Is there a link between the activity levels of parents and their children with cystic fibrosis? A scoping review

Introduction

Cystic fibrosis (CF) is a genetic condition affecting more than 10,500 people in the United Kingdom and is the most common lethal genetic disease in the Caucasian population (Sibley et al., 2006). People with CF have associated damage to the lungs which occurs from a build-up of viscous sputum. This indicates an importance in maximising the effectiveness of mucociliary clearance. There are various methods of airway clearance techniques (ACT) which are commonly used, including: exercise, manual techniques (such as percussions), breathing exercises, use of positive expiratory pressure (PEP) devices and the oscillatory versions of this (Cystic Fibrosis Trust, 2020).

There is evidence throughout the literature, including systematic and Cochrane reviews, that to maintain respiratory health, exercise and airway clearance are important (Flume et al., 2009; Patterson et al., 2019). Physical activity (PA) and exercise have shown a decrease in the number of pulmonary exacerbations and hospitalisations in the CF population, alongside improvements in cardiovascular endurance and quality of life in both children and adults (Rand & Prasad 2012; Patterson et al., 2019). The benefits of exercise have led to the question of whether exercise can be a replacement for ACT in people with CF, which would have implications for both research and clinical practice. Dwyer et al. (2019) found no significant difference in mucus clearance from the intermediate and peripheral lung regions when comparing treadmill exercise to PEP devices. When considering sputum clearance in central lung regions between PEP and exercise, however, there was a difference in expectoration indicating that exercise alongside traditional ACTs may be of greater benefit that ACTs alone. Although, this benefit may not be fully achieved due to issues with adherence.

Adherence is defined as the ‘extent to which the patient’s behaviour matches agreed recommendations from the prescriber’ (NICE, 2007, p. 2). Modi and Quittner (2006) reported adherence to overall treatment to be below 50% in children with CF. Goodfellow et al. (2015) also found adherence to be low in this population with 49% of patients being low-adherers to chest physiotherapy. Adherence to exercise and ACTs is important, as poor adherence to treatment has been linked to a decline in health outcomes, such as risk of hospitalisation for intravenous antibiotics and length of stay, which pose a significant burden on health outcomes and the National Health Service (NHS) in terms of costs (Eakin et al., 2011). Conclusions have been drawn that adherence to medication, exercise and chest physiotherapy in CF is an important research area and more is needed to better understand family barriers to adherence in order for clinicians to provide appropriate intervention (Goodfellow et al., 2015).

Research has shown a significant link between parental activity levels and that of their children in a healthy population. One study has showed that with an active mother, children were two times as likely to be active, with an active father they were three and-a-half times as likely to be active, and when both parents were active the child was almost six times as likely to be active (Moore et al., 1991). More recent studies, taking into account the change of environment in terms of technology and home/life balance have also found that children’s activity level depends on their parents’ levels of activity (Brzek et al., 2018). A pilot study from Emirza et al. (2018) showed that this significant difference in activity levels for parents and children extended into the population with CF. This pilot study concluded that parents should be included in PA training programme as part of clinic reviews, which would be a change in the way paediatric CF clinics are historically run. It should be noted that this study was carried out on a small sample size of 13 patients. PA tends to be lower in parents of children with chronic conditions, including that of CF. These decreased activity levels are amplified during the child’s inpatient stay (Vardar-Yagli et al., 2016).

Dempster et al. (2018) also showed how important parents are to a child’s adherence to treatment. Parent’s health beliefs were significantly related to children’s adherence to ACTs; higher importance placed on healthy lifestyles were associated with better adherence to treatment. Family-centred psychoeducational intervention has been a potentially promising supportive strategy for children with CF (Goldbeck & Babka, 2001). Possible mechanisms for the relationship between parents and children’s activity levels include the parents serving as role models, sharing of activities by family members, as well as enhancement and support by active parents of their child’s participation in PA (Moore et al., 1991). Family centred interventions on health beliefs can help to increase PA levels in children with CF (Hovell et al., 2009).

Exercise is a particularly important part of a child’s development in terms of cognition, general health and mental health (Biddle et al., 2019), as well as CF related health. Understanding the reasons for reductions in activity and the impacts these can have on patients is an important part of care for people with CF, to enable a practitioner to challenge and support in changing these behaviours.

