Chapter 2: Literature review
2.4 Delivery of lifestyle interventions for weight loss
Current obesity guidelines recommend that individuals participate in a comprehensive lifestyle intervention for at least 6 months to attain meaningful weight loss (≥5%) [Wadden et al., 2020; Jensen et al., 2014]. It is also strongly recommended that 14 in-person individual or group sessions are attended in this 6-month period [Raynor & Champagne, 2016; Jensen et al., 2014] as high intensity interventions have been associated with meaningful weight loss, as reported by Perri et al. (2014).
Such programs should be delivered by trained individuals, such as dietitians, psychologists, health workers or trained laypersons, who use behavioural therapy to change dietary intake and physical activity behaviour [Jensen et al., 2014]. When compared to individual sessions, group sessions are favoured as it has shown to be more cost effective and yield similar weight loss results [Renjlian et al., 2001]. Wadden et al. (2020) also state that web-based interventions and evidenced-based commercial programs can be considered if it is comprehensive and similarly structured as the in- person sessions.
Several systematic reviews have reported that it is the intensity of an intervention (i.e. the frequency of sessions) rather than the mode of delivery, that is strongly associated with weight loss [Jensen et al., 2014; Wadden et al., 2014; LeBlanc et al., 2011]. However, intensive lifestyle interventions require healthcare providers who have been well-trained and have the time to deliver such interventions, while for the participants, this can also be costly and time-consuming and requires access to healthcare [Wadden et al., 2020]. Within the South African setting, there are huge wealth inequalities
30 where the bottom 70% of the population earn a meagre 17% of the total annual national income. In addition, South Africa bears a heavy burden of infectious disease with one of the worst tuberculosis infection rates in the world (737 per 100 000), as well as carrying 17% of the global burden of HIV infection. In the private sector, 70% of the country’s doctors serve 17% of the population who have private health insurance, while 83% of the population are served by the public sector where only 30%
of the doctors are employed. [Benatar & Gill, 2021]. Access to healthcare and healthcare providers in overburdened health facilities is therefore a challenge and the capacity to take on additional responsibilities and duties, such as conducting intensive lifestyle interventions, is limited. Considering various delivery options to ensure the delivery of sustainable and effective lifestyle interventions are therefore important.
2.4.2 Workplace interventions
In recent years, investigation of health programme delivery in the workplace has become a focus in research studies, mainly in high income countries, as it has been shown to be associated with improved employee health [Eng et al., 2016; Goetzel et al., 2014; Loeppke et al., 2008]; improved productivity [Eng et al., 2016; Gates et al., 2008], reduced medical costs [Goetzel et al., 2014; Hochart
& Lang, 2011], reduced disease prevalence [Jung et al., 2012; Boshtam et al., 2010] and even more joyful and loyal employees [Fitzgerald & Danner, 2012].
Schneider et al. (2009) maintain that both wealthy and poor South Africans are affected by obesity and NCDs and that interventions aimed at treatment and prevention must be cost-effective, well- planned and feasible across all levels of society. Pratt et al. (2007) suggest that workplace interventions could reach a significant number of working adults from a range of socio-economic and cultural backgrounds. WHO and others have recommended that institutions improve their employee health and wellbeing by approving and enforcing health promotion and NCD prevention programmes in the workplace [Cahill et al., 2014; WHO, 2010].
Workplace interventions have shown positive results regarding psychosocial and behavioural effects on lifestyle factors such as physical activity, smoking and dietary behaviours [Cahill et al, 2014; WHO, 2009]. A 2014 systematic review investigated the effectiveness of workplace interventions which focused on diet and/or physical activity and found that 11 out of the 15 included studies showed small but significant changes in physical activity, fitness, dietary behaviour or weight [Schroer et al., 2014].
Similar findings were observed in an earlier systematic review which consisted of 9 studies [Verweij et al., 2011]. The workplace is considered an ideal site for lifestyle interventions as the number of employees remain constant over the period of the intervention and messengers and regular health check-ups can be included in the design of the intervention [Kim et al., 2015]. Additional benefits associated with workplace interventions include increased productivity, a decrease in absenteeism
31 and medical costs. The approach of implementing weight loss interventions at the workplace is considered highly effective [Jensen et al., 2014; Wang et al., 2011; Kumanyika et al., 2008].
