Daniel S. Grossman

Ocular complications after anti-vascular endothelial growth factor therapy in Medicare patients with age-related macular degeneration.

PURPOSE To determine longitudinal rates of ocular complications after anti-vascular endothelial growth factor (VEGF) treatment for neovascular age-related macular degeneration (AMD) in a nationally representative longitudinal sample. DESIGN Retrospective, longitudinal case-control study. METHODS Using the Medicare 5% claims database, diagnoses of neovascular AMD and anti-VEGF injections of ranibizumab, bevacizumab, or pegaptanib were identified from International Classification of Diseases and Current Procedural Terminology procedure codes. Six thousand one hundred fifty-four individuals undergoing anti-VEGF treatment for neovascular AMD (total of 40 903 injections) were compared with 6154 matched controls with neovascular AMD who did not undergo anti-VEGF treatment. Propensity score matching was used to match individuals receiving anti-VEGF injections with controls. Rates of postinjection adverse outcomes (endophthalmitis, rhegmatogenous retinal detachment, retinal tear, uveitis, and vitreous hemorrhage) were analyzed by cumulative incidence and Cox proportional hazards model to control for demographic factors and ocular comorbidities. RESULTS At the 2-year follow-up, the rates of endophthalmitis per injection (0.09%; P<.01), uveitis (0.11%; P<.01), and vitreous hemorrhage per injection (0.23%; P < .01) were significantly higher in the anti-VEGF treatment group. With Cox proportional hazards modeling, the anti-VEGF treatment group had a 102% higher risk of severe ocular complications overall and a 4% increased risk per injection, both of which were statistically significant (P<.01). CONCLUSIONS Rates of endophthalmitis, uveitis, and vitreous hemorrhage were higher in the group treated with anti-VEGF injection than in the control group, although these nevertheless were rare in both groups. The overall risk of severe ocular complications was significantly higher in the anti-VEGF treatment group.

Incidence of Nonarteritic Anterior Ischemic Optic Neuropathy: Increased Risk Among Diabetic Patients

OBJECTIVE Previous studies have identified a higher prevalence of diabetes mellitus (DM) among patient cohorts with nonarteritic anterior ischemic optic neuropathy (NAION). We sought to determine the development of incident NAION among a group of newly diagnosed patients with DM and to estimate the incidence of NAION among the elderly. DESIGN Medicare 5% database study. PARTICIPANTS A total of 25 515 patients with DM and an equal number of age- and gender-matched nondiabetic patients. METHODS Query of Medicare 5% claims files identified patients with a new diagnosis of DM in 1994. A randomly selected control group was created using 1-to-1 propensity score matching. Patients with a diagnosis of giant cell arteritis, preexisting DM, and age 68 years or older or >95 years were excluded. Patients with DM and controls were followed for the development of NAION over the following 4745 days. MAIN OUTCOME MEASURES Incidence of NAION among patients with and without DM. RESULTS In each group, 85% were white, 11% were black, and 4% were other race. Patients were aged 76.4 years, and 40% were male. Mean follow-up was 7.6 years. In the diabetes group, 188 individuals developed NAION (0.7%) compared with 131 individuals (0.5%; P < 0.01) in the control group. In unadjusted Cox regression analysis, having DM was associated with a 43% increased risk (hazard ratio [HR]: 1.431; 95% confidence interval [CI], 1.145-1.789) of developing NAION. After adjusting for other covariates, the risk of developing NAION among individuals with DM was reduced to 40% (HR 1.397; 95% CI, 1.115-1.750). Male gender increased an individuals risk of developing NAION by 32% (HR 1.319; 95% CI, 1.052-1.654). No other covariate was statistically significantly associated with developing NAION. The annual incidence of NAION was 82 per 100 000 persons. CONCLUSIONS Diabetes mellitus significantly increased the risk of the diagnosis NAION. The incidence of NAION among patients aged more than 67 years may be higher than previously reported.

Severe adverse events after cataract surgery among medicare beneficiaries.