To date this area has not been comprehensively reviewed. A scoping review has therefore been chosen to evaluate the current literature as it can be a particularly useful approach when the information on a topic has not been comprehensively reviewed or is complex and diverse (Munn et al., 2018). The aim of this scoping review is to synthesise evidence regarding how much parental activity can influence children’s activity levels and engagement in treatment amongst people with CF. The synthesis of evidence aims to explore this link as well as inform research, clinical practice and policy moving forwards.

Aims

The aims of the scoping review are to:

• Address whether there is a link between parent and child activity levels or adherence to treatment in CF.

• Understand whether family-based interventions exist to increase child adherence.

• Identify which outcomes measures have been used to determine any links.

• Identify areas of future research based on the current literature that is available within and around this topic.

Methods

Scoping reviews are a relatively new design of research and thus there are still inconsistencies with regards to its methodology. This scoping review methodology will be closely guided by the framework, following five steps, as proposed by Arksey and O’Malley (2005), and further developed by Levac et al. (2010).

Identify research question

The broad research question is to look at: How are the activity levels and engagement in physiotherapy of children with cystic fibrosis affected by their parents’ activity levels?

As discussed by Levac et al. (2010) there is a need in a scoping review to define the concept, target population, and health outcomes of interest. This definition allows for clarification on the focus of the scoping study. To facilitate this, a PICOT (Population, Intervention, Comparison, Outcome, Time) design was used, as described by Riva et al. (2012).

Table 1: PICOT used in study.

In order to establish an effective search strategy, the researchers aimed to consider the rationale for summarising this area of research.

Identify relevant studies

In consultation with a medical librarian, a search strategy was developed to identify relevant research to help answer the above question. This was carried out on 16th December 2020 (see Table 2 for search terms). In order to complete a comprehensive search of the existing literature Medline, Applied Social Sciences Index and Abstracts (ASSIA), Global Health and Web of Science search engines were used, to identify studies for this scoping review. This resulted in a total of 128 studies being identified (20 results on Medline, 93 results on ASSIA, 0 results on Global Health and 15 results on Medline); all duplicate studies between the search engines were removed prior to moving on to the study selection stage. The search strategy then progressed to searching reference lists of relevant studies for further appropriate research in which one additional paper was found through citations.

Table 2: Search terms.

Study selection

Inclusion and exclusion criteria were discussed between the authors prior to the study selection period, as suggested by Levac et al. (2010). The article titles and abstracts found from the database searches were screened by two authors independently applying the inclusion and exclusion criteria to all citations (KL and SC). Inclusion criteria were: studies including patients with CF; studies in English; a focus on parents and/or children; behavioural change. Exclusion criteria were: studies not in English; studies focusing on adults; studies with long term conditions other than CF.

A third author (DY) then reviewed the screened studies to establish any discrepancies between the 1st two authors. When any disagreements occurred, they were discussed under consultation with the third reviewer until an agreement on the final studies to include was reached. Ultimately, 8 studies were accepted in the study selection, alongside 1 abstract. At this stage, full copies of relevant studies were downloaded from journals or ordered through the Hospital library (Figure 1).

See Figure 1: Study selection.

Studies were not taken through to full analysis if there was no full paper. However, the abstract by Emirza et al. (2018) was particularly relevant based on the title Physical activity levels of children with cystic fibrosis and their parents: Pilot study and will therefore be discussed in brief during the review.

Charting the data

A data-charting form was developed looking at variables that could be extracted to answer the research question. The following variables were chosen:

1 Title of the study.

2 Authors of the study.

3 Working hypothesis.

4 Outcome measures used.

5 Sampling method used.

6 Description of participants (age, sex, cognition, inclusion/exclusion criteria).

7 Confounding factors (if identified).

8 Quality of paper using the Mixed Methods Appraisal Tool (MMAT).

9 Implications for further research.

10 Overall implications.

A critical appraisal skills programme (CASP) tool was used to facilitate the appraisal of research quality and the extraction of data from the eight full studies isolated from the search (Brice, 2018). The Mixed Methods Appraisal Tool (MMAT) is a critical appraisal tool for appraising during a systematic review of studies with mixed methods; it allows for appraising the methodological quality of both qualitative and quantitative data (Hong et al., 2018). The data variables used were chosen on review of previous scoping studies and altered over the process of the data extraction to allow researchers to become familiar with study data and model this into a meaningful format.

