Inter-grader reliability in the Danish screening programme for diabetic retinopathy

PURPOSE

The Danish Registry of Diabetic Retinopathy includes information from >200 000 patients who attends diabetic retinopathy (DR) screening in Denmark. Screening of patients with uncomplicated type 2 diabetes is often performed by practicing ophthalmologists, while patients with type 1 and complicated type 2 diabetes attends screening at hospitals. We performed a clinical reliability study of retinal images from Danish screening facilities to explore the inter-grader agreement between the primary screening ophthalmologist and a blinded, certified grader.

METHODS

Invitations to participate were sent to screening facilities across Denmark. The primary grader uploaded fundus photographs with information on estimated level of DR (International Clinical Diabetic Retinopathy scale as 0 [no DR], 1-3 [mild, moderate or severe nonproliferative DR {NPDR}], or 4 [proliferative DR {PDR}]), region of screening, image style, and screening facility. Images were then regraded by a blinded, certified, secondary grader. Weighted kappa analysis was performed to evaluate agreement.

RESULTS

Fundus photographs from 230 patients (458 eyes) were received from practicing ophthalmologists (52.6%) and hospital-based grading centres (47.4%) from all Danish regions. Reported levels of DR by the primary graders were 66.8%, 12.2%, 13.1%, 1.3% and 5.5% for DR levels 0-4. The overall agreement between primary and secondary graders was 93% (κ = 0.83). Based on screening facility agreement was 96% (κ = 0.89) and 90% (κ = 0.76) for practicing ophthalmologists and hospital-based graders.

CONCLUSION

In this nationwide study, we observed a high overall inter-grader agreement and based on this, it is reasonable to assume that reported DR gradings in the screening programme in Denmark, accurately reflect the truth.

Retinal vein occlusion as an age-dependent marker of incident dementia in a long-term Danish national cohort

PURPOSE

The aim of this study was to investigate retinal vein occlusion (RVO) as an independent marker of incident dementia.

METHODS

In a prospective nationwide cohort study, we identified 2 225 568 individuals through the Danish national health registers. Individuals older than 65 years, without unspecified retinal vascular occlusion or dementia were included from 1998 to 2020 and followed until 2022. We calculated the incidence rate (IR) and performed a Cox regression analysis with a hazard ratio (HR) and 95% confidence interval (CI) for RVO (exposure) as a marker of all-cause dementia adjusted for systemic comorbidity.

RESULTS

We identified 19 669 individuals with RVO who had a higher prevalence of systemic comorbidity at inclusion compared to those without RVO (n = 2 185 483). We performed a Cox regression analysis for age-dependent exposure due to non-proportional hazards in the pre-planned analysis. Exposed individuals younger than 75 years had an increased risk of all-cause dementia (adjusted HR 1.09, 95% CI 1.01-1.18), whereas individuals older than 75 years had a decreased risk of all-cause dementia (adjusted HR 0.92, 95% CI 0.86-0.98).

CONCLUSION

Individuals with RVO had an age-dependent risk of dementia, with a 9% increased risk in individuals with RVO younger than 75 years and an 8% decreased risk in individuals older than 75 years at the time of exposure.

Retinal artery occlusion does not act as an independent marker of upcoming dementia: results from a Danish 20-year cohort study

PURPOSE

Retinal artery occlusion (RAO) is a vision threatening disease associated with cerebral vascular dysfunction, which may reflect initial signs of cerebral pathology. Early detection of patients in risk of dementia could allow for preventative treatment. Hence, this study aimed to investigate RAO as an independent biomarker of incident dementia.

