A Nationwide Cohort Study on the Association Between Past Physical Activity and Neovascular Age-Related Macular Degeneration in an East Asian Population

Sex differences in prognosis factors in patients with lung cancer: A nationwide retrospective cohort study in Korea

Large-scale studies elucidating sex differences in factors impacting prognosis and sex-specific prognossis factors scoring in patients with lung cancer are insufficient. The present study aimed to develop a model to predict sex-specific prognosis factors in Korean patients with lung cancer. This nationwide cohort study included 96,255 patients aged ≥19 years diagnosed with lung cancer and underwent Korean National Health Insurance Service health examinations between January 1, 2005 and December 31, 2015 and followed until 2020. Factors associated with prognosis were estimated using multivariable Cox proportional hazards regression analyses, and separate prognosis scores were calculated for male and female patients. The sex-specific risk scoring models were validated with Kaplan-Meier survival curves and c-statistic. During a mean follow-up of 2.8 years, 60.5% of the patients died. In male patients with lung cancer, age ≥ 65 years (24 points) had the highest mortality risk score, followed by chemotherapy in combination with radiotherapy (16 points), chemotherapy (14 points), and radiotherapy (11 points). In female patients with lung cancer, chemotherapy in combination with radiotherapy (19 points) had the highest mortality risk score, followed by chemotherapy (16 points), age ≥ 65 years (13 points), and radiotherapy (13 points). The analysis of patients categorized into three risk groups based on risk scores revealed that the fatality rates within 5 years were 7%, 54%, and 89% in the low-, intermediate-, and high-risk groups for male patients and 3%, 46%, 85% in the low-, intermediate-, and high-risk groups for female patients, respectively. The c-statistic was 0.86 for male patients and 0.85 for female patients. The strongest fatality risk factors in lung cancer were age ≥ 65 years in male patients and chemotherapy in female patients. The present study developed sex-specific prognosis scoring models to predict fatality risk in patients with lung cancer.

Intermittent Fasting Is Associated With a Decreased Risk of Age-Related Macular Degeneration

PURPOSE

To investigate the association between intermittent fasting and age-related macular degeneration (AMD) in the general older adult population.

DESIGN

A cross-sectional study using a population-based, government-led survey data, Korean National Health and Nutrition Examination Survey (KNHANES).

METHODS

A total of 4504 individuals aged ≥55 years with comprehensive data including meal frequency and fundus photography were selected using the KNHANES 2015-2018 database. Participants were divided into 2 groups based on breakfast frequency per week; intermittent fasting (nearly 0 time/week) and nonfasting (5-7 times/week) groups. Multiple logistic regression analysis was performed to determine the risk factors for AMD identified by fundus photography.

RESULTS

AMD was identified in 25.1% of total participants. The intermittent fasting group had a decreased risk of AMD compared with the nonfasting group (adjusted odds ratio [aOR] 0.413, 95% CI 0.203-0.841), especially in individuals with a younger age (<70 years, aOR 0.357, 95% CI 0.153-0.833), obesity (aOR 0.663, 95% CI 0.424-1.037), and urban residence (aOR 0.437, 95% CI 0.248-0.769). Increased age (aOR 1.058, 95% CI 1.041-1.076) and serum high-density lipoprotein levels (aOR 1.011, 95% CI 1.002-1.021) were also independent risk factors for AMD.

CONCLUSIONS

Using the population-based survey data, we demonstrated that intermittent fasting by skipping breakfast was significantly associated with a reduced risk of AMD in a representative older adult population, especially in individuals with age <70 years, obesity, and urban residence.

COVID-19 Morbidity and Severity in Patients With Age-Related Macular Degeneration: A Korean Nationwide Cohort Study

Purpose

To determine the potential association between age-related macular degeneration (AMD), a representative chronic age-related degenerative disease of the retina associated with inflammation and aging, and susceptibility to SARS-CoV-2 infection and severe COVID-19 outcomes.

Design

Nationwide cohort study with propensity-score matching.

Methods

A population-based nationwide cohort in Korea was examined. Data were obtained from the Health Insurance Review & Assessment Service of Korea, including all patients aged ≥40 years who underwent SARS-CoV-2 testing in South Korea between January 1, 2020 and May 15, 2020 (excluding self-referral). The primary outcome was SARS-CoV-2 test positivity and the secondary outcome was severe clinical outcome of COVID-19.

