Cataract surgery and subtype in a defined, older population: the SEECAT Project

Cost-Effectiveness of Preoperative Topical Antibiotic Prophylaxis for Endophthalmitis Following Cataract Surgery

PURPOSE

To determine the cost-effectiveness of preoperative topical antibiotic prophylaxis for the prevention of endophthalmitis following cataract surgery.

DESIGN

Cost-effectiveness analysis using a decision-analytic microsimulation model.

METHODS

Preoperative topical antibiotic prophylaxis vs no-prophylaxis costs and effects were projected over a life-time horizon for a simulated cohort of 500 000 adult patients (≥18 years old) requiring cataract surgery in theoretical surgical centers in the United States. Efficacy and cost (2021 US dollars) values were obtained from the literature and discounted at 3% per year.

RESULTS

Based on inputted parameters, the mean incidence of endophthalmitis following cataract surgery for preoperative topical antibiotic prophylaxis vs no-prophylaxis was 0.034% (95% CI 0%-0.2%) and 0.042% (95% CI 0%-0.3%), respectively-an absolute risk reduction of 0.008%. The mean life-time costs for cataract surgery with prophylaxis and no-prophylaxis were $2486.67 (95% CI $2193.61-$2802.44) and $2409.03 (95% CI $2129.94-$2706.69), respectively. The quality-adjusted life-years (QALYs) associated with prophylaxis and no-prophylaxis were 10.33495 (95% CI 7.81629-12.38158) and 10.33498 (95% CI 7.81284-12.38316), respectively. Assuming a cost-effectiveness criterion of ≤$50 000 per QALY gained, the threshold analyses indicated that prophylaxis would be cost-effective if the incidence of endophthalmitis after cataract surgery was greater than 5.5% or if the price of the preoperative topical antibiotic prophylaxis was less than $0.75.

CONCLUSIONS

General use of preoperative topical antibiotic prophylaxis is not cost-effective compared with no-prophylaxis for the prevention of endophthalmitis following cataract surgery. Preoperative topical antibiotic prophylaxis, however, would be cost-effective at a higher incidence of endophthalmitis and/or a substantially lower price for prophylaxis.

Association between age-related cataract and blepharoptosis in Korean adults: a population-based study

Cataract and blepharoptosis are both commonly encountered ophthalmic problems in older adults. Since they share similar risk factors, it is plausible that there may be an association between the two conditions. We examined data from the Korean National Health and Nutrition Examination Survey (KNHANES) 2010–2012 to determine if there is an association between age-related cataract and blepharoptosis. Multivariable adjusted logistic regression analysis was conducted to examine the odds ratio (OR) and 95% confidence interval (CI) for association of each specific type of cataract with presence of blepharoptosis. Of the 10,387 eligible participants, 4782 (46.0%) had cataract and 1419 (15.8%) had blepharoptosis. There were more participants with blepharoptosis in the cataract group, compared with those in the no cataract group. After adjusting for potential confounders, participants with blepharoptosis had a higher risk of total cataract (OR: 1.557, 95% CI 1.201–2.019) and nuclear subtype cataract (OR: 1.305, 95% CI 1.050–1.620). Blepharoptosis was associated with significantly higher odds of cataract in obese participants when compared with non-obese participants (p for interaction = 0.0236). Our study revealed a positive association between age-related cataract and blepharoptosis; it suggests that thorough ophthalmic assessment is needed when assessing patients who are planning cataract or blepharoptosis surgery.

Cataract risk in US radiologic technologists assisting with fluoroscopically guided interventional procedures: a retrospective cohort study

OBJECTIVES

To assess radiation exposure-related work history and risk of cataract and cataract surgery among radiologic technologists assisting with fluoroscopically guided interventional procedures (FGIP).

METHODS

This retrospective study included 35 751 radiologic technologists who reported being cataract-free at baseline (1994-1998) and completed a follow-up questionnaire (2013-2014). Frequencies of assisting with 21 types of FGIP and use of radiation protection equipment during five time periods (before 1970, 1970-1979, 1980-1989, 1990-1999, 2000-2009) were derived from an additional self-administered questionnaire in 2013-2014. Multivariable-adjusted relative risks (RRs) for self-reported cataract diagnosis and cataract surgery were estimated according to FGIP work history.

