The prevalence of type 2 diabetes (T2D) is rapidly increasing worldwide, and can largely be attributed to the concurrent increase in obesity (Zimmet et al, 2001). Around 80% of people with T2D are obese (Bloomgarden, 2000), and a BMI of 35 kg/m2 has been found to increase the risk of developing T2D by 93-fold in women and by 42-fold in men (Jung, 1997). Both conditions are established cardiovascular (CV) risk factors (Box 1) associated with increased morbidity and mortality (Haslam and James, 2005; Diabetes UK, 2010).
Obesity and T2D have multiple causes and multiple treatment options. Weight management is critical for limiting the development of glucose intolerance and progression from a state of impaired glucose tolerance to diabetes, as well as for optimal management in those who go on to develop T2D. However, a number of current diabetes therapies promote weight gain in an already overweight population (Mitry and Hamdy, 2009). This complexity means that an integrated and coordinated approach, using a dedicated multidisciplinary team focusing on managing both T2D and obesity in a unified manner, is required.
In this article the authors describe the provision of a specialist multidisciplinary diabesity clinic at their hospital, aimed at helping people with coexistent T2D and obesity manage both conditions simultaneously.
The specialist diabesity service in Mid Yorkshire Hospitals NHS Trust
The dedicated specialist diabesity service was initiated in Mid Yorkshire Hospitals NHS Trust in 2007 to address the growing prevalence of people with diabesity in the locality. The aim of the service is to manage the complex healthcare needs of people with diabesity and to address both conditions in a unified way, simultaneously optimising glycaemic control and weight management.
Most clinicians will agree that a multidisciplinary one-stop clinic approach improves patient adherence, thereby simultaneously optimising glycaemic control and weight management. This leads to cost savings in terms of pharmacotherapy usage and healthcare professionals’ time.
The service brings together a multidisciplinary team (MDT) to address the combined and complex needs of people with diabesity, and includes a consultant, diabesity specialist nurse, clinical psychologist, specialist dietitian, physiotherapist, occupational therapist, moving and handling specialist, and a coordinator. With this combined expertise, the service is able to address all aspects of T2D and obesity in a way that optimises the management of both conditions.
Referral to the service
The number of referrals to the diabesity service are increasing every year. It is therefore essential to ensure that robust yet inclusive referral criteria are in place to best serve those in need. At the authors’ institution, people are accepted into the diabesity service if they have T2D with an HbA1c level of >64 mmol/mol (>8%) and a BMI >27.5 kg/m2.
Following referral, individuals undergo initial assessment by the consultant. These measure a range of biometric and psychological parameters, aimed at evaluating the individual’s status with regard to their diabetes and obesity. Box 2 outlines the full scope of these initial assessments.
Initial investigations required on referral
A number of initial investigations are required to give an understanding of the health status of individuals referred to the service. Initial investigations requested include baseline kidney and liver function tests, full blood count and HbA1c level. Endocrine abnormality is an established cause of weight gain in around 10% of people attending the diabesity clinic, and is assessed by using blood tests looking for thyroid dysfunction. If indicated, tests for hypogonadism and hypercortisolism are organised. Sleep patterns and daytime sleepiness are also assessed using the Epworth Sleepiness Scale (Johns, 1991); if the score is ≥10, patients are referred for sleep study to rule out obstructive sleep apnoea. Patients are also asked to complete food, blood glucose and hunger pattern diaries and to bring them to each appointment. An extended glucose tolerance test is undertaken if reactive hypoglycaemia is suspected.
MDT approach to diabesity
Each member of the MDT provides specialist support. The diabesity specialist nurse plays a vital role within a successful diabesity service and provides specialist expertise in delivering nurse-led clinics to ensure: appropriate and supported pharmacotherapy initiation; monitoring and evaluation of treatment plans; management of people with diabetes, before and after bariatric surgery; audit; and protocol, guideline and service development. The diabesity specialist nurse also evaluates the patient’s blood glucose, food and hunger pattern diary during each visit. This collaborative approach enables the healthcare professional and patient to set specific and appropriate goals in relation to glycaemic control and weight management (Radimer et al, 1990).
