Body mass index in Parkinson's disease: a meta-analysis

Association of Body Mass Index and Parkinson Disease: A Bidirectional Mendelian Randomization Study

BACKGROUND AND OBJECTIVES

The role of body mass index (BMI) in Parkinson disease (PD) is unclear. Based on the Comprehensive Unbiased Risk Factor Assessment for Genetics and Environment in PD (Courage-PD) consortium, we used 2-sample Mendelian randomization (MR) to replicate a previously reported inverse association of genetically predicted BMI with PD and investigated whether findings were robust in analyses addressing the potential for survival and incidence-prevalence biases. We also examined whether the BMI-PD relation is bidirectional by performing a reverse MR.

METHODS

We used summary statistics from a genome-wide association study (GWAS) to extract the association of 501 single-nucleotide polymorphisms (SNPs) with BMI and from the Courage-PD and international Parkinson Disease Genomics Consortium (iPDGC) to estimate their association with PD. Analyses are based on participants of European ancestry. We used the inverse-weighted method to compute odds ratios (ORIVW per 4.8 kg/m2 [95% CI]) of PD and additional pleiotropy robust methods. We performed analyses stratified by age, disease duration, and sex. For reverse MR, we used SNPs associated with PD from 2 iPDGC GWAS to assess the effect of genetic liability toward PD on BMI.

RESULTS

Summary statistics for BMI are based on 806,834 participants (54% women). Summary statistics for PD are based on 8,919 (40% women) cases and 7,600 (55% women) controls from Courage-PD, and 19,438 (38% women) cases and 24,388 (51% women) controls from iPDGC. In Courage-PD, we found an inverse association between genetically predicted BMI and PD (ORIVW 0.82 [0.70-0.97], p = 0.012) without evidence for pleiotropy. This association tended to be stronger in younger participants (≤67 years, ORIVW 0.71 [0.55-0.92]) and cases with shorter disease duration (≤7 years, ORIVW 0.75 [0.62-0.91]). In pooled Courage-PD + iPDGC analyses, the association was stronger in women (ORIVW 0.85 [0.74-0.99], p = 0.032) than men (ORIVW 0.92 [0.80-1.04], p = 0.18), but the interaction was not statistically significant (p-interaction = 0.48). In reverse MR, there was evidence for pleiotropy, but pleiotropy robust methods showed a significant inverse association.

DISCUSSION

Using an independent data set (Courage-PD), we replicate an inverse association of genetically predicted BMI with PD, not explained by survival or incidence-prevalence biases. Moreover, reverse MR analyses support an inverse association between genetic liability toward PD and BMI, in favor of a bidirectional relation.

Impacts of gait freeze on quality of life in Parkinson's disease, from the perspectives of patients and their carers

BACKGROUND

The World Health Organisation (WHO) reports that morbidity and mortality due to Parkinson's disease (PD) are increasing faster than for other neurodegenerative conditions. People with Parkinson's (PwP) present with a variety of motor symptoms, such as tremor, bradykinesia, and rigidity. Freezing of gait (FoG) is a significant motor symptom that manifests as temporary episodes of inability to move one's feet, despite the intention to walk.

AIMS

This study examined the impact of FoG on quality of life (QoL) within an Irish cohort of PwP, from the perspectives of both PwP and their carers, using validated questionnaires that had been adapted for online use.

METHODS

PwP and their carers were recruited by outreach to the Irish Parkinson's Community. Anonymous online questionnaires were distributed, which combined a demographic survey with several clinically validated surveys, including Freezing of Gait Questionnaire (FoG-Q), Parkinson's Disease Questionnaire 8 (PDQ-8), and Parkinson's Disease Carer Questionnaire (PDQ-C).

RESULTS

There was a strong correlation (p < 0.001) between severity of FoG and lower QoL among PwP. Significant correlation was also found between FoG severity and several motor symptoms, such as postural instability and difficulty with balance, and non-motor symptoms, such as cognitive changes and pain/discomfort. FoG severity correlated with disease progression. Significant correlation was also found between FoG and symptoms, as assessed from the perspective of the patients' carers.

CONCLUSIONS

This study shows that FoG is a significant detriment to the QoL of PwP, from the perspectives of patients and carers. This method of assessing FoG and QoL using online questionnaires has potential to enhance the reach and flexibility of this type of research. These findings will inform future studies on larger cohorts and highlight unmet clinical needs in PwP.

Two sample Mendelian Randomisation using an outcome from a multilevel model of disease progression

Identifying factors that are causes of disease progression, especially in neurodegenerative diseases, is of considerable interest. Disease progression can be described as a trajectory of outcome over time-for example, a linear trajectory having both an intercept (severity at time zero) and a slope (rate of change). A technique for identifying causal relationships between one exposure and one outcome in observational data whilst avoiding bias due to confounding is two sample Mendelian Randomisation (2SMR). We consider a multivariate approach to 2SMR using a multilevel model for disease progression to estimate the causal effect an exposure has on the intercept and slope. We carry out a simulation study comparing a naïve univariate 2SMR approach to a multivariate 2SMR approach with one exposure that effects both the intercept and slope of an outcome that changes linearly with time since diagnosis. The simulation study results, across six different scenarios, for both approaches were similar with no evidence against a non-zero bias and appropriate coverage of the 95% confidence intervals (for intercept 93.4-96.2% and the slope 94.5-96.0%). The multivariate approach gives a better joint coverage of both the intercept and slope effects. We also apply our method to two Parkinson's cohorts to examine the effect body mass index has on disease progression. There was no strong evidence that BMI affects disease progression, however the confidence intervals for both intercept and slope were wide.

Body mass index in patients with Parkinson's disease: a systematic review

Body mass index (BMI) has been found to have an impact on neurodegenerative diseases such as Parkinson's disease (PD). Several studies suggested that patients with PD have a lower BMI compared with controls. However, some studies indicated the differences between patients and controls as statistically insignificant. We performed this meta-analysis to clarify the relationship between BMI and PD based on the studies published from 1975 to April 2023 in the PubMed, Embase, and Cochrane Library databases. In total, 18 case-control studies met the inclusion criteria for meta-analysis. We found a statistically significant difference in mean BMI between patients with PD and healthy controls {standardized mean difference (SMD) [95% confidence interval (CI)] = -0.36 (-0.43, -0.29), P < 0.05}. Regarding sex, seven studies were included in the meta-analysis for female/male patients with PD. The mean BMI was significantly different between males with PD and healthy males [SMD (95% CI) = -0.34 (-0.47, -0.22), P < 0.05]. Moreover, the mean BMI of females with PD was significantly different from that of corresponding healthy females [SMD (95% CI) = -0.44 (-0.57, -0.30), P < 0.05]. The meta-analysis demonstrates a significantly lower BMI in patients with PD, but no gender differences, when compared with their respective healthy individuals.NEW & NOTEWORTHY The meta-analysis demonstrates a significantly lower body mass index in patients with PD, but no gender differences, when compared with their respective healthy individuals.

Unravelling the mechanisms of underweight in Parkinson's disease by investigating into the role of gut microbiome

Approximately half of patients with Parkinson's disease (PD) suffer from unintentional weight loss and are underweight, complicating the clinical course of PD patients. Gut microbiota alteration has been proven to be associated with PD, and recent studies have shown that gut microbiota could lead to muscle wasting, implying a possible role of gut microbiota in underweight PD. In this study, we aimed to (1) investigate the mechanism underlying underweight in PD patients with respect to gut microbiota and (2) estimate the extent to which gut microbiota may mediate PD-related underweight through mediation analysis. The data were adapted from Hill-Burns et al., in which 330 participants (199 PD, 131 controls) were enrolled in the study. Fecal samples were collected from participants for microbiome analysis. 16S rRNA gene sequence data were processed using DADA2. Mediation analysis was performed to quantify the effect of intestinal microbial alteration on the causal effect of PD on underweight and to identify the key bacteria that significantly mediated PD-related underweight. The results showed that the PD group had significantly more underweight patients (body mass index (BMI) < 18.5) after controlling for age and sex. Ten genera and four species were significantly different in relative abundance between the underweight and non-underweight individuals in the PD group. Mediation analysis showed that 42.29% and 37.91% of the effect of PD on underweight was mediated through intestinal microbial alterations at the genus and species levels, respectively. Five genera (Agathobacter, Eisenbergiella, Fusicatenibacter, Roseburia, Ruminococcaceae_UCG_013) showed significant mediation effects. In conclusion, we found that up to 42.29% of underweight PD cases are mediated by gut microbiota, with increased pro-inflammatory bacteria and decreased SCFA-producing bacteria, which indicates that the pro-inflammatory state, disturbance of metabolism, and interference of appetite regulation may be involved in the mechanism of underweight PD.

Impact of weight loss for depressive symptom in mid-stage patients with Parkinson's disease: a 4-year follow-up study

Introduction

Weight loss is one of the non-motor symptoms frequently seen in patients with Parkinson's disease (PwPD). Weight loss in PwPD is known to be negatively associated with motor and other non-motor symptoms and has been shown to influence the prognosis of PD. In this study, we followed weight change over a 4-year period in PwPD at a single institution and investigated the relationship between weight change and patients' motor and non-motor symptoms.

