Sudan Journal of Medical Sciences Volume 16, Issue no. 4, DOI 10.18502/sjms.v16i4.9942 Production and Hosting by Knowledge E Research Article The Impact of Cataract Surgery on Depression in Elderly Iranian Patients: A Case–Control Study Kiumars Nowroozpoor Dailami1, Mohammad Ali Heidari Gorji2, Seyed Hamzeh Hoseini3, and Asadollah Farookhfar1 1Department of Ophthalmology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran 2Department of Medical–Surgical Nursing, Nasibeh School of Nursing and Midwifery, Mazandaran University of Medical Sciences, Sari, Iran 3Psychiatry and Behavioral Sciences Research Center, Addiction Institute, Mazandaran University of Medical Sciences, Sari, Iran ORCID: Asadollah Farookhfar: https://orcid.org/0000-0002-5584-7423 Abstract Background: Cataract-related vision impairment is clearly associated with depressive symptoms in old age. This study aimed to evaluate the effect of cataract surgery on depression among elderly Iranian patients. Methods: In this case–control study, a total of 113 elderly patients with and without cataract who were admitted to Buali-Sina Hospital in Sari, Mazandaran, Iran were evaluated. Ophthalmological examinations were first performed at the beginning of the study and then four months later; demographic and clinical characteristics were obtained for all patients. Additionally, depression was assessed using the Hospital Anxiety and Depression Scale (HADS) for all patients during the study period. Results: A statistically significant difference was found between the mean depression score in patients without cataract (3.28), patients with cataract surgery (3.74), and patients without cataract surgery (5.60) (P = 0.024). On the other hand, there was no statistically significant differences between the mean depression score in patients with cataract surgery and patients without cataract (P = 0.582). However, a statistically significant difference was observed between the mean depression score after cataract surgery in men (1.70) and women (4.94) (P < 0.001). Visual function improved in all bilateral cataract patients who had surgery in one eye. Also, the results of this study showed that in all unilateral cataract patients who had eye surgery, visual function in the left and right eyes improved. Conclusion: We conclude that depression is more prevalent in patients with cataract compared to those without cataract. In addition, cataract surgery seems to be associated with reduced depression and better visual acuity in elderly patients with cataract. Keywords: depressive disorder, cataract, cataract extraction, aged How to cite this article: Kiumars Nowroozpoor Dailami, Mohammad Ali Heidari Gorji, Seyed Hamzeh Hoseini, and Asadollah Farookhfar (2021) “The Impact of Cataract Surgery on Depression in Elderly Iranian Patients: A Case–Control Study,” Sudan Journal of Medical Sciences, vol. 16, Issue no. 4, pages 439–449. DOI 10.18502/sjms.v16i4.9942 Page 439 Corresponding Author: Asadollah Farookhfar; email: drfarookhfar@yahoo.com Received 20 August 2021 Accepted 08 November 2021 Published 31 December 2021 Production and Hosting by Knowledge E Kiumars Nowroozpoor Dailami et al.. This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited. Editor-in-Chief: Prof. Mohammad A. M. Ibnouf http://www.knowledgee.com mailto:drfarookhfar@yahoo.com https://creativecommons.org/licenses/by/4.0/ https://creativecommons.org/licenses/by/4.0/ Sudan Journal of Medical Sciences Kiumars Nowroozpoor Dailami et al. 1. Introduction Cataract is the most prevalent cause of reversible blindness worldwide. It has been estimated that cataract causes 35% of blindness and 24% of all visual impairment in the world [1, 2]. Globally, cataract surgery is one of the most prevalent surgeries, with 1.7 million surgeries performed in United States per year [3–5]. Despite recent advances in technology, which have significantly improved cataract-related visual impairments [6–8], severe cataract-related disorders have significant negative effects on patients’ quality of life, especially their mental health [9, 10]. It has been previously demonstrated that cataract-related visual impairments are clearly associated with depression in elderly people [10, 11], which is further associated with increased risk of cognitive impairment, disability, and mortality [12–14]. The results of an Australian study showed that 43.4% of elderly people had eye diseases [15]. In addition, it has been shown that