RESULTS

During follow-up, 9372 technologists reported incident physician-diagnosed cataract; 4278 of incident cases reported undergoing cataract surgery. Technologists who ever assisted with FGIP had increased risk for cataract compared with those who never assisted with FGIP (RR: 1.18, 95% CI 1.11 to 1.25). Risk increased with increasing cumulative number of FGIP; the RR for technologists who assisted with >5000 FGIP compared with those who never assisted was 1.38 (95% CI 1.24 to 1.53; p trend <0.001). These associations were more pronounced for FGIP when technologists were located ≤3 feet (≤0.9 m) from the patient compared with >3 feet (>0.9 m) (RRs for >5000 at ≤3 feet vs never FGIP were 1.48, 95% CI 1.27 to 1.74 and 1.15, 95% CI 0.98 to 1.35, respectively; pdifference=0.04). Similar risks, although not statistically significant, were observed for cataract surgery.

CONCLUSION

Technologists who reported assisting with FGIP, particularly high-volume FGIP within 3 feet of the patient, had increased risk of incident cataract. Additional investigation should evaluate estimated dose response and medically validated cataract type.

Associations of PARP-1 variant rs1136410 with PARP activities, oxidative DNA damage, and the risk of age-related cataract in a Chinese Han population: A two-stage case-control analysis

OBJECTIVE

To investigate whether a single nucleotide polymorphism (SNP) rs1136410 in the poly (ADP-ribose) polymerase-1 (PARP-1) gene was associated with PARP activities, 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels, and the risk of age-related cataract (ARC) in a Chinese Han population.

METHODS

In this two-stage case-control study with a total of 1010 ARC patients and 1045 controls, SNP rs1136410 was genotyped by high-resolution melting analyses (HRM). PARP activities and 8-OHdG levels in peripheral blood mononuclear cells (PBMCs) were determined by ELISA kits.

RESULTS

In discovery, replication, and their merged sets, the variant genotypes (AG+GG) of SNP rs1136410 were significantly associated with an increased risk of ARC under a dominant model (Adjusted odds ratio (OR)=1.42, P_adj=0.001 for the merged set). This association was further identified in subtype analyses for cortical ARC (Adjusted OR=1.69, P_adj<0.001). In subgroup analyses, we identified a significant interaction between SNP rs1136410 and smoking habit in increasing ARC risk (P_inter=0.019). Moreover, ARC patients had lower activities of PARP and higher levels of 8-OHdG than controls. There were significant correlations of SNP rs1136410 with decreased PARP activities and increased 8-OHdG levels in controls and patients with cortical ARC.

CONCLUSIONS

This study suggests that SNP rs1136410 may confer susceptibility to ARC by affecting PARP activities and oxidative DNA damage.

Geographic Variation in the Rate and Timing of Cataract Surgery Among US Communities

IMPORTANCE

Previous studies using data from the 1980s found relatively little geographic variation in cataract surgery rates across the United States. We do not know whether similar patterns hold true today, nor do we know the patient- and community-level factors that might explain any recent geographic variations in the rate and timing of cataract surgery.

OBJECTIVE

To assess the extent of geographic variation in patient age at initial cataract surgery and the age-standardized cataract surgery rate in a large group of insured US patients with cataracts.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cross-sectional study of 1 050 815 beneficiaries older than 40 years of age with cataracts who were enrolled in a nationwide managed-care network during the period from 2001 to 2011. The data analysis was started in 2014 and refined in 2015.

MAIN OUTCOMES AND MEASURES

Median age at initial cataract extraction, age-standardized cataract surgery rate, and time from initial diagnosis to first surgery for patients with cataracts were compared among 306 US communities. Multivariable regression modeling generated hazard ratios (HRs) with 95% CIs identifying factors associated with patients' likelihood of undergoing cataract surgery.

