Increased risk of Parkinson's disease in cataract patients: A population-based cohort study

Exploring ocular disorders in Parkinson's disease: A comprehensive review and future perspectives

Parkinson's disease (PD) is a multifaceted neurodegenerative disorder characterized by predominantly motor symptoms. However, recent research has broadened our understanding of PD by revealing its impact on non-motor functions, including ocular manifestations. This review explored the intricate relationship between PD and ocular health, shedding light on the mechanisms underlying common ocular diseases such as dry eye disease, cataract, glaucoma, age-related macular degeneration, and diabetic retinopathy. It also underscores the importance of recognizing ocular manifestations as potential early markers of PD, as well as their impact on patients' daily activities, necessitating prompt identification and intervention to prevent complications and enhance the overall quality of life. Furthermore, future research should prioritize unraveling the potential association between PD and other prevalent ocular diseases, such as myopia, to formulate effective treatment strategies.

Cataract surgery utilization in Parkinson's disease: the english longitudinal survey on ageing

PURPOSE

Older adults with Alzheimer's disease are less likely to be offered cataract surgery than the general population, but these disparities have not been examined in the context of other neurodegenerative disorders such as Parkinson's disease (PD).

METHODS

Using data from the English Longitudinal Study on Ageing (ELSA), an ongoing, longitudinal population-based survey of older adults in England, we examined the relationship between PD and cataract surgery among adults 50 and older. We used logistic regression to measure the association between PD and history of cataract surgery at baseline. In longitudinal analyses of subjects with no history of cataract surgery at time of enrollment, we used semiparametric, discrete-time proportional hazards models to model the incidence of cataract surgery as a function of PD and other time-dependent covariates. Models were adjusted for demographic variables, self-reported comorbidities, and measures of daily activity limitation.

RESULTS

We included data from 19,241 eligible ELSA respondents, of whom 231 (1.2%) reported a diagnosis of PD. PD was positively associated with a history of self-reported cataract surgery at baseline (OR 3.66, 95% CI: 2.55-5.26), but this did not remain significant after adjusting for confounders (OR 1.22, 95% CI: 0.75-1.98). Among subjects with no history of cataract surgery at baseline, PD was also not associated with incident cataract surgery (adjusted HR 1.32, 95% CI: 0.86-2.02).

CONCLUSION

Unlike Alzheimer's disease, people with PD were no less likely to receive cataract surgery compared to those without PD.

Association of time spent outdoors with the risk of Parkinson's disease: a prospective cohort study of 329,359 participants

BACKGROUND

Studies on the association between time spent outdoors and the development of Parkinson's disease (PD) are lacking, and whether this relationship differs in different subgroups (age, sex) remains unclear.

OBJECTIVE

We here examined the association between time spent outdoors and the incidence of PD in different seasons.

METHODS

This study included 329,359 participants from the UK Biobank. Data regarding hours spent outdoors during a typical day were obtained through questionnaires. Cox proportional hazard regression models were used to estimate hazard ratios (HRs) for the association between exposure to outdoors duration and PD incidence. Restricted cubic spline was used to explore the potential nonlinear relationship between time spent outdoors and PD risk. To explore the potential mechanisms of time spent outdoors effecting the risk of PD incidence, their association with serum vitamin D was further analysed separately.

RESULTS

During a median follow-up of 13.57 years, 2,238 participants developed PD. In summer, time spent outdoors > 5.0 h/day was associated with a reduced PD risk compared with ≤ 2.0 h/day (HR = 0.84, 95% CI, 0.74-0.95). In winter too, time spent outdoors > 2.0 h/day was also associated with a reduced PD risk compared with ≤ 1.0 h/day (HR = 0.85, 95% CI, 0.76-0.94). For annual average time spent outdoors, participants who went outdoors for more than 3.5 h/day had a reduced PD risk than those who went outdoors for ≤ 1.5 h/day (HR = 0.85, 95% CI, 0.75-0.96). Additionally, sex and age differences were observed in the association between time spent outdoors and the PD risk. Moreover, Time spent outdoors was observed to be positively associated with serum vitamin D levels. Compared with serum vitamin D-deficient participants, the risk of PD was reduced by 15% in the sufficient participants.

