Metformin Use and Age-Related Macular Degeneration in Patients Without Diabetes.

Importance: Metformin use may protect against the development of age-related macular degeneration (AMD) based on results from observational studies. However, its potential effectiveness among patients without diabetes remains unclear. Objective: To assess the association between metformin use and the development of AMD in patients without diabetes. Design, Setting, and Participants: This case-control study used data from 2006 to 2017 in the Merative MarketScan Research Database, a nationwide insurance claims database that includes between 27 and 57 million patients in the US with primary or Medicare supplemental health insurance. Cases with AMD and controls without AMD aged 55 years or older were matched 1:1 by year, age, anemia, hypertension, region, and Charlson Comorbidity Index score. Then, cases and matched controls without a diagnosis of diabetes were selected. In subgroup analyses, cases with dry AMD and their matched controls were identified to explore the association between metformin use and AMD staging in patients without diabetes. Data were analyzed between March and September 2023. Exposures: Exposure to metformin in the 2 years prior to the index date (ie, date of AMD diagnosis in cases and date of a randomly selected eye examination for controls) was assessed from the claims database and categorized into quartiles based on cumulative dose (1-270, 271-600, 601-1080, and >1080 g/2 y). Exposure to other antidiabetic medications was also noted. Main Outcomes and Measures: Odds of new-onset AMD development as assessed by multivariable conditional logistic regression after adjusting for known risk factors for AMD, including female sex, hyperlipidemia, smoking, and exposures to other antidiabetic medications. Asymptotic Cochran-Armitage tests for trend were also performed. Results: We identified 231 142 patients with any AMD (mean [SD] age, 75.1 [10.4] years; 140 172 females [60.6%]) and 232 879 matched controls without AMD (mean [SD] age, 74.9 [10.5] years; 133 670 females [57.4%]), none of whom had a diagnosis of diabetes. The sample included 144 147 cases with dry AMD that were matched to 144 530 controls. In all, 2268 (1.0%) cases and 3087 controls (1.3%) were exposed to metformin in the 2 years before their index visit. After data adjustment, exposure to any metformin was associated with reduced odds of any AMD development (adjusted odds ratio [AOR], 0.83; 95% CI, 0.74-0.87), specifically in the dosing quartiles of 1 to 270, 271 to 600, and 601 to 1080 g/2 y. Any metformin use was also associated with a reduced odds of developing dry AMD (AOR, 0.85; 95% CI, 0.79-0.92), specifically in the dosing quartiles of 1 to 270 and 271 to 600 g/2 y. Adjusted odds ratios for any AMD and dry AMD development did not differ across the dosing quartiles. Asymptotic Cochran-Armitage tests for trend revealed 2-sided P = .51 and P = .66 for the any and dry AMD samples, respectively. Conclusions and Relevance: In this case-control study of a population without a diagnosis of diabetes, metformin use was associated with reduced odds of developing AMD. This association does not appear to be dose dependent. These findings provide further impetus to study metformin's usefulness in protecting against AMD in prospective clinical trials.

Glyburide confers neuroprotection against age-related macular degeneration (AMD).

Glyburide, a sulfonylurea drug used to treat type 2 diabetes, boasts neuroprotective effects by targeting the sulfonylurea receptor 1 (SUR1) and associated ion channels in various cell types, including those in the central nervous system and the retina. Previously, we demonstrated that glyburide therapy improved retinal function and structure in a rat model of diabetic retinopathy. In the present study, we explore the application of glyburide in non-neovascular ("dry") age-related macular degeneration (AMD), another progressive disease characterized by oxidative stress-induced damage and neuroinflammation that trigger cell death in the retina. We show that glyburide administration to a human cone cell line confers protection against oxidative stress, inflammasome activation, and apoptosis. To corroborate our in vitro results, we also conducted a case-control study, controlling for AMD risk factors and other diabetes medications. It showed that glyburide use in patients reduces the odds of new-onset dry AMD. A positive dose-response relationship is observed from this analysis, in which higher cumulative doses of glyburide further reduce the odds of new-onset dry AMD. In the quest for novel therapies for AMD, glyburide emerges as a promising repurposable drug given its known safety profile. The results from this study provide insights into the multifaceted actions of glyburide and its potential as a neuroprotective agent for retinal diseases; however, further preclinical and clinical studies are needed to validate its therapeutic potential in the context of degenerative retinal disorders such as AMD.

Trends in Secondary Intraocular Lens Surgery among Vitreoretinal Surgeons.