depressive symptoms are more common in cataract patients than in patients with other eye diseases [15]. In Iran, although studies in this field are very limited, the results of a study showed that 45.7% of cataract patients had moderate to severe levels of depression [16]. Meanwhile, cataract surgery seems to be effective in treating depression. Many study have revealed that the symptoms of depression can significantly reduce after a cataract surgery [17–19], however, some studies have reported conflicting results. According to a Japanese study, no statistical significance was found in the reduction of depression symptoms in elderly patients after cataract surgery [20]. Additionally, the results of a study in the United States showed that vision improvement after cataract surgery in elderly patients had no significant effect on reducing depression symptoms [21]. Considering the importance of potential negative psychosocial consequences of cataract and conflicting available evidence regarding the effect of cataract surgery on depressive symptom in older people, we aimed to evaluate the impact of cataract surgery on depression among elderly patients. 2. Materials and Methods 2.1. Study design and sample In this case–control study, a total of 68 cataract patients and 45 elderly patients (60 years of age and older) without cataracts who were admitted to Buali-Sina Hospital in Sari, Mazandaran, Iran were evaluated. Data were collected using purposeful sampling. The case group consisted of 36 patients with cataract surgery (19 patients with bilateral DOI 10.18502/sjms.v16i4.9942 Page 440 Sudan Journal of Medical Sciences Kiumars Nowroozpoor Dailami et al. and 17 with unilateral cataract) and 32 cataract patients without surgery (15 patients with bilateral and 17 with unilateral cataract). In addition, the control group consisted of 45 elderly patients without cataract disease. 2.2. Inclusion and exclusion criteria The inclusion criteria were patients with unilateral or bilateral age-related cataracts, diag- nosed by an ophthalmologist, aged ≥60 years, and a visual acuity of <0.4 with glasses. Additionally, patients with neurological diseases such as Alzheimer’s, Parkinson’s, or history of coronary heart disease, traumatic cataracts, and advanced eye diseases such as retinal detachment, strabismus, macular degeneration, diabetic retinopathy, and glaucoma were excluded. 2.3. Data collection Data were collected using two questionnaires, one including demographic and clinical characteristics of the patients (such as age, sex, weight, medication consumption, sup- plemental health insurance, vehicle, occupation, underlying diseases, visual acuity, and presence of refractive error), and other being the Hospital Anxiety and Depression Scale (HADS). The HADS questionnaire was designed to assess the severity of depressive and anxiety symptoms in patients [22]. Validity and reliability of this scale was assessed previously and was good. This self-reporting scale consists of 14 items, with subscales of anxiety (7 items) and depression (7 items), with scores ranging from 0 to 21. Each item consists of a 4-point Likert scale, from a score of 0 to 3. Scores between 0 and 7; 8 and 10; and 11 and 21 were considered as normal state, mild, and severe depression, respectively [23]. All patients were evaluated by an ophthalmologist on the day of admission. Snellen chart, with and without glasses, was used to evaluate the visual acuity of the patients. Also, presence of refractive errors was assessed using retinoscopy. After eye examinations by an optometrist, the HADS questionnaire was completed by participants. During surgery, an intraocular lens was implanted in all patients in the case group. Four months after the cataract surgery, visual acuity and refractive errors were measured and, if necessary, corrective glasses were prescribed. Also, the HADS questionnaire was completed again by patients. All participants in the control group completed the HADS questionnaire during the study period and their visual acuity was measured using a Snellen chart with and without glasses. DOI 10.18502/sjms.v16i4.9942 Page 441 Sudan Journal of Medical Sciences Kiumars Nowroozpoor Dailami et al. 2.4. Statistical analysis Data were analyzed using the Statistical Package for the Social Sciences (SPSS) soft- ware (version 16.0, Chicago, IL, USA). The mean (standard deviation) and the number (percentage) were used to evaluate quantitative and qualitative variables, respectively. The t-test and ANOVA were used to evaluate the main variables of the study. P-value < 0.05 was considered as statistically significant. 