With updates to NICE guidance and plans for GPs to roll out a new weight-loss drug, the focus on obesity and weight management is intensifying. Advanced nurse practitioner Wendie Smith explains why it is important to address overweight and obesity at every opportunity – and how nurses in primary care can best approach this sensitive issue
Obesity is a complex condition with multifactorial causes that include ethnicity, genetics and socioeconomic factors. It is important to understand each person’s potential causes and risks, to help them address it.
General practice nurses (GPNs) are well positioned to initiate conversations about obesity with patients. Mental health and body image play key roles, and discussions about these topics in clinic should be approached with empathy and without judgement.
Following the introduction of the obesity strategy in 2020, NICE has now issued an update to its guidance on obesity and overweight, consolidating several sets of guidelines. Importantly NICE has also recommended that the new injectable drug tirzepatide should be prescribed in general practice. It is important for GPNs to keep up to date with these developments and understand how they can support patients with weight loss.
Overweight and obesity – a growing concern
As nurses will be aware, rates of overweight and obesity in the developed world have been rising for decades. Recent Government statistics for England show that in the year to November 2022, 64% of adults aged 18 and over were overweight or living with obesity. Overweight and obesity affects some groups disproportionately, with 71% of black adults found to be overweight or obese – the highest percentage out of all ethnic groups. By contrast, the lowest proportion was seen in adults from the Chinese ethnic group, of whom 33% were overweight or living with obesity.
Looking back, over the six years up to November 2022, the percentage of white British adults who were overweight or living with obesity went up from 62% to 65%; it also went up for adults in mixed ethnic groups, from 54% to 60%.
Why is it so important to address obesity?
Complications of being overweight and obesity include health issues such as type 2 diabetes, hypertension, some cancers, fertility problems, mental health issues and mobility challenges.
Recent research has shown that even ‘healthy’ obese individuals have a higher risk of heart disease compared to lean individuals, busting the popular myth that you can be ‘fat but fit’.
We also know obesity puts people at higher risk of developing health problems in the future – fortunately evidence shows that even a relatively modest reduction of 5% in body weight can lead to significant health benefits and should be encouraged.
There is also stigma related to being overweight, based on beliefs that it is down to lifestyle choices. While this may be true in some cases, developing a therapeutic relationship is key to addressing this very sensitive subject.
What do we mean by overweight and obesity?
The terms ‘overweight’ and ‘obesity’ are used to describe excess body fat. Being overweight or obese results from an imbalance between energy intake and energy expenditure.
Weight is categorised by a person’s body mass index (BMI), calculated by dividing their weight (in kg) by the square of their height (in m2).
The categories of overweight and obesity in adults are defined as follows:
• healthy weight: BMI of 18.5–24.9 kg/m2.
• overweight: BMI of 25–29.9 kg/m2.
• obesity 1: BMI of 30–34.9 kg/m2.
• obesity 2: BMI of 35–39.9 kg/m2.
• obesity 3: BMI of 40 kg/m2 or more.
In people with a South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean family background, who are more prone to central fat, and at heightened risk from overweight at lower BMIs, the following lower thresholds for overweight and obesity should be used:
• Overweight: BMI 23 kg/m2 to 27.4 kg/m2.
• Obesity: BMI 27.5 kg/m2 or above.
Obesity classes 2 and 3 are then usually identified by reducing the above thresholds for White people by 2.5 kg/m2.
However, BMI should be interpreted with caution especially in those with a higher muscle mass, such as athletes, in whom it tends to overestimate body fat, and in people over 65 in whom a slightly higher BMI may have a protective effect. Its sensitivity in men and women is also variable.
NICE highlights the importance of central adiposity and how this is associated with increased risks of health problems like hypertension, diabetes and heart disease. Therefore in those with a BMI below 35kg/m2, it is important to also routinely measure waist-to-height ratio to estimate central adiposity and help predict risk.
The degree of central adiposity based on waist-to-height ratio is classified as follows:
• healthy central adiposity: waist-to-height ratio 0.4 to 0.49, indicating no increased health risks.
• increased central adiposity: waist-to-height ratio 0.5 to 0.59, indicating increased health risks.