RESULTS

A total of 243 104 patients with cataracts (23.1%) underwent 1 or more surgical procedures (55.1% were female patients). Communities with the youngest and oldest patients at initial surgery differed in age by nearly 20 years (59.9-60.1 years in Lansing, Michigan, and Aurora, Illinois, vs 77.0-79.6 years in Marquette, Michigan; Rochester, New York; and Binghamton, New York). The highest age-standardized cataract surgery rate (37.3% in Lake Charles, Louisiana) was 5-fold higher than the lowest (7.5% in Honolulu, Hawaii). The median time from initial cataract diagnosis to date of first surgery ranged from 17 days (Victoria, Texas) to 367 days (Yakima, Washington). Compared with white patients, black patients had a 15% decreased hazard of surgery (HR, 0.85 [95% CI, 0.83-0.87]), while Latino patients (HR, 1.08 [95% CI, 1.05-1.10]) and Asian patients (HR, 1.09 [95% CI, 1.05-1.12]) had an increased hazard. For every 1° higher latitude, the hazard of surgery decreased by 1% (HR, 0.99 [95% CI, 0.98-0.99]). For every additional optometrist per 100 000 enrollees in a community, the hazard of surgery increased 0.1% (HR, 1.001 [95% CI, 1.001-1.001]).

CONCLUSIONS AND RELEVANCE

In recent years, patient age at first cataract surgery and the age-standardized surgery rate have varied considerably among some US communities. Future research should explore the extent to which such variations may affect patient outcomes.

Polymorphisms of the WRN gene and DNA damage of peripheral lymphocytes in age-related cataract in a Han Chinese population

Werner syndrome is caused by mutations in the DNA repair Werner helicase (WRN) gene and characterized by accelerated aging including cataracts. Age-related cataract (ARC) cases (N = 504) and controls (N = 244) were recruited from a population-based study to evaluate the association of single-nucleotide polymorphisms (SNPs) of WRN and another DNA repair gene (human 8-oxoguanine DNA N-glycosylase 1) with ARC. Among the five SNPs tested, only WRN rs1346044 was found to be significantly associated between cases and controls before multiple-testing adjustment. The minor C allele of rs1346044 was associated with ARC with an odds ratio (OR) of 0.66, suggesting a protective role of the C allele for developing ARC. The stratification analysis on the subtypes of ARC showed that rs1346044 was significantly associated with cortical cataract, but not with nuclear, posterior subcapsular, and mixed types after multiple-testing adjustment (OR = 0.51, p< 0.01). The genetic model analysis showed that the results fit the dominant model (OR = 0.44, p < 0.001). The comet assay used to assess the extent of DNA damage in peripheral lymphocytes of ARC cases found that the DNA damage in lymphocytes from patients with CC genotype was significantly less than that in patients with TT genotype. We concluded that the C allele of rs1346044, a non-synonymous SNP resulting in the conversion of Cys to Arg at amino acid position 1367 of WRN, alters susceptibility to ARC, especially the cortical type of the disease, in the Han Chinese. The underlying mechanism of its protective role might be related to the improved DNA repair function.

Lutein/zeaxanthin for the treatment of age-related cataract: AREDS2 randomized trial report no. 4

IMPORTANCE

Age-related cataract is a leading cause of visual impairment in the United States. The prevalence of age-related cataract is increasing, with an estimated 30.1 million Americans likely to be affected by 2020.

OBJECTIVE

To determine whether daily oral supplementation with lutein/zeaxanthin affects the risk for cataract surgery.

DESIGN, SETTING, AND PATIENTS

The Age-Related Eye Disease Study 2 (AREDS2), a multicenter, double-masked clinical trial, enrolled 4203 participants, aged 50 to 85 years, at risk for progression to advanced age-related macular degeneration.

INTERVENTIONS

Participants were randomly assigned to daily placebo; lutein/zeaxanthin, 10mg/2mg; omega-3 long-chain polyunsaturated fatty acids, 1 g; or a combination to evaluate the effects on the primary outcome of progression to advanced age-related macular degeneration.

MAIN OUTCOMES AND MEASURES

Cataract surgery was documented at annual study examination with the presence of pseudophakia or aphakia, or reported during telephone calls at 6-month intervals between study visits. Annual best-corrected visual acuity testing was performed. A secondary outcome of AREDS2 was to evaluate the effects of lutein/zeaxanthin on the subsequent need for cataract surgery.

