Ocular abnormalities in morbid obesity

24-H movement behaviors and visual impairment among Chinese adolescents with and without obesity

BACKGROUND

Previous studies have identified obesity, sleep patterns, screen time, and physical activity as independent risk factors for the visual health of adolescents. However, our understanding of how these factors interact and contribute to visual impairment remains limited. This study aimed to investigate the relationship between adherence to the 24-h movement guidelines (24-HMG) and visual impairment in adolescents with and without obesity.

METHODS

We analyzed data from the 2014-2015 China Education Panel Survey. Participants provided self-reported information on their screen time, sleep duration, and physical activity levels. The data on weight, height, and visual acuity were obtained from school health examination reports. Logistic regression analysis was conducted to assess the association between 24-h movement behaviors and visual impairment, reported as odds ratios (ORs) with a 95 % confidence interval (CI).

RESULTS

After controlling for covariates such as sex and age, it was found that adolescents with obesity who adhered to the sleep guidelines had a lower risk of visual impairment compared with adolescents without obesity who did not adhere to the 24-HMG (OR = 0.84, 95 % CI: 0.75-0.94, P = 0.003). Additionally, adolescents who adhered to both the physical activity and sleep guidelines had an even lower risk of visual impairment (OR = 0.58, 95 % CI: 0.42-0.79, P = 0.001).

CONCLUSIONS

Adhering to the Sleep and physical activity + Sleep recommendations in the 24-HMG could significantly reduce the risk of visual impairment in adolescents without obesity. No significant relationship was observed between adherence to 24-HMG and the risk of visual impairment in adolescents with obesity.

Impaired brachial flow-mediated dilation may predict choroidal and retinal nerve fibre layer thickness changes in people with obesity

CLINICAL RELEVANCE

Choroidal thickness and peripapillary retinal nerve fibre layer (RNFL) changes are known to occur in obesity. Endothelial dysfunction and systemic atherosclerosis may play a role in the pathophysiology of these differences.

BACKGROUND

Flow-mediated dilation (FMD) is reduced in patients with endothelial dysfunction, and the ankle-brachial index is a surrogate marker for atherosclerosis. This study was conducted to examine the relationship between systemic vascular parameters (FMD, and ankle-brachial index), subfoveal choroidal thickness, and peripapillary RNFL thickness in obese individuals.

METHODS

This observational, cross-sectional study involved 108 total participants who were divided into two groups. One group consisted of 54 obese subjects who each had a body mass index of 30 kg/m2 or more. The other control group contained 54 participants who each had a body mass index of 25 kg/m2 or less but higher than 20 kg/m2 . For each participant, only one eye was examined in this study. Subfoveal choroidal thickness, RNFL thickness, ankle-brachial index, and ultrasound measurement of the brachial artery FMD were performed. FMD was categorised according to receiver operating characteristic analysis, and endothelial dysfunction was defined as an FMD ≤ 7.29%.

RESULTS

Subfoveal choroidal and RNFL thicknesses in the temporal quadrant were significantly lower in the obese group (p < 0.05). Lower mean values of subfoveal choroidal and RNFL thicknesses in the temporal and inferior quadrants were observed in subjects with an FMD ≤ 7.29% (p < 0.05). In people with obesity, FMD was positively correlated with subfoveal choroidal thickness (r = 0.322, p = 0.001), inferior RNFL thickness (r = 0.259, p = 0.007), and temporal RNFL thickness (r = 0.297, p = 0.002). However, the ankle-brachial index was not correlated with obesity.

CONCLUSIONS

Impaired FMD was associated with reduced subfoveal choroidal and RNFL thicknesses in the temporal and inferior quadrants of people with obesity.

Role of excessive weight in intraocular pressure: a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis aimed to analyse the effect of excess body weight on intraocular pressure (IOP) values.

METHOD AND ANALYSIS

A literature search from PubMed, Medline and ScienceDirect Databases on 18 May 2023 was conducted by three reviewers, then filtered each study based on inclusion and exclusion criteria. For the quality assessment of included studies, the Newcastle-Ottawa Scale was adapted. Meta-analysis was performed using RevMan V.5.4 by entering the IOP values of each group to measure the mean difference.

RESULTS

From 2656 studies, there were 9 studies that matched the criteria and then were included to perform a quantitative meta-analysis. The results showed a mean difference of 0.93 (95% CI: 0.67 to 1.18) of the excessive weight group against the normal weight group. This suggests that there is a significant relationship between excess body weight and increasing values of IOP.

CONCLUSION

It can be concluded that excessive body weight tends to lead to higher IOP, which means that high IOP becomes a major risk factor for glaucoma.