CONCLUSION

In the total population, higher time spent outdoors was linked to a reduced PD risk. However, this association may vary among different age or sex groups.

Association between Low Blood Pressure and Subsequent Risk of Parkinson's Disease in Older Adults Aged ≥75 Years

INTRODUCTION

The association between blood pressure (BP) and incidence of Parkinson's disease (PD) in older adults remains uncertain. Therefore, this study aimed to investigate the association between BP (high or low) and PD incidence in adults aged ≥75 years.

METHODS

In this nationwide population-based cohort study, we enrolled participants aged ≥75 years without a prior PD diagnosis who had undergone health examination provided by the Korean National Health Insurance Service at least once from January 1, 2009, to December 31, 2012. The participants were followed up until December 31, 2019, or the date of their death. The Cox proportional hazards model was used to assess the risk of PD depending on systolic BP (SBP), diastolic BP (DBP), and pulse pressure.

RESULTS

Overall, 963,525 participants were enrolled in the analysis and followed up until December 31, 2019, or the date of death (40.7% male, mean age 78.5 ± 3.6 years). The mean SBP and DBP were 131.4 ± 16.7 and 77.9 ± 10.3 mm Hg, respectively. During the 10-year follow-up period, 16,414 (1.7%) newly diagnosed cases of PD were reported. A significant inverse dose-response association was found between SBP and PD incidence. In the subgroup analysis, this association was maintained for most variables, including sex, use of antihypertensive medication, comorbidities, alcohol consumption, physical activity, and body mass index, except for smoking status.

CONCLUSION

Lower SBP and DBP were associated with a higher PD incidence in older adults. These results may have substantial implications for determining the optimal BP control target in adults aged ≥75 years.

The central role of the NLRP3 inflammasome pathway in the pathogenesis of age-related diseases in the eye and the brain

With increasing age, structural changes occur in the eye and brain. Neuronal death, inflammation, vascular disruption, and microglial activation are among many of the pathological changes that can occur during ageing. Furthermore, ageing individuals are at increased risk of developing neurodegenerative diseases in these organs, including Alzheimer's disease (AD), Parkinson's disease (PD), glaucoma and age-related macular degeneration (AMD). Although these diseases pose a significant global public health burden, current treatment options focus on slowing disease progression and symptomatic control rather than targeting underlying causes. Interestingly, recent investigations have proposed an analogous aetiology between age-related diseases in the eye and brain, where a process of chronic low-grade inflammation is implicated. Studies have suggested that patients with AD or PD are also associated with an increased risk of AMD, glaucoma, and cataracts. Moreover, pathognomonic amyloid-β and α-synuclein aggregates, which accumulate in AD and PD, respectively, can be found in ocular parenchyma. In terms of a common molecular pathway that underpins these diseases, the nucleotide-binding domain, leucine-rich-containing family, and pyrin domain-containing-3 (NLRP3) inflammasome is thought to play a vital role in the manifestation of all these diseases. This review summarises the current evidence regarding cellular and molecular changes in the brain and eye with age, similarities between ocular and cerebral age-related diseases, and the role of the NLRP3 inflammasome as a critical mediator of disease propagation in the eye and the brain during ageing.

Anesthetic Considerations for Cataract Surgery in Patients with Parkinson's Disease: A Narrative Review

Parkinson's disease (PD) is a chronic neurological degenerative disease affecting the central nervous system, which is responsible for progressive disorders such as slow movements, tremors, rigidity, and cognitive disorders. There are no specific recommendations and guidelines for anesthetic management of patients with PD undergoing ophthalmic procedures. This narrative review aims to summarise the anesthetic considerations in patients with PD presenting for cataract surgery.