OBJECTIVE: To identify changes in secondary lens techniques over time and to determine common complications of each technique. DESIGN: Retrospective cohort study. PARTICIPANTS: All patients in the database from January 2015 to December 2021 who underwent secondary lens placement (anterior chamber intraocular lens [IOL, ACIOL], scleral-fixated IOL [SFIOL], or scleral-sutured IOL [SSIOL]). METHODS: Rates of secondary IOL surgery techniques were analyzed in 3597 participants in a nationwide aggregated electronic health care database using 2-sample independent t tests. Rates of postoperative rhegmatogenous retinal detachment (RRD) after secondary IOL surgery were assessed using chi-square test of proportion. Postoperative visual acuity (VA) was assessed using 2-sample independent t tests. MAIN OUTCOME MEASURES: The primary outcome was change in IOL technique over time. Secondary data points examined were the development of postoperative RRD after secondary IOL surgery, VA changes, the development of endophthalmitis, suture erosion, haptic erosion, or corneal edema after IOL surgery. RESULTS: Anterior chamber IOL use decreased over the 7-year period from 93% of cases to 36% of cases (P < 0.0001), while SFIOL use increased from 3% to 34% (P < 0.0001) and SSIOL use increased from 4% to 30% (P < 0.0001). Visual acuity increased for each surgical technique (ACIOL: 44.1 vs. 49.2 ETDRS letters, P < 0.001; SFIOL: 48.7 vs. 57.6 letters, P < 0.001; SSIOL: 51.5 vs. 61.2 letters, P < 0.001), with larger VA gains seen in SFIOL and SSIOL use (ACIOL vs. SFIOL, P = 0.004; ACIOL vs. SSIOL, P = 0.002; SFIOL vs. SSIOL, P = 0.64). Average RRD rates did not significantly differ between techniques. Rates of endophthalmitis, haptic erosion, and suture erosion were low and did not significantly differ between techniques. Rates of corneal edema were significantly higher in ACIOL cases (vs. SFIOL, P < 0.0001; vs. SSIOL, P < 0.0001). CONCLUSIONS: Rates of ACIOL implantation performed by vitreoretinal surgeons have decreased over time with more vitreoretinal surgeons electing to place either an SFIOL or SSIOL toward the end of the study period; complication profiles among the 3 techniques may be similar. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Association of Metformin and Other Diabetes Medication Use and the Development of New-Onset Dry Age-Related Macular Degeneration: A Case-Control Study.

Purpose: To investigate if metformin use is associated with decreased odds of developing new non-neovascular ("dry") age-related macular degeneration (AMD). Methods: Case-control study examining 194,135 cases with diagnoses of new-onset AMD between 2008 and 2017 and 193,990 matched controls in the Merative MarketScan Research Databases. The diabetic subgroup included 49,988 cases and 49,460 controls. Multivariable conditional logistic regressions identified the risks of exposures on the development of dry AMD. Main outcome measures were odds ratios (ORs) of developing dry AMD with metformin use. Results: In multivariable conditional logistic regression, any metformin use was associated with decreased odds of developing dry AMD (OR = 0.97; 95% confidence interval [CI], 0.95-0.99). This protective effect was noted for cumulative 2-year doses of metformin of 1 to 270 g (OR = 0.93; 95% CI, 0.90-0.97) and 271 to 600 g (OR = 0.92; 95% CI, 0.89-0.96). In a diabetic subgroup, metformin use below 601 g per 2 years decreased the odds of developing dry AMD (1-270 g: OR = 0.95; 95% CI, 0.91-0.99; 271-600 g: OR = 0.92; 95% CI, 0.89-0.96). Unlike in diabetic patients with diabetic retinopathy, diabetic patients without diabetic retinopathy had decreased odds of developing dry AMD with any metformin use (OR = 0.97; 95% CI, 0.94-0.998) and cumulative two-year doses of 1 to 270 g (OR 0.96; 95% CI, 0.91-0.998) and 271 to 600 g (OR = 0.92; 95% CI, 0.88-0.96). Conclusions: Metformin use was associated with decreased odds of developing dry AMD. The protective effect was observed for cumulative 2-year doses below 601 g. In diabetics, this association persisted, specifically in those without diabetic retinopathy. Therefore, metformin may be a strategy to prevent development of dry AMD.

Androstadienone sensitivity is associated with attention to emotions, social interactions, and sexual behavior in older U.S. adults.

Δ 4,16-androstadien-3-one (androstadienone) is a putative human pheromone often linked to sexual attraction in young adults, although specific associations with sexual behavior are not yet established. Androstadienone also serves a broader social-emotional function beyond the sexual domain, specifically tuning the brain to efficiently process emotional information. Whether these effects persist throughout the lifespan into post-reproductive life is unknown. In a laboratory study of older adults, those with greater androstadienone odor sensitivity paid greater attention to subliminal emotional information, specifically, angry faces (p = 0.05), with a similar relationship to happy faces. In contrast, the physical odor n-butanol (a control) did not affect emotional attention (p = 0.49). We then extended this laboratory research and determined whether sensitivity to androstadienone affects the everyday lives of older adults by measuring their social and sexual behavior. In this second study, we surveyed in a nationally representative sample of US older adults living in their homes (National Social Life and Aging Project, 62-90 years; n = 2,086), along with their sensitivity to androstadienone, general olfactory function, health and demographics. Greater sensitivity to androstadienone was associated with richer social lives: having more friends, increased communication with close friends and family, and more participation in organized social events and volunteer activities (all p's ≤ 0.05, generalized linear models, adjusted for age and gender). It was also associated with more recent sexual activity, more frequent sexual thoughts, and viewing sex as an important part of life (all p's ≤ 0.05). General olfactory function did not explain these associations, supporting a specialized function for this pheromone during everyday life, and expanding its role to social life as well as sexual behavior, likely mediated by enhanced attention to emotional information.