How Does Weight Loss After Bariatric Surgery Impact the Ocular Parameters? A Review

Our review aimed to assess the effects of bariatric surgery-induced weight loss on ocular functions. We focused on retinochoroidal microcirculation, glaucomatous factors, and the condition of the eye surface pre- and postoperatively. The review covered 23 articles, including five case reports. Bariatric surgery positively impacts retinochoroidal microcirculation. The arterial perfusion and vascular density improve, venules constrict, and the arteriole-to-venule ratio increases. Weight loss positively correlates with intraocular pressure decrease. The impact of postoperative weight loss on the choroidal thickness (CT) and the retinal nerve fiber layer (RNFL) is still unclear. The correlation between ocular symptoms and hypovitaminosis A needs to be evaluated. Further research is required, especially regarding CT and RNFL, mainly focusing on long-term follow-up.

Associations between Body Mass Index and Choroidal Thickness, Superficial and Deep Retinal Vascular Indices, and Foveal Avascular Zone measured by OCTA

AIM

The present study explores the effects of Body Mass Index (BMI) on choroidal thickness, the deep and superficial retinal capillary plexuses, and the foveal avascular zone (FAZ).

METHODS

The subjects in this prospective study were divided into five groups based on their calculated BMI. Choroidal thickness, superficial and deep retinal capillary plexuses, and FAZ were measured using enhance depth imaging (EDI) and optical coherence tomography angiography (OCTA). The groups were then compared and correlations with BMI were evaluated.

RESULTS

The study included 210 eyes of 105 subjects. The comparison of the BMI groups revealed a significant decrease in the mean choroidal thicknesses in the obese groups (p = 0.001), and a significant negative correlation between BMI and mean choroidal thickness (p = 0.02). The results of the analysis of the mean superficial and deep retinal capillary plexuses did not differ between the groups (p = 0.089, p = 0.808 respectively), while the deep FAZ measurements revealed a significant decrease in the obese groups (p = 0.003).

CONCLUSION

Choroidal thickness and deep FAZ are significantly negatively correlated with BMI, suggesting potential choroidal and retinal microvascular effects of obesity.

Obesity-induced ocular changes in children and adolescents: A review

Childhood obesity has reached epidemic levels worldwide. Overweight and obesity is associated with an increase in several inflammatory markers, leading to chronic low-grade inflammation responsible for macro- and microvascular dysfunction. While the impact of obesity on overall health is well-described, less is known about its ocular manifestations. Still, there are few studies in children and adolescents in this regard and they are inconsistent. However, some evidence suggests a significant role of overnutrition in the development of changes in retinal microvasculature parameters (wider venules, narrower arterioles, lower arteriovenous ratio). Higher values of intraocular pressure were found to be positively correlated with high body mass index (BMI) as well as obesity. In addition, the retinal nerve fiber layer (RNFL) values seem to be lower in obese children, and there is a significant negative correlation between RNFL values and anthropometric and/or metabolic parameters. Changes also could be present in macular retinal thickness and choroidal thickness as well as in the retinal vessel density in children with obesity. However, these associations were not consistently documented. The purpose of this review is to present the most current issues on child obesity and the related potential ocular effects through an overview of international publications from the years 1992-2022.

Evaluation of the alteration in retinal features following bariatric surgery in patients with morbid obesity

Aim: The aim of the study is to evaluate the effect of bariatric surgery on the retina and choroid in non-diabetic and non-hypertensive patients with morbid obesity using optic coherence tomography (OCT) retrospectively. Material and Method: Seventy-four eyes of seventy-four patients who have been underwent sleeve gasterectomy for morbid obesity in Balıkesir University Medicine Faculty & February 2019 and November 2020 were evaluated. All participants has a detailed ophthalmologic examination including best-corrected visual acuity (BCVA), intraocular pressure (IOP), slit-lamp biomicroscopy, retinal examination through non-dilated pupil via 90 D fundus lens, the retinal thickness (central, perifoveal, and parafoveal superior/nasal/inferior/temporal quadrants), and choroidal thickness through optic coherence tomography (RTVue XR Avanti, Optovue) in immediate preoperative and postoperative sixth-month. All values were compared. Results: The macular thickness was increased significantly in all quadrants in postoperative visits (p0.05). The correlation between preoperative BMI and preoperative choroidal thickness was significant (R: 0.416, p

Spectral-domain OCT measurements in obesity: A systematic review and meta-analysis

Background

Previous studies proposed possible applications of spectral-domain optical coherence tomography (SD-OCT) measurements in prognosticating pathologies observed in overweight/obesity, including ocular, vascular, and neurologic consequences. Therefore, we conducted a systematic review and meta-analysis to investigate the changes in the in SD-OCT measurements of the patients with higher body mass index (BMI) compared to normal weight individuals.