Narrative Review Concerning the Clinical Spectrum of Ophthalmological Impairments in Parkinson's Disease

Ophthalmic non-motor impairments are common in Parkinson's disease patients, from the onset of the neurodegenerative disease and even prior to the development of motor symptoms. This is a very crucial component of the potential for early detection of this disease, even in its earliest stages. Since the ophthalmological disease is extensive and impacts all extraocular and intraocular components of the optical analyzer, a competent assessment of it would be beneficial for the patients. Because the retina is an extension of the nervous system and has the same embryonic genesis as the central nervous system, it is helpful to investigate the retinal changes in Parkinson's disease in order to hypothesize insights that may also be applicable to the brain. As a consequence, the detection of these symptoms and signs may improve the medical evaluation of PD and predict the illness' prognosis. Another valuable aspect of this pathology is the fact that the ophthalmological damage contributes significantly to the decrease in the quality of life of patients with Parkinson's disease. We provide an overview of the most significant ophthalmologic impairments associated with Parkinson's disease. These results certainly constitute a large number of the prevalent visual impairments experienced by PD patients.

Incidence of cataract surgeries in relation to diagnosis of Parkinson's disease

BACKGROUND

Parkinson's disease (PD) causes also visual dysfunction including decreased visual acuity, even already at the prodromal phase of disease. Still, it has been suggested that persons with PD may be less likely to be referred for cataract surgery, although early management increases the chances for successful cataract surgery.

METHODS

Data from nationwide register-based Finnish Study on Parkinson's Disease (N=22189) was used. This study included 17546 persons with PD diagnosed in 1996-2015 and 114817 comparison persons who were at least 45 years old. Comparison persons were matched for age (+/-1 year, sex and hospital district on the date of PD diagnosis (index date). Incidence of cataract surgeries was investigated from ten years before to ten years after the index date. Information on cataract surgeries and comorbidities were extracted from several nationwide healthcare registers.

RESULTS

The incidence rate of cataract surgeries was 20.4/1000 and 18.7/1000 person-years (PY) for persons with or without PD, respectively. Before PD diagnosis, rate of surgeries was higher in persons with PD (incidence rate 16.5 vs 13.7 /1000PY, IRR, 95%CI 1.21, 1.16-1.26). After PD diagnosis there was no difference in the incidence rate. Persons who had undergone cataract surgery were older and had more eye diseases and other comorbidities compared to those without surgery.

CONCLUSIONS

Diagnosis of PD does not decrease the incidence of cataract surgeries. Conversely, the incidence may be increased prior to PD diagnosis, probably due to other eye diseases and prodromal symptoms of PD.

Advances in ophthalmic drug delivery technology for postoperative management after cataract surgery

INTRODUCTION

Cataract surgery is becoming more common due to an aging world population. Intraocular lenses and surgical technique have developed remarkably recently, but the development of postoperative medication to prevent postsurgery complications has been relatively delayed. We still largely depend on eye drops for the management of post-cataract-surgery patients. Mental and physical problems that often occur in elderly cataract patients make it difficult for patients to apply eye drops by themselves. It is necessary to develop new effective drug delivery methods.

AREAS COVERED

This updated review article provides a brief review of why drug management is needed following cataract surgery and an overview of current developments in new drug delivery methods for ophthalmic treatment. In particular, various novel drug delivery methods that can be used for post-cataract-surgery management and their current development stages are extensively reviewed.

EXPERT OPINION

Rapidly developing technologies, such as intraocular and external ophthalmic implants, polymers, and nanotechnology, are being actively applied to develop novel drug delivery systems for safe and effective management after cataract surgery. Their goal is to achieve sufficient drug release for the desired duration with a single application. These will largely replace the inconvenience of eye drops for elderly patients in the future.

Parkinson’s Disease Etiology: Insights and Associations with Phosphate Toxicity

The present paper investigated the association of Parkinson’s disease etiology with phosphate toxicity, a pathophysiological condition in which dysregulated phosphate metabolism causes excessive inorganic phosphate sequestration in body tissue that damages organ systems. Excessive phosphate is proposed to reduce Complex I function of the mitochondrial electron transport chain in Parkinson’s disease and is linked to opening of the mitochondrial permeability transition pore, resulting in increased reactive oxygen species, inflammation, DNA damage, mitochondrial membrane depolarization, and ATP depletion causing cell death. Parkinson’s disease is associated with α-synuclein and Lewy body dementia, a secondary tauopathy related to hyperphosphorylation of tau protein, and tauopathy is among several pathophysiological pathways shared between Parkinson’s disease and diabetes. Excessive phosphate is also associated with ectopic calcification, bone mineral disorders, and low levels of serum vitamin D in patients with Parkinson’s disease. Sarcopenia and cancer in Parkinson’s disease patients are also associated with phosphate toxicity. Additionally, Parkinson’s disease benefits are related to low dietary phosphate intake. More studies are needed to investigate the potential mediating role of phosphate toxicity in the etiology of Parkinson’s disease.

