2023 Clinical Practice Guidelines for Diabetes Mellitus of the Korean Diabetes Association.

In May 2023, the Committee of Clinical Practice Guidelines of the Korean Diabetes Association published the revised clinical practice guidelines for Korean adults with diabetes and prediabetes. We incorporated the latest clinical research findings through a comprehensive systematic literature review and applied them in a manner suitable for the Korean population. These guidelines are designed for all healthcare providers nationwide, including physicians, diabetes experts, and certified diabetes educators who manage patients with diabetes or individuals at risk of developing diabetes. Based on recent changes in international guidelines and the results of a Korean epidemiological study, the recommended age for diabetes screening has been lowered. In collaboration with the relevant Korean medical societies, recently revised guidelines for managing hypertension and dyslipidemia in patients with diabetes have been incorporated into this guideline. An abridgment containing practical information on patient education and systematic management in the clinic was published separately.

Contribution of common and rare variants to Asian neovascular age-related macular degeneration subtypes.

Neovascular age-related macular degeneration (nAMD), along with its clinical subtype known as polypoidal choroidal vasculopathy (PCV), are among the leading causes of vision loss in elderly Asians. In a genome-wide association study (GWAS) comprising 3,128 nAMD (1,555 PCV and 1,573 typical nAMD), and 5,493 controls of East Asian ancestry, we identify twelve loci, of which four are novel ([Formula: see text]). Substantial genetic sharing between PCV and typical nAMD is noted (rg = 0.666), whereas collagen extracellular matrix and fibrosis-related pathways are more pronounced for PCV. Whole-exome sequencing in 259 PCV patients revealed functional rare variants burden in collagen type I alpha 1 chain gene (COL1A1; [Formula: see text]) and potential enrichment of functional rare mutations at AMD-associated loci. At the GATA binding protein 5 (GATA5) locus, the most significant GWAS novel loci, the expressions of genes including laminin subunit alpha 5 (Lama5), mitochondrial ribosome associated GTPase 2 (Mtg2), and collagen type IX alpha 3 chain (Col9A3), are significantly induced during retinal angiogenesis and subretinal fibrosis in murine models. Furthermore, retinoic acid increased the expression of LAMA5 and MTG2 in vitro. Taken together, our data provide insights into the genetic basis of AMD pathogenesis in the Asian population.

Retina-to-brain spreading of α-synuclein after intravitreal injection of preformed fibrils.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the aggregation of misfolded α-synuclein and progressive spreading of the aggregates from a few discrete regions to wider brain regions. Although PD has been classically considered a movement disorder, a large body of clinical evidence has revealed the progressive occurrence of non-motor symptoms. Patients present visual symptoms in the initial stages of the disease, and accumulation of phospho-α-synuclein, dopaminergic neuronal loss, and retinal thinning has been observed in the retinas of PD patients. Based on such human data, we hypothesized that α-synuclein aggregation can initiate in the retina and spread to the brain through the visual pathway. Here, we demonstrate accumulation of α-synuclein in the retinas and brains of naive mice after intravitreal injection of α-synuclein preformed fibrils (PFFs). Histological analyses showed deposition of phospho-α-synuclein inclusions within the retina 2 months after injection, with increased oxidative stress leading to loss of retinal ganglion cells and dopaminergic dysfunction. In addition, we found accumulation of phospho-α-synuclein in cortical areas with accompanying neuroinflammation after 5 months. Collectively, our findings suggest that retinal synucleinopathy lesions initiated by intravitreal injection of α-synuclein PFFs spread to various brain regions through the visual pathway in mice.

COVID-19 reduced scleral buckling training in fellows and shifted young ophthalmologists' preference toward vitrectomy: An Asia-Pacific survey.