Methods

PwPD who visited our hospital from January 2018 to December 2022 were enrolled. Body weights were measured at two points in 2018 (at the start of observation, 'baseline') and 2022 (at the end of observation, 'end date'). In addition, motor symptoms, disease severity, cognitive function, and psychiatric symptoms were evaluated during the same period, and the relationship with weight loss was examined.

Results

Data of 96 PwPD were available for a 4-year follow-up. At baseline, the mean age was 65.7 ± 10.0 years, the mean disease duration was 6.8 ± 4.0 years, and the mean Hoehn and Yahr stage was 2.4 ± 0.7. Among them, 48 patients (50.0%) had a weight loss of ≥5% from baseline (weight loss group; mean loss was 6.6 ± 2.9 kg). The weight loss group was older (p = 0.031), had a lower Mini-Mental State Examination (MMSE) at baseline (p = 0.019), a significantly lower body mass index (p < 0.001), and a higher Zung Self-Rating Depression Scale (SDS) (p = 0.017) at the end date. There was a negative correlation (γ = -0.349, p < 0.001) between weight change and age, a positive correlation (γ = 0.308, p = 0.002) between weight change and MMSE at baseline, and a negative correlation (γ = -0.353, p < 0.001) between weight change and SDS at the end date. Age-adjusted correlations showed a final negative correlation (γ = -0.331, p = 0.001) between weight change and SDS. MMSE and age-adjusted correlations showed a low negative correlation (γ = -0.333, p = 0.001) between weight change and SDS at the end date.

Conclusion

Weight loss in PwPD in mid-stage was more likely with increasing age, and ≥ 5% weight loss was associated with worsening depression. Further research is needed regarding the significance of weight loss in PwPD.

The evaluation of the nutritional status in Parkinson's disease: geriatric nutritional risk index comparison with mini nutritional assessment questionnaire

OBJECTIVE

The symptoms associated with Parkinson's disease may lead to reduced food consumption and in turn, malnutrition. It is therefore important to apply a reliable nutrition screening tool to evaluate the nutritional status of individuals with Parkinson's disease. This cross-sectional study aims to compare the Mini Nutritional Assessment (MNA) questionnaire and the Geriatric Nutrition Risk Index (GNRI) in the assessment of the nutritional status of individuals with Parkinson's disease, and to evaluate the usability of the GNRI in cases of Parkinson's disease.

METHODS

The study was conducted with 89 individuals over the age of 60 who were diagnosed with Parkinson's disease. Study data were collected using a questionnaire form administered through face-to-face interviews, the MNA-Long Form (MNA-LF), and the GNRI was calculated.

RESULTS

The mean GNRI scores were significantly lower in the participants with malnutrition (106.5 ± 19.4) than in the participants at risk of malnutrition (121.0 ± 10.3) and the participants with no malnutrition (125.3 ± 9.6) according to the MNA-LF (p < 0.001). Although there was a positive correlation between the MNA-LF and the GNRI scores, this correlation was not significant (p = 0.095).

CONCLUSIONS

This is the first study to research the nutritional status of individuals with Parkinson's disease using the GNRI. The malnutrition rate detected by GNRI was found to be lower than MNA in Parkinson's patients receiving outpatient treatment. Similar studies are recommended to determine the usability of GNRI on inpatients.

The incidence of deep venous thrombosis in Parkinson's disease

INTRODUCTION

Venous thromboembolism is one of the causes of sudden death in Parkinson's Disease (PD). Few studies have investigated the correlation between PD and deep venous thrombosis (DVT). This study aimed to investigate the frequency of DVT in PD patients prospectively.

MATERIAL AND METHOD

Demographic characteristics of 37 PD patients without known risk factors for DVT, disease duration, Hoehn-Yahr (H - Y) stage, oxygen saturation (SpO2) and heart rate values with pulse oximetry, use of assistive devices, waist and knee circumference measurements, and modified Medical Research Council (mMRC) dyspnea score was recorded. Both legs were evaluated for thrombus by Doppler venous ultrasound (US).

RESULTS

With the H-Y stage of the disease duration, a positive correlation was determined between the H-Y stage and mMRC. Disease duration was negatively correlated with BMI and positively correlated with the need for assistance. Assistive device use was positively associated with age and mMRC. DVT was detected in only one patient. When our patients' files were reviewed after 1.5 years, one patient was hospitalized with the diagnosis of submassive pulmonary embolism.

CONCLUSION

Attention should be paid to the development of DVT in elderly patients with advanced stages of PD, progression in the H-Y stage, use of assistive devices, and progression in dyspnea scoring. There is also a need for studies on the benefit of DVT prophylaxis in PD patients with a high risk of venous thromboembolism.

Adult Spinal Deformity Correction in Patients with Parkinson Disease: Assessment of Surgical Complications, Reoperation, and Cost

BACKGROUND

Parkinson disease (PD) is a neurodegenerative disorder that manifests with postural instability and gait imbalance. Correction of spinal deformity in patients with PD presents unique challenges.

METHODS

The PearlDiver database was queried between 2010 and 2020 to identify adult patients with spinal deformity before undergoing deformity correction with posterior spinal fusion. Two cohorts were created representing patients with and without a preoperative diagnosis of PD. Outcome measures included reoperation rates, surgical technique, cost, surgical complications, and medical complications. Multivariable logistic regression adjusting for Charlson Comorbidity Index, age, gender, 3-column osteotomy, pelvic fixation, and number of levels fused was used to assess rates of reoperation and complications.

RESULTS

In total, 26,984 patients met the inclusion criteria and were retained for analysis. Of these patients, 725 had a diagnosis of PD before deformity correction. Patients with PD underwent higher rates of pelvic fixation (odds ratio [OR], 1.33; P < 0.001) and 3-column osteotomies (OR, 1.53; P < 0.001). On adjusted regression, patients with PD showed increased rates of reoperation at 1 year (OR, 1.37; P < 0.001), 5 years (OR, 1.32; P < 0.001), and overall (OR, 1.33; P < 0.001). Patients with PD also experienced an increased rate of medical complications within 30 days after deformity correction including deep venous thrombosis (OR, 1.60; P = 0.021), pneumonia (OR, 1.44; P = 0.039), and urinary tract infections (OR, 1.54; P < 0.001). Deformity correction in patients with PD was associated with higher 90-day cost (P = 0.007).

CONCLUSIONS

Patients with PD undergoing long fusion for deformity correction are at significantly increased risk of 30-day medical complications and revision procedures after 1 year, controlling for comorbidities, age, and invasiveness. Surgeons should consider the risk of complications, subsequent revision procedures, and increased cost.

Weight and survival after deep brain stimulation for Parkinson's disease

BACKGROUND

Weight loss in Parkinson's disease (PD) is common and associated with increased mortality. The clinical significance of weight changes following deep brain stimulation (DBS) of the subthalamic nucleus (STN) and globus pallidus internus (GPi) is unclear.

OBJECTIVES

To address (1) whether PD patients exhibit progressive weight loss, (2) whether staged DBS surgery is associated with weight changes, and (3) whether survival after DBS correlates with post-DBS weight.

METHODS

This is a single-center, longitudinal, retrospective cohort study of 1625 PD patients. We examined trends in weight over time and the relationship between weight and years survival after DBS using regression and mixed model analyses.

RESULTS

There was a decline in body weight predating motor symptom onset (n = 756, 0.70 ± 0.03% decrease per year, p < 0.001). Weight decline accelerated in the decade preceding death (n = 456, 2.18 ± 0.31% decrease per year, p < 0.001). DBS patients showed a weight increase of 2.0 ± 0.33% at 1 year following the first DBS lead implant (n = 455) and 2.68 ± 1.1% at 3 years if a contralateral DBS lead was placed (n = 249). The bilateral STN DBS group gained the most weight after surgery during 6 years of follow up (vs bilateral GPi, 3.03 ± 0.45% vs 1.89 ± 0.31%, p < 0.01). An analysis of the DBS cohort with date of death available (n = 72) revealed that post-DBS weight (0-12 months after the first or 0-36 months after the second surgery) was positively associated with survival (R2 = 0.14, p < 0.001).

DISCUSSION

Though PD is associated with significant weight loss, DBS patients gained weight following surgery. Higher post-operative weight was associated with increased survival. These results should be replicated in other cohorts.

Bidirectional association between Parkinson's disease and obstructive sleep apnea: a cohort study

STUDY OBJECTIVES

Chronic intermittent hypoxia due to obstructive sleep apnea (OSA) causes oxidative stress, which may contribute to the pathophysiology of Parkinson's disease (PD). However, the bidirectional relationship between PD and OSA has not been satisfactorily established. The objective of this study was to try to estimate whether there is a bidirectional relationship between PD and OSA through a retrospective cohort study in the South Korean population.

