Clarifications on the intersectional MAIHDA approach: A conceptual guide and response to Wilkes and Karimi (2024).

Intersectional Multilevel Analysis of Individual Heterogeneity and Discriminatory Accuracy (MAIHDA) has been welcomed as a new gold standard for quantitative evaluation of intersectional inequalities, and it is being rapidly adopted across the health and social sciences. In their commentary "What does the MAIHDA method explain?", Wilkes and Karimi (2024) raise methodological concerns with this approach, leading them to advocate for the continued use of conventional single-level linear regression models with fixed-effects interaction parameters for quantitative intersectional analysis. In this response, we systematically address these concerns, and ultimately find them to be unfounded, arising from a series of subtle but important misunderstandings of the MAIHDA approach and literature. Since readers new to MAIHDA may share confusion on these points, we take this opportunity to provide clarifications. Our response is organized around four important clarifications: (1) At what level are the additive main effect variables defined in intersectional MAIHDA models? (2) Do MAIHDA models have problems with collinearity? (3) Why does the Variance Partitioning Coefficient (VPC) tend to be small, and the Proportional Change in Variance (PCV) tend to be large in MAIHDA? and (4) What are the goals of MAIHDA analysis?

Use of Intersectionality Theory in Interventional Health Research in High-Income Countries: A Scoping Review.

BACKGROUND: Intersectionality theory posits that considering a single axis of inequality is limited and that considering (dis)advantage on multiple axes simultaneously is needed. The extent to which intersectionality has been used within interventional health research has not been systematically examined. This scoping review aimed to map out the use of intersectionality. It explores the use of intersectionality when designing and implementing public health interventions, or when analysing the impact of these interventions. METHODS: We undertook systematic searches of Medline and Scopus from inception through June 2021, with key search terms including "intersectionality", "interventions" and "public health". References were screened and those using intersectionality and primary data from high-income countries were included and relevant data synthesised. RESULTS: After screening 2108 studies, we included 12 studies. Six studies were qualitative and focused on alcohol and substance abuse (two studies), mental health (two studies), general health promotion (one study) and housing interventions (one study). The three quantitative studies examined mental health (two studies) and smoking cessation (one study), while the three mixed-method studies examined mental health (two studies) and sexual exploitation (one study). Intersectionality was used primarily to analyse intervention effects (eight studies), but also for intervention design (three studies), and one study used it for both design and analysis. Ethnicity and gender were the most commonly included axes of inequality (11 studies), followed by socio-economic position (10 studies). Four studies included consideration of LGBTQ+ and only one considered physical disability. Intersectional frameworks were used by studies to formulate specific questions and assess differences in outcomes by intersectional markers of identity. Analytical studies also recommended intersectionality approaches to improve future treatments and to structure interventions to focus on power and structural dynamics. CONCLUSIONS: Intersectionality theory is not yet commonly used in interventional health research, in either design or analysis. Conditions such as mental health have more studies using intersectionality, while studies considering LGBTQ+ and physical disability as axes of inequality are particularly sparse. The lack of studies in our review suggests that theoretical and methodological advancements need to be made in order to increase engagement with intersectionality in interventional health.

Neighbourhood deprivation and intersectional inequalities in biomarkers of healthy ageing in England.

While social and spatial determinants of biomarkers have been reported, no previous study has examined both together within an intersectional perspective. We present a novel extension of quantitative intersectional analyses using cross-classified multilevel models to explore how intersectional positions and neighbourhood deprivation are associated with biomarkers, using baseline UK Biobank data (collected from 2006 to 2010). Our results suggest intersectional inequalities in biomarkers of healthy ageing are mostly established by age 40-49, but different intersections show different relationships with deprivation. Our study suggests that certain biosocial pathways are more strongly implicated in how neighbourhoods and intersectional positions affect healthy ageing than others.

Can intersectionality help with understanding and tackling health inequalities? Perspectives of professional stakeholders.