Retinal Degeneration: A Window to Understand the Origin and Progression of Parkinson’s Disease?

Parkinson’s disease (PD), the second most prevalent neurodegenerative disorder, manifests with motor and non-motor symptoms associated with two main pathological hallmarks, including the deterioration of dopaminergic cells and aggregation of alpha-synuclein. Yet, PD is a neurodegenerative process whose origin is uncertain and progression difficult to monitor and predict. Currently, a possibility is that PD may be secondary to long lasting peripheral affectations. In this regard, it has been shown that retinal degeneration is present in PD patients. Although it is unknown if retinal degeneration precedes PD motor symptoms, the possibility exists since degeneration of peripheral organs (e.g., olfaction, gut) have already been proven to antedate PD motor symptoms. In this paper, we explore this possibility by introducing the anatomical and functional relationship of retina and brain and providing an overview of the physiopathological changes of retinal structure and visual function in PD. On the basis of the current status of visual deficits in individuals with PD, we discuss the modalities and pathological mechanism of visual function or morphological changes in the retina and focus on the correlation between visual impairment and some representative structural features with clinical significance. To consider retinal degeneration as a contributor to PD origin and progress is important because PD evolution may be monitored and predicted by retinal studies through state-of-the-art techniques of the retina. It is significant to integrally understand the role of retinal morphological and functional changes in the neurodegenerative process for the diagnosis and therapeutic strategies of PD.

Case-control study of hypertension and Parkinson's disease

We evaluate the association of hypertension with PD in an Asian population and performed a meta-analysis on similar studies to address the effect of hypertension on PD risk. A matched case-control study involving 1342 Chinese subjects (671 PD and 671 age and gender-matched controls (with a mean age of 63.9 ± 9.7 and 63.5 ± 9.8 years, and identical proportion of gender distribution) was conducted. Hypertension increases PD risk by 1.9 times [OR 1.86 (1.46–2.38)]. The literature search identified 618 studies initially; however, only three matched case-control studies (all in Caucasians) met the inclusion criteria for meta-analysis. Overall analysis showed that hypertension decreases PD risk by 0.2 times [OR 0.80 (0.66–0.96)]. Hypertension increases PD risk by 1.9 times in our Asian population. However, a meta-analysis comprising of Caucasian populations showed a protective effect of hypertension suggesting that ethnic differences or other genetic or environmental factors may contribute to the divergent observation. Early diagnosis and treatment of hypertension may potentially reduce the risk of PD, at least in our population.

Applicability of optical coherence tomography angiography (OCTA) imaging in Parkinson's disease

To evaluate the significance of motion artifacts in optical coherence tomography angiography (OCTA) images of patients with Parkinson’s disease (PD) and healthy controls. In this prospective, cross-sectional study subjects with medicated PD (ON) and healthy, age- and gender-matched volunteers were recruited. Participants underwent specific ophthalmological examinations, including OCTA. Angiograms of the superficial retinal capillary plexus were evaluated for the type and frequency of artifacts using a validated motion artifact score (MAS). A total of 30 PD patients (60 eyes), average disease duration of 9.61 ± 5.55 years, and 30 matched, healthy controls (60 eyes) were recruited. Twenty percent of all eyes had an eye disease, unknown to the participant, with a significant impact on OCTA results. After cleansing the dataset by excluding subjects with confounding ocular comorbidities 42 eyes of 28 PD patients and 53 eyes of 29 healthy controls were further evaluated. Overall MAS and all five subtypes of motion artifacts were comparable without significant differences between groups. OCTA can be used in treated PD patients (ON) without a significant increase in motion artifacts. Nevertheless, special attention should be paid to image quality during the acquisition of OCTA data, for which an experienced OCTA operator is useful.