BACKGROUND: To assess rhegmatogenous retinal detachment (RRD) surgery trends and training among young ophthalmologists (YOs, vitreoretinal fellows or attendings/consultants with ≤10 years of independent practice) and the impact of the COVID-19 pandemic. METHODS: An anonymous online survey was completed by 117 YOs in the Asia-Pacific regarding their RRD surgery experiences in 2021-2022. RESULTS: To achieve a 90% probability of surgical competency, 91 vitrectomy and 34 scleral buckling (SB) completions during fellowship were needed. In total, 49 (41.9%) YOs had fellowship affected by COVID-19. In the COVID versus pre-COVID era, however, the volume of SB completions per fellowship year decreased significantly (median [IQR] 3.3 [1.5, 9] vs. 13 [6.5, 23]; p < 0.001) and was lower than the required volume to achieve competency. YOs were less confident in conducting SB versus vitrectomy (3.5 ± 1.1 vs. 4.2 ± 0.8, p < 0.001), and they reported a decrease in the proportion of SB (-3.1%, p = 0.047) and an increase in the proportion of vitrectomy (+4.8%, p < 0.001) after the pandemic outbreak. Apart from RRD clinical characteristics, surgical confidence is among the main factors that affect surgical method decisions. During the pandemic, more YOs may have avoided SB due to the need for general anaesthesia, leading to longer surgical time and risk of viral transmission during intubation/extubation. CONCLUSIONS: SB surgical exposure is suboptimal in most fellowship programs in the 11 Asia-Pacific countries/regions we surveyed and further declined during the COVID-19 pandemic. YOs are less confident in performing SB, leading to a trend toward primary vitrectomy since the COVID-19 outbreak.

Sequential structural and functional change in geographic atrophy on multimodal imaging in non-exudative age-related macular degeneration.

PURPOSE: To investigate the temporal order of photoreceptor atrophy, retinal pigment epithelium (RPE) atrophy and visual acuity loss in patients with center-involving geographic atrophy (GA) in non-exudative age-related macular degeneration (neAMD). METHODS: Forty eyes of 25 consecutive patients who eventually developed center-involving GA were investigated. Fundus autofluorescence (FAF) and infrared image coupled optical coherence tomography (OCT) were acquired at each visit. Development of RPE atrophy and photoreceptor atrophy was defined as abnormal hyper/hypo-fluorescence on FAF and photoreceptor loss on OCT over 50% of the vertical or horizontal diameters of the center 1 mm circle, respectively. Visual acuity loss was defined as worsening of more than 0.2 logMAR compared to baseline. Kaplan-Meier analyses was performed to compare the sequential order of these three events. RESULTS: Mean age was 72.72 ± 8.63 years, and follow-up duration was 27.36 ± 17.22 months, with an average number of visits of 3.04 ± 1.54 during follow-up. GA progressed from photoreceptor atrophy on OCT, RPE atrophy on FAF, and then to vision loss (p < 0.001). The median survival time of photoreceptors preceded that of visual acuity by 16.3 months, and the median survival time of RPE preceded that of visual acuity by 7.0 months. At baseline, majority of eyes showed drusen only (57.5%), while the most common feature was incomplete RPE and outer retinal atrophy at 3-year follow-up (40.4%). CONCLUSION: In the progression of center-involving GA, photoreceptor atrophy on OCT and RPE atrophy on FAF precedes visual decline, and can act as biomarkers predicting future visual decline within the following years.

Comparison of Optical Coherence Tomography Biomarkers between Bevacizumab Good Responders and Nonresponders Who were Switched to Dexamethasone Implant in Diabetic Macular Edema.

PURPOSE: To compare volumetric optical coherence tomography (OCT) biomarkers in bevacizumab responsive and bevacizumab refractory diabetic macular edema (DME) patients switched to the dexamethasone implant to ultimately identify possible prognostic indicators. METHODS: Retrospective analysis of DME patients treated with bevacizumab were done. Patients were divided into those who showed response to bevacizumab (bevacizumab only group) and others who were switched to the dexamethasone implant due to lack of response to bevacizumab (switching group). Volumetric OCT biomarkers such as central macular thickness (CMT), inner and outer cystoid macular edema (CME) volume, serous retinal detachment (SRD) volume, retinal volume (CME + SRD volume) within the 6-mm Early Treatment of Diabetic Retinopathy Study circle were calculated. OCT biomarkers were followed up throughout treatment. RESULTS: Among total of 144 eyes, 113 patients were included in the bevacizumab only group and 31 patients were included in the switching group. Compared to the bevacizumab only group, the switching group showed higher baseline CMT (558.00 ± 209.60 µm vs. 454.96 ± 125.88 µm, p = 0.003), larger inner CME (6.02 ± 1.43 mm3 vs. 5.12 ± 0.87 mm3, p = 0.004) and SRD volume (0.32 ± 0.40 mm3 vs. 0.11 ± 0.09 mm3, p = 0.015) and higher proportion of patients with SRD (58.06% vs. 31.86%, p = 0.008). In the switching group, CMT, inner CME and SRD volume all showed significant reduction after switching to the dexamethasone implant. CONCLUSIONS: DME with large SRD and inner nuclear layer edema volume may be more effectively treated with the dexamethasone implant than bevacizumab.