Collating, summarising and reporting the data

The full data collected is available in Appendix 1. The data collected was based on the variables chosen in the data charting section of the scoping review.

Results

Outcome measures

The identified studies included a mix of qualitative and quantitative methods, with quantitative studies generally looking for correlations between variables with no causal links discussed. The quantitative studies used a variety of designs, randomised control feasibility trial, pilot studies and cross-sectional studies. Forced expiratory volume in the 1st second (FEV1) was used as an outcome measure in two studies (Loutzenhiser & Clark 1993; Boucher et al., 1997) and PA questionnaires were used in three of the six quantitative studies (Loutzenhiser & Clark 1993; Hovell et al., 2009; Moola et al., 2017). Within the data set, a further quantitative questionnaire was used though it did not discuss PA, as well as a qualitative questionnaire.

There was no single outcome measure used to monitor PA. Whilst there was some evidence that physical activity monitoring devices appear to be an acceptable method for the objective assessment of PA (Shelley et al., 2018). Questionnaires were used most frequently, seen in three of the quantitative studies to review activity levels.

Population

There was no consensus on the age range throughout these studies. The minimum age was newly diagnosed children under one year of age, though this study focussed on parental knowledge (Goldbeck & Babka, 2001). Where children were engaged in questioning, six years old was the youngest age as seen in three of the studies. The maximum age appeared to vary dependent on the country in which the research was undertaken, though 19 was the eldest (Loutzenhiser & Clark, 1993); this appears to be in keeping with variations on strategies of transition from paediatric to adult care. Males and females were included in all of the selected studies. Inclusion and exclusion criteria also tended not to be discussed.

Confounding factors

Common confounding factors where discussed included: sample size and methodology, including sampling method. The majority of studies used convenience sampling. Two studies used randomised populations including that by Hovell et al. (2009), though in one case this was a randomised population from within one centre in a feasibility trial (Moola et al., 2017). In general, confounding factors were not discussed in these studies.

Critical evaluation of articles

The quality of studies again varied when using both the MMAT and CASP tools to examine them. The scores of the articles reviewed by the MMAT are stated in Table 3. The majority of studies have not stated how the findings support or will develop areas for future research.

Table 3: MMAT score.

Pilot study

The pilot study by Emirza et al. (2018) was particularly relevant to this study given its title. It was only presented as an abstract so limited information can be gained from it; however, its relevance warrants its review. The study used questionnaires to assess activity levels in both children and their parents. The total sample size was 13 patients and they concluded that there is a positive correlation between parental and children’s activity levels in CF at both moderate and vigorous intensities, though not at low intensity. They also felt that parents should be included in PA training programmes as when parents are actively involved in treatment, its effectiveness is improved. On discussion with the authors, this was a presentation and unfortunately, no further information on the method was available. This will be briefly discussed in the summary and report of data, though a formal MMAT and CASP were unable to be performed on this.

Discussion

There were very few studies produced during a literature search with an open question, showing the small amount of research in how parental behaviours and activity can affect the activity levels and engagement in physiotherapy treatment in children with CF. The evidence that is available varies in quality when using both the CASP and MMAT critical evaluation tools, this likely represents the infancy of this area of research. Whilst understanding how to better engage patients who have CF with their treatment has become a more focussed area of research in recent years, there is still clearly a lack of evidence base in this specific aspect.

There appears to be no definitive inclusion criteria to be used when researching the paediatric CF population. There is variability with regards to age range, though where there is questioning of children, which may be answered by the parents, six years of age appears to be the youngest. All articles include both female and males. Convenience sampling tended to be used throughout these studies with relatively low numbers of participants; this seems logical due to the relatively small numbers within local clinics but does affect the power of the studies. Individual centres tend to carry out their own research, which means that the majority of the research is specific to where this data was taken. A future approach may be to use multiple centres to improve the power and general acceptability of the studies.