BACKGROUND: The concept of "intersectionality" is increasingly employed within public health arenas, particularly in North America, and is often heralded as offering great potential to advance health inequalities research and action. Given persistently poor progress towards tackling health inequalities, and recent calls to reframe this agenda in the United Kingdom and Europe, the possible contribution of intersectionality deserves attention. Yet, no existing research has examined professional stakeholder understandings and perspectives on applying intersectionality to this field. METHODS: In this paper we seek to address that gap, drawing upon a consultation survey and face-to-face workshop (n = 23) undertaken in the United Kingdom. The survey included both researchers (n = 53) and policy and practice professionals (n = 20) with varied roles and levels of engagement in research and evaluation. Topics included familiarity with the term and concept "intersectionality", relevance to health inequalities work, and issues shaping its uptake. Respondents were also asked to comment on two specific policy suggestions: intersectionally targeting and tailoring interventions, and evaluating the intersectional effects of policies. The workshop aims were to share examples of applying intersectionality within health inequalities research and practice; understand the views of research and practice colleagues on potential contributions and challenges; and identify potential ways to promote intersectional approaches. RESULTS: Findings indicated a generally positive response to the concept and a cautiously optimistic assessment that intersectional approaches could be valuable. However, opinions were mixed and various challenges were raised, especially around whether intersectionality research is necessarily critical and transformative and, accordingly, how it should be operationalized methodologically. Nonetheless, there was general agreement that intersectionality is concerned with diverse inequalities and the systems of power that shape them. CONCLUSIONS: We position intersectionality within the wider context of health inequalities policy and practice, suggesting potential ways forward for the approach in the context of the United Kingdom. The views of policy and practice professionals suggest that intersectionality has far to travel to help counter individualistic narratives and to encourage an approach that is sensitive to subgroup inequalities and the processes that generate them. Examples of promising practice, albeit mostly in North America, suggest that it is possible for intersectionality to gain traction.

Learning from the experience of peer support facilitators and study nurses in diabetes peer support: A qualitative study.

OBJECTIVES: We report on the experiences of peer support facilitators and study nurses who participated in a large trial of peer support for type 2 diabetes. The support was led by volunteer peer support facilitators, who were trained in overcoming barriers to diabetes care, motivational interviewing, listening skills and setting up and running group support sessions. There is currently a distinct lack of qualitative evidence on what works in peer support. METHODS: The peer support facilitators and study nurses completed open-answer questionnaire items on what worked well and less well, problems encountered and how they were resolved, group dynamics and suggestions for improvement. We also collected data from end-of-study meetings. Inductive thematic analysis was used to allow the emergent themes to be strongly based in the data.Findings: We find that process factors, peer support facilitator and peer characteristics, their relationships with each other and group dynamics are all fundamental for effective peer support. Sustaining and ending support also emerged as a key theme. DISCUSSION: Given the increasing interest in peer support, these findings will be useful to those interested in running groups in the future. Training programmes should help peer support facilitators develop confidence whilst emphasising that peer support ideally entails an equal, democratic dynamic. More attention is needed on to how to end groups appropriately.

Understanding unequal ageing: towards a synthesis of intersectionality and life course analyses.

Intersectionality has received an increasing amount of attention in health inequalities research in recent years. It suggests that treating social characteristics separately-mainly age, gender, ethnicity, and socio-economic position-does not match the reality that people simultaneously embody multiple characteristics and are therefore potentially subject to multiple forms of discrimination. Yet the intersectionality literature has paid very little attention to the nature of ageing or the life course, and gerontology has rarely incorporated insights from intersectionality. In this paper, we aim to illustrate how intersectionality might be synthesised with a life course perspective to deliver novel insights into unequal ageing, especially with respect to health. First we provide an overview of how intersectionality can be used in research on inequality, focusing on intersectional subgroups, discrimination, categorisation, and individual heterogeneity. We cover two key approaches-the use of interaction terms in conventional models and multilevel models which are particularly focussed on granular subgroup differences. In advancing a conceptual dialogue with the life course perspective, we discuss the concepts of roles, life stages, transitions, age/cohort, cumulative disadvantage/advantage, and trajectories. We conclude that the synergies between intersectionality and the life course hold exciting opportunities to bring new insights to unequal ageing and its attendant health inequalities.

