Skövde Cataract Study

Famine exposure in early life increases risk of cataracts in elderly stage

Background

Epidemiological studies have shown that early-life nutritional deficiencies are associated with an increased risk of diseases later in life. This study aimed to explore the correlation between famine exposure during the early stages of life and cataracts.

Methods

We included 5,931 participants from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 2018 cross-sectional data in our study. Subjects were categorized into three groups by their age during the famine: adulthood group, school age famine exposure group, and teenage famine exposure group. Utilizing binary logistic regression models, we investigated the relationship between early-life famine exposure and cataracts.

Results

Compared to the adulthood group, both the school age exposure group (OR = 2.49, 95%CI = 1.89-3.27) and teenage exposure group (OR = 1.45, 95%CI = 1.20-1.76) had a heightened risk of developing cataracts in elderly stage. And the sex differences in the impact of famine during early years on elderly cataract risk were observed, particularly indicating a higher risk among women who experienced childhood famine compared to men with similar exposure.

Conclusion

Famine exposure during the early stages of life is associated with a heightened risk of developing cataracts in old age. To prevent cataracts in elderly individuals, particularly in females, measures should be taken to address nutritional deficiencies in these specific periods.

Pseudophakia and Lens Opacities in 70-Year-Olds in Gothenburg, Sweden; Gender Differences, Impact on Self-Reported Visual Function and Validation of Self-Reported Cataract and Pseudophakia

Purpose

The study aimed at determining the prevalence and sex differences in cataract, pseudophakia, lens opacities and self-reported cataract in 70-year-old people in Gothenburg, Sweden. The purpose was also to identify correlations between lens opacities, visual acuity and subjective visual function, and to validate self-reported cataract and cataract surgery.

Patients and Methods

Population-based cross-sectional study where participants (n=1182) answered questions about self-reported diagnosis of cataract and cataract surgery. A total of 1139 subjects completed the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25), 560 subjects underwent ophthalmic examination including visual acuity and lens photography. t-test, Pearson chi-square and Mann-Whitney U-test were used for obtaining p-values. ANOVA (analysis of variances, Kruskal-Wallis, one-way) was used to compare VFQ-25 between 3 groups; no cataract, cataract and pseudophakia. To clarify the differences between specific pairs of groups post-hoc test (Bonferroni) was used after ANOVA.

Results

Self-reported cataract was more common in women than in men (27.2% vs 19.1%, p=0.001, chi-square). Cataract surgery was reported by 16.3% of women and 12.6% of men (p=0.072). Upon eye examination, the prevalence of pseudophakia was 16.9% in women compared to 10.2% in men (p=0.020). The prevalence of cataract, including pseudophakia, was 31.9% in women versus 23.8% in men (p=0.033). Significant correlations (Spearman's rho) were found between lens opacities and visual acuity. Self-reported cataract surgery showed a very high specificity and high sensitivity. The composite score from NEI VFQ-25 was lower in people with pseudophakia than in people with/without cataract (p=0.012, Kruskal-Wallis).

Conclusion

The prevalence of cataract including pseudophakia in 70-year-olds in Gothenburg is higher compared to previous studies in similar geographical areas. Also, it is more common in women than in men. The lack of significant sex differences in lens opacities may be due to cataract surgery at an earlier stage. Validation showed very good agreement between pseudophakia and self-reported cataract surgery.

Outcome of cataract surgery in eyes with diabetic retinopathy: a Swedish national cataract register report

PURPOSE

To analyse if patients with diabetic retinopathy (DR) subjected to cataract surgery differ in outcome compared to patients without DR with regard to best-corrected visual acuity (BCVA), deviation from target refraction, intraoperative difficulties and risk of complications.

METHODS

A register-based study from the Swedish National Cataract Register (NCR) during the years 2015-2017 including 358 040 cataract procedures. Patients with other ocular pathology than cataract and DR were omitted from outcome analyses.

RESULTS

Diabetic retinopathy was reported in 13 724 of all eyes (3.8%). Preoperative BCVA was significantly worse in DR patients than in patients without DR, 0.54 ± 0.33 compared to 0.40 ± 0.27 (logMAR, mean ± SD, p < 0.001). The same was evident for postoperative BCVA, 0.15 ± 0.25 for DR patients versus 0.06 ± 0.13 (p < 0.001). The improvement in BCVA was slightly better in DR than in non-DR, -0.40 ± 0.32 (logMAR; mean ± SD) versus -0.35 ± 0.27, p < 0.001. The absolute mean biometry prediction error was 0.42 ± 0.50 diopters (D) in DR and 0.43 ± 0.71 D in non-DR patients, p = 0.768. One or more intraoperative difficulties, including mechanical pupil dilation, capsular stain, hooks at capsulorhexis margin or capsular tension ring, had an adjusted odds ratio (OR) of 1.75 (95% confidence interval [CI] 1.61-1.90, p < 0.001) in DR versus non-DR cases and the rate of posterior capsular tears (PCR) had an adjusted OR of 1.76 (95% CI 1.40-2.20, p < 0.001).

