Effects of Cataract Surgery on Melatonin Secretion in Adults 60 Years and Older: A Randomized Clinical Trial.

Importance: Cataract surgery, which increases perception of light, may increase melatonin secretion. Melatonin secretion has been associated with depression, diabetes, cognitive impairment, and breast cancer. To date, no evidence from a randomized clinical trial exists to support this cataract surgery hypothesis. Objective: To determine whether cataract surgery modifies the melatonin secretion at 3 months after cataract surgery in 169 adult patients. Design, Setting, and Participants: A parallel-group randomized clinical trial was conducted at a single referral center from July 1, 2014, to June 30, 2017. Data were analyzed from January 1, 2018, to March 31, 2019. Patients were aged 60 years or older, had no history of cataract surgery, and had cataracts with grade 2 or higher nuclear opacifications based on the Lens Opacities Classification System III. Analyses were based on intention to treat. Interventions: Patients were randomized 1:1:1:1 to receive cataract surgery using artificial clear intraocular lens (IOL) or yellow IOL. Group 1 received prompt surgery with clear IOL, group 2, prompt surgery with yellow IOL, group 3, delayed surgery with clear IOL, and group 4, delayed surgery with yellow IOL. The intervention group consisted of groups 1 and 2, and the control group consisted of groups 3 and 4. Main Outcomes and Measures: Urinary melatonin excretion in the intervention group was measured at 3 months after surgery, and urinary melatonin excretion in the control group was measured before delayed surgery. Results: Of the 169 randomized patients, 97 were men (57.4%). The mean (SD) age was 75.7 (6.7) years. Mean urinary melatonin excretion was calculated as standardized urinary concentration, the ratio of urinary concentration to urinary creatinine concentration (nanograms per milligram of creatinine), in the intervention group after cataract surgery. Mean urinary melatonin excretion was significantly higher than in the control group (adjusted mean difference of creatinine concentration, 0.159 log ng/mg, 95% CI, 0.045-0.273; P = .007) independent of baseline urinary melatonin excretion and potential confounders. Subgroup analysis comparing group 1 with group 3 revealed that concentration of urinary melatonin excretion in patients who received clear IOLs was higher than the control group by creatinine concentration 0.212 log ng/mg (95% CI of the difference, 0.058-0.365; P = .008). However, the difference between patients in group 2 and group 4 was not significant (adjusted mean difference for creatinine excretion, 0.083 log ng/mg, 95% CI, -0.087 to 0.253; P = .33). The difference of concentration of mean urinary melatonin excretion between patients in group 1 and those in group 2 was not significant (95% CI of the difference for creatinine concentration, -0.19 to 0.40 log ng/mg; P = .48). Conclusions and Relevance: The findings in this study support the hypothesis that cataract surgery increases melatonin secretion. The effect of clear IOLs vs yellow IOLs on these outcomes was not shown to be different. Trial Registration: UMIN-CTR Identifier: UMIN000014559.

Congenital cataract in newborns: A qualitative study on parents' experiences of the surgery and subsequent care.

PURPOSE: Having a child with congenital cataract that requires surgery, contact lens treatment, and frequent medication is a life-altering experience. The aim of this study was to provide more in-depth knowledge of parents' experiences of diagnosis, surgery, and subsequent care, in order to find the areas for improvement. METHODS: Data were collected via semi-structured interviews with parents recruited from St. Erik Eye Hospital, Sweden. The children were operated for congenital cataract before 3 months of age and were aged 12-24 months at the time of the interviews. The interviews were analysed using qualitative content analysis with an inductive approach. RESULTS: Three themes emerged from the data: living in a turbulent time before the diagnosis, coping during the time of initial treatment, and managing the responsibility of their child's visual development. All parents expressed confidence in the operating unit. However, there was a clear need for reliable information on the condition, the surgery, and likely the long-term outcome in the time between receiving the preliminary diagnosis at the maternity ward and getting it confirmed by a paediatric ophthalmologist. CONCLUSION: Much of the parents' concern in this turbulent time is linked to poor information before the visit to the eye hospital. We, therefore, recommend earlier contact with the eye hospital, preferably at the time of writing the referral. Moreover, the possibility of providing up-to-date information via alternative information channels such as smartphone apps should be investigated.

Association between cataract and cotinine-verified smoking status in 11 435 Korean adults using Korea National Health and Nutrition Examination Survey data from 2008 to 2016.