Assessment of Risk Factors Affecting Refractive Outcomes after Phacovitrectomy for Epiretinal Membrane.

PURPOSE: To investigate factors associated with refractive outcomes after phacovitrectomy for epiretinal membrane (ERM). METHODS: Retrospective review of patients undergoing phacovitrectomy for ERM was done. The main outcome measure was predictive refraction error (PE), defined as observed refraction error - target refraction error, calculated by the SRK/T, Haigis, and SRK II formulae. PE was measured at postoperative 1, 3, and 6 months. Simple and multiple linear regression analysis were used to evaluate factors associated with PE. RESULTS: A total of 53 eyes of 53 patients were included. The mean PEs at postoperative 1, 3, and 6 months were all negative, implying myopic shift in all patients regardless of the intraocular lens formula used. Haigis formula showed the least myopic shift among the three formulae (p = 0.001, Friedman test). There was no significant difference in PE depending on preoperative central macular thickness (CMT) in subgroup analysis. On stepwise multiple linear regression analysis, ERM etiology (ß = 0.759, p = 0.004, SRK/T formula; ß = 0.733, p = 0.008, Haigis formula; ß = 0.933, p < 0.001, SRK II formula), preoperative anterior chamber depth (ß = -0.662, p = 0.013, Haigis formula; ß = -0.747, p = 0.003, SRK II formula), and decrease of CMT (ß = -0.003, p = 0.025, SRK/T formula) were significantly associated with PE at postoperative 6 months. CONCLUSIONS: Myopic shift in PE was observed after combined phacovitrectomy for epiretinal membrane. ERM etiology, preoperative anterior chamber depth, and decrease of CMT were significantly associated with PE at postoperative 6 months. There was no difference in PE after surgery between the two groups defined by CMT (≥500 and <500 µm).

Pathogenic Risk Factors and Associated Outcomes in the Bullous Variant of Central Serous Chorioretinopathy.

PURPOSE: To compare the clinical features, treatments, and outcomes between bullous and chronic variants of central serous chorioretinopathy (CSC). DESIGN: Retrospective, observational case series. PARTICIPANTS: Sixty-two eyes of 44 patients with bullous-variant CSC (bvCSC) and 97 eyes of 85 patients with nonbullous CSC. METHODS: We conducted a national survey between September 1, 2020, and March 31, 2021, of members of the Korean Retina Society and obtained data of patients with bvCSC from 11 retinal centers. A comparator group comprised consecutive chronic CSC patients without bullous detachment. MAIN OUTCOME MEASURES: Baseline demographics and patient characteristics were compared between groups. Secondary outcomes included factors associated with visual prognosis within the bvCSC group. RESULTS: Compared with the nonbullous CSC group, the bvCSC group presented at a younger age (49 vs. 52 years; P = 0.047) and with more bilateral involvement (41% vs. 14%; P < 0.001). Systemic corticosteroid use was more prevalent in the bvCSC group, both in terms of any exposure (50% vs. 20%; P = 0.001) and long-term exposure (36% vs. 9%; P < 0.001). The bvCSC group had distinct imaging features (all P < 0.05): retinal folding (64% vs. 1%), subretinal fibrin (75% vs. 13%), multiple retinal pigment epithelium tears (24% vs. 2%), and multifocal fluorescein leakages with terminal telangiectasia (36% vs. 1%). Although bvCSC patients had worse vision at diagnosis (20/80 vs. 20/44; P = 0.003), treatment response was more robust (fluid resolution by final follow-up, 84% vs. 68%; P = 0.034) even with conservative management, resulting in similar final vision (20/52 vs. 20/45; P = 0.52). History of kidney-related (odds ratio [OR] 5.4; 95% confidence interval [CI] 1.3-18.5; P = 0.045) and autoimmune/rheumatoid diseases (OR 25.4, 95% CI 2.8-195.0; P = 0.004) showed associations with the bvCSC group. Apart from vision at diagnosis (OR 0.1, 95% CI 0.05-0.36; P < 0.001), a history of renal transplantation was most predictive of visual prognoses for bvCSC eyes (OR 0.2, 95% CI 0.04-0.75; P = 0.020). CONCLUSIONS: Bullous-variant CSC may be associated with pathogenic risk factors based on underlying medical conditions and systemic corticosteroid use. Poor vision at diagnosis and history of renal transplantation were associated with poor visual outcome.

Peripapillary retinal nerve fiber layer thinning in patients with progressive supranuclear palsy.