PURPOSE To determine rates and risk factors associated with severe postoperative complications after cataract surgery and whether they have been changing over the past decade. DESIGN Retrospective longitudinal cohort study. PARTICIPANTS A total of 221 594 Medicare beneficiaries who underwent cataract surgery during 1994-2006. METHODS Beneficiaries were stratified into 3 cohorts: those who underwent initial cataract surgery during 1994-1995, 1999-2000, or 2005-2006. One-year rates of postoperative severe adverse events (endophthalmitis, suprachoroidal hemorrhage, retinal detachment) were determined for each cohort. Cox regression analyses determined the hazard of developing severe adverse events for each cohort with adjustment for demographic factors, ocular and medical conditions, and surgeon case-mix. MAIN OUTCOME MEASURES Time period rates of development of severe postoperative adverse events. RESULTS Among the 221 594 individuals who underwent cataract surgery, 0.5% (1086) had at least 1 severe postoperative complication. After adjustment for confounders, individuals who underwent cataract surgery during 1994-1995 had a 21% increased hazard of being diagnosed with a severe postoperative complication (hazard ratio [HR] 1.21; 95% confidence interval [CI], 1.05-1.41) relative to individuals who underwent cataract surgery during 2005-2006. Those who underwent cataract surgery during 1999-2000 had a 20% increased hazard of experiencing a severe complication (HR 1.20; 95% CI, 1.04-1.39) relative to the 2005-2006 cohort. Risk factors associated with severe adverse events include a prior diagnosis of proliferative diabetic retinopathy (HR 1.62; 95% CI, 1.07-2.45) and cataract surgery combined with another intraocular surgical procedure on the same day (HR 2.51; 95% CI, 2.07-3.04). Individuals receiving surgery by surgeons with the case-mix least prone to developing a severe adverse event (HR 0.52; 95% CI, 0.44-0.62) had a 48% reduced hazard of a severe adverse event relative to recipients of cataract surgery performed by surgeons with the case-mix most prone to developing such outcomes. CONCLUSIONS Rates of sight-threatening adverse events after cataract surgery declined during 1994-2006. Future efforts should be directed to identifying ways to reduce severe adverse events in high-risk groups.

Adverse Events After Pars Plana Vitrectomy Among Medicare Beneficiaries

OBJECTIVES To assess the complication rates of pars plana vitrectomy (PPV) among older Americans and to determine whether rates of adverse events and additional operations have changed during the past decade. METHODS Claims data were reviewed to identify all adults aged 68 years or older in the 5% Medicare sample who underwent their first PPV during 1994-1995, 1999-2000, and 2004-2005. One-year rates of severe complications (endophthalmitis, suprachoroidal hemorrhage, or retinal detachment), less severe complications, receipt of an additional operation, and blindness were calculated and compared among the 3 groups using Cox regression. Analyses were adjusted for prior adverse events (during the previous 3 years), demographic characteristics, and comorbid conditions. RESULTS The 1994-1995, 1999-2000, and 2004-2005 cohorts had 3263, 5064, and 5263 patients, respectively. The 1-year severe complication rates did not differ among the 3 groups (range, 4.8%-5.5%). The hazard of a less severe complication or an additional operation was higher in the 2004-2005 cohort than in the earlier cohorts (P < .05 for all comparisons). The hazard of endophthalmitis was higher in black individuals (P = .07) and those of other races (P = .02) than in white patients. CONCLUSIONS During the past decade, rates of severe complications after PPV remained stable, but rates of less severe complications and subsequent operations increased. Future studies should explore the potential factors that explain these changes and the alarming elevated incidence of post-PPV endophthalmitis among nonwhite individuals.

One-year outcomes after retinal detachment surgery among medicare beneficiaries.