METHODS

This study used data from the Korean National Health Information Database of the National Health Insurance Service, which contains data from 3.5 million individuals evenly distributed. In study 1, patients with OSA were matched in a 1:2 ratio with non-OSA controls. In study 2, patients with PD were matched in a 1:2 ratio with non-PD controls. A stratified Cox proportional hazards model was used to calculate hazard ratios.

RESULTS

In study 1, which included 6,396 patients with OSA and 12,792 non-OSA controls, the incidence of PD per 10,000 person-years was 11.59 in the OSA group and 8.46 in the non-OSA group. The OSA group demonstrated a 1.54-fold higher incidence of PD than the non-OSA group (95% confidence interval, 1.14-2.07; P < .05). In study 2, which included 3,427 patients with PD and 6,854 non-PD controls, the incidence of OSA per 10,000 person-years was 14.97 in the PD group and 7.72 in the non-PD group. The PD group demonstrated a 1.92-fold higher incidence of OSA than the non-PD group (95% confidence interval, 1.32-2.78; P < .05).

CONCLUSIONS

This study supports a possible bidirectional relationship between PD and OSA.

CITATION

Jeon S-H, Hwang YS, Oh S-Y, et al. Bidirectional association between Parkinson's disease and obstructive sleep apnea: a cohort study. J Clin Sleep Med. 2023;19(9):1615-1623.

Diet quality, sleep and quality of life in Parkinson's disease: a cross-sectional study

BACKGROUND

Parkinson's disease (PD) is a neurodegenerative disorder characterised by motor and non-motor symptoms that impact quality of daily life, including diet and sleep. However, relatively little is known about dietary intake and quality in people with PD (PwP). Lifestyle factors, and how they relate to diet, are also insufficiently understood. The aims of this study were to investigate dietary intake and quality, sleep and quality of life in PwP, and to explore the relationships between these factors.

METHODS

Forty-five community-dwelling participants with PD (n = 45) were recruited to this cross-sectional study through the Cork Parkinson's Association, Ireland. Dietary intake was assessed using the EPIC food frequency questionnaire, and diet quality was assessed using the Healthy Diet Indicator. Dietary intakes were compared to Irish RDAs for adults > 65 years. Sleep duration and quality were subjectively measured using the PD Sleep Scale and Pittsburgh sleep quality index and objectively measured by actigraphy in a subset of participants (n = 27). QOL was measured using the validated PDQ-39 questionnaire.

RESULTS

Energy intake in PwP was significantly higher than that of the general population (2013 vs 1755 kcal/d, p = 0.01), despite their lower mean BMI (25.9 vs 27.7 kg/m2, p = 0.02). Intakes of carbohydrate, protein and fruits and vegetables were significantly higher in PwP compared to recommended and population intakes (all p < 0.01), but fibre intake was significantly lower than recommended (17.3 vs 25 g/d, p [Formula: see text] 0.05). Seventy-eight percent of participants had poor dietary quality, and poor sleep quality was associated with poor QOL.

CONCLUSIONS

Carbohydrates, protein, fruit and vegetable intakes were greater in PwP than population norms, but overall diet quality was low. Interventions to improve dietary and lifestyle factors may improve health and QOL in PwP.

Chaudhuri's Dashboard of Vitals in Parkinson's syndrome: an unmet need underpinned by real life clinical tests

We have recently published the notion of the "vitals" of Parkinson's, a conglomeration of signs and symptoms, largely nonmotor, that must not be missed and yet often not considered in neurological consultations, with considerable societal and personal detrimental consequences. This "dashboard," termed the Chaudhuri's vitals of Parkinson's, are summarized as 5 key vital symptoms or signs and comprise of (a) motor, (b) nonmotor, (c) visual, gut, and oral health, (d) bone health and falls, and finally (e) comorbidities, comedication, and dopamine agonist side effects, such as impulse control disorders. Additionally, not addressing the vitals also may reflect inadequate management strategies, leading to worsening quality of life and diminished wellness, a new concept for people with Parkinson's. In this paper, we discuss possible, simple to use, and clinically relevant tests that can be used to monitor the status of these vitals, so that these can be incorporated into clinical practice. We also use the term Parkinson's syndrome to describe Parkinson's disease, as the term "disease" is now abandoned in many countries, such as the U.K., reflecting the heterogeneity of Parkinson's, which is now considered by many as a syndrome.

Body Mass Index, Abdominal Adiposity, and Incidence of Parkinson Disease in French Women From the E3N Cohort Study

BACKGROUND AND OBJECTIVES

Previous studies on the relationship between body mass index (BMI) and Parkinson disease (PD) provided inconsistent results, likely due to reverse causation explained by weight loss during the prodromal phase. We examined the association of BMI and abdominal adiposity with PD incidence using lagged analyses to address the potential for reverse causation and compared BMI trajectories in patients before diagnosis and matched controls.

METHODS

We used data from the E3N cohort study of French women with a 29-year follow-up (1990-2018). BMI (kg/m²) was computed based on self-reported weight and height up to 11 times; up to 6 waist circumference (WC) and hip circumference measures were available. PD diagnoses were validated based on medical records and drug claim databases. Multivariable time-varying Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% CIs according to BMI categories (underweight <18.5 kg/m²; normal = [18.5-25.0[ kg/m²; overweight = [25.0-30.0[ kg/m²; obese ≥30.0 kg/m²). Exposures were lagged by 5 years in main analyses; we used longer lags (10 and 20 years) in sensitivity analyses. We examined trajectories of BMI categories within a nested case-control study using multivariable generalized estimating equations multinomial logistic models.

RESULTS

Of 96,702 women (baseline age = 40-65 years), 1,164 developed PD. PD incidence was lower (HR = 0.76, 95% CI = 0.59-0.98, p = 0.032) among women with obesity compared with those with normal BMI. There was a similar association in analyses using longer lag times (20 years, 598 cases, HR = 0.52, 95% CI = 0.30-0.88, p = 0.016). A similar pattern was seen for WC and waist-height ratio but not waist-hip ratio. Trajectories of BMI categories (1,196 patients and 23,876 controls) showed that obesity was less frequent in patients with PD before diagnosis than in controls, with a statistically significant difference 29 years before. In addition, the frequency of obesity decreased 5-10 years before diagnosis in patients.

DISCUSSION

In this large cohort of women with a long follow-up, obesity was associated with a lower hazard of PD, even when measured 20 years before diagnosis, in agreement with Mendelian randomization studies. Our analyses underscore the importance of lagged analyses to account for reverse causation. These findings warrant further investigations to understand the mechanisms underlying this inverse association.

Validation of STOP, STOP-BANG, STOP-BAG, STOP-B28, and GOAL screening tools for identification of obstructive sleep apnea in patients with Parkinson disease

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is common in Parkinson disease (PD). Questionnaires can be used as screening tools and have been used as a surrogate definition of OSA in large-scale research. This study aimed to validate the performance of STOP, STOP-BANG, STOP-BAG, STOP-B28, and GOAL and OSA predictors as tools to identify OSA in PD.

METHODS

Data were analyzed from a PD cohort study in which OSA was diagnosed using laboratory polysomnography. We calculated sensitivity and specificity of each questionnaire for OSA using different definitions and performed receiver operating characteristics curve analysis. Linear regression was used to assess adjusted associations between questionnaires and outcomes: Montreal Cognitive Assessment, Epworth Sleepiness Scale, and Movement Disorder Society revision of the Unified Parkinson Disease Rating Scale.

RESULTS

Questionnaire data were available for 68 PD patients (61.8% male, mean age 64.5 [standard deviation 9.9] years, and Hoehn and Yahr score 2.1 [0.8]). OSA (apnea-hypopnea index ≥ 15 events/h) occurred in 69.4% of participants. STOP-B28 ≥ 2 presented a higher sensitivity for OSA than STOP ≥ 2 (0.76 vs 0.65, respectively) and slightly lower specificity (0.65 vs 0.70, respectively). GOAL ≥ 2 had the highest sensitivity but poor specificity. Loud snoring had sensitivity 0.63 and specificity 0.65. STOP and snoring were significantly associated with Montreal Cognitive Assessment, Epworth Sleepiness Scale, and Movement Disorder Society revision of the Unified Parkinson Disease Rating Scale (total, motor, and nonmotor); STOP-BANG, STOP-BAG, and STOP-B28 showed associations with most outcomes, but the GOAL showed none.

CONCLUSIONS

The STOP-B28 followed by STOP and presence of loud snoring alone seem to have the best overall properties to identify PD patients with OSA, whose clinical characteristics differ from the general population with OSA.

CITATION

Gomes T, Benedetti A, Lafontaine A-L, Kimoff RJ Robinson A, Kaminska M. Validation of STOP, STOP-BANG, STOP-BAG, STOP-B28, and GOAL screening tools for identification of obstructive sleep apnea in patients with Parkinson disease. J Clin Sleep Med. 2023;19(1):45-54.

Low serum uric acid levels and levodopa-induced dyskinesia in Parkinson's disease

BACKGROUND

Levodopa is the most used and effective medication for motor symptoms of Parkinson disease (PD), its long-term use is associated with the appearance of levodopa-induced dyskinesia (LID). Uric acid (UA) is believed to play an important neuroprotective role in PD.