3. Results A total of 113 patients, including 68 cataract patients and 45 elderly patients without cataract, were included in the present study. Of the patients with cataract, 42.6% were male and 51.5% were aged 66–70 years (the mean and standard deviation of ages in patients with and without cataract was 69.12 ± 1.83 and 68.51 ± 2.21 years, respectively; P = 0.412). Of the patients without cataracts, 57.8% were male and 68.9% were aged 61– 70 years. Table 1 presents the demographic characteristics of patients with and without cataract. Based on the results of the present study, there was a statistically significant difference between the mean depression scores in patients without cataract (3.28), patients with cataract surgery (3.74), and patients without cataract surgery (5.60) (P = 0.024). On the other hand, there was no statistically significant difference between the mean score of depression in patients with cataract surgery and patients without cataract (P = 0.582). The mean posttest depression score of bilateral cataract patients who had surgery in one eye (3.26) was lower than the mean pretest of the same group before cataract surgery (7.63) (P < 0.001). However, the mean posttest depression of unilateral atacract patients who had eye surgery (4.31) was lower than the mean pretest of the same group before cataract surgery (6.50) (P = 0.005). There was no statistically significant difference between the mean depression of unilateral cataract patients who had eye surgery (4.31) and bilateral cataract patients who had surgery in one eye (3.26) (P = 0.356). Moreover, there was a statistically significant difference between the mean depression of patients with cataract surgery (3.74) and patients without cataract surgery (5.60) (P = 0.187) (Table 2). There was a statistically significant difference between the mean depression of patients without cataract surgery (5.60) and patients without cataract (3.28) (P = 0.031). However, there was no statistically significant difference between the mean depression of patients without cataract in the pretest (2.95) and the posttest (3.28) stages (P = DOI 10.18502/sjms.v16i4.9942 Page 442 Sudan Journal of Medical Sciences Kiumars Nowroozpoor Dailami et al. Table 1: Demographic characteristics of patients with and without cataract (n = 113). Variables Group With cataract Without cataract (n = 68) (n = 45) Age (yr) 60–65 7 (10.3) 10 (22.2) 66–70 35 (51.5) 31 (68.9) >70 26 (38.2) 4 (8.9) Sex Male 29 (42.6) 26 (57.8) Female 39 (57.4) 19 (42.2) Underlying diseases None 47 (69.1) 33 (73.4) Blood pressure 14 (20.6) 8 (17.8) Diabetic 7 (10.3) 4 (8.9) Medication consumption Yes 50 (73.5) 35 (77.8) No 18 (26.5) 10 (22.2) Supplemental health insurance Yes 38 (55.9) 39 (86.7) No 30 (44.1) 6 (13.3) Vehicle Yes 14 (31.1) 31 (68.9) No 53 (77.9) 15 (22.1) Occupation Freelancer 17 (25) 4 (8.9) Retired 13 (19.1) 27 (60) Unemployed/ housewife 38 (55.9) 14 (31.1) Weight (kg) <60 36 (52.9) 9 (20) 61–70 14 (20.6) 12 (26.7) >70 18 (26.5) 24 (53.3) Data are presented as number (%). Table 2: Comparison of the severity of depression in patients with and without cataract surgery (n = 68). Mean Standard Deviation Degrees of freedom P-value Patients with cataract surgery 3.74 2.93 66 0.018 Patients without cataract surgery 5.60 5.12 0.284). In addition, there was a statistically significant difference between the mean depression score after cataract surgery in men (1.70) and women (4.94) (P < 0.001). However, based on the results of the present study, there was no statistically significant association between the mean depression score and age (P = 0.914). Visual function improved in all bilateral cataract patients who had surgery in one eye. Also, the results of this study showed that in all unilateral cataract patients who had eye surgery, visual function in the left and right eyes improved (Table 3). DOI 10.18502/sjms.v16i4.9942 Page 443 Sudan Journal of Medical Sciences Kiumars Nowroozpoor Dailami et al. Table 3: Visual acuity of unilateral and bilateral cataract patients after surgery. Visual Acuity Score Eye Glasses VA-CC VA-SC Manual-retinoscopy Auto-refractor OS OD OS OD OS OD OS OD Unilateral cataract patients 0.5– 0.7 2 (22.2) 2 (25) 3 (33.3) 3 (37.5) 2 (22.2) 1 (12.5) 1 (11.2) 0 (0) 0.8– 0.10 7 (77.7) 6 (75) 6 (66.6) 5 (62.5) 7 (77.7) 7 (87.5) 8 (88.8) 8 (100) Bilateral cataract patients 0.5– 0.7 7 (36.84) 8 (42.10) 10 (52.63) 9 (47.36) 6 (31.57) 6 (31.57) 4 (21.05) 5 (26.31) 0.8– 0.10 12 (63.15) 11 (57.89) 9 (47.36) 10 (52.63) 13 (68.62) 13 (68.62) 15 (78.94) 14 (73.68) Data are presented as number (%). OD: right eye; OS: left eye; VA-CC: visual acuity-with correction; VA-SC: visual acuity-without correction. 