PURPOSE: To investigate the association between cataract and cotinine-verified smoking status. SETTING: Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, South Korea. DESIGN: Retrospective study. METHODS: Participants were randomly selected using data collected by the Korea National Health and Nutrition Examination Survey from 2008 to 2016. Participants completed a questionnaire to self-report smoking status and a history of cataract, among other variables. To identify the relationship between cataract and smoking, a new variable was used to define smoking status, survey-cotinine-verified smoking status (SCS)-the combination of self-reported smoking status and cotinine-verified smoking status- and thus identify hidden smokers. RESULTS: In total, 11 435 participants were eligible for final analysis. The study comprised 4925 men and 6510 women; the mean age was 52.86 ± 16.83 years (median: 54 years). Of 2292 SCS smokers, 382 (16.7%) were nonsmokers according to their self-report. Notably, the ratio of the cotinine-verified to self-reported smoking rate of women was greater than that of men, 1.60 and 1.06, respectively. This indicated that female hidden smokers may affect the results of studies based on self-reported questionnaires. Multivariate logistic regression analysis showed that smoking was correlated with cataract (odds ratio [OR], 1.37 [95% CI, 1.07-1.76]; OR, 1.35 [CI, 1.12-1.64]; and OR, 1.36 [CI, 1.10-1.69]) for self-reported, cotinine-verified, and SCS, respectively. No statistically significant sex difference was found. CONCLUSION: Smoking was associated with cataract, but it did not vary by sex. Female hidden smoking must be considered when investigating the association between smoking and cataract based on self-reported questionnaires.

Cadmium and lead exposure and risk of cataract surgery in U.S. adults.

Cataract is a major cause of visual dysfunction and the leading cause of blindness. Elevated levels of cadmium and lead have been found in the lenses of cataract patients, suggesting these metals may play a role in cataract risk. This study aimed to examine the associations of blood lead, blood cadmium and urinary cadmium with cataract risk. We identified 9763 individuals aged 50 years and older with blood lead and cadmium levels, and a randomly selected subgroup of 3175 individuals with available urinary cadmium levels, from the National Health and Nutrition Examination Surveys (NHANES) from 1999 to 2008 (mean age=63years). Participants were considered to have cataract if they self-reported prior cataract surgery in NHANES's vision examination. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed using survey logistic regression models. We identified 1737 cataract surgery cases (the weighted prevalence=14.1%). With adjustment for age, race/ethnicity, gender, education, diabetes mellitus, body mass index, cigarette smoking (serum cotinine and pack-years) and urine hydration, every 2-fold increase in urinary cadmium was associated with a 23% higher risk of cataract surgery (OR=1.23, 95% CI: 1.04, 1.46, p=0.021). We found no associations of cataract surgery with blood cadmium (OR=0.97, 95% CI: 0.89, 1.07) and blood lead (OR=0.97, 95% CI: 0.88, 1.06). Mediation analysis showed that for the smoking-cadmium-cataract pathway, the ratio of smoking's indirect effect to the total effect through cadmium was more than 50%. These results suggest that cumulative cadmium exposure may be an important under-recognized risk factor for cataract. However, these findings should be interpreted with a caution because of inconsistent results between urinary cadmium and blood cadmium.

Sodium Intake and Socioeconomic Status as Risk Factors for Development of Age-Related Cataracts: The Korea National Health and Nutrition Examination Survey.

PURPOSE: Cataract is a very prevalent ocular disorder, and environmental risk factors for age-related cataracts have been widely investigated. We aimed to evaluate an association of dietary sodium intake and socioeconomic factors with the development of age-related cataracts. METHODS: A cross-sectional case-control study based on the 2008-2011 Korea National Health and Nutrition Examination Survey. Dietary sodium intake was estimated using urinary sodium to creatinine ratio (U[Na+]/Cr). RESULTS: Among a total 12,693 participants, 2,687 (21.1%) had cataracts and 10,006 patients without cataracts served as controls. The prevalence of cataracts increased with age and quartiles of U[Na+]/Cr (p for trend < 0.001). Multivariate logistic regression analyses revealed that factors related to the development of cataracts were age ≥ 50 years (adjusted odds ratio [aOR] 15.34, 95% confidence interval [CI] 13.31‒17.69), low income (aOR 1.85, 95% CI 1.64-2.09), low educational attainment (aOR 1.76, 95% CI 1.57-1.96), and high sodium intake (U[Na+]/Cr > 16.4 mmol/mmol; aOR 1.29, 95% CI 1.16-1.44). In a subgroup analysis, a robust effect on cataracts across U[Na+]/Cr quartiles was observed in patients ≥ 50 years of age (aOR 1.11, 95% CI 1.04-1.18), though not in younger patients (aOR 1.06, 95% CI 0.96-1.17). CONCLUSIONS: Our results suggest that high sodium intake and low socioeconomic status may affect the development of cataracts, and that a low-salt diet could be helpful for the prevention of cataracts in an older population. Furthermore, efforts to close gaps in health services due to socioeconomic factors may contribute to a reduction in the prevalence of cataracts.