CONCLUSION

Eyes with DR have inferior pre- and postoperative BCVA compared to non-DR eyes. There is little difference in improvement of BCVA and no difference in absolute mean biometry prediction error. Importantly, intraoperative difficulties and PCRs are almost twice as common in DR patients, strongly indicating that these patients should be managed by experienced surgeons.

Prevalence and risk factors for age-related cataract in Sweden

BACKGROUND

Cataract is a major cause of visual impairment worldwide. There is a paucity of prevalence studies from Sweden. Therefore, we report the prevalence of cataract and its risk factors in a population-based study of older adults in Sweden.

METHODS

The Tierp Glaucoma Survey was conducted in the municipality of Tierp, Sweden, including 760 subjects aged 65-74 years. The presence of cataract was determined based on retroillumination, with lens opacities evident on slit-lamp examination. To assess risk factors for cataract, odds ratios (ORs) were calculated, adjusted for age and gender.

RESULTS

A total of 234 individuals were found to have cataract, 12 of whom had undergone cataract surgery. The prevalence adjusted for nonparticipation was 31.5% (95% confidence interval [CI] 29.4-33.6), 35.2% (95% CI 28.7-41.8) in females and 26.2% (95% CI 19.8-32.6) in males. Cataract was associated with age ≥70 years (OR 1.93; 95% CI 1.41-2.64), female gender (OR 1.54; 95% CI 1.12-2.11), and myopia (OR 2.3; 95% CI 1.16-3.56), while pseudoexfoliation, smoking, diabetes, hypertension, and ischaemic heart disease were not.

CONCLUSION

Nearly one-third of the sample were estimated to have lens opacities, or had undergone cataract surgery, making cataract a frequent disorder of older age. The study provided further evidence that increasing age, female gender, and myopia are associated with cataract.

Vision-related quality of life and visual function in a 70-year-old Swedish population

PURPOSE

To investigate vision-related quality of life (VRQoL), visual function and predictors of poor vision in a population of 70-year-olds.

METHODS

Self-reported ocular morbidity and responses to the National Eye Institute Visual Functioning Questionnaire-25 (NEI VFQ-25) in a cross-sectional population study (N = 1203) in Gothenburg, Sweden, were compared with results from ophthalmic examination (N = 560).

RESULTS

The most common self-reported ophthalmic morbidities were cataract (23.4%), age-related macular degeneration (AMD; 4.7%), glaucoma (4.3%) and diabetic retinopathy (1.4%). Cataract was more prevalent in women (p = 0.001). The composite score from NEI VFQ-25 for the entire cohort was 91.4 (standard deviation: 27.5). When comparing composite score for different eye diseases, persons with cataract or AMD exhibited lower scores (p = 0.029 and 0.018, respectively). Best-corrected visual acuity (BCVA) was normal (≥0.5 decimal) in 98.9%; two individuals had low vision (<0.3). Men exhibited better BCVA (median: -0.08 logMAR) than women (-0.06; p = 0.005). Visual field defects were observed in 16.3% and uncorrected refractive errors in 61.5%. Poor vision was reported by 7.4% of participants with presenting visual acuity (PVA) ≥0.5 (decimal), while 66.7% with PVA <0.5 reported good vision. Of 27 individuals with PVA <0.5, 55.6% obtained a BCVA of ≥1.0 with the right correction. Low contrast sensitivity was a significant predictor of experiencing poor vision (p = 0.008), while PVA and visual field defects were not.

CONCLUSIONS

Low contrast sensitivity is a predictor of experiencing poor vision. There is a discrepancy between subjective/objective visual function and a high prevalence of uncorrected refractive errors. Women have more cataract, and men demonstrate slightly better visual acuity.