4. Discussion The results of the present study showed that cataract aggravates depression in elderly patients. However, cataract surgery in each eye can reduce the symptoms of depression. In addition, patients without cataract surgery suffer more from depression than normal people. Moreover, a statistically significant relationship was observed between patients’ gender and depression and cataract surgery. In addition, depression symptoms were significantly lower in men than in women who had cataract surgery. Visual function improved in all patients with bilateral cataract surgery. Cataract disease is associated with an increased risk of mental disorders, such as depression and psychological distress, it is usually associated with reduced quality of patient’s [24]. This finding is consistent with the results of studies from Vietnam [25, 26], Iran [18], Australia [10], and a joint study in Kenya, the Philippines, and Bangladesh [24]. On the other hand, contrary to the findings of the present study, the results of a study in the United States [21] showed that cataract surgery has no significant effect on reducing patients’ depression symptoms. Similarly, the results of an Australian study [27] also showed that cataract surgery increases vision-related quality of life, however, its effect on depressive symptoms was unknown. One possible explanation for this inconsistency may be the higher severity of depression in patients before surgery in the present study [25]. On the other hand, in the present study, the symptoms of depression in men were significantly lower than in women who had cataract surgery, which was inconsistent with previous studies in Canada [28, 29], the United States [30], and Vietnam [25]. It has been previously shown that the prevalence of depression in Iranian female patients is higher DOI 10.18502/sjms.v16i4.9942 Page 444 Sudan Journal of Medical Sciences Kiumars Nowroozpoor Dailami et al. than male patients [31, 32]. Therefore, higher severity of depression in women than men can be the reason for the lower severity of depression in women after cataract surgery [25]. It has been shown that bilateral cataract surgery is associated with improved visual function and cognitive function after surgery [18]. Therefore, the negative effect of visual impairment on cognitive status in these patients can be attributed to cataracts [33–36], and surgical intervention can improve patients’ visual and cognitive impairment [37, 38]. The results of Jefferis et al.’s study revealed that visual and cognitive function improved after bilateral cataract surgery [39]. Inconsistent with this finding, a study in the United States [40] showed an improvement of cognitive function and vision in older patients without cataract surgery. 5. Conclusion In conclusion, it seems that cataract can cause and exacerbates depression, and surgery can reduce the severity of depression in elderly patients. Moreover, in all patients who had unilateral cataract and were operated, increased vision was observed in both the right and left eyes. However, there is still insufficient evidence for cognitive improvement and reducing depression in patients after cataract surgery. Future studies are needed to validate our findings in different study population. Limitations This study has some limitations. Our study was observational and correlational in nature, and hence causality could not be established. There is a need for other well-designed cohort studies, preferably with longer duration of follow-up, to confirm the results of the present study. Additionally, only those patients who were referred to a teaching hospital in north of Iran were evaluated in this study, therefore, generalizability of the findings to other populations in different geographic regions is unclear. Acknowledgments None. DOI 10.18502/sjms.v16i4.9942 Page 445 Sudan Journal of Medical Sciences Kiumars Nowroozpoor Dailami et al. Ethical Considerations This study was approved by the university ethics committee. 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