Association Between Systolic Blood Pressure and Cardiovascular Inpatient Cost Moderated by Peer-Support Intervention Among Adult Patients With Type 2 Diabetes: A 2-Cohort Study.

OBJECTIVES: People with type 2 diabetes and increased systolic blood pressure (SBP) are at high risk of cardiovascular disease (CVD). In this study, we aimed to investigate the association between CVD-related hospital payments and SBP and tested whether this association is influenced by diabetes peer support. METHODS: Two cohorts comprising people with type 2 diabetes were included in the study. The first cohort comprised 4,704 patients with type 2 diabetes assessed between 2008 and 2009 from 18 general practices in Cambridgeshire and followed up to 2009-2011. The second cohort comprised 1,121 patients with type 2 diabetes from post-trial follow-up data, recruited between 2011 and 2012 and followed up to 2015. SBP was measured at baseline. Inpatient payments for CVD hospitalization within 2 years since baseline was the main outcome. The impact of 1:1, group or combined diabetes peer support and usual care were investigated in the second cohort. Adjusted mean CVD inpatient payments per person were estimated using a 2-part model after adjusting for baseline characteristics. RESULTS: A "hockey-stick" relationship between baseline SBP and estimated CVD inpatient payment was identified in both cohorts, with a threshold at 133 to 141 mmHg, suggesting increased payments for patients with SBP below and above the threshold. The combined peer-support intervention altered the aforementioned association, with no increased payment with SBP above the threshold, and payment slightly decreased with SBP beyond the threshold. CONCLUSIONS: SBP maintained between 133 and 141 mmHg is associated with the lowest CVD disease management costs for patients with type 2 diabetes. Combined peer-support intervention could significantly decrease CVD-related hospital payments.

Mapping intersectional inequalities in biomarkers of healthy ageing and chronic disease in older English adults.

Chronic diseases and their inequalities amongst older adults are a significant public health challenge. Prevention and treatment of chronic diseases will benefit from insight into which population groups show greatest risk. Biomarkers are indicators of the biological mechanisms underlying health and disease. We analysed disparities in a common set of biomarkers at the population level using English national data (n = 16,437). Blood-based biomarkers were HbA1c, total cholesterol and C-reactive protein. Non-blood biomarkers were systolic blood pressure, resting heart rate and body mass index. We employed an intersectionality perspective which is concerned with how socioeconomic, gender and ethnic disparities combine to lead to varied health outcomes. We find granular intersectional disparities, which vary by biomarker, with total cholesterol and HbA1c showing the greatest intersectional variation. These disparities were additive rather than multiplicative. Each intersectional subgroup has its own profile of biomarkers. Whilst the majority of variation in biomarkers is at the individual rather than intersectional level (i.e. intersections exhibit high heterogeneity), the average differences are potentially associated with important clinical outcomes. An intersectional perspective helps to shed light on how socio-demographic factors combine to result in differential risk for disease or potential for healthy ageing.

Educational differences in the influence of health on early work exit among older workers.

OBJECTIVES: Previous research has shown that poor physical and mental health are important risk factors for early work exit. We examined potential differences in this association in older workers (50+) across educational levels. METHODS: Coordinated analyses were carried out in longitudinal data sets from four European countries: the Netherlands (Longitudinal Aging Study Amsterdam), Denmark (Danish Longitudinal Study of Ageing), England (English Longitudinal Study of Ageing) and Germany (German Ageing Survey). The effect of poor self-rated health (SRH), functional limitations and depression on different types of early work exit (early retirement, economic inactivity, disability and unemployment) was examined using Cox regression analysis. We examined educational differences in these effects by testing interaction terms. RESULTS: Poor physical and mental health were more common among the lower educated. Poor SRH, functional limitations, and depression were all associated with a higher risk of early work exit. These health effects were strongest for the disability exit routes (poor SRH: HRs 5.77 to 8.14; functional limitations: HRs 6.65 to 10.42; depression: HRs 3.30 to 5.56). In the Netherlands (functional limitations) and England (functional limitations and SRH), effects were stronger in the lower educated. CONCLUSIONS: The prevalence of health problems, that is, poor SRH, functional limitations and depression, was higher in the lower educated workers. All three health indicators increase the risk of early work exit. In some countries, health effects on early exit were stronger in the lower educated. Thus, lower educated older workers are an important target group for health policy and intervention.