Materials and methods

We conducted a systematic search on PubMed, Scopus, and Embase. The search results underwent two-phase title/abstract and full-text screenings. We then analyzed SD-OCT measurements differences in patients with high BMI and controls, and performed meta-regression, sub-group analysis, quality assessment, and publication bias assessment. The measurements included macular thickness, cup to disc ratio, ganglion cell-inner plexiform layer (GC-IPL) and its sub-sectors, RNFL and peripapillary RNFL (pRNFL) and their sub-layers, and choroidal thickness and its sub-sectors.

Results

19 studies were included in this meta-analysis accounting for 1813 individuals, 989 cases and 824 controls. There was an overall trend towards decreased thickness in high BMI patients, but only two measurements reached statistical significance: temporal retinal nerve fiber layer (RNFL) (Standardized mean difference (SMD): -0.33, 95% confidence interval (CI): -0.53 to -0.14, p<0.01) and the choroidal region 1.0 mm nasal to fovea (SMD: -0.38, 95% CI: -0.60 to -0.16, p<0.01).

Conclusion

Some ocular layers are thinner in patients with higher BMI than the controls. These SD-OCT measurements might correlate with adverse events related to increased body weight and have prognostic abilities. As SD-OCT is a robust, rapid and non-invasive tool, future guidelines and studies are needed to evaluate the possibility of their integration into care of the patients with obesity.

Evaluation of the impact of childhood obesity on retrobulbar hemodynamics and retinal microvasculature

OBJECTIVE

To evaluate changes in retrobulbar ocular blood flow parameters by using Colour Doppler Imaging (CDI) and changes in foveal microvasculature by using Optical Coherence Tomography Angiography (OCTA) in pediatric obese patients and to compare them with a group of healthy children.

METHODS

Children diagnosed with obesity without hypertension and diabetes (39 subjects, obese group) and age-matched healthy controls (26 subjects, control group) underwent CDI and OCTA imaging. Peak systolic velocity, end-diastolic velocity and resistivity index from ophthalmic, central retinal and posterior ciliary arteries on CDI; superficial and deep capillary plexus vascular density and foveal avascular zone area on OCTA imaging were obtained in each group. Central foveal and subfoveal choroidal thicknesses were also measured. CDI and OCTA parameters were compared between two groups.

RESULTS

Peak systolic and end-diastolic velocities were found to be significantly lower in obese children than in controls in all three examined arteries (p < 0.05). Resistivity index values were similar between the groups. OCTA imaging did not reveal significant changes in superficial and deep capillary plexus vascular densities and foveal avascular zone area across analysed retinal regions between the groups. Subfoveal choroid was thicker in obese group than in control group (325.89 ± 52.77 µm vs. 304.52 ± 21.76 µm, p = 0.04).

CONCLUSION

An apparent decrease was present in retrobulbar hemodynamics in obese children. This arises the possibility of early ocular macrovascular compromise rather than retinal microvascular impairment in childhood obesity.

Is there any connection between choroidal thickness and obesity?

Obesity is a health-threatening and epidemic medical condition that can affect individuals of different ages and is potentially associated with an increased risk of systemic and ocular disorders. Despite the well-documented adverse effects of obesity on different parts of the body vasculature, less published data are available concerning obesity-related consequences on the ocular vasculature. As the human choroid is a highly vascularized tissue, its morphology and function might be altered in obese individuals. The micro-structural changes within the choroid could also trigger development of subsequent functional abnormalities of the eye. Previous population-based studies have asserted an association between obesity and choroidal thickness; however, they reported conflicting patterns of association between obesity and changes in choroidal thickness. Therefore, to enhance our understanding of the changes in choroidal morphology secondary to obesity, we reviewed studies describing the micro-structural consequences of obesity on the choroidal thickness profile and its underlying physiological and anatomical basis. This review includes all original publications related to the association between choroidal thickness and obesity published until mid-2021 that were indexed in PubMed, Google Scholar, ScienceDirect, or Scopus.

Evaluation of the choroidal thickness and retinal nerve fiber layer and visual fields in morbid obesity: Does bariatric surgery affect retinal structure and function?

Purpose

The study aimed to investigate the changes in choroidal thickness (CT), retinal nerve fiber layer thickness (RNFL), and visual field parameters in morbidly obese patients following bariatric surgery.

Methods

The study included 40 morbidly obese patients with body mass indexes (BMI) ≥40 who had undergone bariatric surgery (Group 1) and 40 age-and sex-matched healthy subjects with normal BMI values (Group 2). RNFL and CT measurements by optical coherence tomography (OCT) and visual field test were performed preoperatively and the 1^st, 6^th, and 12th months postoperatively. CT measurements were obtained from the subfoveal, nasal (N), and temporal (T) regions at distances of 500 μm and 1,000 μm from the fovea.