METHODS

This study was a nationwide, 20-year longitudinal cohort study in Denmark with inclusion from 1998 to 2020 and follow up until the end of 2022. We identified 2 205 159 individuals aged 65 or older through the Danish national health registers and monitored RAO (exposure) and dementia (outcome) status. We calculated incidence rate and performed a Cox regression analysis with hazard ratio (HR) and 95% confidence interval (CI) for RAO as a marker of dementia in a crude, a semi-adjusted (age and sex), and a fully adjusted model (furthermore adjusted for marital status and systemic comorbidity.) RESULTS: We identified 8 863 individuals with RAO. Incidence rates were higher among exposed compared to unexposed individuals (12.28 and 8.18 per 1000 person-years at risk, respectively). Individuals with RAO were more likely to be male and older at inclusion, to have hypertension, dyslipidaemia, cardiovascular disease, chronic kidney disease, and diabetes (p < 0.001). RAO was not associated with all-cause dementia in the crude analysis (HR 1.07 CI [1.00-1.17]) or in the fully adjusted analysis (HR 0.98 CI [0.91-1.06].

CONCLUSION

Although individuals with RAO had a higher incidence of dementia compared to unexposed individuals, these associations were lost when confounders were taken into account.

Predictive value of retinal oximetry, optical coherence tomography angiography and microperimetry in patients with treatment-naïve branch retinal vein occlusion

Vascular endothelial growth factor inhibitors have substantially improved the visual outcomes in patients with macular edema (ME) caused by branch retinal vein occlusion (BRVO), but treatment outcomes are highly variable and early prediction of expected clinical outcome would be important for individualized treatment.As non-invasive metabolic, structural and functional retinal markers might act as early predictors of clinical outcomes, we performed a 12-month, prospective study aimed to evaluate if baseline retinal oximetry, optical coherence tomography angiography (OCT-A) or microperimetry were able to predict need of treatment, structural or functional outcome in patients with ME caused by treatment-näive BRVO.We evaluated 41 eyes of 41 patients with a mean age of 69.6 years and 56% females. We found a strong tendency towards a higher retinal arteriolar oxygen saturation in patients without a need of additional aflibercept treatment after the loading phase (99.8% vs. 92.3%, adjusted odds ratio 0.80 (95% confidence interval 0.64-1.00), adjusted p = 0.058), but otherwise, retinal oximetry, OCT-A or microperimetry were not able to predict need of treatment, structural nor functional outcomes. (Trial registration: clinicaltrials.gov, S-20,170,084. Registered 24 August 2014, https://clinicaltrials.gov/ct2/show/NCT03651011 ).

Presence and development of diabetic retinopathy in 153 238 patients with type 2 diabetes in the Danish Registry of Diabetic Retinopathy

PURPOSE

The purpose of the study was to evaluate the prevalence and incidence of diabetic retinopathy (DR) along with associated markers in patients with type 2 diabetes in the Danish DR-screening programme.

METHODS

We included all persons with type 2 diabetes in the Danish Registry of Diabetic Retinopathy, who had attended at least one episode of DR screening in 2013-2018. DR was classified as levels 0-4 indicating increasing severity. Data were linked with various national health registries to retrieve information on diabetes duration, marital status, comorbidity and systemic medication.

RESULTS

Among 153 238 persons with type 2 diabetes, median age and duration of diabetes were 66.9 and 5.3 years and 56.4% were males. Prevalence and 5-year incidences of DR, 2-step-or-more progression of DR and progression to proliferative DR (PDR) were 8.8%, 3.8%, 0.7% and 0.2%, respectively. In multivariable models, leading markers of incident DR and progression to PDR were duration of diabetes (HR 1.98, 95% CI 1.87-2.09; HR 2.89, 95% CI 2.34-3.58 per 10 years of duration) and use of insulin (HR 1.88, 95% CI 1.76-2.01; HR 2.40, 95% CI 1.84-3.13), while the use of cholesterol-lowering medicine was a protecting marker (HR 0.87, 95% CI 0.81-0.93; HR 0.70, 95% CI 0.52-0.93). From 2013 to 2015, 3-year incidence rates of PDR decreased from 1.22 to 0.45 events per 1000 person-years.

CONCLUSION

Nationally, among Danish individuals with type 2 diabetes attending DR screening, we identified duration of diabetes and use of insulin as the most important predictor for the development of DR, while cholesterol-lowering medicine was a protective factor.