RESULTS

A total of 3159 AREDS2 participants were phakic in at least 1 eye and 1389 of 6027 study eyes underwent cataract surgery during the study, with median follow-up of 4.7 years. The 5-year probability of progression to cataract surgery in the no lutein/zeaxanthin group was 24%. For lutein/zeaxanthin vs no lutein/zeaxanthin, the hazard ratios for progression to cataract surgery was 0.96 (95% CI, 0.84-1.10; P = .54). For participants in the lowest quintile of dietary intake of lutein/zeaxanthin, the hazard ratio comparing lutein/zeaxanthin vs no lutein/zeaxanthin for progression to cataract surgery was 0.68 (95% CI, 0.48-0.96; P = .03). The hazard ratio for 3 or more lines of vision loss was 1.03 (95% CI, 0.93-1.13; P = .61 for lutein/zeaxanthin vs no lutein/zeaxanthin).

CONCLUSIONS AND RELEVANCE

Daily supplementation with lutein/zeaxanthin had no statistically significant overall effect on rates of cataract surgery or vision loss.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00345176.

Shotgun proteomic analysis of S-thiolation sites of guinea pig lens nuclear crystallins following oxidative stress in vivo

PURPOSE

To compare levels of S-glutathiolation and S-cysteinylation occurring at more than 60 cysteine residues of 12 different guinea pig lens water-soluble nuclear crystallins following treatment of the animals with hyperbaric oxygen (HBO).

METHODS

Guinea pigs (initially 18 months old) were treated 30X (3X per week for 10 weeks) with HBO (2.5 atm 100% O(2) for 2.5 h) as a model to study the formation of nuclear cataract. This treatment produces a moderate increase in lens nuclear light scatter (compared to denser scatter occurring after 80 HBO treatments), with five- to sixfold increases in levels of protein-bound glutathione (PSSG) and protein-bound cysteine (PSSC). Trypsin digests of lens nuclear water-soluble proteins were analyzed with two-dimensional liquid chromatography and mass spectrometry to identify specific cysteine residues binding either glutathione or cysteine. Lens nuclei of age-matched untreated animals were used as controls.

RESULTS

All major crystallins, except αB, were modified to some extent by either S-glutathiolation or S-cysteinylation. Overall, 72% of the cysteine residues of guinea pig lens nuclear crystallins were shown to be capable of binding glutathione, cysteine, or both molecules. The crystallin with the highest level of modification was βA1/A3 (six of eight -SH groups), and that with the lowest (two of five -SH groups) was βA2. O(2)-induced increases in PSSG levels were 2.8, 2.4, and 4.1 times control for γA-, γB-, and γC-crystallins, respectively. Comparable increases in PSSC levels for the three γ-crystallins were 2.3, 2.7, and 2.4 times control, respectively. βB2-crystallin showed the highest amount of O(2)-induced PSSG formation of any of the crystallins, as well as a substantial level of control PSSG, and nearly all of this was due to a single residue, C67, a site also present in human βB2-crystallin. Overall, 32 of the 44 modified cysteine residues were homologous with the human.

CONCLUSIONS

This large-scale study successfully identified lens crystallin cysteine residues that bound glutathione and/or cysteine under normal or oxidative stress conditions. The high percentage of protein -SH groups that are modified by S-thiolation in the guinea pig lens nucleus demonstrates the substantial protein sulfhydryl redox buffer capability present in the center of the lens. The results suggest that PSSG and PSSC formation may act to delay O(2)-induced insolubilization of γA-, γB-, and γC-crystallins, and β-crystallins, but with a greater effect on the γ-crystallins at an early stage of oxidative stress. The study has shown that technological approaches are now available to investigate in considerable detail the role of specific lens -SH groups in nuclear cataractogenesis.

Glutathione and catalase suppress TGFbeta-induced cataract-related changes in cultured rat lenses and lens epithelial explants

PURPOSE

The damaging effects of oxidative stress and transforming growth factor-beta (TGFbeta)-induced transdifferentiation of lens epithelial cells have both been implicated independently in the etiology of cataract. The aim of this study was to investigate whether the presence of antioxidant systems in the lens influences the ability of lens epithelial cells to respond to TGFbeta.