Increasing the population size may also allow for confounding factors to be identified and discussed in more detail. The issues around the high number of confounding variables that come with convenience sampling, may be explained by convenience sampling as it is a non-randomised method of sampling that can lead to the under or over representation of specific groups inside the sample. The research methods used, alongside limitations with word counts may also contribute.

Understanding the complex psycho-social realities of living with a chronic illness is acknowledged across multiple studies. The psychological health of patients was seen to constrain PA and contribute towards reduced participation. Understanding this was important in developing educational and behavioural interventions to those with CF. Where this had been used to support and educate, it was reported to be a useful intervention. Though this does not discuss parental PA levels and its impact on children, the effective family behavioural interventions may be useful in this area if focussed on activity levels. Though there is limited value that can be taken from the pilot study by Emriza et al. (2018), as opposed to a fully powered randomised controlled trial, there is some evidence that exercise of parents has an association with the exercise levels of their children with CF.

Accelerometers are typically viewed as the gold standard in assessment of PA (Esliger & Tremblay, 2006), however, all of the studies that measured PA in this sample used questionnaires to measure this outcome. Questionnaires for measurement of activity levels have inconsistent results and often reporting errors, though are quicker, easier, and less expensive to use than accelerometers (Novak et al., 2020). The validity of this data is therefore in question, to improve this, accelerometers could be used in future studies. Whilst interventions and associations were reviewed in the studies measuring PA, parental activity levels were not one of these.

FEV1 was another outcome measure regularly used during these studies, though this is a better determinant of current health with no reports of long-term change in rates of decline in FEV1 in different exercise groups (Cheng et al., 2003). There is, however, an association when compared to a control, so FEV1 may be useful in the future as a supplementary outcome measure when reviewing parental and paediatric activity levels. There were no specific outcome measures with regards to physiotherapy used, such as adherence to physiotherapy questionnaires or the use of breath activated data logging nebulisers.

Individuals with CF engage in a variety of activities. CF was not perceived as a barrier to exercise per se, although participants acknowledged that they could be limited by their symptoms (Shelley et al., 2018). Experiences of PA among children and young people with CF, was seen as largely comparable to their non-CF peers; this gives more weight to the correlation between parental and a child’s activity levels seen by Moore et al. (1991) in the healthy population and its transition in people with CF. There is therefore more scope to investigate a link in activity levels of children with CF and their parents.

Study limitations

The variety of topics covered in selected studies make it challenging to select an appropriate outcome measure with which to review the evidence, collate and summarise it. The wide-range of study designs and methods used in the identified studies also made summarising data difficult. There were only eight full text studies found with which to review, this is a small body of work likely secondary to the lack of historical evidence and novelty of the area. A consultant stakeholder was not used as an optional additional stage of the study which could affect the ability of knowledge transfer and understanding of the evidence discovered.

Future research

A number of areas of research have been highlighted during this scoping review. Multiple studies noted a need for further development in PA assessment tools such as consumer level devices; they also recommended further research in validating paediatric specific PA tools. There are complex psycho-social realities in children with CF which act to constrain PA and contribute toward reduced participation; understanding these issues may allow for a better development of strategies to challenge non-adherence. Considering the initial question and lack of evidence around this, there is also a large scope for evidencing how parental activity levels are associated with a child’s activity levels and engagement in physiotherapy and more broadly CF treatment as a whole. With the emergency of CF modulator therapy and a discussion between professionals of using PA as a main ACT, understanding how therapists can impact a patient’s PA levels is particularly important.

Conclusion

In the literature at present there is no clear link between parental activity levels and child activity levels or adherence to treatment in those with CF. One pilot study, though in abstract form, is the beginnings of evidence to review this link. There appears to be a lack of evidence in the literature as to how activity levels are affected in children and young people with CF and the effect that the social aspect of the child’s life plays in this. During the review of the literature, family-based interventions have shown an ability to increase child adherence. The importance of understanding how to increase activity levels in these children is evident and there is a large potential for future research to be carried out in this area.

Funding

There was no funding for this scoping review.

Conflict of interest

The authors have no conflicts of interest to declare. All co-authors have seen and agree with the contents of the manuscript and there is no financial interest to report.

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