Results

No significant pathology was detected during ophthalmological examinations following bariatric surgery. The BMIs were found to be significantly lower in all of the periods after bariatric surgery (P < 0.0001). The CT measurements decreased significantly in all periods after bariatric surgery (P < 0.0001). No differences were found in terms of the mean RNFL thicknesses in all postoperative periods (P = 0.125). Visual field tests showed no significant changes during scheduled visits. (P = 0.877). No visual field defect was detected in any patient during the follow-up periods after bariatric surgery.

Conclusion

These results have suggested that CT is positively correlated with BMI and decreased with a reduction in BMI progressively. Nutritional disorders resulting from malabsorption have not caused any nutritional optic neuropathy and visual field defect for at least the first postoperative year after bariatric surgery.

The protective roles of clusterin in ocular diseases caused by obesity and diabetes mellitus type 2

Obesity is a chronic, non-transmissible and multifactorial disease commonly associated with systemic inflammation and damage to health. This disorder has been pointed out as leading to the development of a diversity of eye diseases and, consequently, damage to visual acuity. More specifically, cardiometabolic risk is associated with lacrimal gland dysfunctions, since it changes the inflammatory profile favoring the development and worsening of dry eye disease. In more severe and extreme cases, obesity, inflammation, and diabetes mellitus type 2 can trigger the total loss of vision. In this scenario, besides its numerous metabolic functions, clusterin, an apolipoprotein, has been described as protective to the ocular surface through the seal mechanism. Thus, the current review aimed to explain the role of clusterin in dry eye disease that can be triggered by obesity and diabetes.

Subfoveal choroidal thickness and peripapillary retinal nerve fiber layer thickness in young obese males

OBJECTIVE

Regarding the effect of obesity on subfoveal choroidal thickness (CT) and peripapillary retinal nerve fiber layer (RNFL) thickness, controversial results have been reported in different patient groups. This study aimed to evaluate the effect of obesity on these parameters among young male subjects in comparison with age-matched non-obese healthy males.

METHODS

This prospective, cross-sectional study included both eyes of 50 obese young males and 50 healthy non-obese young males. The obese and the non-obese groups included subjects with a BMI of ⩾30 and ⩽25 kg/m², respectively. Subfoveal choroidal thickness and RNFL analyses were conducted by spectral domain optical coherence tomography (SD-OCT).

RESULTS

Subfoveal choroidal thickness (321.0 ± 46.7 vs 338.4±35.3, p = 0.002) and RNFL thickness at temporal quadrant (73.4 ± 9.9 vs 76.4 ± 9.3, p = 0.008) was significantly lower in the obese group when compared to the non-obese group. The groups did not differ regarding peripapillary RNFL thickness at other quadrants (superior, inferior, or nasal) or regarding mean peripapillary RNFL thickness.

CONCLUSION

Findings of this study demonstrated a negative correlation of obesity with subfoveal choroidal thickness and temporal quadrant peripapillary RNFL thickness. Larger studies on different patient groups with longer-term follow-up are warranted to better elucidate the ophthalmological effects of obesity.

Evaluation of the subfoveal choroidal and outer retinal layer thickness in obese women

CLINICAL RELEVANCE

Obesity has become one of the most important health problems of today with its increasing prevalence. With the development of retinal imaging systems, obesity has been observed to be associated with changes in outer retinal layers and choroid in women.

BACKGROUND

The aim of this study was to examine retinal layer parameters and their relationship with body mass index in obese women.

METHODS

The study included 197 eyes of 197 women, of whom 44 were normal-weight, 40 were overweight, 40 were class 1 obese, 38 were class 2 obese, and 35 were morbidly obese. The thickness of the choroid was measured manually using an enhanced-depth imaging optical coherence tomography scanning program.

RESULTS

The mean choroidal thickness values in five locations were lower than those of normal-weight, overweight, class 1, and class 2 obese women, in morbidly obese women (p < 0.05 for all). Subfoveal outer retinal layer thickness and specific sublayer thickness of the photoreceptor layer values were significantly lower in morbidly obese women than in normal-weight women, but there were no statistically significant differences between the groups in retinal pigment epithelium thickness and Bruch's membrane thickness (p = 0.001, p < 0.001, p = 1.00, and p = 0.101, respectively). Furthermore, there were significant negative relationships between body mass index and subfoveal choroidal thickness, subfoveal outer retinal layer thickness, and specific sublayer thickness of the photoreceptor layer values (r = -0.327, p < 0.001; r = -0.259, p < 0.001; and r = -0.281, p < 0.001, respectively).

CONCLUSIONS

Morbid obesity was associated with a thinner choroid, subfoveal outer retinal layer, and specific sublayer thickness of the photoreceptor layer in women. Furthermore, retinal hypoxia associated with morbid obesity may be related to a decrease in photoreceptor layer thickness. Thinning of the outer retinal layer may also lead to atrophy of the cone sheath.