OBJECTIVE

To investigate if serum UA levels are related with the presence of LIDs in PD patients. Also, we investigated the associations among UA levels and clinical features of PD.

METHODS

We enrolled 81 PD patients (dyskinesia = 48; no dyskinesia = 33) in the present study. A blood sample was collected to evaluate serum UA levels, clinical evaluation included the following instruments: Montreal Cognitive Assessment (MoCA), Beck Depression Inventory II (BDI-II), MDS-Unified Parkinson's Disease Rating Scale (MDS-UPDRS), Hoehn and Yahr (HY), and the sub-item 4.1 of MDS-UPDRS IV (score ≥ 1). Additional relevant clinical information was obtained by a clinical questionnaire.

RESULTS

Serum UA levels were lower in the dyskinesia group when compared with the no dyskinesia group. The same result was found in the UA levels of both men and women. The multivariate analysis showed lower uric acid levels were significantly associated with having dyskinesia (odds ratio [OR] = 0.424; 95% confidence interval [CI]: 0.221-0.746; p = 0.005). Additional analysis verified that serum UA levels are inversely correlated with depressive symptoms, disease duration, MDS-UPDRS IV and time spent with dyskinesia. A positive correlation was found with age at onset of PD symptoms.

CONCLUSIONS

The present study provides a possible role of serum UA levels in LID present in PD patients.

Long-term air pollution exposure and Parkinson's disease mortality in a large pooled European cohort: An ELAPSE study

BACKGROUND

The link between exposure to ambient air pollution and mortality from cardiorespiratory diseases is well established, while evidence on neurodegenerative disorders including Parkinson's Disease (PD) remains limited.

OBJECTIVE

We examined the association between long-term exposure to ambient air pollution and PD mortality in seven European cohorts.

METHODS

Within the project 'Effects of Low-Level Air Pollution: A Study in Europe' (ELAPSE), we pooled data from seven cohorts among six European countries. Annual mean residential concentrations of fine particulate matter (PM_2.5), nitrogen dioxide (NO₂), black carbon (BC), and ozone (O₃), as well as 8 PM_2.5 components (copper, iron, potassium, nickel, sulphur, silicon, vanadium, zinc), for 2010 were estimated using Europe-wide hybrid land use regression models. PD mortality was defined as underlying cause of death being either PD, secondary Parkinsonism, or dementia in PD. We applied Cox proportional hazard models to investigate the associations between air pollution and PD mortality, adjusting for potential confounders.

RESULTS

Of 271,720 cohort participants, 381 died from PD during 19.7 years of follow-up. In single-pollutant analyses, we observed positive associations between PD mortality and PM_2.5 (hazard ratio per 5 µg/m³: 1.25; 95% confidence interval: 1.01-1.55), NO₂ (1.13; 0.95-1.34 per 10 µg/m³), and BC (1.12; 0.94-1.34 per 0.5 × 10^-5m^-1), and a negative association with O₃ (0.74; 0.58-0.94 per 10 µg/m³). Associations of PM_2.5, NO₂, and BC with PD mortality were linear without apparent lower thresholds. In two-pollutant models, associations with PM_2.5 remained robust when adjusted for NO₂ (1.24; 0.95-1.62) or BC (1.28; 0.96-1.71), whereas associations with NO₂ or BC attenuated to null. O₃ associations remained negative, but no longer statistically significant in models with PM_2.5. We detected suggestive positive associations with the potassium component of PM_2.5.

CONCLUSION

Long-term exposure to PM_2.5, at levels well below current EU air pollution limit values, may contribute to PD mortality.

[Lower gastrointestinal dysfunction in patients with Parkinson's disease]

OBJECTIVE

To assess the lower gastrointestinal tract dysfunction in patients with Parkinson's disease (PD) and to reveal its relationships with motor and non-motor symptoms.

MATERIAL AND METHODS

One hundred and eighteen patients with PD of I-III Hoehn and Yahr (H&Y) stages were studied using UPDRSI-IV, Sch&En, PDQ-39, MMSE, BDI, STAI-S and STAI-T, PFS-16, NMSQ, GSRS, BSFS, AUA. Body mass index and saliva amount and lacrimation (Schirmer's test) were assessed.

RESULTS

Constipation from mild to moderate intensity was present in 71.2% of the patients; predominantly mild diarrhea occurred in 27.9%; alternations of diarrhea with the difficulty in intestine emptying were observed in 25.4%. We found significant correlations of constipation with the following parameters: Sch&En scales (rS=-0.291) and PDQ-39 (rS=0.478), patient's age (rS=0.275), H&Y stage (rS=0.2604), UPDRS (rS=0.254), axial motor symptoms of parkinsonism, and a number of affective and autonomic disorders, most of which were partly dopamine-resistant. Diarrhea did not affect the quality of patient's life, or depend on age, PD stage, main digital and non-motor symptoms, but directly correlated with the severity of constipation (rS=0.263) and other gastrointestinal disorders. There were no effects of dopaminergic therapy, including levodopa, dopamine-receptor-agonists, and amantadine, on the lower gastrointestinal tract dysfunction.

CONCLUSION

Dysfunction of the lower gastrointestinal tract (predominantly from mild to moderate intensity) was detected in most PD patients of I-III stages. Our data indicate a complex pathogenesis of the PD impaired bowel emptying, involving degeneration of non-dopaminergic structures, and the predominant influence of concomitant diseases and inadequate laxative therapy on the formation of diarrhea syndrome in PD.

Effect Modification between Genes and Environment and Parkinson's Disease Risk

Parkinson's disease (PD) is a complex neurodegenerative condition in which genetic and environmental factors interact to contribute to its etiology. Remarkable progress has been made in deciphering disease etiology through genetic approaches, but there is limited data about how environmental and genetic factors interact to modify penetrance, risk, and disease severity. Here, we provide insights into environmental modifiers of PD, discussing precedents from other neurological and non-neurological conditions. Based on these examples, we outline genetic and environmental factors contributing to PD and review potential environmental modifiers of penetrance and clinical variability in monogenic and idiopathic PD. We also highlight the potential challenges and propose how future studies might tackle these important questions. ANN NEUROL 2022;92:715-724.

Initial BMI and Weight Loss Over Time Predict Mortality in Parkinson Disease

OBJECTIVES

Although weight loss is a frequent symptom in Parkinson disease (PD), there have been few studies on the association between body mass index (BMI) and mortality. The objective of this study was to investigate the association between BMI and change in BMI at diagnosis in patients with PD and all-cause mortality.

DESIGN

Cohort study using Korean National Health Insurance Service-Elderly Cohort data.

SETTING AND PARTICIPANTS

Patients with new-onset PD were selected using the International Classification of Diseases 10th edition code (G20). Then, patients who were diagnosed more than 3 times with PD and had been prescribed anti-parkinsonian medication for ≥30 days were included. Those with a combined diagnosis of atypical parkinsonism and secondary parkinsonism were excluded.

METHODS

The primary outcome was all-cause mortality. Anthropometric data, including height and weight, were obtained from the health screening data to calculate BMI. The Cox proportional hazards model was used to assess mortality risk by BMI.

RESULTS

Among the 2703 patients with PD, 492 (18.20%) died during the 11-year follow-up period. There was a significant inverse dose-response relationship between baseline BMI and mortality (<18.5 kg/m²: hazard ratio [HR], 1.872, 95% CI, 1.338-2.494; 23-25 kg/m²: HR, 0.695, 95% CI, 0.546-0.886; 25-30 kg/m²: HR, 0.644, 95% CI, 0.476-0.869; ≥30 kg/m²: HR, 0.396, 95% CI, 0.165-0.950). Change in BMI of 10% revealed a significant association with mortality. Subgroup analyses by sex showed a significant inverse dose-response relationship between BMI and all-cause mortality only in women.

CONCLUSIONS AND IMPLICATIONS

We demonstrated an inverse dose-response association between BMI at diagnosis and mortality in patients with PD, especially in women. Early detection of PD before weight loss progression and proper management might improve mortality. The small number of obese PD participants in our study should be considered when interpreting and generalizing results.

Needs of patients with parkinsonism and their caregivers: a protocol for the PRIME-UK cross-sectional study

INTRODUCTION

People with parkinsonism are a highly heterogeneous group and the disease encompasses a spectrum of motor and non-motor symptoms which variably emerge and manifest across the disease course, fluctuate over time and negatively impact quality of life. While parkinsonism is not directly the result of ageing, it is a condition that mostly affects older people, who may also be living with frailty and multimorbidity. This study aims to describe the broad range of health needs for people with parkinsonism and their carers in relation to their symptomatology, disability, disease stage, comorbidities and sociodemographic characteristics.

METHODS AND ANALYSIS

In this single site cross-sectional study, people with parkinsonism will be sent a study information pack for themselves and their primary informal caregiver, if relevant. Data are collected via questionnaire, with additional support, if required, to maximise participation. A specific strategy has been developed to target and proactively recruit patients lacking capacity to consent, including those in residential care settings, with input from a personal consultee prior to completion of a bespoke questionnaire by a representative. Caregivers are also recruited to look at various health outcomes. Results will be displayed as descriptive statistics and regression models will be used to test simple associations and interactions.