Are increased levels of systemic oxidative stress and inflammation associated with age-related cataract?

Oxidative stress and inflammation may be involved in the etiology of age-related cataract. This study is the first to investigate the association between urinary levels of 8-iso-prostaglandin F2α (PGF2α; as a biomarker for systemic oxidative stress in vivo) and 15-keto-dihydro-PGF2α (as a biomarker for systemic inflammation in vivo) and risk of age-related cataract. We observed in a nested case-control study, including 258 women with incident cataract diagnosis and/or cataract extraction and 258 women without cataract, matched on age and date of urine sample collection that, women with higher levels of urinary 8-iso-PGF2α as compared with lower levels had an increased risk of age-related cataract. There was no difference in 15-keto-dihydro-PGF2α levels between cases and controls. Our observations lead to the hypothesis that higher systemic oxidative stress increases the risk of developing age-related cataract.

Urinary 6-sulphatoxymelatonin levels in patients with senile cataracts.

BACKGROUND: The antioxidant melatonin effectively scavenges highly toxic hydroxyl radicals. Decreases in circulating melatonin levels have been reported in patients with diseases that become more serious with advancing age. The purpose of the present study was to explore the relationship between circulatory melatonin level and the extent of senile cataracts. To this end, we assessed the urinary excretion levels of 6-sulphatoxymelatonin (aMTS6), a major metabolite of melatonin. METHODS: A total of 22 patients (aged 64 ± 7 years; 12 males and 10 females) with senile cataracts and 22 healthy controls (aged 61 ± 8 years, 12 males and 10 females) were studied. aMTS6 urine levels were measured using commercial ELISA kits. Each aMTS6 level was expressed as [aMTS6] (in ng)/[mg] creatinine. As the data were not normally distributed, the Mann-Whitney U-test was employed to assess the statistical validity of the difference observed. RESULTS: The aMT6 level in nocturnal urine was 17.87 ± 14.43 ng aMTS6/mg creatinine (mean ± SD) in senile cataract patients; this was 76% of the level measured in age- and gender-matched controls (23.28 ± 16.27 ng aMTS6/mg creatinine). This difference in nocturnal urine aMTS6 level between senile cataract patients and controls was not statistically significant (p = 0.358). CONCLUSION: The urinary aMTS6 level did not differ between subjects with and without senile cataracts.

Interaction between environmental tobacco smoke and arsenic methylation ability on the risk of bladder cancer.

OBJECTIVE: Arsenic exposure and environmental tobacco smoke (ETS) have been suspected to be associated with bladder cancer risk. We hypothesize that interaction between ETS and the ability to methylate arsenic, a detoxification pathway, modifies the risk of bladder cancer. METHODS: From January 1996 to December 1999, we identified 41 newly diagnosed bladder cancer patients and 202 fracture and cataract patients at the National Cheng-Kung University (NCKU) Medical Center. The levels of urinary arsenic species [As(III), As(V), MMA(V), and DMA(V)] were determined in all subjects. RESULTS: We found significant interaction between ETS and secondary methylation index (SMI) on the risk of bladder cancer (p=0.02). Among non-smokers with a high primary methylation index (PMI), the risk of bladder cancer was lower in subjects exposed to ETS (OR, 0.37; 95% CI, 0.14-0.96) than in subjects without exposure to ETS. Among non-smokers without ETS, the risk of bladder cancer was 4.7 times higher in subjects with a low SMI (95% CI, 1.30-16.81) than in subjects with a high SMI. CONCLUSIONS: Ability to methylate arsenic plays an important role in reducing the risk of bladder cancer attributable to the continuation of arsenic exposure from drinking water and from ETS exposure.

Ocular findings in glutaric aciduria type 1.

