in PD patients from a multicenter Spanish PD cohort. METHODS: PD patients who were recruited from January-2016 to November-2017 (baseline visit; V0) and evaluated again at a 2-year±30 days follow-up (V2) from 35 centers of Spain from the COPPADIS cohort, were included in this study.MP was calculated at both visits based on Jankovic classification in TD (tremor dominant), IND (indeterminate), or PIGD (postural instability and gait difficulty). Sociodemographic and clinical data were collected, including serum biomarkers. RESULTS: Five hundred eleven patients (62.57±8.59 years old; 59.2%males) were included in the study. At V0, MP was: 47.4%(242/511) TD; 36.6%(187/511) PIGD; 16%(82/511) IND. Up to 38%(194/511) of the patients changed their phenotype from V0 to V2, being the most frequent from TD to IND (8.4%) and from TD to PIGD (6.7%). A worse cognitive status (OR = 0.966) and less autonomy for activities of daily living (OR  =  0.937) at V0 and a greater increase in the globalNMS burden (OR  =  1.011) from V0 to V2 were associated with changing from TD to another phenotype after 2-year follow-up. CONCLUSION: The MP in PD can change over time. With disease progression, the percentage of cases with non-tremoric MP increases. PD patients who changed from TD to postural instability and gait difficulty increased NMS burden significantly.

Clinical and demographic characteristics of patients with functional movement disorders: a consecutive cohort study from a specialized clinic.

There is a growing interest in functional movement disorders (FMD). However, epidemiological data from large cohorts of patients with FMD are scarce and come mainly from General Neurology and Movement Disorders Clinics. Recently, specialized FMD clinics have been developed and epidemiological data from such clinics may provide useful information. We aimed to describe the clinical and sociodemographic features of patients diagnosed with FMD at our specialized FMD clinic. A standardized form was used to extract data from electronic records from the first-100 consecutive patients who were evaluated and diagnosed with FMD at our clinic from 2017 to 2019. Mean age was 40.88 ± (14.02) years, 63% females. Most patients were within working-age range, but only 16% were working at the time of consultation. Mean disease duration was 3.74 ± 5.73 years and was longer among men. The most common FMD were gait disturbance (42%), tremor (22%) and dystonia (15%). A precipitating event (mainly physical) was reported by 74%. The onset was mostly acute (83%) and the clinical course fluctuating (62%). Pain (64%) and fatigue (44%) were common comorbidities. Potential joint-hypermobility was present in 21%, mostly women (90%) and related to the presence of dystonia. FMD affects men and women mostly in working-age. Gait disturbance was the most common diagnosis, possibly because it causes a higher level of disability that may lead to consultation in a specialized clinic. Non-motor symptoms (pain and fatigue) were frequent in this cohort. Further data from specialized units may contribute to both understanding and management of FMD.

Constipation Predicts Cognitive Decline in Parkinson's Disease: Results from the COPPADIS Cohort at 2-Year Follow-up and Comparison with a Control Group.

BACKGROUND: Constipation has been linked to cognitive impairment development in Parkinson's disease (PD). OBJECTIVE: Our aim was to analyze cognitive changes observed in PD patients and controls from a Spanish cohort with regards to the presence or not of constipation. METHODS: PD patients and controls recruited from 35 centers of Spain from the COPPADIS cohort from January 2016 to November 2017 were followed-up during 2 years. The change in cognitive status from baseline (V0) to 2-year follow-up was assessed with the PD-CRS (Parkinson's Disease Cognitive Rating Scale). Subjects with a score ≥1 on item 21 of the NMSS (Non-Motor Symptoms Scale) at baseline (V0) were considered as "with constipation". Regression analyses were applied for determining the contribution of constipation in cognitive changes. RESULTS: At V0, 39.7% (198/499) of PD patients presented constipation compared to 11.4% of controls (14/123) (p < 0.0001). No change was observed in cognitive status (PD-CRS total score) neither in controls without constipation (from 100.24±13.72 to 100.27±13.68; p = 0.971) and with constipation (from 94.71±10.96 to 93.93±13.03; p = 0.615). The PD-CRS total score decreased significantly in PD patients with constipation (from 89.14±15.36 to 85.97±18.09; p < 0.0001; Coehn's effect = -0.35) compared to patients without constipation (from 93.92±15.58 to 93.14±17.52; p = 0.250) (p = 0.018). In PD patients, to suffer from constipation at V0 was associated with a decrease in the PD-CRS total score from V0 to V2 (ß= -0.1; 95% CI, -4.36 - -0.27; p = 0.026) and having cognitive impairment at V2 (OR = 1.79; 95% CI, 1.01 - 3.17; p = 0.045). CONCLUSION: Constipation is associated with cognitive decline in PD patients but not in controls.