Results

The unmatched cohort consisted of 135,435 patients who were tested for SARS-CoV-2: 4531 patients (3.3%) tested positive for SARS-CoV-2 and 5493 (4.1%) had AMD. After propensity score matching, exudative AMD was associated with an increased likelihood of susceptibility to SARS-CoV-2 infection (adjusted odds ratio [aOR], 1.50; 95% confidence interval [CI], 1.03-2.25), and a considerably greater risk of severe clinical outcomes of COVID-19 (aOR, 2.26; 95% CI, 1.02-5.26), but not any AMD and non-exudative AMD.

Conclusions

In a Korean nationwide cohort, data suggest that clinicians should be aware of the greater risk of susceptibility to severe clinical outcomes of COVID-19 in patients with exudative AMD. These findings provide an improved understanding of the relationship between the pathogenesis of COVID-19 and chronic neurological disorders.

Association of Physical Activity With Primary Cardiac Arrest Risk in the General Population: A Nationwide Cohort Study of the Dose-Response Relationship

OBJECTIVE

To quantify the dose-response relationship between moderate to vigorous physical activity and primary cardiac arrest (PCA).

PATIENTS AND METHODS

There were 504,840 participants older than 18 years who underwent the Korean National Health Screening Program, including a self-administered questionnaire for physical activity from January 1, 2009, through December 31, 2014. Physical activity levels were converted into metabolic equivalent tasks (METs) per week and categorized to correspond with multiples of public health recommendations. We evaluated the quantitative and categorical dose-response relationship between physical activity and PCA.

RESULTS

A curvilinear dose-response relationship between physical activity and PCA was observed; the benefits started at two-thirds (5 MET-hour/week) of the United States and World Health Organization guidelines-recommended minimum (7.5 MET-hour/week) and continued to 5 times (40 MET-hour/week) the recommended minimum (P nonlinearity <.001). The largest benefit was noted at a level of 2 to 3 times the recommended minimum (hazard ratio, 0.6; 95% CI, 0.4 to 0.8). In addition, there was no evidence of an increased PCA risk at a level more than 5 times the recommended minimum (hazard ratio, 0.7; 95% CI, 0.5 to 1.1). These associations were consistent regardless of age, sex, body mass index, comorbid conditions, and estimated 10-year risk for cardiovascular disease.

CONCLUSION

The beneficial effect of physical activity on PCA started at two-thirds of the recommended minimum and continued to 5 times the recommended minimum. No excess risk for PCA was present among individuals with activity levels more than 5 times the recommended minimum regardless of cardiovascular disease or lifestyle risk factor presence.

Age-Related Macular Degeneration: What Do We Know So Far?

Ageing is a natural process that everyone experiences and nobody is an exception. With ageing, our body experiences physiological changes. In this article, the focus is made on the physiological changes of our eyes related to ageing and age-related macular degeneration (AMD), which is the most common cause of incurable visual impairment in developed countries. With ageing populations increasing in many countries, more and more patients will have AMD in a foreseeable future. In Eastern Europe, blindness due to AMD, currently, is approximately 20% and there has been an increasing trend depicted in the future. Generally, AMD can be divided into early stages and two forms in an advanced (late) stage. Advanced AMD form includes neovascular AMD (wet) and geographic atrophy (late dry), both of these are associated with substantial, progressive visual impairment. The pathogenesis of AMD is complex and, by far, not completely understood. Multiple factors have been studied, for example: environmental factor, genetic factor (complement factor H), lifestyle. It has been proved that they are linked to higher the risk of developing of AMD, however, the actual pathogenesis is not yet formulated. AMD progression can also be a culprit to certain biochemical events and molecular changes linked to inflammation and pathological angiogenesis. In nowadays, we do have diagnostic methods for both early and late forms of AMD as well as ways to prevent progression of early AMD and wet AMD. However, until now, there is still no treatment for dry AMD. This article is a brief review of AMD and may hopefully lead to some future directions in early diagnostic methods and treating dry AMD.