Wadden et al. (2020) suggest that a community setting, such as a workplace, could be used to deliver a high intensity, comprehensive lifestyle intervention where group sessions could be used instead of individual sessions to reduce costs. High-intensity, community-based interventions have effectively been conducted by trained laypersons or community weight loss specialists [West et al., 2018].
2.4.3 Telephonic delivery
As previously mentioned, a systematic review found that high intensity lifestyle interventions yield meaningful weight loss (6%), whether the delivery mode is in-person or via the telephone [LeBlanc et al., 2011]. Schmittdiel et al. (2017) suggest that interventions delivered telephonically may be able to promote weight loss at a population level. Such interventions are often efficiently conducted by non- physician healthcare providers who provide support, information and skills to promote behaviour change and self-efficacy [Sangster et al., 2015; Tao et al., 2014; Hersey et al., 2012; Terry et al., 2011]. The telephonic mode of delivery can therefore be considered cost-effective with an extensive reach. These sentiments are also shared by Wadden et al. (2020) who describe interventions delivered via telephone as having many benefits such as increased reach to individuals in rural areas, greater convenience and being less expensive. Despite all the potential benefits a telephonic intervention may hold, it is not a widely adopted mode of delivery in weight loss interventions [Schmittdiel et al., 2017].
2.4.4 Self-help delivery
As mentioned above, high frequency, in-person interventions have been proven to be effective in promoting weight loss, but such interventions require specialist health worker inputs and resources, making it expensive. Self-directed interventions or self-help interventions may provide a low-cost delivery option as limited or no professional contact is required and its format may include print, the internet or mobile-delivered interventions [Hartmann-Boyce et al., 2015; Tang et al., 2014].
A systematic review by Tang et al. (2014) on individual-level self-help interventions included 20 reviews. Inclusion criteria were normal weight, overweight or obese adults as a target group, a focus on physical activity and or dietary behaviours and included at least one weight-related outcome such as weight or BMI. Results showed that the modes of delivery of the self-help interventions included the internet, mobile electronic devices, print media and a combination of these. The findings further suggest that self-help weight loss interventions can independently promote weight loss and can also enhance interventions that include a personal contact component [Tang et al., 2014]. BCTs such as self-monitoring, feedback, self-efficacy, enhancement and social and peer support were used in
32 successful self-help interventions that were reviewed. No conclusions could, however, be drawn by Tang et al. (2014) regarding the most effective BCTs or mode of delivery most strongly associated with weight loss.
In 2015, a similar review was conducted by Hartmann-Boyce et al. (2015), who reviewed randomised controlled trails of self-help interventions, focusing on the content of the interventions rather than the mode of delivery. The primary outcome of the investigation was mean difference in weight change between the study arms at six months after baseline. Twenty-three studies were included; 12 compared self-help interventions with minimal interventions (no additional contact with or without printed information on consequences of obesity), seven compared personalised or interactive programs with fixed interventions (non-tailored, non-interactive), and two compared tailored and interactive interventions with non-personalised, interactive interventions. The modes of delivery applied in the trials included print media, internet, mobile electronic devices that included self- monitoring devices such as pedometers. Self-monitoring and goal setting was the most commonly incorporated BCT amongst the included studies [Hartmann-Boyce et al., 2015].
Of interest is that most of the 23 studies included in this review preferentially included participants that were considered more advantaged by way of the formulated inclusion criteria [Hartmann-Boyce et al., 2015]. This is not surprising, as interventions with a digital component may require expensive equipment such as computers and smartphones as well as data and electricity. Moreover, only one study in the review investigated the association between socio-economic status and intervention outcomes and found that it was more effective in participants with a higher socio-economic status [Beeken et al., 2012]. Bearing in mind the huge wealth disparities in South Africa, self-help interventions that include tailoring and automated interactivity may not be effective for the large majority of the population. Whether minimal self-help options would be suitable for and effective in lower socio-economic groups is questionable. Results of the review suggest that these groups may require more support than what is provided by self-help interventions alone [Hartmann-Boyce et al., 2015].
2.4.5 Digital delivery
Interventions that utilise technology, often referred to as eHealth (electronic health) or mHealth (mobile health), have decreased the need for expensive in-person contact from a specialised healthcare provider. This delivery methods may therefore decrease the costs of interventions and have a much greater reach making it affordable and convenient [Raynor & Champagne, 2016]. Most eHealth interventions include features which assist with self-monitoring and goal setting and provide feedback on diet, physical activity and weight [Wadden et al., 2020]. Some form of personalised feedback has been identified as a critical component of effective eHealth interventions [Schippers et al., 2017; Jensen et al., 2014]. Many programmes use algorithms that generate automated,
33 personalised feedback based on analysis of self-monitoring data [Tate et al., 2006]. Although such platforms are generally costly, Joseph et al. (2018), in their health awareness intervention for overweight and obese educators found an inexpensive service provider which provides outreach to developing countries such as South Africa, making it a cost-effective option.
