DISCUSSION
This study showed that the QoL is affected in varying degrees in the majority of healthy siblings of children with chronic disease. The QoL assessment of healthy siblings of 191 children with chronic disease at a median duration of 36 months following the diagnosis showed an impact on the psychosocial health, physical health, and total health scores of these siblings; these scores were significantly lower than those of the healthy siblings of healthy children. The impact was seen in both parents’ reports and healthy siblings’ self-reports. In several studies, psychosocial impact on the health sibling was observed in both the self-reports and parent reports (16,17); in contrast, there are other studies that reported no psychosocial outcomes in healthy siblings (18). Healthy siblings experience emotions such as withdrawal, aggression, depression, anxiety, guilt, and isolation, along with poor school performance and low self-esteem. As a result, they may feel lonely, ignored, excluded, neglected, and rejected (19,20,21,22,23,24). Although the majority of siblings of children with chronic disease have been negatively affected, most of these impacts are not considered psychopathological (10,25). However, whether the symptoms psychopathological or a way of coping with the situation, needs further investigation.
The factors associated with the psychosocial impact on the healthy siblings of children with chronic disease include the type and severity of the chronic disease, the time since diagnosis, and the healthy sibling’s age, gender, and coping skills (26). A severe and life-threatening disease has a larger impact on the psychological functioning of the healthy siblings, and their risk of having emotional and behavioral problems is 1.6-2 times greater than healthy children (27). The type and severity of chronic disease or disability of children may cause some effects that could be reflected in their respective siblings during adulthood (28,29). Based on the self-report of the healthy siblings, we found that the psychosocial health scores of the healthy siblings of the children with cerebral palsy, hematologic/oncologic disease, and asthma were significantly lower than that of the healthy siblings of healthy; the impact being most significant on the healthy siblings of children with cerebral palsy.
Healthy siblings of children with chronic disease may experience a loss of appetite, eating disorders, weight loss or overeating, and sleep disorders (21,22). However, the healthy children reported only a few physical symptoms when they became sick because of the severity of their sibling’s disease (21).
Combined chronic diseases are evaluated based on standard recommendations and by determining the impact of the diseases on family life rather than the specific effects and consequences of these diseases. In the present study, a comparison between the healthy siblings of children with chronic disease and those of healthy children showed that QoL scores were low; the impact was more obvious in some diseases, whereas in others, the scores were similar to those of the control group. This indicates that the diseases should be evaluated individually during QoL measurement. Studies have shown that in the presence of a sibling requiring a wheelchair, intensive care, or treatment at home/hospital (e.g., for cancer and cystic fibrosis) have a more significant negative impact on the QoL of the healthy sibling than healthy children (3,30). This may explain the negative impact on QoL of children with cancer and cerebral palsy groups. Since celiac disease only requires a diet change and no hospitalization or interventional therapies, its impact on the QoL of the healthy sibling is likely to be much lower than the healthy children. Although a previous study (3) on the healthy siblings of children with asthma have shown less impact on quality of life than the healthy children, our study showed that QoL was significantly affected in these children (3). This suggests that geographic differences may be important in QoL measurements; it also supports the hypothesis that the perception of disease may vary between different populations. Sharpe and Rossiter (25) showed that the psychosocial impact on healthy siblings of children with chronic disease with a high mortality risk (e.g., cancer) was similar to the impact on healthy siblings of children with chronic disease with a low mortality risk (e.g., diabetes, gastrointestinal diseases, and asthma). Thus, there is no clear consensus on the impact of the severity of the disease or poor prognosis on the QoL of the healthy siblings.
The time since diagnosis is likely to have an impact on the QoL of the healthy siblings as well as on the severity and prognosis of the chronic disease (19). We found that the psychosocial health, physical health, and total health scores of the healthy siblings of children with chronic disease were not associated with the duration of the chronic disease. Studies have shown that healthy siblings of children with cancer were most affected within the first month after the diagnosis, and the impact was reduced six months after the diagnosis (31). The increase in time since diagnosis led to a positive impact on the cancer patients’ siblings, but had no impact on the QoL of the healthy siblings of children with diseases such as epilepsy or diabetes (32). Some studies have shown that the impact on the healthy siblings of children with epilepsy and diabetes was reduced with an increase in age at diagnosis (33,34). Since it varies based on the type of disease, new studies are required to evaluate the impact of the duration after diagnosis on the QoL of the healthy siblings of children with chronic disease. Our evaluation based on the age groups of healthy siblings of children with chronic disease showed no difference in the parents’ report, whereas in self-report of the healthy siblings, the psychosocial health score was higher in the 13-17 and 7-12 age groups than in the 5-7 age group. The marked psychosocial impact observed in younger children indicates the importance of studies for support programs for children in this age group.