Metabolic Syndrome and Risk of Lung Cancer: An Analysis of Korean National Health Insurance Corporation Database

INTRODUCTION

Metabolic syndrome is known to increase the risk of several cancers. However, the association between lung cancer and metabolic syndrome remains unclear. Thus, we investigated the impact of metabolic syndrome on the incidence of lung cancer.

METHODS

This study enrolled participants in a health screening program provided by the Korean National Health Insurance Service between January 2009 and December 2012. The incidence of lung cancer was observed until December 2016. We analyzed the risk of lung cancer according to the presence of metabolic syndrome, metabolic syndrome components, and number of metabolic syndrome components.

RESULTS

During the study, 45 635 new cases of lung cancer were recorded among 9 586 753 participants. The presence of metabolic syndrome and all its components was positively associated with the risk of lung cancer in men after multivariate adjustment (hazard ratio [HR] of metabolic syndrome 1.15; 95% confidence interval [CI], 1.12-1.18). The risk of lung cancer increased with the number of components present. The effect of metabolic syndrome on the increasing risk of lung cancer is may be higher in underweight male ever-smokers than in other participants.

CONCLUSION

Metabolic syndrome was associated with an increased risk of lung cancer in men. Moreover, the higher the number of metabolic syndrome components, the higher the risk of lung cancer.

Big Data in Ophthalmology

Big data is the fuel of mankind's fourth industrial revolution. Coupled with new technology such as artificial intelligence and deep learning, the potential of big data is poised to be harnessed to its maximal in years to come. In ophthalmology, given the data-intensive nature of this specialty, big data will similarly play an important role. Electronic medical records, administrative and health insurance databases, mega national biobanks, crowd source data from mobile applications and social media, and international epidemiology consortia are emerging forms of "big data" in ophthalmology. In this review, we discuss the characteristics of big data, its potential applications in ophthalmology, and the challenges in leveraging and using these data. Importantly, in the next phase of work, it will be pertinent to further translate "big data" findings into real-world applications, to improve quality of eye care, and cost-effectiveness and efficiency of health services in ophthalmology.

Voluntary Exercise Suppresses Choroidal Neovascularization in Mice

Purpose

To determine the effect of voluntary exercise on choroidal neovascularization (CNV) in mice.

Methods

Age-matched wild-type C57BL/6J mice were housed in cages equipped with or without running wheels. After four weeks of voluntary running or sedentariness, mice were subjected to laser injury to induce CNV. After surgical recovery, mice were placed back in cages with or without exercise wheels for seven days. CNV lesion volumes were measured by confocal microscopy. The effect of wheel running only in the seven days after injury was also evaluated. Macrophage abundance and cytokine expression were quantified.

Results

In the first study, exercise-trained mice exhibited a 45% reduction in CNV volume compared to sedentary mice. In the replication study, a 32% reduction in CNV volume in exercise-trained mice was observed (P = 0.029). Combining these two studies, voluntary exercise was found to reduce CNV by 41% (P = 0.0005). Exercise-trained male and female mice had similar CNV volumes (P = 0.99). The daily running distance did not correlate with CNV lesion size. Exercise only after the laser injury without a preconditioning period did not reduce CNV size (P = 0.41). CNV lesions of exercise-trained mice also exhibited significantly lower F4/80+ macrophage staining and Vegfa and Ccl2 mRNA expression.

Conclusions

These findings provide the first experimental evidence that voluntary exercise improves CNV outcomes. These studies indicate that exercise before laser treatment is required to improve CNV outcomes.

Impact of visual impairment on physical activity in early and late age-related macular degeneration

BACKGROUND

Modifiable risk factors for age-related macular degeneration (AMD) include smoking, nutrition and likely physical activity (PA). Levels of PA, however, are impacted by any visual impairment which makes the assessment of any association with AMD difficult.

PURPOSE

To assess the impact of visual impairment under both high and low luminance conditions on levels of PA in early and late AMD.

METHODS

Ninety participants with early to late AMD underwent a clinical assessment including conventional best-corrected visual acuity, low luminance visual acuity, contrast sensitivity and the Moorfields acuity test. PA was recorded using a wrist-worn accelerometer (GENEActiv, Activeinsights) on seven consecutive days. Patient characteristics were compared with the Wilcoxon rank-sum test and determinants of moderate-to-vigorous-PA (MVPA) were assessed using linear regression models.