ETHICS AND DISSEMINATION

This protocol was approved by the London-Brighton & Sussex Research Ethics Committee (REC reference 20/LO/0890). The results of this protocol will be disseminated through publication in an international peer-reviewed journal; presentation at academic meetings and conferences; and a lay summary uploaded to the PRIME-Parkinson website.

TRIAL REGISTRATION NUMBER

ISRCTN11452969; Pre-results.

Assessment of Risk Factors and Early Presentations of Parkinson Disease in Primary Care in a Diverse UK Population

IMPORTANCE

Early features of Parkinson disease (PD) have been described through population-based studies that overrepresent White, affluent groups and may not be generalizable.

OBJECTIVE

To investigate the association between risk factors and prediagnostic presentations of PD in an ethnically diverse UK population with high socioeconomic deprivation but universal access to health care.

DESIGN, SETTING, AND PARTICIPANTS

A nested case-control study was conducted using electronic health care records on 1 016 277 individuals from primary care practices in East London to extract clinical information recorded between 1990 and February 6, 2018. The data were analyzed between September 3, 2020, and September 3, 2021. Individuals with a diagnosis of PD were compared with controls without PD or other major neurological conditions.

MAIN OUTCOMES AND MEASURES

A matched analysis (10 controls matched for each patient with PD according to age and sex) and an unmatched analysis (adjusted for age and sex) were undertaken using multivariable logistic regression to determine associations between risk factors and prediagnostic presentations to primary care with subsequent diagnosis of PD. Three time periods (<2, 2-<5, and 5-10 years before diagnosis) were analyzed separately and together.

RESULTS

Of 1 016 277 individuals included in the data set, 5699 were excluded and 1055 patients with PD and 1 009 523 controls were included in the analysis. Patients with PD were older than controls (mean [SD], 72.9 [11.3] vs 40.3 [15.2] years), and more were male (632 [59.9%] vs 516 862 [51.2%]). In the matched analysis (1055 individuals with PD and 10 550 controls), associations were found for tremor (odds ratio [OR], 145.96; 95% CI, 90.55-235.28) and memory symptoms (OR, 8.60; 95% CI, 5.91-12.49) less than 2 years before the PD diagnosis. The associations were also found up to 10 years before PD diagnosis for tremor and 5 years for memory symptoms. Among midlife risk factors, hypertension (OR, 1.36; 95% CI, 1.19-1.55) and type 2 diabetes (OR, 1.39; 95% CI, 1.19-1.62) were associated with subsequent diagnosis of PD. Associations with early nonmotor features, including hypotension (OR, 6.84; 95% CI, 3.38-13.85), constipation (OR, 3.29; 95% CI, 2.32-4.66), and depression (OR, 4.69; 95% CI, 2.88-7.63), were also noted. Associations were found for epilepsy (OR, 2.5; 95% CI, 1.63-3.83) and hearing loss (OR, 1.66; 95% CI, 1.06-2.58), which have not previously been well reported. These findings were replicated using data from the UK Biobank. No association with future PD diagnosis was found for ethnicity or deprivation index level.

CONCLUSIONS AND RELEVANCE

This study provides data suggesting that a range of comorbidities and symptoms are encountered in primary care settings before PD diagnosis in an ethnically diverse and deprived population. Novel temporal associations were observed for epilepsy and hearing loss with subsequent development of PD. The prominence of memory symptoms suggests an excess of cognitive dysfunction in early PD in this population or difficulty in correctly ascertaining symptoms in traditionally underrepresented groups.

Umami and Other Taste Perceptions in Patients With Parkinson's Disease

Objective

Studies of taste perceptions in Parkinson’s disease (PD) patients have been controversial, and none of these studies have assessed umami taste. This study aimed to assess umami, along with the other 4 taste functions in PD patients.

Methods

Participants were tested for gustation using the modified filter paper disc method and olfaction using the modified Sniffin’ Stick-16 (mSS-16) test (only 14 culturally suitable items were used). A questionnaire evaluated patients’ subjective olfactory and gustatory dysfunction, taste preference, appetite, and food habits.

Results

A total of 105 PD patients and 101 age- and sex-matched controls were included. The body mass index (BMI) of PD patients was lower than that of controls (PD = 22.62, controls = 23.86, p = 0.028). The mSS-16 score was 10.7 for controls and 6.4 for PD patients (p < 0.001) (normal ≥ 9). Taste recognition thresholds (RTs) for sweet, salty, sour, bitter and umami tastes were significantly higher in PD, indicating poorer gustation. All taste RTs correlated with each other, except for umami. Most patients were unaware of their dysfunction. Patients preferred sweet, salty and umami tastes more than the controls. Dysgeusia of different tastes in patients was differentially associated with poorer discrimination of tastes, an inability to identify the dish and adding extra seasoning to food. BMI and mSS-16 scores showed no correlation in either patients or controls.

Conclusion

PD patients have dysgeusia for all five tastes, including umami, which affects their appetite and diet. Patients preferred sweet, salty and umami tastes. This information can help adjust patients’ diets to improve their nutritional status.

Hydrogen Sulfide Produced by Gut Bacteria May Induce Parkinson's Disease

Several bacterial species can generate hydrogen sulfide (H2S). Study evidence favors the view that the microbiome of the colon harbors increased amounts of H2S producing bacteria in Parkinson's disease. Additionally, H2S can easily penetrate cell membranes and enter the cell interior. In the cells, excessive amounts of H2S can potentially release cytochrome c protein from the mitochondria, increase the iron content of the cytosolic iron pool, and increase the amount of reactive oxygen species. These events can lead to the formation of alpha-synuclein oligomers and fibrils in cells containing the alpha-synuclein protein. In addition, bacterially produced H2S can interfere with the body urate metabolism and affect the blood erythrocytes and lymphocytes. Gut bacteria responsible for increased H2S production, especially the mucus-associated species of the bacterial genera belonging to the Desulfovibrionaceae and Enterobacteriaceae families, are likely play a role in the pathogenesis of Parkinson's disease. Special attention should be devoted to changes not only in the colonic but also in the duodenal microbiome composition with regard to the pathogenesis of Parkinson's disease. Influenza infections may increase the risk of Parkinson's disease by causing the overgrowth of H2S-producing bacteria both in the colon and duodenum.

Factors Contributing to Malnutrition in Parkinson's Disease Patients With Freezing of Gait

Background and Purpose

Little is known about the nutritional status and clinical characteristics of patients with Parkinson's disease with freezing of gait (PDFOG). The purpose of this study was to describe the relationship between nutritional status and characteristics of patients with PDFOG.

Methods

In this cross-sectional study, 178 PDFOG patients were recruited and classified as nutritionally normal or at risk of malnutrition/already malnourished based on their Mini Nutritional Assessment (MNA) scores. Each participant underwent a structured questionnaire, physical examination and routine serum biochemical tests.

Results

We found that 44.4 and 37.1% of PDFOG patients were malnourished [mini nutritional assessment (MNA) score &lt;17] and at risk of malnutrition (17 ≤ MNA score ≤ 23.5), respectively. Compared to patients with normal nutrition, PDFOG patients with malnutrition and at risk of malnutrition had longer duration of Parkinson's disease (PD) and freezing of gait (FOG), more levodopa equivalent daily doses (LEDD), lower body mass index (BMI), more motor symptoms according to the Unified PD Rating Scale-III (UPDRS-III) and non-motor symptoms according to the PD Non-motor Symptoms Questionnaire (PD-NMS) (P &lt; 0.05). Uric acid, albumin, prealbumin, and total cholesterol (TC) differed between the two groups (P &lt; 0.05). High Hoehn and Yahr (H-Y) stage, high Freezing of Gait Questionnaire (FOGQ) scores, low TC and low uric acid were risk factors for malnutrition in patients with PDFOG.

Conclusion

Our results showed disease severity, motor symptoms, TC levels and uric acid levels were all associated with nutritional status in patients with PDFOG. This study suggest early discovery of the nutritional status of PDFOG patients is important.

Parkinson's disease: the nutrition perspective

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease and affects about 1% of the population over the age of 60 years in industrialised countries. The aim of this review is to examine nutrition in PD across three domains: dietary intake and the development of PD; whole body metabolism in PD and the effects of PD symptoms and treatment on nutritional status. In most cases, PD is believed to be caused by a combination of genetic and environmental factors and although there has been much research in the area, evidence suggests that poor dietary intake is not a risk factor for the development of PD. The evidence about body weight changes in both the prodromal and symptomatic phases of PD is inconclusive and is confounded by many factors. Malnutrition in PD has been documented as has sarcopaenia, although the prevalence of the latter remains uncertain due to a lack of consensus in the definition of sarcopaenia. PD symptoms, including those which are gastrointestinal and non-gastrointestinal, are known to adversely affect nutritional status. Similarly, PD treatments can cause nausea, vomiting and constipation, all of which can adversely affect nutritional status. Given that the prevalence of PD will increase as the population ages, it is important to understand the interplay between PD, comorbidities and nutritional status. Further research may contribute to the development of interventional strategies to improve symptoms, augment care and importantly, enhance the quality of life for patients living with this complex neurodegenerative disease.