Molecular Mechanisms and Clinical Manifestations of Catecholamine Dysfunction in the Eye in Parkinson's Disease As a Basis for Developing Early Diagnosis

This review provides information on the non-motor peripheral manifestations of Parkinson's disease (PD) associated with a pathology of the visual analyzer and the auxiliary apparatus of the eye. The relationship between neurodegenerative processes that take place in the brain and in the eye opens new prospects to use preventive ophthalmologic examination to diagnose PD long before the characteristic motor symptoms appear. This will encourage the use of neuroprotective therapy, which stops, or at least slows down, neuronal death, instead of the current replacement therapy with dopamine agonists. An important result of an eye examination of patients with PD may be a non-invasive identification of new peripheral biomarkers manifesting themselves as changes in the composition of the lacrimal fluid.

Falls in Synucleinopathies

Parkinson's disease (PD) and other synucleinopathies, namely dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), are common degenerative neurological disorders that share synuclein pathology. Although certain cardinal features of parkinsonism, including bradykinesia and rigidity, respond well to levodopa, axial features, such as gait and balance impairment, are less reliably responsive to dopaminergic therapy and surgical interventions. Consequently, falls are common in PD and other synucleinopathies and are a major contributor toward injury and loss of independence. This underscores the need for appropriate fall risk assessment and implementation of preventative measures in all patients with parkinsonism. The aim of this review is therefore to explore modifiable and non-modifiable risk factors for falls in synucleinopathies. We next review and evaluate the evidence for pharmacological, nonpharmacological, and surgical approaches for fall prevention, and emphasize individualized and multifaceted approaches.

Association between allopurinol use and Parkinson's disease in older adults

INTRODUCTION

Little evidence is available about the association between allopurinol use and Parkinson's disease. The present study aimed to explore the association between allopurinol use and Parkinson's disease in older adults in Taiwan.

METHODS

We conducted a population-based case-control study using the database of the Taiwan National Health Insurance Program. In total, 4399 subjects aged ≥ 65 years with newly diagnosed Parkinson's disease between 2000 and 2013 were included as the cases. Additionally, 4399 subjects aged ≥ 65 years without Parkinson's disease were randomly selected as the controls. Both cases and controls were matched for age and comorbidities. Ever use of allopurinol was defined as subjects who had at least a prescription for allopurinol before the index date, whereas never use of allopurinol was defined as those who never had a prescription for allopurinol before the index date. We used the logistic regression model to calculate the odds ratio (OR) and 95% confidence interval (CI) for the association between allopurinol use and Parkinson's disease.

RESULTS

The OR of Parkinson's disease was 0.93 for subjects with ever use of allopurinol (95% CI 0.82, 1.04), compared with never use.

CONCLUSIONS

No association can be detected between allopurinol use and Parkinson's disease in older adults in Taiwan.

Towards an Integrative Understanding of tRNA Aminoacylation-Diet-Host-Gut Microbiome Interactions in Neurodegeneration

Transgenic mice used for Alzheimer’s disease (AD) preclinical experiments do not recapitulate the human disease. In our models, the dietary tryptophan metabolite tryptamine produced by human gut microbiome induces tryptophanyl-tRNA synthetase (TrpRS) deficiency with consequent neurodegeneration in cells and mice. Dietary supplements, antibiotics and certain drugs increase tryptamine content in vivo. TrpRS catalyzes tryptophan attachment to tRNA^trp at initial step of protein biosynthesis. Tryptamine that easily crosses the blood–brain barrier induces vasculopathies, neurodegeneration and cell death via TrpRS competitive inhibition. TrpRS inhibitor tryptophanol produced by gut microbiome also induces neurodegeneration. TrpRS inhibition by tryptamine and its metabolites preventing tryptophan incorporation into proteins lead to protein biosynthesis impairment. Tryptophan, a least amino acid in food and proteins that cannot be synthesized by humans competes with frequent amino acids for the transport from blood to brain. Tryptophan is a vulnerable amino acid, which can be easily lost to protein biosynthesis. Some proteins marking neurodegenerative pathology, such as tau lack tryptophan. TrpRS exists in cytoplasmic (WARS) and mitochondrial (WARS2) forms. Pathogenic gene variants of both forms cause TrpRS deficiency with consequent intellectual and motor disabilities in humans. The diminished tryptophan-dependent protein biosynthesis in AD patients is a proof of our model-based disease concept.