Global and regional prevalence of age-related cataract: a comprehensive systematic review and meta-analysis

The aim of our study was to estimate regional and global cataract prevalence, its prevalence in different age groups, and the determinants of heterogeneity and its prevalence. For that, we used international databases such as PubMed, Web of Science, Scopus, Embase, and other sources of information to conduct a systematic search for all articles concerning the prevalence of age-related cataract and its types in different age groups. Of the 9922 identified articles, 45 studies with a sample size of 161,947 were included in the analysis, and most of them were from the Office for the Western Pacific Region (19 studies). Age- standardized pooled prevalence estimate (ASPPE) and 95% confidence interval (95% CI) of any cataract, cortical cataract, nuclear cataract, and posterior subcapsular (PSC) cataract were 17.20% (13.39-21.01), 8.05% (4.79-11.31), 8.22% (4.93-11.52), and 2.24% (1.41-3.07), respectively. Significant effects on heterogeneity were observed for the WHO region in the prevalence of any cataract (b: 6.30; p: 0.005) and study year in the prevalence of nuclear cataract (b: -0.66, p: 0.042). In general, the prevalence of cataract not only varies by region but also by age group, and most cases are over the age of 60 years. We examined the sources of variance in the prevalence of cataract and its different types, and identified age as a responsible factor in the prevalence of any cataract, cortical cataract, nuclear cataract, and PSC of cataract, WHO region in the prevalence of any cataract, and study year in the prevalence of nuclear cataract.

The Gender-Dependent Association between Obesity and Age-Related Cataracts in Middle-Aged Korean Adults

The aim of this study was to investigate the association of central and abdominal obesity with the prevalence of cataracts in a middle-aged Korean population. This retrospective cross-sectional study was based on the data collected from the Korea National Health and Nutrition Examination Survey 2008–2009, in which 4,914 subjects were examined. Ophthalmological examinations were performed to determine the presence of a nuclear, cortical, or posterior subcapsular cataract. Both general obesity (a body mass index ≥25 kg/m²) and abdominal obesity (a waist circumference ≥90 cm for men and ≥80 cm for women) were significantly associated with the occurrence of cataracts among middle-aged women [adjusted odds ratio (aOR), 1.32; 95% confidence interval (CI), 1.03–1.69; and aOR, 1.40; 95% CI, 1.06–1.85, respectively], while abdominal obesity was significantly inversely associated with the occurrence of cataracts among middle-aged men (aOR, 0.76; 95% CI, 0.58–1.01; and aOR, 0.66; 95% CI, 0.49–0.89, respectively). We report a difference in the association between obesity and the prevalence of cataracts based on gender.

Gender and cataract--the role of estrogen

There is evidence from epidemiologic data that cataract is more common in women than men. This is not solely due to a higher rate of cataract extraction in women, as is the case in the western world, but several population-based studies show that females have a higher prevalence of lens opacities, especially cortical. There is no firm evidence that lifestyle-related factors are the cause of this gender discrepancy. Focus has therefore been directed towards the role of estrogen in cataract formation. Although data on endogenous and exogenous estrogen involvement in cataractogenesis are conflicting, some studies have indicated that hormone therapy may decrease the risk of cataract and thus be protective. It has been hypothesized that the decrease in estrogen at menopause cause increased risk of cataract in women, i.e. not strictly the concentration of estrogen, but more the withdrawal effect. Estrogens are known to exert several anti-aging effects that may explain the longer lifespan in women, including metabolically beneficial effects, neuroprotection, preservation of telomeres and anti-oxidative properties. Since oxidative stress is considered important in cataractogenesis, studies have investigated the effects of estrogens on lens epithelial cells in culture or in animal models. Several investigators have found protection by physiological concentrations of 17β-estradiol against oxidative stress induced by H2O2 in cultured lens epithelial cells. Although both main types of estrogen receptors, ERα and ERβ, have been demonstrated in lens epithelium, most studies so far indicate that the estrogen-mediated protection in the lens is exerted through non-genomic, i.e. receptor-independent mechanisms, possibly through phosphorylation of extracellular signal-regulated kinase (ERK1/ERK2), a member of the mitogen-activated protein kinase (MAPK)-signaling pathway. Further studies are needed, both epidemiologic as to the role of hormone therapies, and laboratory studies regarding molecular estrogen-mediated mechanisms, in order to comprehend the role of estrogens on cataract formation.

Prevalence of major eye diseases and causes of visual impairment in the adult Finnish population: a nationwide population-based survey

PURPOSE

To estimate the prevalence of cataract, glaucoma, age-related maculopathy (ARM) and diabetic retinopathy (DR) in the adult Finnish population.