Sleep and circadian rhythms in Parkinson's disease and preclinical models

The use of animals as models of human physiology is, and has been for many years, an indispensable tool for understanding the mechanisms of human disease. In Parkinson's disease, various mouse models form the cornerstone of these investigations. Early models were developed to reflect the traditional histological features and motor symptoms of Parkinson's disease. However, it is important that models accurately encompass important facets of the disease to allow for comprehensive mechanistic understanding and translational significance. Circadian rhythm and sleep issues are tightly correlated to Parkinson's disease, and often arise prior to the presentation of typical motor deficits. It is essential that models used to understand Parkinson's disease reflect these dysfunctions in circadian rhythms and sleep, both to facilitate investigations into mechanistic interplay between sleep and disease, and to assist in the development of circadian rhythm-facing therapeutic treatments. This review describes the extent to which various genetically- and neurotoxically-induced murine models of Parkinson's reflect the sleep and circadian abnormalities of Parkinson's disease observed in the clinic.

The Interactions between Adipose Tissue Secretions and Parkinson's disease; The Role of Leptin

Leptin is a hormone that regulates appetite by acting on receptors in the hypothalamus, where it modifies food intake to maintain equilibrium with the body energy resources. Leptin and its receptors are widely distributed in the central nervous system, suggesting that they may give neuronal survival signals. The potential of leptin to decrease/increase neuronal damage and neuronal plasticity in Parkinson's diseases (PD) is the subject of this review, which outlines our current knowledge of how leptin acts in the brain. Although leptin-mediated neuroprotective signaling results in neuronal death prevention, it can affect neuroinflammatory cascades and also neuronal plasticity which contribute to PD pathology. Other neuroprotective molecules, such as insulin and erythropoietin, share leptin-related signaling cascades, and therefore constitute a component of the neurotrophic effects mediated by endogenous hormones. With the evidence that leptin dysregulation causes increased neuronal vulnerability to damage in PD, using leptin as a target for therapeutic modification is an appealing and realistic option.

Constructing Prediction Models for Freezing of Gait by Nomogram and Machine Learning: A Longitudinal Study

Objectives: Although risk factors for freezing of gait (FOG) have been reported, there are still few prediction models based on cohorts that predict FOG. This 1-year longitudinal study was aimed to identify the clinical measurements closely linked with FOG in Chinese patients with Parkinson's disease (PD) and construct prediction models based on those clinical measurements using Cox regression and machine learning. Methods: The study enrolled 967 PD patients without FOG in the Hoehn and Yahr (H&Y) stage 1-3 at baseline. The development of FOG during follow-up was the end-point. Neurologists trained in movement disorders collected information from the patients on a PD medication regimen and their clinical characteristics. The cohort was assessed on the same clinical scales, and the baseline characteristics were recorded and compared. After the patients were divided into the training set and test set by the stratified random sampling method, prediction models were constructed using Cox regression and random forests (RF). Results: At the end of the study, 26.4% (255/967) of the patients suffered from FOG. Patients with FOG had significantly longer disease duration, greater age at baseline and H&Y stage, lower proportion in Tremor Dominant (TD) subtype, a higher proportion in wearing-off, levodopa equivalent daily dosage (LEDD), usage of L-Dopa and catechol-O-methyltransferase (COMT) inhibitors, a higher score in scales of Unified Parkinson's Disease Rate Scale (UPDRS), 39-item Parkinson's Disease Questionnaire (PDQ-39), Non-Motor Symptoms Scale (NMSS), Hamilton Depression Rating Scale (HDRS)-17, Parkinson's Fatigue Scale (PFS), rapid eye movement sleep behavior disorder questionnaire-Hong Kong (RBDQ-HK), Epworth Sleepiness Scale (ESS), and a lower score in scales of Parkinson's Disease Sleep Scale (PDSS) (P < 0.05). The risk factors associated with FOG included PD onset not being under the age of 50 years, a lower degree of tremor symptom, impaired activities of daily living (ADL), UPDRS item 30 posture instability, unexplained weight loss, and a higher degree of fatigue. The concordance index (C-index) was 0.68 for the training set (for internal validation) and 0.71 for the test set (for external validation) of the nomogram prediction model, which showed a good predictive ability for patients in different survival times. The RF model also performed well, the C-index was 0.74 for the test set, and the AUC was 0.74. Conclusions: The study found some new risk factors associated with the FOG including a lower degree of tremor symptom, unexplained weight loss, and a higher degree of fatigue through a longitudinal study, and constructed relatively acceptable prediction models.

Prevalence and associated factors of malnutrition in patients with Parkinson's disease using CONUT and GNRI

OBJECTIVE

Parkinson's disease (PD) is a common neurodegenerative disease, but its nutritional problems have not received enough attention. This study aims to identify the prevalence and associated factors of malnutrition in PD patients using two simple nutritional tools.

METHODS

We conducted a large-scale cross-sectional study with 1478 PD patients and equal healthy controls (HC). The controlling nutritional status score (CONUT) and geriatric nutritional risk index (GNRI) were used for malnutrition stratification.

RESULTS

By CONUT or GNRI, the prevalence of malnutrition in PD patients was higher than that in HC (40.7% vs. 25.3% and 11.1% vs. 2.1%, respectively). The binary logistic regression model showed that malnutrition in PD was associated with male sex (OR = 0.600, P < 0.001), older age (OR = 1.015, P = 0.003), lower body mass index (BMI) (OR = 0.942, P < 0.001), higher levodopa equivalent daily doses (LEDD) (OR = 1.001, P < 0.001), worse motor symptoms (OR = 1.012, P = 0.004), more serious perceptual problems/hallucinations (OR = 1.067, P = 0.019) by CONUT. In comparison, older age (OR = 1.045, P < 0.001), lower blood lymphocyte count (OR = 0.607, P = 0.006), lower serum total cholesterol levels (OR = 0.991, P < 0.001), dyskinesia (OR = 2.231, P = 0.002), worse motor symptoms (OR = 1.016, P = 0.015), more severe depression (OR = 1.028, P = 0.008) and perceptual problems/hallucinations (OR = 1.061, P = 0.033) were associated with malnutrition in PD by GNRI.

CONCLUSIONS

Our study indicated that malnutrition is more prevalent in PD patients than HC. Multidimensional risk factors for malnutrition in PD should be taken seriously.

Changes in Body Composition Before and After Parkinson's Disease Diagnosis

BACKGROUND

Weight loss is common in Parkinson's disease (PD). However, little is known about when it starts, how PD changes as it progresses, and whether there is a differential loss of lean or fat mass. The objective of this study was to examine how body composition changes before and after PD diagnosis.

METHODS

In the Health, Aging, and Body Composition study (n = 3075; age range, 70-79 years), body composition was assessed using dual-energy x-ray absorptiometry on an annual or biennial basis from year 1 to year 10. For each PD case each year, we calculated the difference between their actual body composition measures and expected values had they not developed PD. Using linear mixed models with crossed random effects, we further examined the trend of change in body composition measures before and after PD diagnosis.

RESULTS

A total of 80 PD cases were identified in this cohort. Compared with their expected values, PD cases began to lose total and fat mass about 6-7 years before diagnosis, although the differences were not statistically significant until 3-5 years after diagnosis. The loss was substantial and persistent, with statistically significant trends of loss for total body mass (P = 0.008), fat mass (P = 0.001), and percentage fat (P < 0.001). In comparison, lean mass was stable throughout the follow-up (P = 0.16). Overall, 96% of the body mass loss in PD cases was from the loss of fat mass.

CONCLUSIONS

In this longitudinal analysis with objective measures of body composition, we found persistent weight loss in PD cases, predominantly in fat mass, starting a few years before diagnosis. © 2021 International Parkinson and Movement Disorder Society.

Increased Added Sugar Consumption Is Common in Parkinson's Disease

Objectives: There is limited information about the dietary habits of patients with Parkinson's Disease (PD), or associations of diet with clinical PD features. We report on nutritional intake in an Australian PD cohort.

Methods: 103 PD patients and 81 healthy controls (HCs) completed a validated, semi-quantitative food frequency questionnaire. Food and nutrient intake was quantified, with consideration of micronutrients and macronutrients (energy, protein, carbohydrate, fat, fibre, and added sugar). Participants also completed PD-validated non-motor symptom questionnaires to determine any relationships between dietary intake and clinical disease features.

