By keeping track of the HRQoLin patients with wAMD receiving anti-VEGF treatment at baseline and follow-ups for one year, two significant findings were identified. First, the scores of NEI VFQ-25overall scale and subscales were fluctuated before and after the wAMD patients receiving the treatment, with the highest scores at the 6 months follow-up and lowest scores at the baseline. Second, the variables that predict QoL varied across time, with BCVA and depression remaining as predictors across the five time points.
In our study, the total score and the subscales related to vision (eg. ‘general vision’, ‘general health’, ‘near activities’, ‘distance activities’, ‘color vision’ and ‘peripheral vision’) of NEI VFQ-25 had improved by following the course after receiving the treatment and reached the peak at 6 months follow-up.This may imply that the continuous improvement of the vision and wAMD patients’ daily living abilities at the first 6 months, their HRQoL had also improved across the time. However, the total score of HRQoL was on average the same as at baseline, this finding was same with Finger’s research. Low number of injections and irregular follow-ups caused unstable improvement of vision, high expectation and disappointment on the treatment outcomes may lead the improvement of HRQoL could not be maintained at 12 months follow-up. Furthermore, because of fewer professional vision rehabilitation institutions and incomplete service network, the needs of patients for visual rehabilitation could not be met in China at present. Just as the developed country did, it is impossible to provide more comprehensive information support, supervision of regular follow-ups and professional visual function training for the discharged patients like it did in developed country. On the meanwhile, the social functioning subscale was following the variation trend of subscales related to vision. The patients were more willing and confident to communicate with others and participate into the social activities after the vision have been improved. Otherwise, they preferred to staying at home and keeping them isolated from the outside. We can also find that the scores of the driving subscale was constantly declined from the baseline to follow-ups. This result may be explained by the fact that driving requires high level of vision, so most of the wAMD patients gave up driving regardless of whether the vision was improved or not after treatment. One interesting finding is that the scores of the subscales of role difficulties and dependencywere the lowest at 3 and 6 months follow-ups although the vision had significantly improved. A possible explanation for this might be that most of the wAMD were elderly people, and in Chinese traditions, they were taken care by their spouses or children instead of professional institutes. The relatives played an important role in their vision rehabilitation. They can help the patients with daily activities, giving the comfort, and taking them to return visits which were the most frequent in the first six months, so the patients showed more dependency on their families. On the other hand, increase of dependence would reduce the initiative and authority of the elderly at home, causing a strong sense of loss, which could lead to the difficulty of role adjustment.
The subsequent step aimed to figure out the variables that predict HRQoL at different time points. With the total score of NEI VFQ-25 as the dependent variable, the regression analysis was carried out with 17 variables including demographic data, medical condition and social psychological index as the independent variables. The results showed that the HRQoL in wAMD patients was influenced by many factors, which were also changed along with the process of treatment.
Demographics like ‘gender’, ‘area of residence’, ‘education’ and ‘income’ were identified to significantly influence the HRQoL. Male patients with high level of income and education, and livingin urban areasshowed better HRQoL. At the early and middle stages of treatment, the economic burden was one of the important factors that affect the quality of life. Due to Chinese health care system, the wAMD patients have to afford expensive anti-VEGF drugs at their own expense, which becomesa burden to the family. Therefore, the lower the income means heavier the economic burden, the poorer the quality of life. However, in the later stage of treatment, with the decrease in frequency of treatment, the patient's financial burden is reduced, the economic burden is no longer the main factor affecting the quality of life of patients at the 12 months follow-up. Also, area of residence and education played an important role in predicting HRQoL at 3months follow-up. At the first three months of treatment,lack of knowledge of disease was an important factor affecting the quality of life, and patients with higher educational level were more inclined to effectively seek information support. With the process of treatment, patients with lower educational level got more and more information about the disease, and the impact of education on the quality of life of patients weakened. On the other hand, gender was found to influence the HRQoL at the 3 months and 6 months follow-up. The total score of NEI VFQ-25 of female patients were lower than those of male patients. The reason for this may be the personality characteristics of the female patients are vulnerable and sensitive, and the negative emotions such as nervousness, depression and inferiority are more likely to occur than the male patients which resulting in poorer quality of life.