Challenges and practices in promoting (ageing) employees working career in the health care sector - case studies from Germany, Finland and the UK.

BACKGROUND: The health and social care sector (HCS) is currently facing multiple challenges across Europe: against the background of ageing societies, more people are in need of care. Simultaneously, several countries report a lack of skilled personnel. Due to its structural characteristics, including a high share of part-time workers, an ageing workforce, and challenging working conditions, the HCS requires measures and strategies to deal with these challenges. METHODS: This qualitative study analyses if and how organisations in three countries (Germany, Finland, and the UK) report similar challenges and how they support longer working careers in the HCS. Therefore, we conducted multiple case studies in care organisations. Altogether 54 semi-structured interviews with employees and representatives of management were carried out and analysed thematically. RESULTS: Analysis of the interviews revealed that there are similar challenges reported across the countries. Multiple organisational measures and strategies to improve the work ability and working life participation of (ageing) workers were identified. We identified similar challenges across our cases but different strategies in responding to them. With respect to the organisational measures, our results showed that the studied organisations did not implement any age-specific management strategies but realised different reactive and proactive human relation measures aiming at maintaining and improving employees' work ability (i.e., health, competence and motivation) and longer working careers. CONCLUSIONS: Organisations within the HCS tend to focus on the recruitment of younger workers and/or migrant workers to address the current lack of skilled personnel. The idea of explicitly focusing on ageing workers and the concept of age management as a possible solution seems to lack awareness and/or popularity among organisations in the sector. The concept of age management offers a broad range of measures, which could be beneficial for both, employees and employers/organisations. Employees could benefit from a better occupational well-being and more meaningful careers, while employers could benefit from more committed employees with enhanced productivity, work ability and possibly a longer career.

Educational inequalities in health after work exit: the role of work characteristics.

BACKGROUND: Educational inequalities in health have been widely reported. A low educational level is associated with more adverse working conditions. Working conditions, in turn, are associated with health and there is evidence that this association remains after work exit. Because many countries are raising the statutory retirement age, lower educated workers have to spend more years working under adverse conditions. Therefore, educational health inequalities may increase in the future. This study examined (1) whether there were educational differences over time in health after work exit and (2) whether work characteristics mediate these educational inequalities in health. METHODS: Data from five prospective cohort studies were used: The Netherlands (Longitudinal Aging Study Amsterdam), Denmark (Danish Longitudinal Study of Aging), England (English Longitudinal Study of Ageing), Germany (German Aging Study), and Finland (Finnish Longitudinal Study on Municipal Employees). In each dataset we used Generalized Estimating Equations to examine the relationship between education and self-rated health after work exit with a maximum follow-up of 15 years and possible mediation of work characteristics, including physical demands, psychosocial demands, autonomy, and variation in activities. RESULTS: The low educated reported significantly poorer health after work exit than the higher educated. Lower educated workers had a higher risk of high physical demands and a lower risk of high psychosocial demands, high variation in tasks, and high autonomy at work, compared to higher educated workers. These work characteristics were found to be mediators of the relationship between education and health after work exit, consistent across countries. CONCLUSION: Educational inequalities in health are still present after work exit. If workers are to spend an extended part of their lives at work due to an increase in the statutory retirement age, these health inequalities may increase. Improving working conditions will likely reduce these inequalities in health.