Predictors of clinically significant quality of life impairment in Parkinson's disease.

Quality of life (QOL) plays an important role in independent living in Parkinson's disease (PD) patients, being crucial to know what factors impact QoL throughout the course of the disease. Here we identified predictors of QoL impairment in PD patients from a Spanish cohort. PD patients recruited from 35 centers of Spain from the COPPADIS cohort from January 2016, to November 2017, were followed up during 2 years. Health-related QoL (HRQoL) and global QoL (GQoL) were assessed with the 39-item Parkinson's disease Questionnaire (PDQ-39) and the EUROHIS-QOL 8-item index (EUROHIS-QOL8), respectively, at baseline (V0) and at 24 months ± 1 month (V2). Clinically significant QoL impairment was defined as presenting an increase (PDQ-39SI) or decrement (EUROHIS-QOL8) at V2 ≥ 10% of the score at baseline (V0). A comparison with a control group was conducted for GQoL. GQoL did not change significantly in PD patients (N = 507; p = 0.686) or in the control group (N = 119; p = 0.192). The mean PDQ-39SI was significantly increased in PD patients (62.7 ± 8.5 years old; 58.8% males; N = 500) by 21.6% (from 16.7 ± 13 to 20.3 ± 16.4; p < 0.0001) at V2. Ninety-three patients (18.6%) presented a clinically significant HRQoL impairment at V2. To be younger (OR = 0.896; 95% CI 0.829-0.968; p = 0.006), to be a female (OR = 4.181; 95% CI 1.422-12.290; p = 0.009), and to have a greater increase in BDI-II (Beck Depression Inventory-II) (OR = 1.139; 95% CI 1.053-1.231; p = 0.001) and NMSS (Non-Motor Symptoms Scale) (OR = 1.052; 95% CI 1.027-1.113; p < 0.0001) total scores from V0 to V2 were associated with clinically significant HRQoL impairment at the 2-year follow-up (Hosmer-Lemeshow test, p = 0.665; R2 = 0.655). An increase in ≥5 and ≥10 points of BDI-II and NMSS total score at V2 multiplied the probability of presenting clinically significant HRQoL impairment by 5 (OR = 5.453; 95% CI 1.663-17.876; p = 0.005) and 8 (OR = 8.217; 95% CI, 2.975-22.696; p = 0.002), respectively. In conclusion, age, gender, mood, and non-motor impairment were associated with clinically significant HRQoL impairment after the 2-year follow-up in PD patients.

Diplopia Is Frequent and Associated with Motor and Non-Motor Severity in Parkinson's Disease: Results from the COPPADIS Cohort at 2-Year Follow-Up.

BACKGROUND AND OBJECTIVE: Diplopia is relatively common in Parkinson's disease (PD) but is still understudied. Our aim was to analyze the frequency of diplopia in PD patients from a multicenter Spanish cohort, to compare the frequency with a control group, and to identify factors associated with it. PATIENTS AND METHODS: PD patients who were recruited from January 2016 to November 2017 (baseline visit; V0) and evaluated again at a 2-year ± 30 days follow-up (V2) from 35 centers of Spain from the COPPADIS cohort were included in this longitudinal prospective study. The patients and controls were classified as "with diplopia" or "without diplopia" according to item 15 of the Non-Motor Symptoms Scale (NMSS) at V0, V1 (1-year ± 15 days), and V2 for the patients and at V0 and V2 for the controls. RESULTS: The frequency of diplopia in the PD patients was 13.6% (94/691) at V0 (1.9% in controls [4/206]; p < 0.0001), 14.2% (86/604) at V1, and 17.1% (86/502) at V2 (0.8% in controls [1/124]; p < 0.0001), with a period prevalence of 24.9% (120/481). Visual hallucinations at any visit from V0 to V2 (OR = 2.264; 95%CI, 1.269-4.039; p = 0.006), a higher score on the NMSS at V0 (OR = 1.009; 95%CI, 1.012-1.024; p = 0.015), and a greater increase from V0 to V2 on the Unified Parkinson's Disease Rating Scale-III (OR = 1.039; 95%CI, 1.023-1.083; p < 0.0001) and Neuropsychiatric Inventory (OR = 1.028; 95%CI, 1.001-1.057; p = 0.049) scores were independent factors associated with diplopia (R2 = 0.25; Hosmer and Lemeshow test, p = 0.716). CONCLUSIONS: Diplopia represents a frequent symptom in PD patients and is associated with motor and non-motor severity.