The first eHealth interventions were computer-based and included an intervention website (education material, tracking system, discussion board, chat room or email) or a predominantly email-based format where providers interacted with participants via email [Raynor & Champagne 2016]. Although computer-based interventions result in greater weight loss than minimal interventions lasting six months, face-to-face interventions result in greater weight loss than interventions delivered by the internet or email [Jensen et al., 2014; Wieland et al., 2012].
Mobile phone ownership has significantly increased globally and in South Africa, over the last few decades and more recently also ownership and use of smartphones. [ICASA, 2020]. According to the Independent Communications Authority of South Africa (ICASA)’s 2020 report, there were 78 million mobile cellular data subscriptions and more than 53 million smartphone subscriptions nationally [ICASA, 2020]. Stats SA’s latest General Household Survey data also revealed that 60% of South African households had internet access using a mobile device in 2018 [Stats SA, 2018].
mHealth incorporating mobile devices and applications (apps) have become increasingly popular with more than 300 000 health apps available, of which nearly 30 000 reported to be weight loss apps [Jimenez et al., 2019; Nikolaou & Lean, 2017; Nichols, 2017], which were not typically developed with the guidance of healthcare professionals (only 0.05%) [Nichols, 2017]. However, there is consensus that smartphone apps can be used to administer weight loss interventions that are cost-effective, evidence-based and personalised [Siriwoen et al., 2018; Toro-Ramos et al., 2017]. In a recent systematic review consisting of 12 studies, smartphone app features such as self-monitoring, personalised goal-setting, feedback, as well as reward system, counselling and social support were found to increase self-regulation, which can promote healthy behaviours and subsequent weight loss [Wang et al., 2020]. Factors that could impact negatively on the effectiveness of smartphone apps include poor digital competence, data privacy concerns and restricted availability of technology [Fleming et al., 2020; Blenner et al., 2016].
Short message service (SMS) or text messaging is a messaging service on mobile phone devices and has been utilised in health and weight loss intervention delivery [Hall et al., 2015]. Messages can include up to 160 characters. Using text messages in intervention is not complex, cost-effective and can serve as a cue to action, making it a popular approach for eHealth interventions [Schippers et al., 2017; Atun & Sittampalam, 2006; Goggin, 2006; Ling, 2004; Rice & Katz, 2003]. Mobile phone usage has been found to be high in overweight population groups and those with a lower socio-demographic
34 status, making it an ideal delivery mode for weight loss interventions for these groups [Koivusilta et al., 2007; Lajunen et al., 2007; Koivusilta et al., 2005].
Seven out of 14 studies included in a 2012 systematic review reported on the feasibility and acceptability of text messaging as a delivery mode for weight loss interventions. All seven found that text messaging seemed to be feasible and acceptable and demonstrated a significant effect on weight loss, diet or exercise [Shaw & Bosworth, 2012]. Results from a 2014 systematic review support these findings, with participants in weight loss interventions that included a text messaging component, losing on average seven times more weight than participants who did not receive text messaging [Siopis et al., 2015]. Both reviews concluded that there were inconsistencies in timing and frequency of delivery of text messaging across reviewed studies and recommended that further research in this regard was needed [Siopis et al., 2015; Shaw & Bosworth, 2012]. However, Shaw and Bosworth (2012) concluded that at least one text message every day was necessary to motivate participants to engage in weight loss behaviours without it becoming a burden.
The effect of weight loss interventions delivered via mobile phones was also the focus of a 2017 meta- analysis consisting of 12 randomised controlled trials (RCTs) [Schippers et al., 2017]. Although this study demonstrated that trials resulted in significant weight loss, the greatest effect size was observed for weight loss interventions that combined mobile phone delivery with other delivery modes such as email, face-to-face contact or phone calls, to enable personal contact and frequent interactions.
Schippers et al. (2017) recommend that further research is required to determine the best additional delivery modes and BCTs to combine with mobile phone delivery to create a greater sense of personal contact for example a personalised text or voice message.