The specialist dietitian has an important role in offering behavioural therapy and advice on very-low-calorie diets to aid weight loss. Education is also provided regarding carbohydrate and its effect on blood glucose levels.
The consultant and the diabesity specialist nurse work closely with the clinical psychologist. Patients identified as likely to benefit from psychological support after basic cognitive behaviour therapies are referred to the psychology service. Patients are encouraged and trained to identify the differences between cravings and hunger and to use this understanding to modify their food intake.
The physiotherapist provides an exercise programme tailored to each person’s ability and comorbidities. Working alongside the diabesity specialist nurse, the physiotherapist encourages dose alteration for insulin and oral antidiabetes drugs, based on physical activity and blood glucose levels.
Clinical management of diabesity
Weight reduction is fundamental for managing obese people with T2D (Box 3). Members of the MDT work together in addressing not only weight and glycaemic control but also obesity- and diabetes-related complications (Department of Health, 2001; Kentz and Bailey, 2005). Interventions are holistic and tailored to the specific circumstances of each person; after initial assessment, investigation and treatment of underlying endocrine abnormalities, focus is then shifted to identifying hunger patterns and assessing any underlying psychological issues.
Pharmacotherapy
Multiple therapeutic options are available for treating diabesity, a number of which promote weight gain – such as insulin, sulphonylureas, thiazolidinediones and glinides (Mitri and Hamdy, 2009) – thereby exacerbating underlying weight problems and adversely affecting CV risk (Russel-Jones and Khan, 2006). Insulin-induced weight gain in particular is caused by conservation of calories previously renally excreted, combined with patients often increasing their calorie intake to defend against hypoglycaemia. However, by reducing insulin dose appropriately, in conjunction with an integrated approach using diet and exercise, weight gain with insulin therapy can be minimised (Russel-Jones and Khan, 2006).
Individualising pharmacological interventions is therefore key, with a view to optimising glycaemic control while simultaneously addressing weight management issues. To this end, a number of new drug therapies are available for the treatment of T2D that are either considered weight-neutral (dipeptidyl-peptidase-4 [DPP-4] inhibitors) or associated with weight loss (glucagon-like peptide-1 [GLP-1] receptor agonists) (Mitri and Hamdy, 2009; NICE, 2009). Patients should be supported by the healthcare professional in the use of such medicines (Phelan and Wadden, 2002) and advised on side-effects. In addition, it is important to stress to patients that these drugs are merely a tool to be used in conjunction with lifestyle and dietary modification.
Support and self-management
The diabesity specialist nurse and patient work in partnership to promote self-management. Patients are encouraged to identify their hunger patterns and support is then provided to understand and reset these. A useful tool is motivational interviewing, which is a person-centred, semi-directive method for enhancing intrinsic motivation to change by exploring and resolving ambivalence (Silverman, 1998; Miller and Rollnick, 2002).
Self-management is a vital concept within the diabesity clinic. Patients are encouraged to attend the Expert Patients Programme and DESMOND (Diabetes Education and Self Management for Ongoing and Newly Diagnosed) programme, which are available locally. These offer patients information and the skills to effectively manage their condition (Diabetes UK and DH, 2005).
Coping strategies during stress and techniques for distraction should also be discussed to deal with cravings, which commonly last for about 30 minutes in duration (Kohsaka and Bass, 2007). This method can help in reducing portion size and comfort eating.
Conclusion
The complex aetiological interrelationship between obesity and T2D makes a strong case for a unified clinic under the management of a multidisciplinary healthcare professional team. Such an approach places the person with coexistent T2D and obesity at the centre of their care, treating both conditions simultaneously, rather than two conditions in isolation. In order to deliver such a service, there needs to be a collaborative effort across traditional organisational divides.
