Global Vision Impairment Due to Uncorrected Presbyopia

Objectives: To evaluate the personal and community burdens of uncorrected presbyopia. Methods: We used multiple population-based surveys to estimate the global presbyopia prevalence, the spectacle coverage rate for presbyopia, and the community perception of vision impairment caused by uncorrected presbyopia. For planning purposes, the data were extrapolated for the future using population projections extracted from the International Data Base of the US Census Bureau. Results: It is estimated that there were 1.04 billion people globally with presbyopia in 2005, 517 million of whom had no spectacles or inadequate spectacles. Of these, 410 million were prevented from performing near tasks in the way they required. Vision impairment from uncorrected presbyopia predominantly exists (94%) in the developing world. Conclusions: Uncorrected presbyopia causes widespread, avoidable vision impairment throughout the world. Alleviation of this problem requires a substantial increase in the number of personnel trained to deliver appropriate eye care together with the establishment of sustainable, affordable spectacle delivery systems in developing countries. In addition, given that people with presbyopia are at higher risk for permanently sight-threatening conditions such as glaucoma and diabetic eye disease, primary eye care should include refraction services as well as detection and appropriate referral for these and other such conditions

Trauma history and depression predict incomplete adherence to antiretroviral therapies in a low income country.

As antiretroviral therapy (ART) for HIV becomes increasingly available in low and middle income countries (LMICs), understanding reasons for lack of adherence is critical to stemming the tide of infections and improving health. Understanding the effect of psychosocial experiences and mental health symptomatology on ART adherence can help maximize the benefit of expanded ART programs by indicating types of services, which could be offered in combination with HIV care. The Coping with HIV/AIDS in Tanzania (CHAT) study is a longitudinal cohort study in the Kilimanjaro Region that included randomly selected HIV-infected (HIV+) participants from two local hospital-based HIV clinics and four free-standing voluntary HIV counselling and testing sites. Baseline data were collected in 2008 and 2009; this paper used data from 36 month follow-up interviews (N = 468). Regression analyses were used to predict factors associated with incomplete self-reported adherence to ART. INCOMPLETE ART ADHERENCE WAS SIGNIFICANTLY MORE LIKELY TO BE REPORTED AMONGST PARTICIPANTS WHO EXPERIENCED A GREATER NUMBER OF CHILDHOOD TRAUMATIC EVENTS: sexual abuse prior to puberty and the death in childhood of an immediate family member not from suicide or homicide were significantly more likely in the non-adherent group and other negative childhood events trended toward being more likely. Those with incomplete adherence had higher depressive symptom severity and post-traumatic stress disorder (PTSD). In multivariable analyses, childhood trauma, depression, and financial sacrifice remained associated with incomplete adherence.\ud This is the first study to examine the effect of childhood trauma, depression and PTSD on HIV medication adherence in a low income country facing a significant burden of HIV. Allocating spending on HIV/AIDS toward integrating mental health services with HIV care is essential to the creation of systems that enhance medication adherence and maximize the potential of expanded antiretroviral access to improve health and reduce new infections

The global prevalence of dry eye disease: A Bayesian view

Purpose: To provide estimates for the prevalence of dry eye disease globally and in sub-groups defined by: diagnostic criterion, sex, geographic location and age, using a Bayesian approach. Methods: Modelling prevalence as a Beta distribution, estimates were inferred from Bayesian posterior distributions obtained by combing an uninformed prior with likelihood functions generated from all relevant studies reporting dry eye prevalence between 1997 and 2021. Results: Global prevalence of dry eye disease was estimated at 11.59% (standard deviation (SD) = 0.04). For symptomatic disease, the estimate was 9.12% (SD = 0.04), with women 9.5% (SD = 0.05) and men 6.8% (SD = 0.06); prevalence was lowest in North America, 4.6% (SD = 0.03) and highest in Africa, 47.9% (SD = 1.8). For signs, prevalence was 35.2% (SD = 0.3), with woman 34.7% (SD = 0.7) and men 37.6% (SD = 0.7); North America showed the lowest regional prevalence, 3.5%, (SD = 0.4) with Eastern Asia the highest, 42.8% (SD = 0.4). Using TFOS DEWS II diagnostic criteria resulted in a global prevalence of 29.5% (SD = 0.8), with women 28.1% (SD = 1.2) and men 24.9% (SD = 1.4). Prevalence was lowest during the fifth decade, increasing approximately linearly with age thereafter. Estimates for other categories are given in accompanying tables. Conclusion: A simple, flexible, yet powerful means of combining data from multiple sources to yield prevalence estimates across a range of circumstances is described, that is compatible with published guidelines for conducting meta-analysis. Estimates can be readily updated as new information emerges, or according to need. Understanding the specific characteristics of studies chosen for inclusion is critical to the validity of the outcome. Although dry eye disease is evidently common, affecting about one in 11 people world-wide, data are sparse for the young and all geographical locations except Eastern Asia

Filaggrin Expression in the Lid Margin During Contact Lens Wear.