OBJECTIVES: To investigate peripapillary retinal nerve fiber layer (pRNFL) changes in patients with progressive supranuclear palsy (PSP). METHODS: We included 21 PSP patients (36 eyes) who underwent peripapillary optical coherence tomography (OCT) scans at 2.5 ± 1.3 years of disease, without ophthalmologic co-morbidities. We compared pRNFL thicknesses in PSP eyes with age-matched 22 controls (22 eyes) using generalized estimating equation model adjusting for intra-subject inter-eye correlations, age and sex. We also analyzed the correlation between the pRNFL thickness and clinical severity using Spearman's correlation. In twelve PSP patients with 3 T brain MRI volumetric scan within 1 year of OCT exam, we investigated the correlation between the pRNFL thickness and brain atrophy using Pearson's correlation. RESULTS: PSP patients had global pRNFL thinning compared to controls (beta = - 6.436, p = 0.025). Global pRNFL thickness correlated with Hoehn & Yahr stages (r = - 0.487, p = 0.025), and nasal pRNFL thinning showed a trend of correlation (uncorrected p < 0.05). Exploratory correlation analysis between global pRNFL thickness and nonmotor items in the PSP rating scale showed a trend toward association with sleep disturbances (uncorrected p = 0.008) and urinary incontinence (uncorrected p = 0.031), although not significant after Bonferroni correction (all 28 items). The patients had significant atrophy in the posterior cingulate cortex, third ventricle, pallidum, and midbrain with reduced midbrain-to-pons ratio, but no correlation was found between pRNFL thickness and brain volumes. CONCLUSION: The pRNFL seems to be affected in PSP, which is more severe with advanced disease stages. Retinal investigation in a larger longitudinal cohort would help elucidate the pathophysiological role of retinal thinning in PSP.

Expanding the clinical phenotype in patients with disease causing variants associated with atypical Usher syndrome.

Atypical Usher syndrome (USH) is poorly defined with a broad clinical spectrum. Here, we characterize the clinical phenotype of disease caused by variants in CEP78, CEP250, ARSG, and ABHD12.Chart review evaluating demographic, clinical, imaging, and genetic findings of 19 patients from 18 families with a clinical diagnosis of retinal disease and confirmed disease-causing variants in CEP78, CEP250, ARSG, or ABHD12.CEP78-related disease included sensorineural hearing loss (SNHL) in 6/7 patients and demonstrated a broad phenotypic spectrum including: vascular attenuation, pallor of the optic disc, intraretinal pigment, retinal pigment epithelium mottling, areas of mid-peripheral hypo-autofluorescence, outer retinal atrophy, mild pigmentary changes in the macula, foveal hypo-autofluorescence, and granularity of the ellipsoid zone. Nonsense and frameshift variants in CEP250 showed mild retinal disease with progressive, non-congenital SNHL. ARSG variants resulted in a characteristic pericentral pattern of hypo-autofluorescence with one patient reporting non-congenital SNHL. ABHD12-related disease showed rod-cone dystrophy with macular involvement, early and severe decreased best corrected visual acuity, and non-congenital SNHL ranging from unreported to severe.This study serves to expand the clinical phenotypes of atypical USH. Given the variable findings, atypical USH should be considered in patients with peripheral and macular retinal disease even without the typical RP phenotype especially when SNHL is noted. Additionally, genetic screening may be useful in patients who have clinical symptoms and retinal findings even in the absence of known SNHL given the variability of atypical USH.

Characterization of the Spectrum of Ophthalmic Changes in Patients With Alagille Syndrome.

Purpose: The purpose of this study was to characterize the phenotypic spectrum of ophthalmic findings in patients with Alagille syndrome. Methods: We conducted a retrospective, observational, multicenter, study on 46 eyes of 23 subjects with Alagille syndrome. We reviewed systemic and ophthalmologic data extracted from medical records, color fundus photography, fundus autofluorescence, optical coherence tomography, visual fields, electrophysiological assessments, and molecular genetic findings. Results: Cardiovascular abnormalities were found in 83% of all cases (of those, 74% had cardiac murmur), whereas 61% had a positive history of hepatobiliary issues, and musculoskeletal anomalies were present in 61% of all patients. Dysmorphic facies were present in 16 patients, with a broad forehead being the most frequent feature. Ocular symptoms were found in 91%, with peripheral vision loss being the most frequent complaint. Median (range) Snellen visual acuity of all eyes was 20/25 (20/20 to hand motion [HM]). Anterior segment abnormalities were present in 74% of the patients; of those, posterior embryotoxon was the most frequent finding. Abnormalities of the optic disc were found in 52%, and peripheral retinal abnormalities were the most frequent ocular finding in this series, found in 96% of all patients. Fifteen JAG1 mutations were identified in 16 individuals; of those, 6 were novel. Conclusions: This study reports a cohort of patients with Alagille syndrome in which peripheral chorioretinal changes were more frequent than posterior embryotoxon, the most frequent ocular finding according to a number of previous studies. We propose that these peripheral chorioretinal changes are a new hallmark to help diagnose this syndrome.