The QoL scores of healthy siblings of children with chronic disease were higher in the parents’ report than that in the healthy siblings’ self-report. This suggests that parents of children with chronic disease may overlook the impact of the chronic disease on the QoL of their healthy children. In contrast, in the parents’ report, the psychosocial health, physical health, and total health scores of the healthy siblings of children with chronic disease were significantly lower than those of the healthy siblings of healthy children. In the parents’ report, the psychosocial health scores of the healthy siblings of children with cerebral palsy, hematologic/oncologic diseases, asthma, diabetes, celiac disease, and epilepsy was significantly lower than that of the healthy siblings of healthy children; however, there was no difference in the psychosocial health scores between these conditions. In the presence of children with chronic disease, the psychosocial impact on the healthy children was perceived in a similar manner by the parents independent of the type and severity of the disease. The status of children or adolescents and their siblings has often been described through parents’ reports, which may overlook the changes in QoL of the healthy siblings, as shown in our study. Healthy siblings have usually been described by adults; however, there are substantial discrepancies between the perspectives of parents and their children. In a meta-analysis by Sharpe and Rossiter (25), the siblings’ self-reports were more positive than the parents reponse’s. Therefore, an evaluation of QoL of the healthy siblings would provide accurate information about their experiences and perceptions.
In most studies, the psychosocial assessment of healthy siblings is based on parents’ reports (18). Varni et al. (14,15) stated that a total health score <71.44 in child self-report scales and <67.44 in parent proxy-report scales indicated an “impaired QoL.” When assessing the impact on healthy children who grow up with a sibling affected by chronic disease, it is important to measure the relationship between the siblings from the healthy siblings’ perspective in addition to the QoL evaluations based on the adults’ perspective (35). In the self-report of the healthy siblings of children with chronic disease, 30.4% had an impaired QoL, which was higher than that of the healthy siblings of healthy children. In the parent reports, no QoL impairment was observed in the healthy siblings of children in the control group, but in 15.1% of the healthy siblings of children with chronic disease. The level of impaired QoL was lower in the parents’ report than that in the self-report of the healthy siblings, indicating that QoL impairment was noticed less by the parents.
Children with severe disease or disability had a more remarkable impact on the QoL of the healthy siblings than healthy siblings of healthy children. In the children’s self-reports, the prevalence of impaired QoL was 42.1%, 51.6%, 45.0%, and 30.7% in the cerebral palsy, hematologic/oncologic disease, asthma, and epilepsy groups, respectively—all higher than in the control group (14.1%). The prevalence of impaired QoL in healthy siblings of children with diabetes (9.9%) and celiac disease (3.3%) was lower than that of the healthy siblings of the children in the control group. Data on the healthy siblings of children with cancer are available; however, data on the healthy siblings of children with other chronic diseases are limited. Although there is no difference in bodily functions between the healthy siblings of cancer patients and their peers, they feel anxious about their health status (19). Murray et al. (23) reported that healthy children had a fear of developing the same disease as their siblings.
Our study has some limitations. This study aimed to evaluate the QoL of healthy siblings of children with chronic disease. However, we did not assess the disease severity for each type of disease, especially for children with cerebral palsy; this was due to the low number of children in each disease subgroup. While we enrolled children with epilepsy without neuromotor retardation, seizure frequencies might also affect the QoL of the parents and healthy siblings. Additionally, disease-related factors (especially celiac disease and diabetes) might affect the QoL; further studies are required to evaluate this.
Studies on the evaluation of QoL of the healthy siblings of children with chronic disease are limited. This is the first to include more than one type of disease and to assess the QoL from the perspective of both children and parents. Studies on healthy siblings of children with chronic disease are usually based on an evaluation of the QoL indexes of both the ill children and the healthy sibling; few studies have compared the healthy siblings of children with chronic disease and the healthy siblings of healthy children. Since different therapeutic approaches, the time since diagnosis, and the severity of disease/mortality may have a different impact on the QoL of the healthy siblings of children with chronic disease (26). Studies have shown that poor psychosocial functions observed in healthy siblings due to chronic disease or disability is also reflected during their adulthood (3,25,28,36,37). The relationship between the siblings is influenced by their cognitive, social, and emotional development, which are the determinants of QoL (38). Considering the frequency of chronic diseases and increased life expectancy, it is necessary to evaluate the impact of a child’s chronic disease on the child’s healthy siblings at home, mainly the psychosocial impact on their global QoL. The inclusion of healthy siblings in the support programs for parents of children with chronic disease may be beneficial (39,40), since brotherhood/sisterhood is a lifelong relationship that determines one’s identity and personality during adulthood.
The diagnosis of a physical chronic condition during childhood is a source of serious stress in the family and also has psychosocial impacts on the siblings of the children with chronic disease. The physical health, psychosocial health, and total health scores of healthy siblings of children with chronic disease were significantly lower than that of healthy siblings of healthy children. In healthy siblings, we observed a global impact on the HrQoL, including psychosocial scores, and a low level of parental awareness about this situation. This might increase the risk of emotional neglect and abuse of these children.