Hypertension and Diagnosis of Parkinson's Disease: A Meta-Analysis of Cohort Studies

Background

Hypertension has been associated with cognitive dysfunction in the general population and patients with Alzheimer's disease (AD). However, there are contradictory data regarding the potential association between hypertension and diagnosis of Parkinson's disease (PD), the second most common neurodegenerative disorder after AD. The purpose of this meta-analysis is to synthesize data from cohort studies to explore the potential association between preexisting hypertension and subsequent PD diagnosis.

Methods

The PubMed and Embase databases were searched to identify all relevant studies. Two independent investigators performed the data extraction. Eligible cohort studies providing risk and precision estimates related to hypertension and PD were selected. Pooled risk ratios (RRs) with 95% confidence interval (CI) were calculated by using a random-effects model or a fixed-effects model. Sensitivity analyses after excluding one study at a time were performed to assess the stability of the results. Publication bias was assessed with Begg's test and Egger's test.

Results

Seven cohort studies were identified, including 3,170 persons who were confirmed to have developed PD and 339,517 participants who did not have PD during follow-up. The onset of hypertension before PD diagnosis was significantly associated with an increased risk of motor stage PD (RR = 1.799, 95% CI [1.066-3.037]). This relationship was further confirmed by secondary analyses based on estimates adjusted for potential vascular confounders (RR = 1.319, 95% CI [1.073-1.622]). After excluding one study at a time, the sensitivity analyses still showed that hypertension history was significantly associated with an increased risk of motor stage PD (RR with 95% CI ranging from 1.11 [1.075-1.35] to 1.42 [1.65-1.83]). No publication bias was observed in this meta-analysis.

Conclusion

The findings of this meta-analysis suggest that hypertension may be a risk factor for motor stage PD, which may provide novel insights into the etiology and pathogenesis of this neurodegenerative disorder. However, large-scale well-designed studies that consider various confounders are still needed to further verify and clarify the association between hypertension and PD diagnosis.

Identification of key genes and pathways in Parkinson's disease through integrated analysis

Parkinson's disease (PD) is a progressive, degene-rative neurological disease, typically characterized by tremors and muscle rigidity. The present study aimed to identify differe-ntially expressed genes (DEGs) between patients with PD and healthy patients, and clarify their association with additional biological processes that may regulate factors that lead to PD. An integrated analysis of publicly available Gene Expression Omnibus datasets of PD was performed. DEGs were identified between PD and normal blood samples. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses, as well as protein‑protein interaction (PPI) networks were used to predict the functions of identified DEGs. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to validate the predicted expression levels of identified DEGs in whole blood samples obtained from patients with PD and normal healthy controls. A total of 292DEGs were identified between the PD and normal blood samples. Of these, 156 genes were significantly upregulated and 136 genes were significantly downregulated in PD samples following integrated analysis of four PD expression datasets. The 10 most upregulated and downregulated genes were used to construct a PPI network, where ubiquitin C‑terminal hydrolase L1 (UCHL1), 3‑phosphoinositide dependent protein kinase 1 (PDPK1) and protein kinase cAMP‑activated catalytic subunit β (PRKACB) demonstrated the highest connectivity in the network. DEGs were significantly enriched in amoebiasis, vascular smooth muscle contraction, and the Wnt and calcium signaling pathways. The expression levels of significant DEGs, UCHL1, PDPK1 and PRKACB were validated using RT‑qPCR analysis. The findings revealed that UCHL1 and PDPK1 were upregulated and PRKACB was downregulated in patients with PD when compared with normal healthy controls. In conclusion, the results indicate that the significant DEGs, including UCHL1, PDPK1 and PRKACB may be associated with the development of PD. In addition, these factors may be involved in various signaling pathways, including amoebiasis, vascular smooth muscle contraction and the Wnt and calcium signaling pathways.

Tamoxifen usage correlates with increased risk of Parkinson's disease in older women with breast cancer: a case-control study in Taiwan

BACKGROUND AND OBJECTIVES

Little is known about the association between tamoxifen usage and risk of Parkinson's disease in women with breast cancer. The present study aimed to evaluate the association between tamoxifen usage and Parkinson's disease in older women with breast cancer in Taiwan.

