The Association between the Body Mass Index and the Incidence of Depression in Korean Adults: Result from the Korean Longitudinal Study

BACKGROUND: Several conflicting studies exist on the relationship between body mass index (BMI) and depression. We investigated the effect of BMI on the development of depression in adults aged 45 years and older using the Korean Longitudinal Study of Aging Study (KLoSA).METHODS: The data from the wave 1 (2006), wave 2 (2008), wave 3 (2010), wave 4 (2012), and wave 5 (2014) database of the Korean Longitudinal Study on Aging (KLoSA) were analyzed. Depression was assessed using the Center for Epidemiologic Studies Depression Scale-10. To investigate the relationship between BMI and depression, ANOVA and chi-square test was used. Kaplan-Meier survival curves were generated, and Cox proportional hazard regression modeling was used to estimate the risk of depression according to obesity status, by controlling for age, sex, and health-related, lifestyle, and socioeconomic variables.RESULTS: This study included 6,811 individuals who were not found to have depression in the first survey. The incidence of depression was the highest in the underweight group (underweight, 74.3%; normal, 63.1%; overweight, 59.5%; obese, 63.0%; severe obese, 59.9%, P < 0.001). The risk of depression was significantly lower in the overweight and severe obese groups than in the underweight group after adjusting for age, sex, and demographic, social, and physical factors (overweight: hazard ratio [HR]=0.872, 95% confidence interval [CI]=0.775–0.981; severe obese: HR=0.791, 95% CI=0.648–0.966).CONCLUSION: The incidence of depression was the highest in the underweight group. The risk of depression was higher in the underweight group than in the overweight and severe obese groups.

Comparison of Cytotoxic Effects on Rabbit Corneal Endothelium between Preservative-free and Preservative-containing Dorzolamide/timolol

PURPOSE: To evaluate and compare the toxic effects of eyedrops containing a fixed combination of 2.0% dorzolamide and 0.5% maleate timolol with or without preservatives on rabbit corneal endothelium. METHODS: This study was performed with 22 eyes of New Zealand white rabbits. Dorzolamide/timolol eyedrops with preservative (Cosopt group) or without preservative (Cosopt-S group) were diluted with a balanced salt solution at a 1 : 1 ratio. We injected 0.1 mL of diluted Cosopt into the anterior chamber of left eyes and an equal volume of diluted Cosopt-S into the anterior chamber of right eyes. Corneal thickness, corneal haze, and conjunctival injection were measured before and 24 hours after treatment. Endothelial damage was compared between both eyes by vital staining (alizarin red/trypan blue staining), live/dead cell assay, TUNEL assay, and scanning electron microscopy. RESULTS: Corneal endothelial damage was severe in the Cosopt group. Cosopt-treated eyes exhibited remarkable corneal edema and prominent apoptosis of endothelial cells. In addition, the live/dead cell assay revealed many dead cells in the endothelium, and scanning electron microscopy analysis showed that corneal endothelial cells exhibited a partial loss of microvilli on the surface as well as extensive destruction of intercellular junctions. However, in the Cosopt-S group, corneal edema was mild and the damage to the corneal endothelium was minimal. CONCLUSIONS: The main cause of corneal endothelial toxicity was due to the preservative in the dorzolamide/timolol fixed combination eyedrops, and not the active ingredient. Thus, it appears to be safer to use preservative-free eyedrops during the early postoperative period.

Effects of Argon Laser Iridotomy on the Corneal Endothelium of Pigmented Rabbit Eyes

PURPOSE: In Asian countries, laser iridotomy for the treatment of angle-closure glaucoma is a common cause of bullous keratopathy, which may be associated with a shallow anterior chamber and dark iris pigmentation in Asians. Several cases of corneal decompensation after argon laser iridotomy have been reported. In the present study, we evaluated the harmful effects of argon laser iridotomy on the corneal endothelium. METHODS: Argon laser iridotomy was performed on the right eyes of pigmented rabbits. Changes in corneal thickness and endothelial cell density after laser iridotomy were evaluated. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was performed for assessment of corneal endothelial cell apoptosis. Combined staining with alizarin red and trypan blue, as well as a live/dead cell assay, were performed for evaluation of damage to the corneal endothelium induced by laser iridotomy. RESULTS: Corneal thickness did not change immediately after laser iridotomy; however, a significant increase was observed 24 hours after iridotomy (p = 0.001). The endothelial cell density of laser-treated eyes four days after laser iridotomy was significantly decreased compared with control eyes (p < 0.001). TUNEL staining showed many TUNEL-positive cells in the corneal endothelium and corneal stroma. No endothelial trypan blue-stained cell nuclei were observed after laser iridotomy; however, several large endothelial cells with damaged membrane integrity were observed. The live/dead cell assay clearly showed a large number of dead cells stained red in several areas throughout the entire corneal button 24 hours after iridotomy. CONCLUSIONS: Argon laser iridotomy induces corneal endothelial cell apoptosis in pigmented rabbit eyes, resulting in decreased endothelial cell density.

Effects of Argon Laser Iridotomy on the Corneal Endothelium of Pigmented Rabbit Eyes

PURPOSE: In Asian countries, laser iridotomy for the treatment of angle-closure glaucoma is a common cause of bullous keratopathy, which may be associated with a shallow anterior chamber and dark iris pigmentation in Asians. Several cases of corneal decompensation after argon laser iridotomy have been reported. In the present study, we evaluated the harmful effects of argon laser iridotomy on the corneal endothelium. METHODS: Argon laser iridotomy was performed on the right eyes of pigmented rabbits. Changes in corneal thickness and endothelial cell density after laser iridotomy were evaluated. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) was performed for assessment of corneal endothelial cell apoptosis. Combined staining with alizarin red and trypan blue, as well as a live/dead cell assay, were performed for evaluation of damage to the corneal endothelium induced by laser iridotomy. RESULTS: Corneal thickness did not change immediately after laser iridotomy; however, a significant increase was observed 24 hours after iridotomy (p = 0.001). The endothelial cell density of laser-treated eyes four days after laser iridotomy was significantly decreased compared with control eyes (p < 0.001). TUNEL staining showed many TUNEL-positive cells in the corneal endothelium and corneal stroma. No endothelial trypan blue-stained cell nuclei were observed after laser iridotomy; however, several large endothelial cells with damaged membrane integrity were observed. The live/dead cell assay clearly showed a large number of dead cells stained red in several areas throughout the entire corneal button 24 hours after iridotomy. CONCLUSIONS: Argon laser iridotomy induces corneal endothelial cell apoptosis in pigmented rabbit eyes, resulting in decreased endothelial cell density.