METHODS

Whole lenses from young rats were cultured with or without TGFbeta in the presence or absence of reduced glutathione (GSH). Lens epithelial explants from weanling rats were used to investigate the effects of GSH and catalase on TGFbeta-induced cataract-related changes. Lenses were monitored for opacification for three to four days, photographed, and then processed for routine histology. Explants were assessed by phase contrast microscopy, enzyme-linked immunosorbent assay (ELISA) of alpha-smooth muscle actin (alphaSMA), and/or immunolocalization of alphaSMA and Pax6, markers for transdifferentiation and normal lens epithelial phenotype, respectively.

RESULTS

In cultured lenses, GSH strongly suppressed TGFbeta-induced opacification and subcapsular plaque formation. In explants, both GSH and catalase suppressed changes typically associated with TGFbeta-induced transdifferentiation including wrinkling of the lens capsule, cell-surface blebbing, apoptotic cell loss, induction of alphaSMA, and loss of Pax6 expression.

CONCLUSIONS

This study suggests that antioxidant systems present in the normal lens, which protect the epithelium against the damaging effects of reactive oxygen species, may also serve to protect it against the potentially cataractogenic effects of TGFbeta. Taken together with other recent studies, it also raises the possibility that TGFbeta may induce cataract-related changes in lens epithelial cells via release of hydrogen peroxide.

A randomized, double-masked, placebo-controlled clinical trial of multivitamin supplementation for age-related lens opacities. Clinical trial of nutritional supplements and age-related cataract report no. 3

OBJECTIVE

To evaluate the effect of a multivitamin/mineral supplement on development or progression of age-related lens opacities.

DESIGN

Randomized, double-masked, single center, placebo-controlled clinical trial.

PARTICIPANTS

One thousand twenty participants, 55 to 75 years old and with early or no cataract, were randomly assigned to a daily tablet of a multivitamin/mineral formulation or a placebo.

METHODS

Baseline and annual lens photographs were graded for severity of lens opacities according to a modification of the Age-Related Eye Disease Study system for classifying cataracts.

MAIN OUTCOME MEASURES

The primary outcome was a prespecified increase from baseline in nuclear, cortical, or posterior subcapsular cataract (PSC) opacity grades or cataract surgery. Secondary outcomes included an increase in type-specific opacity grades, cataract surgery, and visual acuity (VA) loss from baseline > or =15 letters.

RESULTS

Participants were observed for an average of 9.0+/-2.4 years. There was a decrease in total lens events in participants assigned to the multivitamin/mineral formulation compared with those assigned to the placebo (hazard ratio [HR], 0.82; 95% confidence interval [CI], 0.68-0.98; P = 0.03). Nuclear events were significantly less common (HR, 0.66; 95% CI, 0.50-0.88; P = 0.004) and PSC events significantly more common (HR, 2.00; 95% CI, 1.35-2.98; P<0.001) in participants taking the multivitamin/mineral formulation than in those assigned to the placebo. No statistically significant treatment effects were seen for cortical opacities, moderate VA loss, or cataract surgery.

CONCLUSIONS

Lens events were less common in participants who took the multivitamin/mineral formulation, but treatment had opposite effects on the development or progression of nuclear and PSC opacities, the 2 most visually important opacity subtypes.

Incidence of cataract surgery from 1980 through 2004: 25-year population-based study

PURPOSE

To estimate sex- and age-specific incidence rates of cataract surgery in a defined United States population and evaluate the change in incidence over time.

SETTING

Department of Ophthalmology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.

METHODS

Rochester Epidemiology Project databases were used to identify all incident cataract surgeries in Olmsted County, Minnesota, residents during the 25-year period from January 1, 1980, through December 31, 2004. Annual incidence rates for each sex and 10-year age group were calculated and adjusted to the 2000 U.S. white population. Change in incidence over time was assessed by fitting generalized linear models assuming a Poisson error structure.

RESULTS

During the study period, 10 245 cataract extractions were performed in 7141 residents of all ages. Overall, the age-adjusted cataract surgery incident rate per 100000 residents was 548 (95% confidence interval [CI], 534-561) for women, 462 (95% CI, 447-478) for men, and 511 (95% CI, 501-521) for all residents. The incidence of cataract surgery increased 500% among women and 467% among men during the study period (P<.001). Overall, the incidence of cataract surgery was highest in residents 70 years and older (3538 surgeries [95% CI, 3322-3764] per 100,000 residents).