METHODS

We conducted a retrospective nationwide case-control study using the database of the Taiwan National Health Insurance Program. In total, 293 female subjects with breast cancer, aged 65 years and above, who were newly diagnosed with Parkinson's disease between 2000 and 2011 were included. Additionally, 1053 female subjects with breast cancer aged 65 years and above without Parkinson's disease were randomly selected as controls. Both cases and controls were matched for age and comorbidities. Ever use of tamoxifen was defined as subjects who had at least a prescription for tamoxifen before the index date, whereas never use of tamoxifen was defined as those who never had a prescription for tamoxifen before the index date. We used the unconditional logistic regression model to calculate the odds ratio (OR) and 95% confidence interval (CI) for the association between tamoxifen usage and risk of Parkinson's disease.

RESULTS

After adjusting for confounding variables, the adjusted OR of Parkinson's disease was 3.32 for subjects with ever use of tamoxifen (95% CI, 2.50-4.43), compared with nonusers. Further analysis showed that the adjusted ORs of Parkinson's disease were 3.21 (95% CI, 2.29-4.49), 3.95 (95% CI, 2.77-5.64), and 11.4 (95% CI, 2.63-49.7) for subjects with < 2, 2-6, and ≥ 6 years of cumulative tamoxifen usage, respectively, when compared with nonusers.

CONCLUSIONS

Tamoxifen usage was associated with a 3.32-fold increase in the likelihood of having Parkinson's disease among older women with breast cancer in Taiwan.

Use of Oral Corticosteroids and Risk of Hip Fracture in the Elderly in a Case-Control Study

Aim: Little is known regarding the relationship between use of oral corticosteroids and hip fracture in the elderly in Taiwan. The aim of the study was to examine this issue.

Methods: A retrospective population-based case-control study using the database of the Taiwan National Health Insurance Program (2000–2013) was conducted. We identified 4538 individuals aged ≥ 65 years with newly diagnosed hip fracture as the cases. We randomly selected 4538 individuals without hip fracture as the control subjects. The cases and the control subjects were matched with sex, age, comorbidities, and the year of index date. Individuals who never had a prescription for oral corticosteroids were defined as never use. Individuals who ever had at least one prescription for oral corticosteroids were defined as ever use. The odds ratio (OR) and 95% confidence interval (CI) of hip fracture associated with oral corticosteroids use was estimated by a multivariable unconditional logistic regression analysis.

Results: After adjustments for potential confounding factors, the multivariable logistic regression model showed that the adjusted OR of hip fracture was 1.17 for individuals with ever use of oral corticosteroids (95%CI 1.08, 1.28), compared to those with never use of oral corticosteroids. An sub-analysis showed that for every 1-mg increase in cumulative dose of oral corticosteroids, the adjusted OR of hip fracture was 1.01 (95% CI 1.01, 1.02). The adjusted ORs were 1.31 (95% CI 1.17, 1.47) for cumulative exposure to oral corticosteroids ≥ 3 months and 1.09 (95% CI 0.98, 1.20) for cumulative exposure < 3 months.

Conclusion: We conclude that oral corticosteroids use is associated with a trivial but statistically significant increase in risk of hip fracture in Taiwan. Additionally, the results suggest that there are dose-response and duration-response effects of oral corticosteroids on the risk of hip fracture. The results confirm our understanding of oral corticosteroid-associated hip fracture in the elderly.

Glaucoma correlates with increased risk of Parkinson's disease in the elderly: a national-based cohort study in Taiwan

BACKGROUND/OBJECTIVE

Very little is known about the association between glaucoma and Parkinson's disease in the elderly. The objective of this study was to determine whether glaucoma is associated with Parkinson's disease in older people in Taiwan.

METHODS

A retrospective cohort study was conducted to analyze the Taiwan National Health Insurance Program database from 2000 to 2010. We included 4330 subjects aged 65 years or older with newly diagnosed glaucoma as the glaucoma group, and 17,000 randomly selected subjects without a glaucoma diagnosis as the non-glaucoma group. Both groups were matched for sex, age, other comorbidities, and index year of glaucoma diagnosis. The incidence of Parkinson's disease at the end of 2011 was measured. A multivariable Cox proportional hazard regression model was used to measure the hazard ratio and 95% confidence intervals for Parkinson's disease associated with glaucoma.