Shirt sponsorship by gambling companies in the English and Scottish Premier Leagues: global reach and public health concerns.

While the nature of gambling practices is contested, a strong evidence base demonstrates that gambling can become a serious disorder and have a range of detrimental effects for individuals, communities and societies. Over the last decade, football in the UK has become visibly entwined with gambling marketing. To explore this apparent trend, we tracked shirt sponsors in both the English and Scottish Premier Leagues since 1992 and found a pronounced increase in the presence of sponsorship by gambling companies. This increase occurred at the same time the Gambling Act 2005, which liberalized rules, was introduced. We argue that current levels of gambling sponsorship in UK football, and the global visibility it provides to gambling brands, is a public health concern that needs to be debated and addressed. We recommend that legislators revisit the relationship between football in the UK and the sponsorship it receives from the gambling industry.

Chronic conditions as predictors of later life disability employment exit: a gendered analysis.

OBJECTIVES: Increasing life expectancy has led governments to implement reforms aimed at delaying retirement. Chronic conditions are an important barrier to this given their association with pain, functional limitations, depression and ultimately lower life expectancy. Chronic diseases are gendered in terms of these characteristics, as well as their population prevalence. I examined the extent to which gender moderates the extent to which different chronic conditions lead to disability employment exit, the proportion of exits they account for and key mediators in this process. METHODS: Data from waves 1 to 8 of the English Longitudinal Study of Ageing were analysed. I followed employees aged 50-70 years until they experienced disability employment exit, or were censored. I analysed the influence of chronic conditions, functional limitations, pain, depressive symptoms and subjective life expectancy using discrete time survival analysis. All analyses were carried out separately by gender if a significant interaction was found. The mediation analysis was carried out using the Karlson/Holm/Breen method. RESULTS: No significant gender interactions were found for the risk of chronic conditions on disability employment exit. Lung disease (OR 4.1; 95% CI 2.8 to 5.9), cancer (OR 2.9; 95% CI 2.1 to 4.0) and arthritis (OR 2.6; 95% CI 2.1 to 3.3) were the strongest determinants. Depressive symptoms (OR 3.2; 95% CI 2.5 to 4.1) were also a strong determinant, and along with arthritis, explained a greater proportion of women than men's exits given differences in prevalence. Pain and various types of functional limitations were important mediators of exit as well as determinants in their own right. CONCLUSION: The results suggest that gender differences in the prevalence of different chronic conditions result in differences in the proportion of disability employment exits they account for in the population. Targeted and tailored interventions, for example, in the workplace might take this into account.

Derivation and external validation of risk algorithms for cerebrovascular (re)hospitalisation in patients with type 2 diabetes: Two cohorts study.

AIMS: Cerebrovascular disease is one of more typical reasons for hospitalisation and re-hospitalisation in people with type 2 diabetes. We aimed to derive and externally validate two risk prediction algorithms for cerebrovascular hospitalisation and re-hospitalisation. METHODS: Two independent cohorts were used to derive and externally validate the two risk scores. The development cohort comprises 4704 patients with type 2 diabetes registered in 18 general practices across Cambridgeshire. The validation cohort includes 1121 type 2 patients from a post-trial cohort data. Outcomes were cerebrovascular hospitalisation within two years and cerebrovascular re-hospitalisation within ninety days of the previous cerebrovascular hospitalisation. Logistic regression was applied to derive the two risk scores for cerebrovascular hospitalisation and re-hospitalisation from development cohort, which were externally validated in the validation cohort. RESULTS: The incidence of cerebrovascular hospitalisation and re-hospitalisation was 3.76% and 1.46% in the development cohort, and 4.99% and 1.87% in the external validation cohort. Age, gender, body mass index, blood pressures, and lipid profiles were included in the final model. Model discrimination was similar in both cohorts, with all C-statistics > 0.70, and very good calibration of observed and predicted individual risks. CONCLUSION: Two new risk scores that quantify individual risks of cerebrovascular hospitalisation and re-hospitalisation have been well derived and externally validated. Both scores are on the basis of a few of clinical measurements that are commonly available for patients with type 2 diabetes in primary care settings and could work as tools to identify individuals at high risk of cerebrovascular hospitalisation and re-hospitalisation.