CONCLUSIONS

This population-based study found a substantial increase in incident cataract surgery among Olmsted County residents during the 25-year study period. The rate of cataract surgery increased in a nearly linear fashion during a period when phacoemulsification replaced extracapsular cataract extraction in the community.

Aggregation of lens crystallins in an in vivo hyperbaric oxygen guinea pig model of nuclear cataract: dynamic light-scattering and HPLC analysis

PURPOSE

The role of oxygen in the formation of lens high-molecular-weight (HMW) protein aggregates during the development of human nuclear cataract is not well understood. The purpose of this study was to investigate lens crystallin aggregate formation in hyperbaric oxygen (HBO)-treated guinea pigs by using in vivo and in vitro

METHODS

methods. Guinea pigs were treated three times weekly for 7 months with HBO, and lens crystallin aggregation was investigated in vivo with the use of dynamic light-scattering (DLS) and in vitro by HPLC analysis of water-insoluble (WI) proteins. DLS measurements were made every 0.1 mm across the 4.5- to 5.0-mm optical axis of the guinea pig lens.

RESULTS

The average apparent diameter of proteins in the nucleus (the central region) of lenses of HBO-treated animals was nearly twice that of the control animals (P < 0.001). Size distribution analysis conducted at one selected point in the nucleus and cortex (the outer periphery of the lens) after dividing the proteins into small-diameter and large-diameter groups, showed in the O2-treated nucleus a threefold increase in intensity (P < 0.001) and a doubling in apparent size (P = 0.03) of large-diameter aggregate proteins, compared with the same control group. No significant changes in apparent protein diameter were detected in the O2-treated cortex, compared with the control. The average diameter of protein aggregates at the single selected location in the O2-treated nucleus was estimated to be 150 nm, a size capable of scattering light and similar to the size of aggregates found in human nuclear cataracts. HPLC analysis indicated that one half of the experimental nuclear WI protein fraction (that had been dissolved in guanidine) consisted of disulfide cross-linked 150- to 1000-kDa aggregates, not present in the control. HPLC-isolated aggregates contained alphaA-, beta-, gamma-, and zeta-crystallins, but not alphaB-crystallin, which is devoid of -SH groups and thus does not participate in disulfide cross-linking. All zeta-crystallin present in the nuclear WI fraction appeared to be there as a result of disulfide cross-linking.

CONCLUSIONS

The results indicate that molecular oxygen in vivo can induce the cross-linking of guinea pig lens nuclear crystallins into large disulfide-bonded aggregates capable of scattering light. A similar process may be involved in the formation of human nuclear cataract.

Nuclear cataract shows significant familial aggregation in an older population after adjustment for possible shared environmental factors

PURPOSE

To quantify the association between siblings in age-related nuclear cataract, after adjusting for known environmental and personal risk factors.

METHODS

All participants (probands) in the Salisbury Eye Evaluation (SEE) project and their locally resident siblings underwent digital slit lamp photography and were administered a questionnaire to assess risk factors for cataract including: age, gender, lifetime sun exposure, smoking and diabetes history, and use of alcohol and medications such as estrogens and steroids. In addition, blood pressure, body mass index, and serum antioxidants were measured in all participants. Lens photographs were graded by trained observers masked to the subjects' identity, using the Wilmer Cataract Grading System. The odds ratio for siblings for affectedness with nuclear cataract and the sibling correlation of nuclear cataract grade, after adjusting for covariates, were estimated with generalized estimating equations.

RESULTS

Among 307 probands (mean age, 77.6 +/- 4.5 years) and 434 full siblings (mean age, 72.4 +/- 7.4 years), the average sibship size was 2.7 per family. After adjustment for covariates, the probability of development of nuclear cataract was significantly increased (odds ratio [OR] = 2.07, 95% confidence interval [CI], 1.30-3.30) among individuals with a sibling with nuclear cataract (nuclear grade > or = 3.0). The final fitted model indicated a magnitude of heritability for nuclear cataract of 35.6% (95% CI: 21.0%-50.3%) after adjustment for the covariates.

CONCLUSIONS

Findings in this study are consistent with a genetic effect for age-related nuclear cataract, a common and clinically significant form of lens opacity.