Results: Mean daily energy intake did not differ considerably between PD patients and HCs (11,131 kJ/day vs. 10,188 kJ/day, p = 0.241). However, PD patients reported greater total carbohydrate intake (279 g/day vs. 232 g/day, p = 0.034). This was largely attributable to increased daily sugar intake (153 g/day vs. 119 g/day, p = 0.003) and in particular free sugars (61 g/day vs. 41 g/day, p = 0.001). PD patients who (1) experienced chronic pain, (2) were depressed, or (3) reported an impulse control disorder, consumed more total sugars than HCs (all p < 0.05). Increased sugar consumption was associated with an increase in non-motor symptoms, including poorer quality of life, increased constipation severity and greater daily levodopa dose requirement.

Conclusions: We provide clinically important insights into the dietary habits of PD patients that may inform simple dietary modifications that could alleviate disease symptoms and severity. The results of this study support clinician led promotion of healthy eating and careful management of patient nutrition as part of routine care.

Malnutrition and related factors in Filipino patients with Parkinson's disease: results from a pilot study

Aim: Emerging evidence demonstrates a bidirectional relationship between nutritional status and Parkinson's disease (PD). Our aim was to determine the local prevalence of malnutrition and associated factors among Filipino PD patients. Materials & methods: We assessed the nutritional status of 95 PD patients using the body mass index (BMI) and Subjective Global Assessment (SGA) and identified malnutrition-associated factors. Results & conclusion: In our sample, the mean BMI was 24.5 ± 4.2 kg/m². Consistent with published estimates, five (5.3%) patients were classified as underweight and 57 (60%) patients were classified as overweight/obese. A total of 30 (31.6%) patients had abnormal nutritional status based on SGA. Weight-adjusted levodopa equivalent daily dose was a significant factor (p = 0.032) for BMI, while dysphagia and higher weight-adjusted levodopa equivalent daily dose were found to be predictive of abnormal nutritional status using SGA (adjusted odds ratio of 8.85 [95% CI: 1.59-49.17; p = 0.015] and 1.10 [95% CI: 1.02-1.20; p = 0.021], respectively).

Nutritional status and activities of daily living in patients with Parkinson's disease

Patients with Parkinson's disease are often frail and likely to be malnourished. Several studies have reported the adverse effects of malnutrition on functional outcomes; however, the association between nutritional status and activities of daily living is unclear among patients with Parkinson's disease. This study aimed to investigate the relationship between nutritional status and activities of daily living in patients with Parkinson's disease. We conducted a retrospective cohort study with the data of 124 patients who were consecutively admitted to a rehabilitation hospital in Japan, among whom the data of 61 patients were included in the analyses. The Controlling Nutritional Status score was used to measure the nutritional status of the participants, and the motor subdomain of the Functional Independence Measure was used to assess the activities of daily living. Piecewise linear mixed-effects models were fitted to the data after adjusting for confounding factors. A poor nutritional status (i.e., Controlling Nutritional Status score >3) was significantly associated with a poor Functional Independence Measure gain, which was defined as difference in the score values of the Functional Independence Measures between discharge and admission. Our findings could aid in developing nutritional intervention programs for patients with Parkinson's disease by employing the Controlling Nutritional Status score to improve their activities of daily living.

Hypothalamic α-synuclein and its relation to autonomic symptoms and neuroendocrine abnormalities in Parkinson disease

Parkinson's disease (PD) is a complex neurodegenerative disorder presenting with defining motor features and a variable combination of nonmotor symptoms. There is growing evidence suggesting that hypothalamic involvement in PD may contribute to the pathogenesis of nonmotor symptoms. Initial neuropathologic studies demonstrated histologic involvement of hypothalamic nuclei by Lewy pathology, i.e., neuronal aggregates including Lewy bodies (round eosinophilic inclusions with a halo found in the neuronal perikarya) and other inclusions in neuronal processes such as Lewy neurites. Recent studies using more sensitive immunohistochemistry have shown that synuclein deposition is common in all hypothalamic nuclei and can happen at preclinical stages of the disease. Several neuropathologic changes, including synuclein deposition, neuronal loss, and adaptative morphologic changes, have been described in neurochemically defined specific hypothalamic cell populations with a potential role in the pathogenesis of nonmotor symptoms such as autonomic dysfunction, blood pressure control, circadian rhythms, sleep, and body weight regulation. The clinical implications of these hypothalamic neuropathologic changes are not fully understood and a direct clinical correlation may be challenging due to the multifactorial pathogenesis of the symptomatology and the additional involvement of other peripheral regulatory mechanisms. Future neuropathologic research using histological and functional assessments should establish the potential role of hypothalamic dysfunction on clinical burden, symptomatic therapies, and disease biomarkers in PD.

Leptin levels in patients with Parkinson's disease: A systematic review and meta-analysis

BACKGROUND AND AIMS

The exact mechanism of Parkinson's disease (PD) is not fully understood yet, but it is suggested that inflammation is one of its contributing factors. Among several inflammatory factors, adipokines, especially leptin may have a great role in this mechanism; since it is not only causing inflammation, but it can also play other roles in the body that may contribute to the symptoms described for PD. Regarding the contradictions in the association of serum leptin levels with Parkinson's disease, a systematic review and meta-analysis was performed to have a more accurate estimation of this relationship.

METHODS

Published literature was obtained by searching PubMed, Embase, Cochrane Library, Scopus, Ovid, ProQuest and Google Scholar. Random-effect model analysis was used to calculate pooled standard mean difference (SMD) with 95% confidence interval (CI). Heterogeneity was tested with the heterogeneity statistic Q and quantified using I². Newcastle-Ottawa scale was used to assess the study quality.

RESULTS

Six studies including a total number of 198 PD patients and 182 controls were finally included in the meta-analysis. Serum leptin levels in PD patients were non-significantly lower than those in control group (SMD = -0.40 ng/ml, 95% CI -2.33-1.53). Subgroup analyses revealed that serum leptin levels of PD patients and controls in either females or males didn't show any significant difference.

CONCLUSIONS

This meta-analysis revealed that leptin level doesn't show any significant difference between PD patients and healthy controls, even when taking the participants' gender into consideration.

Influence of Bilateral Subthalamic Nucleus Deep Brain Stimulation on the Lipid Profile in Patients With Parkinson's Disease

Background: Subthalamic nucleus deep brain stimulation (STN-DBS) is a valuable alternative to pharmacotherapy alone in an advanced Parkinson's disease (PD). Given the growing number of patients with STN-DBS, its impact on the comorbidities should be considered.

Aim: The aim of this study was to evaluate the influence of bilateral STN-DBS on the lipid profile in patients with PD.

Methods: Three groups of parkinsonian patients were included: 20 treated pharmacologically–PHT group, 20 newly qualified for STN-DBS–DBS group, and 14 postoperative patients (median 30 months after surgery)–POP group. Plasma concentrations of the total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and body weight were measured thrice in 9 ± 2 month intervals.

Results: A significant increase in the LDL-C concentration is observed early after surgery in the DBS group (11.4 mg/dl, P < 0.01) followed by adverse changes in the HDL-C (−7.7 mg/dl, P = 0.01) and TG (14.1 mg/dl, P = 0.05) plasma levels. In the POP group, the average level of TC at the first visit was significantly higher (P < 0.01) than in the other groups and the TG level was higher than in the PHT group during the follow-up (P < 0.01). A strong positive correlation with body weight alteration after surgery was observed only for long-term changes in the TG levels.

Conclusions: Our data indicate that STN-DBS may negatively affect the cardiometabolic profile of patients. Similarly to body weight gain, an increase in the LDL-C concentration occurred early after surgery while adverse changes in the HDL-C and TG plasma levels were more gradual.

Prevalence, risk factors, and clinical correlations of underweight in Chinese newly diagnosed and drug-naïve patients with Parkinson's disease

OBJECTIVE

Studies have shown that patients with Parkinson's disease (PD) will experience weight loss during the progression of the illness, which suggests an increased rate of underweight. However, few studies have addressed underweight in early de novo population. This study aimed to examine the prevalence, risk factors, and clinical correlations of underweight in Chinese newly diagnosed and drug-naïve patients with PD.

METHODS

A total of 245 inpatients with newly diagnosed PD and 213 age-, sex-, and education-matched healthy controls were enrolled in Ningbo. BMI, demographics, supine and upright blood pressure, Montreal Cognitive Assessment (MoCA), Hamilton Anxiety Scale (HAMA), Hamilton Depression Scale (HAMD) together with fasting blood glucose, low-density lipoprotein, total cholesterol, uric acid (UA), and homocysteine were collected in all subjects. Hoehn and Yahr (HY) rating and Unified Parkinson's Disease Rating Scale (UPDRS) motor scores were also measured in patients.

RESULTS

Overall, 35 (14.3%) patients were underweight and 14 (6.6%) controls were underweight. Binary regression analyses showed that low MoCA (p = 0.035), ΔSBP and ΔDBP values (both p < 0.001) were risk factors for underweight. Furthermore, correlation analysis indicated that BMI was associated with HY grade, UPDRS motor, HAMA, HAMD, MoCA, ΔSBP, ΔDBP, and UA values, stepwise multiple regression revealed significant correlations between BMI and ΔSBP (p < 0.001), ΔDBP (p = 0.001), MoCA (p = 0.002), UPDRS motor (p = 0.005), and HAMD scores (p = 0.014).