AIM: To investigate the expression of the keratinization-related protein, filaggrin, in the lid margin epithelium of contact lens (CL) wearers compared with nonwearers. METHODS: This was a cross-sectional study of 100 individuals with different exposures to CL wear: short, moderate, and long experience; previous CL wearers; and nonwearers as controls. Impression cytology samples were collected from the lid wiper (LW) area of the central upper lid margin. After fixing, an equal, random sample was selected from each group (n=13) for immunocytochemistry analysis using antihuman primary anybody (mouse filaggrin), then stained with secondary antibody (fluorescein isothiocyanate-conjugated donkey anti-mouse immunoglobulin G horseradish peroxidase) to detect filaggrin. Imaging was performed with the 3i-Vivo 2-photon microscope equipped with a Zeiss 20×-objective and SlideBook-reader software. RESULTS: Sixty-five samples from 65 participants (37 women; mean age±SD: 25.1±4.1 years) were collected. Filaggrin was detected in all 65 randomly selected immunostained marginal epithelium samples. All samples were similar in showing patchy areas of filaggrin immunostaining, regardless of CL wear, symptoms or epithelium morphology. Because the filaggrin immunostaining showed similar patterns across almost all the observed samples, comparison between subject groups was impractical. The presence of filaggrin in the healthy LW was additionally confirmed by an independent laboratory. CONCLUSION: Filaggrin expression seems to be a normal part of epithelial cell differentiation in the lid margin and may not be a useful keratinization/stress biomarker in the marginal epithelium. Investigating other keratinization biomarkers that are not detected in the normal mucocutaneous junction/LW may help to understand the keratinization nature of LW epithelium changes in CL wearers

Photobiomodulation (low-level light therapy) and dry eye disease

Dry eye disease is one of the most common, chief-complaints presenting in clinical practice, with a prevalence of up to 50%. Evaporative dry eye, as a result of meibomian gland dysfunction, is thought to be the biggest component factor. Treatments for meibomian gland dysfunction aim to restore tear film homoeostasis and include warm compress therapy, eyelid hygiene, in-office meibomian gland expression and lipid-containing, artificial tears. A recent introduction to the in-office treatments available for meibomian gland dysfunction has been low-level light therapy, also known as photobiomodulation. The technique involves applying red, or near infra-red, radiation using low-power light sources and is suggested to promote tissue repair, decrease inflammation, and relieve pain. This work aims to review the available literature on the efficacy and safety of photobiomodulation in meibomian gland dysfunction and dry eye disease, as well as what is currently known about its mechanism of action

Temporal considerations in contact lens discomfort

Purpose: To determine the relative contributions to perceived discomfort during contact lens wear of contact time with the lens and the time of day at which wear begins, using a wearing framework similar to that of regular users. Methods: Twenty-three participants reported ocular discomfort using a 1–100 visual analogue rating scale, when prompted by email, during one day without contact lenses and on three other days while wearing soft contact lenses for twelve hours. Contact lens wear began at a different time on each day. The effect of start time on the change in discomfort during the wearing period was evaluated. Results: The average (± 95 % CI) change in discomfort over 12 h without contact lenses was -0.3 ± 3.5. The corresponding values during contact lens wear were 23.5 ± 14.6 when starting wear before 8am, 16.8 ± 11.0 when starting between 8am & 10am and 22.7 ± 8.4 when starting after 10am. While the increased discomfort was significant irrespective of start time (p < 0.01), there were no statistically significant differences between start times (p = 0.98). Conclusion: Discomfort during contact lens wear is associated with the length of time lenses are on-eye but not with the time of day when lenses are placed on-eye. This relationship is variable in the population and does not, of itself, explain why contact lenses become uncomfortable during wear. Active monitoring of participant compliance should be a consideration in all studies involving time critical responses