Bidirectional 5-year risks of diabetic retinopathy, glaucoma and/or ocular hypertension: Results from a national screening programme

PURPOSE

We aimed to investigate if diabetic retinopathy (DR), glaucoma and/or ocular hypertension (OHT) are prospectively linked, as previous studies have proposed cross-sectional associations, but longitudinal data from larger cohorts are lacking.

METHODS

We performed a bidirectional 5 years prospective, registry-based cohort study. We extracted data from national registers, including the Danish Registry of Diabetic Retinopathy, the Danish Civil Registration System, the Danish National Patient Register and the Danish National Prescription Registry. DR level was defined by the highest level of the two eyes. Glaucoma and/or OHT was defined by diagnostic codes (H40*) or at least three redeemed prescriptions of glaucoma medication (S01E*) within 1 year. We included 205 970 persons with diabetes and 1 003 170 age- and gender-matched non-diabetes controls. Exposures were level-specific DR (i) and glaucoma and/or OHT (ii), and outcomes were hazard ratios (HRs) for 5 years incident glaucoma and/or OHT (i) and DR (ii).

RESULTS

Persons with diabetes were more likely to develop glaucoma and/or OHT (multivariable adjusted HR 1.11, 95% CI 1.06-1.15), but this did not depend on the level of DR. In persons with diabetes, those with glaucoma and/or OHT were more likely to develop DR (multivariable adjusted HR 1.12, 95% CI 1.03-1.23) within 5 years.

CONCLUSION

In a national cohort, diabetes associated with a little higher risk of upcoming glaucoma and/or OHT, and, inversely, the presence of the latter predicted a higher risk of incident DR. Nevertheless, our data do not seem to justify including glaucoma evaluation in the national Danish DR-screening programme.

Attendance in a national screening program for diabetic retinopathy: a population-based study of 205,970 patients

AIMS

A nationwide diabetic retinopathy (DR) screening program has been established in Denmark since 2013. We aimed to perform an evaluation of adherence to DR screenings and to examine whether non-adherence was correlated to DR progression.

METHODS

The population consisted of a register-based cohort, who participated in the screening program from 2013 to 2018. We analyzed age, gender, marital status, DR level (International Clinical DR severity scale, none, mild-, moderate-, severe non-proliferative DR (NPDR) and proliferative DR (PDR)), comorbidities and socioeconomic factors. The attendance pattern of patients was grouped as either timely (no delays > 33%), delayed (delays > 33%) or one-time attendance (unexplained).

RESULTS

We included 205,970 patients with 591,136 screenings. Rates of timely, delayed and one-time attendance were 53.0%, 35.5% and 11.5%, respectively. DR level at baseline was associated with delays (mild-, moderate-, severe NPDR and PDR) and one-time attendance (moderate-, severe NPDR and PDR) with relative risk ratios (RRR) of 1.68, 2.27, 3.14, 2.44 and 1.18, 2.07, 1.26, respectively (P < 0.05). Delays at previous screenings were associated with progression to severe NPDR or PDR (hazard ratio (HR) 2.27, 6.25 and 12.84 for 1, 2 and 3+ delays, respectively). Any given delay doubled the risk of progression (HR 2.28).

CONCLUSIONS

In a national cohort of 205,970 patients, almost half of the patients attended DR screening later than scheduled or dropped out after first screening episode. This was, in particular, true for patients with any levels of DR at baseline. DR progression in patients with delayed attendance, increased with the number of missed appointments.

Navigated laser and aflibercept versus aflibercept monotherapy in treatment-naïve branch retinal vein occlusion: A 12-month randomized trial

PURPOSE

Angiostatic agents have proven effective in the treatment of macular oedema in patients with branch retinal vein occlusion (BRVO). However, treatment is inconvenient and expensive, and novel treatment regimens are warranted. We aimed to evaluate if combination treatment of navigated central retinal laser and aflibercept lowered the treatment burden in these patients.