CONCLUSIONS

Our study showed that the prevalence of underweight was significantly higher in Chinese newly diagnosed and drug-naïve patients with PD than in the healthy population, and several clinical variables were risk factors for underweight.

Longitudinal association between dopamine agonists and weight in Parkinson's disease

OBJECTIVE

To examine the longitudinal relation of dopamine agonists (DA) use with body mass index (BMI) change and weight gain in Parkinson's disease (PD).

METHODS

In a cohort of 356 patients with PD annually followed up to 6 years, BMI, antiparkinsonian drugs use, and impulse control disorders (ICDs) were assessed at each visit. DA dose trajectories were estimated using latent class mixed models. The association of DA use with BMI change and weight gain was examined using latent-process mixed models and time-dependent Cox models respectively, while adjusting for disease severity and levodopa (LD) use.

RESULTS

In the mixed model, BMI (kg/m²) increased over the follow-up in DA users (beta_DA×time = 0.13, 95% CI = 0.02, 0.24) compared to non-users, while it decreased in LD users (beta_LD×time = -0.26, 95% CI = -0.38, -0.13). We identified three trajectories of average daily DA dose over the follow-up. Patients in the high trajectory gained more weight than patients who never used DA (P = .001) and in the low (P = .02) or moderate (P = .04) trajectories. The incidence of weight gain of ≥6 kg was 2.10-fold (95% CI = 1.03, 4.28) higher in DA users compared to non-users, while LD users were less likely to gain weight (HR = 0.60, 95% CI = 0.33, 1.11). Associations decreased in analyses adjusted for compulsive eating or ICDs.

CONCLUSION

Weight increased in DA users over 6 years, and DA use was associated with increased incidence of weight gain. These associations were partially explained by compulsive eating. Alternatively, weight decreased in LD users. These findings warrant careful monitoring of compulsive eating and weight in PD patients.

Emerging Concepts of Motor Reserve in Parkinson's Disease

The concept of cognitive reserve (CR) in Alzheimer's disease (AD) explains the differences between individuals in their susceptibility to AD-related pathologies. An enhanced CR may lead to less cognitive deficits despite severe pathological lesions. Parkinson's disease (PD) is also a common neurodegenerative disease and is mainly characterized by motor dysfunction related to striatal dopaminergic depletion. The degree of motor deficits in PD is closely correlated to the degree of dopamine depletion; however, significant individual variations still exist. Therefore, we hypothesized that the presence of motor reserve (MR) in PD explains the individual differences in motor deficits despite similar levels of striatal dopamine depletion. Since 2015, we have performed a series of studies investigating MR in de novo patients with PD using the data of initial clinical presentation and dopamine transporter PET scan. In this review, we summarized the results of these published studies. In particular, some premorbid experiences (i.e., physical activity and education) and modifiable factors (i.e., body mass index and white matter hyperintensity on brain image studies) could modulate an individual's capacity to tolerate PD pathology, which can be maintained throughout disease progression.

Progressive and accelerated weight and body fat loss in Parkinson's disease: A three-year prospective longitudinal study

INTRODUCTION

Although weight loss is common in Parkinson's disease (PD), longitudinal studies assessing weight and body composition changes are limited.

METHODS

In this three-year longitudinal study, 125 subjects (77 PD patients and 48 spousal/sibling controls) underwent clinical, biochemical and body composition assessments using dual-energy X-ray absorptiometry.

RESULTS

Patients were older than controls (65.6 ± 8.9 vs. 62.6 ± 7.1, P = 0.049), with no significant differences in gender, comorbidities, dietary intake and physical activity. Clinically significant weight loss (≥5% from baseline weight) was recorded in 41.6% of patients, with a doubling of cases (6.5 to 13.0%) classified as underweight at study end. Over three years, patients demonstrated greater reductions in BMI (mean -1.2 kg/m², 95%CI-2.0 to -0.4), whole-body fat percentage (-2.5% points, 95%CI-3.9 to -1.0), fat mass index (FMI) (-0.9 kg/m², 95%CI-1.4 to -0.4), visceral fat mass (-0.1 kg, 95%CI-0.2 to 0.0), and subcutaneous fat mass (-1.9 kg, 95%CI-3.4 to -0.5) than in controls, with significant group-by-time interactions after adjusting for age and gender. Notably, 31.2% and 53.3% of patients had FMI<3rd (severe fat deficit) and <10th centiles, respectively. Muscle mass indices decreased over time in both groups, without significant group-by-time interactions. Multiple linear regression models showed that loss of body weight and fat mass in patients were associated with age, dyskinesia, psychosis and constipation.

CONCLUSIONS

We found progressive loss of weight in PD patients, with greater loss of both visceral and subcutaneous fat, but not muscle, compared to controls. Several associated factors (motor and non-motor disease features) were identified for these changes, providing insights on possible mechanisms and therapeutic targets.

The association between freezing of gait, fear of falling and anxiety in Parkinson's disease: a longitudinal analysis

Aim: We studied the longitudinal associations between freezing of gait (FoG), fear of falling (FoF) and anxiety, and how these associations are influenced by confounding factors. Materials & methods: We analyzed longitudinal motor and nonmotor measurements from 153 Parkinson's disease patients. Possible confounding factors were divided into three subgroups: demographics, disease characteristics, medication use and adverse effects of medication. Results: All crude associations between FoG, FoF and anxiety were significant and remained so after adjusting for confounders. When analyzing FoF and anxiety together as independent variables, the association between FoG and FoF remained, and the association between FoG and anxiety diminished. Conclusion: We confirm the complex interactions between motor and nonmotor symptoms in Parkinson's disease, and plead for a multidisciplinary approach.

Altered Body Composition and Increased Resting Metabolic Rate Associated with the Postural Instability/Gait Difficulty Parkinson's Disease Subtype

Background

Weight loss in Parkinson's disease (PD) patients is a common but poorly understood manifestation. Several studies have reported that weight changes could be related to motor symptoms, drug side effects, dysphagia, depression, and/or dementia. Weight loss in PD is not a benign phenomenon and it has several clinical and prognostic implications with increased morbidity and mortality. Thus, it is crucial to determine nutritional changes in PD patients in order to prevent malnutrition and improve their quality of life.

Objective

To compare body composition and resting metabolic rates between PD patients and controls.

Methods

A total of 64 PD patients and 52 controls were studied. The Hoehn-Yahr scale was used to determine the disease stage, clinical and epidemiological data were recorded from verbal questionnaire, Inbody S10® was used to collect corporal parameters, and FitMate system was used to assess the resting metabolic rate.

Results

No significant differences were found between both experimental groups in age, gender, height, cholesterol levels, and the presence of hypertension, diabetes, and hypo/hyperthyroidism. However, the PD group showed lower body fat mass, whole-body fat percentage, and greater resting metabolic rate compared to controls (p < 0.05), with no significant differences in musculoskeletal mass. Parkinson's disease postural instability/gait difficulty (PD-PIGD) subtype showed lower body fat parameters, increased fat-free mass, and higher resting metabolic rates.

Conclusions

These results suggest that PD patients present an increased resting metabolic rate associated with the postural instability/gait difficulty PD subtype, allowing a selective decrease of body fat mass and not musculoskeletal mass. Of note, several disease-related factors may contribute to this weight loss in PD patients, being a complex and multifactorial consequence. Our findings could likely be one of the many contributing factors. However, present findings may further add to our understanding of the phenomenon of weight loss in patients with PD.

Resting energy expenditure in Parkinson's disease patients under dopaminergic treatment

Background: Weight homeostasis is complex in Parkinson's disease (PD) and body weight changes substantially throughout the course of the disease. We designed a case-control study to (i) investigate whether PD is associated with changes in resting energy expenditure (REE), (ii) to assess how accurately REE could be predicted for individuals with PD utilizing the equations constructed for healthy individuals, and (iii) to eventually construct a new equation.Materials & Methods: Measured REE (mREE) was compared between 122 PD patients and 122 gender and body mass index (BMI)-matched controls. The accuracy of estimated REE by 5 common equations (Harris/Benedict-1919, Roza/Shizgal-1984, Mifflin St. Jeor, WHO/FAO and aggregate formula) was investigated in PD using Bland-Altman analysis and reported as the frequency of accurate predictions (±10%). Concordance correlation coefficients (CCC) were also calculated. Then, we regressed a new REE equation - using gender, age, weight, height and Hoehn-Yahr stage - and validated it in an independent sample (N = 100).Results: No significant difference in mREE was recorded between the whole PD sample and healthy controls. However, mREE was increased in patients with BMI ≥ 30 kg/m² and Hoehn-Yahr stage ≥ 3. Limited accuracy was present in the available REE equations (accurate prediction [±10%] frequency, <60% for all). For the new equation, the proportion of accurate prediction was 67.0% (overestimation, 24.0%) and CCC was 0.77.Conclusion: PD patients are not commonly characterized by an increase in REE. This is limited to patients suffering from obesity and more severe disease. Common REE equations appear to be inaccurate. The new predictive equation proposed in this study provided better REE estimates.