PURPOSE To determine longitudinal rates of second retinal detachment operation and postoperative adverse outcomes after retinal detachment surgery in a nationally representative sample of older Americans. DESIGN Retrospective, longitudinal cohort analysis. METHODS A total of 9216 Medicare beneficiaries were identified from the Medicare 5% sample who were diagnosed with rhegmatogenous retinal detachment and underwent primary pars plana vitrectomy (PPV), scleral buckle, pneumatic retinopexy, or laser photocoagulation or cryotherapy alone. Rhegmatogenous retinal detachment, PPV, scleral buckle, pneumatic retinopexy, or laser photocoagulation/cryotherapy was ascertained from International Classification of Diseases and Current Procedural Terminology procedure codes. Rates of second retinal detachment operation and postoperative adverse outcomes were analyzed by cumulative incidence and logistic regression to control for prior adverse outcome measures and demographic factors. RESULTS At 1-year follow-up, the rate of receipt of a second retinal detachment operation for beneficiaries who had undergone primary pneumatic retinopexy was much higher (40.6%, P < .0001) relative to the scleral buckle (19.2%) group. After controlling for demographic variables and ocular comorbidities, pneumatic retinopexy individuals were nearly 3 times more likely to receive a second retinal detachment surgery than scleral buckle individuals. No significant differences exist in risk of second retinal detachment surgery for the PPV compared to the scleral buckle group. Individuals receiving PPV were 2 times more likely to suffer adverse outcomes than were those undergoing scleral buckle. Results were robust in sensitivity analysis. CONCLUSIONS Rates of second operation were much higher after pneumatic retinopexy than PPV or scleral buckle, and rates of adverse outcomes were higher in PPV, even after controlling for risk factors and demographic variables.

Glaucoma, Alzheimer disease and other dementia: A longitudinal analysis

Purpose: To evaluate the risk of developing Alzheimer disease (AD) or other dementia in patients diagnosed with open-angle glaucoma (OAG) in a nationally representative longitudinal sample of elderly persons. Methods: This retrospective cohort study (January 1, 1994–December 31, 2007) used Medicare 5% claims data. We identified beneficiaries aged 68+ years who had at least two claims with diagnoses of OAG and no Alzheimer or other dementia in 1994, using a 3-year look-back period between 1991 and 1993 (n = 63,235) and beneficiaries matched on age, sex, race, and Charlson index without a diagnosis of OAG throughout the observational period (n = 63,235), using propensity score matching. Using a Cox Proportional Hazards model, we analyzed time to AD diagnosis and time to AD or other dementia diagnosis. Results: Elderly individuals diagnosed with OAG did not have an increased rate of AD and other dementia diagnosis compared to those without OAG during a 14-year follow-up period, even after controlling for relevant covariates present at baseline. Conclusions: Individuals aged 68+ years diagnosed with OAG have a decreased rate of AD or other dementia diagnosis compared to control patients without an OAG diagnosis. Although OAG and AD are both age-related neurodegenerative diseases, our findings do not support a positive association.

Effects of Receipt of Guideline- Recommended Care on Onset of Diabetic Retinopathy and Its Progression

OBJECTIVE To determine whether persons in a community setting diagnosed with diabetes who received recommended patterns of care experience improved vision outcomes over a 3-year time period. DESIGN Retrospective, longitudinal, cohort analysis. PARTICIPANTS Persons diagnosed with diabetes mellitus (DM), with no prior diagnosis of diabetic retinopathy (DR; n = 5989) from the Medicare Current Beneficiary Survey (1992-2004). Persons diagnosed with DM were followed up to 3 years. INTERVENTION Propensity score matching was used to compare vision outcomes between persons who received guideline-recommended care and those who did not. Receipt of recommended levels of care was defined as receiving each of the following services 0.75 times annually on average: physician examination, ophthalmologist or optometrist examination, hemoglobin A1c level, lipid levels, and urinalysis. MAIN OUTCOME MEASURES Outcome measures were indicators of DR disease progression: no diagnosed DR to diagnosed background DR, proliferative DR, macular edema, proliferative DR complications, and use of a low-vision aid or blindness. RESULTS Persons with diagnosed diabetes receiving guideline-recommended care experienced earlier onset of background DR (average treatment effects on the treated [ATT] at 3 years, 0.118; 95% confidence interval [CI], -0.005 to 0.240). There were no differences between those receiving recommended care and others in time to onset of proliferative DR, macular edema, or proliferative DR complications. However, persons who received care consistent with recommendations experienced much lower rates of onset of low vision/blindness than did others (ATT at 3 years, -0.109; 95% CI, -0.189 to -0.030). CONCLUSIONS Low vision/blindness was substantially reduced over a 3-year period among persons diagnosed with DM who received recommended levels of care.