INFECTIOUS ENDOPHTHALMITIS AFTER SCLERAL FIXATION OF AN INTRAOCULAR LENS.

PURPOSE: To determine the mechanism of infection, clinical features, and risk factors of endophthalmitis after scleral fixation of an intraocular lens. METHODS: We included 15 patients with infectious endophthalmitis after scleral fixation of an intraocular lens between April 2004 and December 2017, as well as four patients found through a literature search. Thus, a total of 19 patients were analyzed. RESULTS: Among 19 eyes, infectious endophthalmitis developed at a mean of 23 months (range: 1 day-10 years) after scleral fixation surgery. Nine eyes (47.4%) had early-onset endophthalmitis (≤6 weeks), and 10 eyes (52.6%) had delayed-onset endophthalmitis (>6 weeks). Eleven eyes (57.9%) had presumed microbial influx due to suture exposure. Those with delayed-onset endophthalmitis showed a higher rate of suture-related infection (80.0% vs. 33.3%) and culture of gram-negative bacteria (70.0% vs. 12.5%) than did those with early-onset endophthalmitis. CONCLUSIONS: Infectious endophthalmitis can develop late after scleral fixation of an intraocular lens, usually related to the exposed sutures, and the visual prognosis is poor. Eyes that have sutured scleral fixation should be monitored regularly, and preventive measures should be performed if an exposed suture is found.

Genome-wide association studies identify two novel loci conferring susceptibility to diabetic retinopathy in Japanese patients with type 2 diabetes.

Several reports have suggested that genetic susceptibility contributes to the development and progression of diabetic retinopathy. We aimed to identify genetic loci that confer susceptibility to diabetic retinopathy in Japanese patients with type 2 diabetes. We analysed 5 790 508 single nucleotide polymorphisms (SNPs) in 8880 Japanese patients with type 2 diabetes, 4839 retinopathy cases and 4041 controls, as well as 2217 independent Japanese patients with type 2 diabetes, 693 retinopathy cases and 1524 controls. The results of these two genome-wide association studies (GWAS) were combined with an inverse variance meta-analysis (Stage-1), followed by de novo genotyping for the candidate SNP loci (P < 1.0 × 10-4) in an independent case-control study (Stage-2, 2260 cases and 723 controls). After combining the association data (Stages 1 and 2) using meta-analysis, the associations of two loci reached a genome-wide significance level: rs12630354 near STT3B on chromosome 3, P = 1.62 × 10-9, odds ratio (OR) = 1.17, 95% confidence interval (CI) 1.11-1.23, and rs140508424 within PALM2 on chromosome 9, P = 4.19 × 10-8, OR = 1.61, 95% CI 1.36-1.91. However, the association of these two loci was not replicated in Korean, European or African American populations. Gene-based analysis using Stage-1 GWAS data identified a gene-level association of EHD3 with susceptibility to diabetic retinopathy (P = 2.17 × 10-6). In conclusion, we identified two novel SNP loci, STT3B and PALM2, and a novel gene, EHD3, that confers susceptibility to diabetic retinopathy; however, further replication studies are required to validate these associations.

Efficacy of bevacizumab for vitreous haemorrhage in proliferative diabetic retinopathy with prior complete panretinal photocoagulation.

