Age-related macular degeneration (AMD) is a chronic, progressive disease and one of the most important reasons for irreversible visual impairment over 60 years old[15]. Older patients with impaired vision have more difficulties in daily activities for maintaining an independent lifestyle. With the advancing age, comorbidities, and loss of central vision by AMD, the quality of life diminishes. The relation between aging and depression is a well-known fact[16]. Depression becomes an inevitable problem when the effects of low vision are also added to these conditions.
Our study was a cross-sectional study. In this study, 37% of all AMD patients was female. This finding was not suitable with literature. In a study presented from America, %65 of the AMD patients was female[1]. The other conspicuous finding is that, in our study, the patients with dry AMD were 35,2% of all the patients. The patients with wet AMD are more commonly referred to our clinic for anti-VEGF injections and as a result they come to the clinic more commonly for applying of anti-VEGF treatment and control examination for possible complications of the injections. Hence, the ratio of patients with dry AMD was lower in our study.
In the present study, the lowest scores were obtained in the ‘Near activities’, ‘General health’, ‘General vision’ subscales, and the highest scores were obtained in the ‘Color vision’, ‘Ocular pain’, ‘Peripheral vision’ subscales. Schippert et al. published a report includes the association of demographic findings of Norwegian AMD patients and vision-related quality of life[17]. The highest score was obtained in ‘Ocular pain’ and the lowest score was obtained in ‘General vision’ and ‘Near activities’ in Norway population. In fact, the compatibility of our and this study can be based on pathophysiology of the age-related macular degeneration. AMD affects especially central vision, so peripheral vision can be protected at the acceptable levels and near vision can be effected also in the early stages of the disease[18].
The score of ‘General health’ subscale was 51,31 (± 18,91) in our study. In Schippert and co-workers’ study, the score of ‘General health’ was 47,28 (± 22,33). This condition can be explained with the differences in mean age of the participants between the two studies. Hence, the mean age of the patients was 72,94 in our study, and 81,7 in the other study. In the other subscales except ‘General health’, our NEI VFQ-25 scores were lower than the Norwegian population. The most remarkable difference was in the ‘Vision specific social functioning’ subscale of which scores were 66,07 (± 26,64), 83,33 (± 20,3), 85,5 (± 20,4) in our study, Norwegian and American population; sincerely[19]. We know that NEI VFQ-25 test had been prepared for the American population and culture. Life expectancy may differ between different countries and cultures.
Depression in advanced ages might be the initial sign of other diseases[20]. Therefore, early diagnosis of depression is important for geriatric practice. The diagnosis of depression is difficult, and affective symptoms are uncommon in elderly patients[21]. The short form of Geriatric Depression Scale includes 15 items (GDS-15), which is effective for the diagnosis of depression in elderly people and it is more brief, simple ,and time-effective than the original geriatric depression scale includes 30 items (GDS-30)[12]. Because of these advantages, we had used GDS-15 in the detection of depression. According to our study, the prevalence of depression was 62,96% in our patients. In a recently published study, Inan et al. presented the depression prevalence in the AMD group as 63,5%[22]. The previous studies have presented different ratios of depression in patients with AMD[23]. Mathew et al. found that, 44% of the patients with low vision associated with AMD have depression signs[23]. Durmaz et al. had applied the GDS-15 test to 329 patients who had admitted to the geriatric clinic for routine examination. In their study, depression ratio was 29,2%, but they had not considered any ocular or systemic disease, and the difference in the depression ratio between this and our study may be explained with low vision related to AMD. In addition to that, the female gender is one of the risk factors for the depression. According to several published studies, females are twice more depressive[24]. We found that the ratio of depression in females was significantly more than males (p < 0.05). In the patients with depression, the all scores of the subscales of the NEI VFQ-25 test were lower than the non-depressive group, and the only scores of ‘Ocular pain’, ‘Color and Peripheral vision’ subscales were not statistically significantly different between the two groups.
In the present study, 55% of the females had a worse visual acuity than 20/200 (Snellen test), and this ratio was only 20,5% in males. Although Rudnica et al. presented that, there was some evidence to suggest a higher risk of neovascular AMD and late AMD in women compared with men[25], the difference in the visual acuity between the genders was more remarkable in our study. The scores obtained from NEI VFQ-25 subscales except ‘Ocular pain’ and ‘Vision specific dependency’ were negatively correlated with aging (p < 0.05). Although, we have noticed that ‘Color-Peripheral vision’ and ‘Ocular pain’ subscales were the least affected parameters in AMD, with the effect of aging, color vision and peripheral vision scores decreased. Previous research has shown that the useful field of view seems to decline with aging[26] and Pinkers et al reported that, test error scores in the FM 100 Hue test had been increasing with aging[27].
Additionally, we evaluated the scores of NEI VFQ-25 subscales in anti-VEGF injected and non-injected patients separately. There were not any statistically significantly different scores in the subscales between the groups, and the visual acuity of the patients was not correlated with the number of the injections (p > 0.05). At the same time, the non-injected group was more depressive (p < 0.05). Senra et al. presented that, depression levels were significantly higher in patients who received up to 3 injections compared with patients who received from 4 to 12 injections and with patients who received more than 12 injections in the patients with wet AMD[28]. We hypothesised that, the anxiety levels against the anti-VEGF injections decrease as the number of intravitreal injections increase and they experience the rising in the visual acuity related to injections.
Lastly, we had not found any statistically significant differences in the NEI VFQ-25 subscales and GDS-15 test by the marital and income status of the patients (p > 0.05). Schippert et al, also showed that there is no relationship between marital status and vision-related quality of life subscales[17].
The limitations of this study include the small size of the sample that was used to investigate the outcome variables. We did not have a control group, with visual impairment associated with another ocular disease or with no visual impairment. On the other hand, the NEI VFQ-25 test had been prepared for the American population and culture.