RESULTS

The overall incidence of Parkinson's disease was 1.28-fold higher in the glaucoma group than that in the non-glaucoma group (7.73 vs. 6.02 per 1000 person-years; 95% confidence interval 1.18, 1.40). After controlling for potential confounding factors, the adjusted hazard ratio of Parkinson's disease was 1.23 for the glaucoma group (95% confidence interval 1.05, 1.46), compared with the non-glaucoma group.

CONCLUSIONS

Older people with glaucoma correlate with a small but statistically significant increase in the risk for Parkinson's disease. Whether glaucoma may be a non-motor feature of Parkinson's disease in older people requires further research to confirm.

Herpes zoster correlates with increased risk of Parkinson's disease in older people: A population-based cohort study in Taiwan

Little is known on the relationship between herpes zoster and Parkinson's disease in older people. This study aimed to explore whether herpes zoster could be associated with Parkinson's disease in older people in Taiwan.We conducted a retrospective cohort study using the claim data of the Taiwan National Health Insurance Program. There were 10,296 subjects aged 65 years and older with newly diagnosed herpes zoster as the herpes zoster group and 39,405 randomly selected subjects aged 65 years and older without a diagnosis of herpes zoster as the nonherpes zoster group from 1998 to 2010. Both groups were followed up until subjects received a diagnosis of Parkinson's disease. This follow-up design would explore whether subjects with herpes zoster were at an increased risk of Parkinson's disease. Relative risks were estimated by adjusted hazard ratio (HR) and 95% confidence interval (CI) using the multivariable Cox proportional hazards regression model.The incidence of Parkinson's disease was higher in the herpes zoster group than that in the nonherpes zoster group (4.86 vs 4.00 per 1000 person-years, 95% CI 1.14, 1.29). After adjustment for confounding factors, the multivariable Cox proportional hazards regression model revealed that the adjusted HR of Parkinson's disease was 1.17 for the herpes zoster group (95% CI 1.10, 1.25), compared with the nonherpes zoster group.Older people with herpes zoster confer a slightly increased hazard of developing Parkinson's disease when compared to those without herpes zoster. We think that herpes zoster correlates with increased risk of Parkinson's disease in older people. When older people with herpes zoster seek help, clinicians should pay more attention to the development of the cardinal symptoms of Parkinson's disease.

Increased Risk of Parkinson's Disease in Patients With Obstructive Sleep Apnea: A Population-Based, Propensity Score-Matched, Longitudinal Follow-Up Study

Obstructive sleep apnea (OSA), characterized by repetitive episodes of apnea/hypopnea and hypoxia, is associated with systemic inflammation and induces metabolic, endocrine, and cardiovascular diseases. Inflammation might have an impact on neurodegenerative diseases. This study investigates the possible association between OSA and Parkinson's disease (PD). Random samples out of 1 million individuals were collected from Taiwan's National Health Insurance database. A total of 16,730 patients with newly diagnosed OSA from 2002 to 2008 were recruited and compared with a cohort of 16,730 patients without OSA matched for age, gender, and comorbidities using propensity scoring. All patients were tracked until a diagnosis of PD, death, or the end of 2011.During the mean 5.6-year follow-up period, the incidence rates of PD were 2.30 per 1000 person-years in the OSA cohort and 1.71per 1000 person-years in the comparison group. The incidence rate ratio (IRR) for PD was greater in older patients (≧ 65 years) and male patients with OSA than the controls, respective IRRs being 1.34 and 1.47. After adjustment for the comorbidities, patients with OSA were 1.37 times more likely to have PD than patients without (95% CI = 1.12-1.68, P < 0.05). Subgroup analysis showed that older patients and patients with coronary artery disease, stroke, or chronic kidney disease had a higher risk for PD than their counter parts. Log-rank analysis revealed that patients with OSA had significantly higher cumulative incidence rates of PD than the comparison group (P = 0.0048). Patients with OSA are at an increased risk for subsequent PD, especially elderly male patients.