Total/high density lipoprotein cholesterol and cardiovascular disease (re)hospitalization nadir in type 2 diabetes.

Total cholesterol to HDL cholesterol ratio (TC/HDL) is an important prognostic factor for CVD. This study used restricted cubic spline modeling to investigate the dose-response associations between TC/HDL and both CVD hospitalization and CVD rehospitalization in two independent prospective cohorts. The East Cambridgeshire and Fenland cohort includes 4,704 patients with T2D from 18 general practices in Cambridgeshire. The Randomized controlled trial of Peer Support In type 2 Diabetes cohort comprises 1,121 patients with T2D with posttrial follow-up data. TC/HDL and other demographic and clinical measurements were measured at baseline. Outcomes were CVD hospitalization over 2 years and CVD rehospitalization after 90 days of the prior CVD hospitalization. Modeling showed nonlinear relationships between TC/HDL and risks of CVD hospitalization and rehospitalization consistently in both cohorts (all P < 0.001 for linear tests). The lowest risks of CVD hospitalization and rehospitalization were consistently found for TC/HDL at 2.8 (95% CI: 2.6-3.0) in both cohorts and both overall and by gender. This is lower than the current lipid control target, 4.0 of TC/HDL. Reducing the TC/HDL target to 2.8 would include a further 33-44% patients with TC/HDL in the 2.8-4.0 range. Studies are required to assess the effectiveness and cost-effectiveness of the earlier introduction of, and more intensive, lipid-lowering treatment needed to achieve this new lower TC/HDL target.

Social Quality and Health: Examining Individual and Neighbourhood Contextual Effects Using a Multilevel Modelling Approach.

Social quality focusses on the nature of 'the social', arguing that people are realised as social beings through interacting with a range of collectives, both from the formal world of systems and the informal lifeworld. Four conditional factors are necessary for this to occur, which at the same time are assumed to influence health and well-being: socio-economic security, social cohesion, social inclusion and social empowerment. In this paper we test the utility of social quality in explaining self-rated health as a response to arguments that the social determinants of health (SDH) framework often lacks a theoretical basis. We use multilevel models to analyse national English and Welsh data (the Citizenship Survey) to test for both individual- and neighbour-level affects. Our key findings are that (1) neighbourhood contextual (cross-level) effects are present with respect to collective action, personal trust, cross-cutting ties, income sufficiency, and income security; (2) measures of national, community and personal identity as indicators of social cohesion show clear associations with health alongside more common measures such as trust; (3) the security aspects of socioeconomic determinants are especially important (housing security, income sufficiency, and income security); (4) social rights, including institutional rights but especially civil rights have effects of particularly large magnitude. Social quality offers a theoretically-driven perspective on the SDH which has important policy implications and suggests a number of promising avenues for future research.

Development and External Validation of Risk Scores for Cardiovascular Hospitalization and Rehospitalization in Patients With Diabetes.

Context: Cardiovascular disease (CVD) is a common and costly reason for hospitalization and rehospitalization among patients with type 2 diabetes. Objective: This study aimed to develop and externally validate two risk-prediction models for cardiovascular hospitalization and cardiovascular rehospitalization. Design: Two independent prospective cohorts. Setting: The derivation cohort includes 4704 patients with type 2 diabetes from 18 general practices in Cambridgeshire. The validation cohort comprises 1121 patients with type 2 diabetes from post-trial follow-up data. Main Outcome Measure: Cardiovascular hospitalization over 2 years and cardiovascular rehospitalization after 90 days of the prior CVD hospitalization. Results: The absolute rate of cardiovascular hospitalization and rehospitalization was 12.5% and 6.7% in the derivation cohort and 16.3% and 7.0% in the validation cohort. Discrimination of the models was similar in both cohorts, with C statistics above 0.70 and excellent calibration of observed and predicted risks. Conclusion: Two prediction models that quantify risks of cardiovascular hospitalization and rehospitalization have been developed and externally validated. They are based on a small number of clinical measurements that are available for patients with type 2 diabetes in many developed countries in primary care settings and could serve as the tools to screen the population at high risk of cardiovascular hospitalization and rehospitalization.