In addition to demographic variables, we also found the clinical characteristics like ‘BCVA’ and ‘VA treated eye’ were significantly factors in predicting the HRQoL. The improvement in BCVA were associated with improvement in HRQoL had been proved in many studies[33, 34]. The possible explanation was patients relied on BCVA with daily activities through the whole process of treatment, and could get better use of residual vision with the rehabilitation training. Therefore, BCVA became the key impact factor to be the predictor across the five time points. On the other hand, patients paid much attention to the VA treated eye at the early and middle stage of treatment, then they adapt to the changes of visual function, and the visual acuity of treated eye was no longer an important factor of HRQoL at 12 month follow-up. Also, impact factor ‘eye affected by AMD’ was also found to influence the HRQoL at 12 month follow-up. NEI VFQ-25 Scores of bilateral patients were lower than those of unilateral patients . This may be patients are mainly concerned about 'BCVA' and 'VA treated eye' in the early stage. However, with the vision is stable or decreased, the unilateral patients can still depend on the visual acuity of the other unaffected eye, while the bilateral patients are unable to adapt to their losing visual function in the later stage.
Consistent with other studies, we found higher depression and anxiety were significantly associated with poorer HRQoL[12, 37], and the depression was found to be the predictor of HRQoL across all the time points. The prevalence of depression in AMD was reported between 17.9% and 43%. Symptoms of AMD, including difficulty in daily activities, recognising others and joining into the housework, may directly lead to social isolation, depend on others, and role conflicts which would in turn result in an increase in depression and anxiety. Also, because of the uncertainty of AMD treatment, they are constantly worried about whether the positive effects of treatment could be able to sustain or eventually leading to inevitable blindness though the whole treatment time . Furthermore, the great economic burden would aggravate the symptoms of depression and anxiety especially in the middle stage of treatment. However, some patients tried to make the coordination of daily life difficulties and emotional conflict, develop positive coping strategies, and take a positive optimistic attitude towards life during the longer duration of AMD. Therefore, the symptom of anxiety and depression eased in later stage.
Social support was also found to be significantly related to HRQoL at 3 months, 6 months and 12 months follow-ups. Social support was confirmed to help the patients to promote good mental state and face diseases caused by a variety of physical function, psychological and social difficulties, so as to improve the patients' compliance and quality of life. For Chinese culture, the family was the main source of the social support during the long-term treatment and rehabilitation. They involved into the vision rehabilitation services which had a vital impact on the health outcomes of patients. Furthermore, the support as information, how to manage the symptoms and improve the ability of psychological adjustment and management strategy supplied by the medical staff was an important role in promoting the improvement of survival quality.
We also assessed the effect of self-efficacy and found it has a positive effect on quality of life at 1, 3 and 6 months follow-ups.Self-efficacy refers to that to what degree does a person think of his actions that would lead to a certain outcome, which means the expectation that an individual would successfully perform a behavior. With the progress of treatment, patients with high level of self-efficacy regarded conflicts and difficulties as a chance to improve abilities and had great confidence in the success of the treatment. They imagined the success scenario and adopt positive health behaviors to promote effective cognitive reconstruction process. Conversely, a healthy and effective cognitive and behavioral experience could strengthen self-efficacy and beliefs, so the patients would show more active adaptability and strive to overcome the various symptoms caused by daily life, social and psychological barriers throughout the treatment and nursing process which could improve the HRQoL of the AMD.
Other psychosocial variables such as negative and positive coping were demonstrated to be the significant determinant of HRQoL at 6 months follow-up which was partly consistent with Sturrock’s findings. In their study, only avoidant coping not acceptance coping was observed to significantly determined decline in vision-related functioning. This may be because of inadequate professional vision rehabilitation organization to help the patients to develop positive coping ability in China. They had to form the special coping strategies gradually when dealing with the disease. Therefore positive or negative coping style will affect patients' subjective understanding, problem-solving ability and mental health. Also, different scales used to test the coping ability may lead the different outcomes.
As is the case with all studies, some limitations must be noted. Firstly, a relatively small and single sample size was recruited in our study, and the findings may not be generalized to all the AMD patients in China. Secondly, due to time constraints and dropout of the patients, we only did the 12 months follow-up. Advanced computer-based HRQOL instrument like eye-term bank should be adopted in the future studies to evaluate the predictors of HRQOL changes. Finally, although we have tried our best to include all the impact factors which we assumed to be the predictors of HRQoL in AMD patients, some other potential predictors may be missed which might be significantly related to HRQoL. Nevertheless, this study is the focus on HRQoL and predictors of disease trajectory in five time points, which could understand its dynamic changes more precisely and provide more accurate information for the clinical working. Also, not only the sociodemographics and clinical characteristics, but also the psychosocial indicators that influence HRQoL were brought into our predicting analysis which had been neglected or incomplete by other studies.