Receipt of Care and Reduction of Lower Extremity Amputations in a Nationally Representative Sample of U.S. Elderly

OBJECTIVE To determine effectiveness of receipt of care from podiatrist and lower extremity clinician specialists (LEC specialists) on diabetes mellitus (DM)-related lower extremity amputation. DATA SOURCES Medicare 5 percent sample claims, 1991-2007. STUDY DESIGN Individuals with DM-related lower extremity complications (LECs) were followed 6 years. Visits with podiatrists, LEC specialists, and other health professionals were tracked to ascertain whether receipt of such care reduced the hazards of an LEC amputation. DATA COLLECTION Individuals were stratified based on disease severity, Stage 1--neuropathy, paresthesia, pain in feet, diabetic amyotrophy; Stage 2--cellulitis, charcot foot; Stage 3--ulcer; Stage 4--osteomyelitis, gangrene. PRINCIPAL FINDINGS Half the LEC sample died within 6 years. More severe lower extremity disease increased risk of death and amputation. Persons visiting a podiatrist and an LEC specialist within a year before developing all stage complications were between 31 percent (ulceration) and 77 percent (cellulitis and charcot foot) as likely to undergo amputation compared with individuals visiting other health professionals. CONCLUSIONS Individuals with an LEC had high mortality. Visiting both a podiatrist and an LEC specialist in the year before LEC diagnosis was protective of undergoing lower extremity amputation, suggesting a benefit from multidisciplinary care.

Education and health: evidence on adults with diabetes

Although the education-health relationship is well documented, pathways through which education influences health are not well understood. This study uses data from a 2003–2004 cross sectional supplemental survey of respondents to the longitudinal Health and Retirement Study (HRS) who had been diagnosed with diabetes mellitus to assess effects of education on health and mechanisms underlying the relationship. The supplemental survey provides rich detail on use of personal health care services (e.g., adherence to guidelines for diabetes care) and personal attributes which are plausibly largely time invariant and systematically related to years of schooling completed, including time preference, self-control, and self-confidence. Educational attainment, as measured by years of schooling completed, is systematically and positively related to time to onset of diabetes, and conditional on having been diagnosed with this disease on health outcomes, variables related to efficiency in health production, as well as use of diabetes specialists. However, the marginal effects of increasing educational attainment by a year are uniformly small. Accounting for other factors, including child health and child socioeconomic status which could affect years of schooling completed and adult health, adult cognition, income, and health insurance, and personal attributes from the supplemental survey, marginal effects of educational attainment tend to be lower than when these other factors are not included in the analysis, but they tend to remain statistically significant at conventional levels.

Risk of glaucoma among patients with benign essential blepharospasm.

Purpose: Debate exists whether intraocular pressure fluctuation is a risk factor for glaucoma. Patients with benign essential blepharospasm (BEB) experience intermittent, ultra-short-term intraocular pressure elevations from frequent blinking and spastic eyelid closure. This article explores the development of incident glaucoma after BEB diagnosis. Methods: Medicare claims files were used to identify patients with a diagnosis of BEB from 1994 to 2000. An equal-sized control group consisting of patients without BEB was created using one-to-one propensity score matching. The patients with BEB and those in the control group were followed for the development of one of the following main outcome measures: primary open angle glaucoma (POAG), closed angle glaucoma (CAG), or other glaucoma (besides POAG and CAG) over the following 2,190 days. Results: There were 1,350 persons in each group, consisting of 29% men, 94% of whom were white, with a mean age of 76 years. In the unadjusted model, BEB patients did not develop POAG (hazard ratio [HR], 1.159; 95% confidence interval [CI], 0.876-1.534), CAG (HR, 1.477; 95% CI, 0.711-3.066), or other glaucoma (HR, 1.306; 95% CI, 0.904-1.886) more often than controls. Adjusting for age, gender, race, number of visits to the ophthalmologist, and other eye disease, a diagnosis of BEB did not affect the risk of POAG (HR, 1.152; 95% CI, 0.870-1.525), CAG (HR, 1.448; 95% CI, 0.696-3.015), or other glaucoma (HR, 1.296; 95% CI, 0.896-1.873). Conclusions: BEB is not a risk indicator for POAG, CAG, or other forms of glaucoma.