RESULTS

Mean age was 73.9 ± 8.5 years (range 50-89) and 47 subjects (52.2%) were women. Average MVPA time was longer in the early (355.1 ± 252.0 minutes/week) compared to the late AMD group (162.2 ± 134.6 minutes/week; p<0.001). Using linear regression, age [β = -0.25; 95% confidence interval (CI): -12.9; -0.8, p = 0.028] and AMD stage (β = -0.28; 95% CI: -230.9, -25.0; p = 0.015) but not visual impairment on any of the employed tests were associated with MVPA (minutes/week).

CONCLUSIONS

We found late AMD to be associated with reduced PA. As performance on any of the visual tests was not associated with PA, this association cannot entirely be explained by functional impairment. More research is needed to further explore the association of PA and AMD as PA may be a potentially modifiable risk factor.

Physical Activity and Risk of Atrial Fibrillation: A Nationwide Cohort Study in General Population

Although exercise prevents cardiovascular disease and mortality, vigorous exercise and endurance athletics can cause atrial fibrillation (AF). However, no large cohort study has assessed the relationship between physical activity and AF in the general population. We assessed the effect of physical activity at different energy expenditures on the incidence of AF. We studied 501,690 individuals without pre-existing AF (mean age, 47.6 ± 14.3 years; 250,664 women [50.0%]) included in the Korean National Health Insurance Service database. The physical activity level was assessed using a standardized self-reported questionnaire at baseline. During a median follow-up of 4 years, 3,443 participants (1,432 women [41.6%]) developed AF. The overall incidence of AF at follow-up was 1.79 per 1,000 person-years. The subjects who met the recommended physical activity level (500–1,000 metabolic equivalent task [MET] minutes/week) had a 12% decreased AF risk (adjusted hazard ratio [HR]: 0.88, 95% confidence interval [CI]: 0.80–0.97), but not the insufficiently (1–500 MET-minutes/week; HR: 0.94, 95% CI: 0.86–1.03) and highly active subjects (≥1,000 MET-minutes/week; HR: 0.93, 95% CI: 0.85–1.03). The recommended minimum key target range of physical activity level was associated with the maximum benefit for reduced AF risk in the general population. The dose-response relationship between physical activity level and AF risk showed a U-shaped pattern. Although exceeding the key target range attenuated this benefit, it did not increase the AF risk beyond that during inactivity.

Physical activity and eye diseases. The Beijing Eye Study

PURPOSE

To assess associations between the amount of physical activity and the prevalence of ocular diseases.

METHODS

The participants of the population-based Beijing Eye Study underwent a detailed ophthalmological examination and an interview. Physical activity was assessed in a standardized questionnaire.

RESULTS

Out of 3468 study participants, information on their physical activity was available for 3031 (87.4%) individuals (age: 64.6 ± 9.7 years; range: 50-93 years). In multivariate analysis (regression coefficient r: 0.41), higher physical activity was associated with a lower prevalence of diabetic retinopathy [p = 0.009; standardized regression coefficient beta: -0.05; non-standardized regression coefficient B: -15.7; 95% confidence interval (CI): -27.6, -3.90] after adjusting for younger age, rural region of habitation, lower level of education, lower blood concentrations of triglycerides and low-density lipoproteins and higher blood concentrations of high-density lipoproteins, higher systolic blood pressure, lower body mass index and lower depression score. Other major ocular diseases such as open-angle glaucoma (p = 0.25), angle-closure glaucoma (p = 0.59), nuclear cataract (p = 0.78), cortical cataract (p = 0.54), posterior subcapsular cataract (p = 0.96), retinal vein occlusions (p = 0.93) and central serous choroidopathy (p = 0.39) were not statistically associated with physical activity in that model. The association between higher physical activity and prevalence of age-related macular degeneration (p = 0.04; β: 0.04; B: 4.87; 95% CI: 0.25, 9.50) was marginally significant.

CONCLUSIONS

Higher physical activity and less sedentary lifestyle were associated with a lower prevalence of diabetic retinopathy, while the occurrence of other major ocular diseases such as any type of cataract and of glaucoma, retinal vein occlusions and central serous choroidopathy was statistically independent of physical activity or a more sedentary lifestyle.