METHODS

Treatment-naïve patients with BRVO and macular oedema were included at two centres and randomized 1:1 to three monthly injections of 2.0 mg aflibercept with (Group A) or without (Group B) navigated central laser, followed by aflibercept as needed from month 4 through 12. Re-treatment need was evaluated, and secondary endpoints included functional and anatomical outcomes and safety evaluated by retinal microperimetry.

RESULTS

We evaluated 41 eyes of 41 patients with a mean age of 69.6 years. Baseline median best-corrected visual acuity (BCVA) was 70.0 letters, and median central retinal thickness (CRT) was 502 μm with no difference between Groups A (n = 21) and B (n = 20). Percentage of patients needing re-treatment after month three was 71% and 80% (p = 0.72). At month 12, groups did not differ in number of injections after loading (1 versus 2, p = 0.43), change in BCVA (+12.8 versus +15.1 letters, p = 0.48), CRT (-195 versus -181 μm, p = 0.82), or retinal sensitivity (+3.3 versus +4.1 dB, p = 0.67).

CONCLUSION

In treatment-naïve BRVO patients, addition of navigated central laser to aflibercept did not lower treatment burden or affect functional or anatomical outcomes. A low number of intravitreal injections were needed for successful outcome in both treatment arms.

Diabetic Retinopathy Predicts Risk of Alzheimer’s Disease: A Danish Registry-Based Nationwide Cohort Study

Background:

Retinal neurodegeneration is evident in early diabetic retinopathy (DR) which may be associated with other neurodegenerative diseases like Alzheimer's disease (AD).

Objective:

To investigate diabetes and DR as a risk marker of present and incident AD.

Methods:

A register-based cohort study was performed. We included 134,327 persons with diabetes above 60 years of age, who had attended DR screening, and 651,936 age- and gender-matched persons without diabetes.

Results:

At baseline, the prevalence of AD was 0.7% and 1.3% among patients with and without diabetes, respectively. In a multivariable regression model, patients with diabetes were less likely to have AD at baseline (adjusted OR 0.63, 95% CI 0.59–0.68). During follow-up, incident AD was registered for 1473 (0.35%) and 6,899 (0.34%) persons with and without diabetes, respectively. Compared to persons without diabetes, persons with diabetes and no DR had a lower risk to develop AD (adjusted HR 0.87, 95% CI 0.81–0.93), while persons with diabetes and DR had higher risk of AD (adjusted HR 1.24, 95% CI 1.08–1.43). When persons with diabetes and no DR were used as references, a higher risk of incident AD was observed in persons with DR (adjusted HR 1.34, 95% CI 1.18–1.53).

Conclusion:

Individuals with diabetes without DR were less likely to develop AD compared to persons without diabetes. However, individuals with DR had a 34% higher risk of incident AD, which raise the question whether screening for cognitive impairment should be done among individuals with DR.

Licorice-induced apparent mineralocorticoid excess compounded by excessive use of terbutaline and high water intake

This case highlights the clinical course of a 54-year-old male patient presenting with hypertension and long-term refractory hypokalaemia. He reported long-term malaise, fatigue and physical discomfort. Diarrhoea, vomiting, over-the-counter drugs, dietary supplements and any kind of medical abuse were all denied. Physical examination was normal. Suppressed plasma renin activity along with a low aldosterone level and elevated urinary cortisone/cortisol metabolite excretion ratio raised the suspicion of apparent mineralocorticoid excess (AME). The patient started treatment with spironolactone, but serum potassium levels were persistently fluctuating and the patient was hospitalised for further evaluation. During hospitalisation, repeated medical history and diagnostic examinations revealed licorice-induced AME complicated by excessive use of terbutaline and massive water intake. Licorice discontinuation, reduction of terbutaline and normalisation of water intake led to fully normalised potassium levels. Despite careful clinical history and diagnostic work-up, hospitalisation may be necessary in selected patients with long-term hypokalaemia.