How do health behaviour interventions take account of social context? A literature trend and co-citation analysis.

In recent years, health behaviour interventions have received a great deal of attention in both research and policy as a means of encouraging people to lead healthier lives. The emphasis of such interventions has varied over time, in terms of level of intervention (e.g. individual vs community) and drawing on different disciplinary perspectives. Recently, a number of critiques have focused on how health behaviour interventions sometimes sideline issues of social context, framing health as a matter of individual choice and, by implication, a personal responsibility. Part of this criticism is that health behaviour interventions often do not draw on alternative social science understandings of the structured and contextual aspects of behaviour and health. Yet to our knowledge, no study has attempted to empirically assess the extent to which, and in what ways, the health behaviour intervention field has paid attention to social context. In this article, we undertake this task using bibliometric techniques in order to map out the health behaviour intervention field. We find that the number of health behaviour interventions has grown rapidly in recent years, especially since around 2006, and that references to social science disciplines and concepts that foreground issues of social context are rare and, relatively speaking, constitute less of the field post 2006. More quantifiable concepts are used most, and those more close to the complexities of social context are mentioned least. The document co-citation analysis suggests that pre 2006, documents referring to social context were relatively diffuse in the network of key citations, but post 2006 this influence had largely diminished. The journal co-citation analysis shows less disciplinary overlap post 2006. At present, health behaviour interventions are continuing to focus on individualised approaches drawn from behavioural psychology and behavioural economics. Our findings lend empirical support to a number of recent papers that suggest more interdisciplinary collaboration is needed to advance the field.

Can peer support be cost saving? An economic evaluation of RAPSID: a randomized controlled trial of peer support in diabetes compared to usual care alone in East of England communities.

BACKGROUND: Diabetes peer support, where one person with diabetes helps others, may improve diabetes management. The objective of this study was to perform a cost analysis of peer support strategies used in RAndomized controlled trial of Peer Support in type 2 Diabetes. METHODS: We performed a 2×2 factorial randomized cluster controlled trial in England. People with type 2 diabetes were invited to participate as either 'peer' or 'peer support facilitator' (PSF) through postal invitation predominantly from general practice. Clusters, based on local communities, were each randomly assigned to one arm of group, 1:1, both group and 1:1 or control interventions. The intervention was delivered over 8-12 months by trained PSFs, supported by monthly meetings with a diabetes nurse. Out-of-pocket expenses/service utilization were self-reported at baseline, midpoint and on trial completion. Intervention costs were collated. Non-hospital costs used National Health Service (NHS) reference costs. Hospital payments were obtained from one local commissioning group and mean payments calculated. The analysis employed a societal perspective. Costs were evaluated at the conclusion of the trial. RESULTS: Participants (n=1299) were recruited across 130 clusters. The four arms were well balanced and matched (60% male, mean diabetes duration 9.5 years, mean glycated haemoglobin (HbA1c) 7.4+/-1.3%, 17% insulin treated). Implementation costs at 2013 rates were £13.84/participant/annum, participant out-of-pocket expenses for any intervention were £11.41/participant/annum and the NHS-incurred costs were reduced by £138.38/participant/annum. Savings for the 1:1, group and any intervention were £233.65, £90.52 and £113.13/participant/annum, respectively. CONCLUSIONS: We conclude that both 1:1 and group diabetes peer support over 8-12 months are cost saving in this setting, although much of the benefit is largely derived by differences in self-reported healthcare utilization. Long-term benefits should be investigated. TRIAL REGISTRATION NUMBER: ISRCTN66963621.