PURPOSE: To determine the nature and course of ocular abnormalities in glutaric aciduria (acidemia) type 1 (GA1). METHODS: Fifteen children with GA1 have been studied in the Republic of Ireland. A retrospective review of the records of the 6 children who died during their illness and prospective clinical examination of 9 survivors were performed. RESULTS: Seven of the 15 children had abnormal eye findings. Ocular complications included intraretinal hemorrhages, cataract, gaze palsy, strabismus, ametropia, and pigmentary retinopathy. CONCLUSION: Ocular involvement is common in glutaric aciduria. Complete ophthalmologic evaluation is recommended in all patients suspected to have this rare disease. Intraretinal hemorrhages due to GA1 could be misinterpreted as resulting from child abuse, and it is important to include this disorder with the differential diagnosis of child abuse.

First report of congenital or infantile cataract in deranged proteoglycan metabolism with released xylose.

AIM: To investigate the chemical pathology in the blood and lens, in cases of congenital or infantile cataract in children excreting predominantly non-reducing carbohydrates in urine. METHODS: Urine samples from children with congenital or infantile cataract, and age and sex-matched controls, were analysed for (i) inherited errors of metabolism, (ii) paper chromatography of sugars, (iii) spectrophotometric assay of glycosaminoglycans (GAG), (iv) cetyl trimethyl ammonium bromide test, (v) electrophoresis using Alcian blue, (vi) ion exchange chromatography with IR 120 resin, and (vii) HPLC for xylose. Blood and lens material were also tested for GAG fragments and xylose. beta Glucuronidase was assayed in lymphocytes and urine. RESULTS: Of 220 children of both sexes below 12 years of age, with congenital or infantile cataract treated in Sankara Nethralaya, Madras, India, during a period of 2 years, 145 excreted fragments of GAG (heparan and chondroitin sulphates) in their urine. There was no such excretion among the control group of 50 children. The same was found accumulated in the blood and lenses of affected children. In addition, xylose was present in small amounts in the urine and blood and xylitol was present in the lens. There was a significant elevation in the activity of beta glucuronidase in lymphocytes and urine, when compared with normals. All the above findings suggest deranged proteoglycan metabolism. As the urine contained mostly GAG fragments and very little xylose, Benedict's reagent was not reduced. This ruled out galactosaemia. CONCLUSION: An increase of beta glucuronidase activity might have caused extensive fragmentation of GAG with resultant accumulation in the blood and lens and excretion in urine. Small amounts of xylose may have come from xylose links between GAG and core protein of proteoglycans. Owing to their polyanionic nature, GAG fragments in the lens might abstract sodium, and with it water, thereby increasing the hydration of the lens. Excessive hydration and the osmotic effect of xylitol from xylose might cause cataract. While corneal clouding has been reported in inborn acid mucopolysaccharidosis, congenital or infantile cataract with deranged metabolism of proteoglycans (acid mucopolysaccharide-xylose-protein complex) is reported in children for the first time.

Radio-isotopic determination of hydrogen peroxide in aqueous humor and urine.

The concentrations of hydrogen peroxide in the aqueous humor and urine of several animal species and humans have been determined. The determinations are based on peroxide-dependent decarboxylation of I-[14C]-alpha-ketoglutaric acid and measurement of the resulting 14CO2 by quantitating the radioactive disintegration. The levels of H2O2 in most animals varied between 5.0 and 41 microM for aqueous, and 115 and 187 microM for urine. The levels of peroxide in the urine of steer, cat and baboon were lower and fell out of the above range. In the aqueous of humans with cataracts, the levels ranged from 33 to 324 microM, the overall average being 189 +/- 88 microM. The source of such high levels in the aqueous of cataract patients is currently being studied.

Aminoácidos e cataratas congênitas näo sindrômicas / Aminoacids and non syndromic congenital cataracts

O Autor analisou, através da cromatografia por troca iônica, a urina de pacientes portadores de cataratas congênitas. Através do exame clínico, neurológico e oftalmológico excluí, destas cataratas, fator infeccioso, tóxico ou sindrômico que as pudessem deflagrar. Seus resultados säo discriminados conforme a faixa etária em (dois) grupos: Grupo I - pacientes com mais de dois anos de idade, em 12 foram estudados os Aminoácidos na urina. Grupo II - pacientes com menos de dois anos de idade em que 9 outros pacientes foram estudados. O autor, comparando os resultados, concluiu por uma tendência flagrante de diminuiçäo do teor dos Aminoacidos no grupo estatisticamente mais numeroso (paciente com mais de dois anos de idade), e um aumento deste teor nos pacientes com menos de dois anos de idade