METHODS

A representative cross-sectional sample of the Finnish population aged 30 years and older. Of the 7979 eligible people, 7413 (93%) were interviewed and/or examined. The interview included self-reported doctor-made diagnoses of cataract, glaucoma, degenerative fundus changes (mainly ARM) or DR. Information on self-reported eye diseases was complemented with data from national registers, and case records were gathered for non-participants and persons with visual acuity (VA) < 0.5 or reporting difficulties in vision or eye diseases without assessed VA.

RESULTS

Based on self-reported and/or register-based data the estimated total prevalences of cataract, glaucoma, ARM and DR in the study population were 10%, 5%, 4% and 1%, respectively. All these chronic eye diseases increased with age (p < 0.001). The corresponding prevalences for persons aged 65 and older were 34%, 13%, 12% and 2%, respectively. Cataract and glaucoma were more common in women than in men [odds ratio (OR) 1.55, 95% confidence interval (CI) 1.26-1.91; OR 1.57, 95% CI 1.24-1.98, respectively]. The most prevalent eye diseases in people with visual impairment (VA < or = 0.25) were ARM (37%), unoperated cataract (27%), glaucoma (22%) and DR (7%).

CONCLUSION

The high prevalence of these mainly age-related eye diseases, together with increasing life expectancy, mean that continuous efforts are needed to identify and treat eye diseases in order to maintain patients' quality of life and to alleviate the social and economic burden of serious eye diseases.

The prevalence of lens opacities in Tehran: the Tehran Eye Study

PURPOSE

To determine the prevalence of lens opacities and cataract surgical coverage among Tehran citizens 40 years of age and older.

METHODS

The Tehran Eye Study was a population-based survey, with random sampling from Tehran household clusters. Those 40 years of age and older from that survey were included in this analysis. All participants underwent full optometric, slit lamp, and fundoscopic examinations. Lens opacity was assessed after pupil dilation using the modified Lens Opacities Classification System III (LOCS III). The main indices for prevalence of cataract were any lens changes, defined as the presence of a gradable cataract in one or both eyes, and all lens changes, defined as any lens changes plus a history of cataract surgery.

RESULTS

A total of 1434 participants were included in this analysis; 305 of which met the criteria for all lens changes resulting in an adjusted prevalence of 22.7% (CI95%: 20.2%-25.3%). The prevalence was 21.2% among men and 24.5% among women. The prevalence of any lens changes was 19.1% (CI95%: 16.6%-21.6%) and the prevalence was higher in women. The prevalence for both indices increased with age. Considering their better eyes, 39 people (2.7%) were shown to have low vision because of cataract and another 12 (0.8%) were classified as blind.

CONCLUSIONS

Cataract has affected approximately one-fifth of the Tehran population aged 40 years and over, women more than men, and has severely affected the vision of approximately 3.5% of this population. We found that access to cataract surgery facilities was not an issue.

The Pyhäjärvi Cataract Study. I. Study design, baseline characteristics and the demand for cataract surgery

PURPOSE

The Pyhäjärvi Cataract Study aims to study demand for cataract surgery in the population of a rural town in Finland.

METHODS

A random, population-based sample of 881 persons aged > or = 60 years were interviewed by telephone to obtain a Visual Function-14 (VF-14) score. A total of 294 persons were invited for an ophthalmic examination based on three categories of VF-14 score. Of these, 230 (78%) responded, 10 of whom were excluded as a result of prior bilateral surgery. The New Zealand Priority Criteria (NZPC) and the 15-Dimension Quality of Life (15-D) instruments were administered. In addition, another group of 96 patients waiting for cataract surgery were examined and scored using the VF-14, NZPC and 15-D instruments. A modified Lens Opacities Classification System (LOCS) III classification was used for grading the cataract.

RESULTS

Only one (0.5%) of the 220 examined subjects was referred for cataract surgery. Many patients with relatively good visual acuity (VA), including six people with a 100-point VF-14 score suggesting no visual symptoms, were waiting for surgery. Demographic factors were not associated with access to cataract surgery. The patients examined from the waiting list for cataract surgery had more cataractous changes in the lens(es), poorer VA, were older, and scored higher on the NZPC instrument than the population sample examined.

CONCLUSIONS

Practically no hidden demand for cataract surgery was found in the study population as defined by the national criteria for cataract surgery in Finland. This reflects the fact that the current Finnish health care system appears to recognize and treat cataract patients very well, even in rural areas. Although VA tests may not be sufficient for evaluating need for cataract surgery, the role of questionnaires is not clear either.