PURPOSE: To investigate the efficacy of intravitreal bevacizumab injections (IVBs) for vitreous haemorrhage (VH) in proliferative diabetic retinopathy (PDR) with prior complete panretinal photocoagulation (PRP). METHODS: A multicentre cohort study of eyes with new VH in PDR after documented previous complete PRP was performed. Eyes were grouped according to IVB treatment at baseline, and cumulative rate of vitrectomy and spontaneous clear-up rate were compared as the main outcome. Eyes requiring vitrectomy within 1 month, or with tractional retinal detachment (TRD), or with spontaneous clear-up within 1 month, were excluded. RESULTS: In total, 44 eyes with IVB and 92 control eyes without IVB were followed up to 20.1 months. Cumulative probability of vitrectomy was lower in the IVB group at 12 months (0.16 vs 0.42, IVB vs controls), and throughout the follow-up period (p = 0.005). Cumulative probability of spontaneous clear-up was higher in the IVB group at 12 months (0.81 vs 0.68, IVB vs controls), and throughout the follow-up period (p = 0.013). Best-corrected visual acuity (BCVA) at 1 month after onset of VH was significantly better in the IVB group (0.513 vs 0.942 logarithm of the minimal angle of resolution, p = 0.002); however, the difference of BCVA lost significance with further follow-up. IVB treatment was the only factor significantly associated with vitrectomy risk on multivariate analysis (p = 0.047, hazard ratio 0.506). CONCLUSION: In VH after prior complete PRP, IVB was effective in decreasing vitrectomy requirement, although overall visual benefit was short-term. IVB can be considered to defer vitrectomy in PDR VH eyes with prior complete PRP and no TRD.

Novel mutation in SLC4A7 gene causing autosomal recessive progressive rod-cone dystrophy.

BACKGROUND: Recent advances in genetic sequencing techniques have improved the overall diagnostic yield for finding genetic causes for inherited retinal dystrophies (IRD). Rod-cone dystrophy is the most common IRD and is characterized by the primary involvement of the rod photoreceptors. Over 80 causal genes have been identified so far giving clinicians insight into the pathogenesis. SLC4A7 encodes a sodium bicarbonate cotransporter responsible acid disposal which, within the retina, is prevalent in the photoreceptor synaptic terminals. Thus far, there have been no published reports of variants in this gene known to cause rod-cone dystrophy. MATERIAL AND METHODS: Case report of a rod-cone dystrophy patient with a novel mutation in SLC4A7, whole exome sequencing with CLIA-certified NGS and Sanger confirmation, and, review of a SLC4A7 knockout mouse model phenotype. RESULTS: A 66-year-old male presented with slowly progressing night blindness, constricted visual field and relatively stable visual acuity. Fundus examination showed diffuse intraretinal pigment in the mid- and peripheral retina, diffuse retinal pigment epithelial atrophy, and intact macula in both eyes. There has been mild macular edema in both eyes which remained stable with the use of topical dorzolamide eyedrops. Whole exome sequencing found, and a subsequent vision panel confirmed, the pathogenic variant to be a homozygous frameshift mutation in SLC4A7 which results in termination of the protein. CONCLUSIONS: We report a case of progressive rod-cone dystrophy caused by a novel mutation in SLC4A7, a gene coding the sodium bicarbonate cotransporter NBC3, underscoring the importance of ion homeostasis for photoreceptor function and maintenance.

Contrast sensitivity impairment in drug-naïve Parkinson's disease patients associates with early cognitive decline.

OBJECTIVES: To investigate the contrast sensitivity function in drug-naïve Parkinson's disease (PD) patients and its predictive value with longitudinal follow-up data. METHODS: We included newly diagnosed non-demented PD patients who performed contrast sensitivity test between 2013 and 2014. Contrast sensitivity function at drug-naïve state in PD patients was compared with age-matched normal control data of our center. Correlation between contrast sensitivity function and parkinsonian motor and non-motor features including the Mini-Mental State Exam (MMSE) score at the time of diagnosis were analyzed by linear regression. With longitudinal follow-up data after initiating anti-parkinsonian therapy, the risk conferred on subsequent visual hallucinations and cognitive impairment requiring anti-dementia drugs was analyzed by dichotomizing PD group based on the initial contrast sensitivity function. RESULTS: Forty-eight patients were finally included, and mean follow-up periods were 43 months. Contrast sensitivity function in drug-naïve PD patients was significantly worse than controls. Contrast sensitivity function correlated with sleep disturbance (p = 0.001) and global cognitive status reflected by the MMSE score (p = 0.020). It also associated with further decline in the MMSE during the follow-ups (p = 0.029). Patients with below average contrast sensitivity function at the time of diagnosis showed higher risk of cognitive decline requiring anti-dementia drugs (adjusted odds ratio = 4.68, p = 0.04) and of visual hallucinations (adjusted odds ratio = 12.54, p = 0.04) than those above average function during the follow-up. CONCLUSION: Contrast sensitivity impairment in drug-naïve PD patients associates with clinical demand for therapeutic intervention of cognitive decline as well as development of visual hallucinations in the early course of the disease.