Main findings of the study
Sleep disturbance is a highly common problem, with multiple contributing factors, and is experienced by family caregivers of children who transition from specialized pediatric facilities to their home.(2) Whereas short-term sporadic exposure to sleep deprivation over the course of a lifetime most likely will not have serious long-term consequences on neural functions, a relatively long and constant period of sleep deprivation, chronic sleep restriction or fragmentation can lead to serious acute and chronic damage to neural functioning.(10)
The mean global value obtained in the PSQI test for our sample was much higher than that obtained for a healthy normalized Portuguese population, where the mean global score was 1.20 (SD = 0.46), which shows a significantly impaired sleep quality.(11) However, this value is similar to the results of other populations of caregivers of patients with severe psychomotor development (mean global value of PSQI = 8, SD = 4) (12) and caregivers of adolescents with neuromuscular diseases under home mechanical ventilation (mean global value of PSQI = 7.4, SD = 4.7).(13)
Most of the sample (72.4%) obtained global scores greater than or equal to 5, which indicates the presence of difficulties in, at least, two components of the questionnaire, showing a higher risk for sleep disturbance.(11) On one hand, the literature associates sleep disruption with short-term health consequences (heightened stress response, pain, depression, anxiety and cognition, memory and performance deficits) and long-term health consequences for the caregivers (hypertension, cardiovascular disease, weight gain, metabolic syndrome and type 2 diabetes mellitus).(5) On the other hand, sleep disruption is associated with hampering the activities and duties of the caregiver, as well as the patient care.(14)
More than half of the caregivers (63.6%) perceived their own quality of sleep as good, despite the global value obtained in the PSQI test indicated a "good sleep quality" in only 27.3%. This may be because the caregiver gets accustomed to it.(13)
Caregivers of children/adolescents with respiratory disease were the ones that had the worst values in sleep quality (mean PSQI value = 11), followed by neuromuscular disease and central hypoventilation (mean PSQI value = 8). In previous studies, caregivers of children ventilated due to respiratory pathology presented mean PSQI values of 8.69,(14) caregivers of young people with neuromuscular diseases under home mechanical ventilation values of 7.4 (13) and mothers of children with congenital central hypoventilation syndrome values of 7.5.(15) There is an accentuated difference in the mean PSQI value in the respiratory group when compared to our study.
Caregivers of ACT group 2 presented the worst sleep quality (mean PSQI value = 9). Although no reports have been found in the literature that make this comparison between ACT groups, we can hypothesize an association to the longer trajectory of disease.
Regarding sleep duration, approximately half of the sample had an average sleep time superior to 7 hours, but 32.3% slept 6 hours or less per day. The basic need for sleep in a healthy adult is roughly 7.5 to 8.5 hours,(10) and less than 6 hours of sleep per night is not recommended, because deficits in cognitive functioning, especially memory, and response times have been found.(16)
Half of our sample had sleep efficiency indices below 85% (the normal value is 80%), which may be associated with drowsiness and diurnal dysfunction. A study has shown a significant difference in sleep efficiency between the caregivers of ventilated children and the caregivers of healthy children.(17)
A very significant percentage of caregivers reported sleep disturbance and/or daytime dysfunction, although this may not be directly related to the need for care provided to the child/adolescent. It was described that 52% of caregivers of ventilated children reported waking at least once a week to perform nighttime caregiving duties compared with 9% of caregivers of healthy children.(17) Furthermore, in families of technology-dependent children, a large proportion of families (22 out of 36) experienced regular sleep disruption, where parents reported getting up in the night at least twice a week.(18)
Approximately 25% of the caregivers need sleep medication, at least once a week, which is similar to what is recorded for a population of caregivers of ventilated children (24.1%).(17)
Sleep quality of the caregivers didn’t vary significantly with the attendance of a place of learning. In a study of children with respiratory disease, no differences in primary sleep outcomes were found between caregivers who completed questionnaires during the school year versus the summer/holidays.(14)
The type of interface and the number of daily hours using home mechanical ventilation didn’t seem to interfere with sleep quality. The duration of home mechanical ventilation and the time of the day when it was performed were identified as important factors for sleep disruption, with a greater negative impact with the increase in daily hours of home mechanical ventilation.(18) However, the longer-term use of non-invasive ventilation appears to result in an adjustment by the caregiver, with consequent improvement in sleep quality.(19)
Strength and limitations of the study
Within the limitations of the study, it is to highlight that the sample size is relatively small, making it difficult to find significant associations.
PSQI doesn’t provide detailed information on specific factors, which may vary depending on the underlying pathology and, therefore may influence the sleep quality of caregivers. The study was based on a subjective self-completion tool that can lead the caregiver to underestimate/overestimate the quality of the measured parameters. The fact that about 25% of the sample presented a sleep disorder may constitute a bias to the results found.
Sleep may be influenced by other variables not considered in this study (environmental issues, sleep hygiene habits, presence of one or more caregivers, child/adolescent’s disease stage).
It would be useful to carry out a prospective and longitudinal study, which would allow the questionnaires to be applied immediately before the onset of home mechanical ventilation and after a period of 3 to 6 months, in order to determine the impact of home mechanical ventilation on the sleep quality of the caregivers, reducing the interference of other external factors.
What this study adds
This study is one of the first in the international literature to specifically assess sleep quality of caregivers of children/adolescents with complex chronic disease under home mechanical ventilation. The sleep quality of the caregivers of children/adolescents under home mechanical ventilation is lower than that recorded in the healthy Portuguese population.
The authors concluded that the caregivers of children/adolescents with respiratory disease and of ACT group 2 had the worst values in sleep quality (mean PSQI value = 11 and 9, respectively). There is an accentuated difference in the mean PSQI value in the respiratory group of other studies when compared to our study. Besides, we haven’t found previous literature comparing sleep quality of caregivers of different ACT groups.
More than half of the caregivers perceived their own quality of sleep as good, despite the global value obtained in the PSQI test indicating a "good sleep quality" in less than one third.