• high central adiposity: waist-to-height ratio 0.6 or more, indicating further increased health risks.
People should also be encouraged to take their own measurements, with general advice to keep their waist measurement to under half their height (waist-to-height ratio <0.5).
In children and young people, NICE advises that accurate classification requires weight to be considered relative to BMI percentiles. We should also routinely measure waist-to-height ratio in children, using the same definitions for central adiposity as described above for adults.
Discussing results with patients
Once you have assessed someone’s overweight or obesity class and central adiposity risk, NICE advises you should assess any comorbidities and other risk factors, to establish those who are most at risk due to their weight and may need referral for specialist care.
It is also key to discuss any drivers of obesity – including social factors, stigma and mental health. In my view this is very helpful as it acknowledges that the factors contributing to weight gain can be complex. Practice nurses understand their patient demographic and environmental factors in their community, and tailoring care is a key skill that practice nurses bring to these consultations.
Explain to the patient their level of overweight or obesity and central adiposity, and how this may impact their health including their risk of developing other long-term conditions – such as type 2 diabetes, cardiovascular disease, hypertension and certain cancers, as well as respiratory, musculoskeletal illnesses, and metabolic conditions such as non-alcoholic fatty liver disease.
Discussing personalised goals that are achievable and can be maintained long term is key. This may include appropriate referral, including to a more specialised service for those with weight-related comorbidities, or who have complex needs such as learning disability. However, as some people may not be keen on taking up a referral, it is still important to provide them with all the information they need to achieve and maintain a healthy weight and BMI for a healthy lifestyle.
How can GPNs approach this?
NICE advises we should take opportunities to assess and identify overweight and obesity, by measuring BMI and waist-to-height ratio, when people register with a GP, and also during routine consultations for long-term conditions (such as type 2 diabetes) and other routine health checks.
However, nurses in primary care will know how challenging it can be to open a conversation about weight in a busy clinic.
Public Health England (now under the auspices of UKHSA) advocated the ‘Ask, Advise and Assist’ approach as a brief intervention. This is a very manageable approach we can take while doing other tasks in a consultation, which I find very useful in practice.
The three-step approach is as follows
- Ask permission to discuss weight, being non-judgemental and exploring the patient’s readiness for change. Simple questions to initiate the conversation might be: ‘Before you leave, could I check your weight today?’; or ‘While you’re here, can I check your weight?’ If they agree, you can measure the person’s height, weight and waist circumference, to determine their obesity stage.
- Advise on the benefits of modest weight loss, and how this can be more achievable with support. Explain what specific services are available to them and offer referral. For example, ‘One of the best ways to lose weight is with support and [named local weight management service] is available free. I can refer you now if you want to give it a go?’
- Assist the patient to commit to action and leave with a plan in place, by making a referral to the service you have agreed on and offering ongoing support. If they are receptive you can let them know the next steps – for example, ‘I will refer you to the service now. You’ll get an appointment through the post’ – and suggest a follow-up appointment – for example, ‘I’d like to see how you’re getting on, so next time you come to see me, I will weigh you again and we can talk some more’.
If the patient is non-committal, or doesn’t want to engage at all, accept their wishes and acknowledge their concerns but also re-offer our support for a future time. Whatever the outcome, remember to make a note in the patient’s records about the discussion and what follow up is needed.
This handy infographic provides a useful reminder of this approach in summary.
In my experience people do want to talk about their weight and health, and using motivational approaches are most effective when there is a therapeutic relationship, which GPNs develop over years with their patients.
It’s essential to be understanding of patients who may be reluctant to be measured or find discussions about weight triggering. Providing support, communicating with empathy, and respecting patients’ decisions is key in managing obesity. The therapeutic relationships nurses have with their patients can mean any intervention has an impact, even if you don’t get past the first step initially.
While not everyone wants the information my preferred line is ‘the door is always open if you want to discuss this further, just make an appointment if you want more information”
It’s important to explain that managing weight can improve long-term physical and mental health. In addition, using a manageable 5% of body weight loss offers a realistic first step. It is also essential to be familiar with the weight loss services in your area and what the referral criteria are.
While regular follow up can be challenging in general practice, it is vital to provide resources and ensure referral to specialist services where needed, especially when the BMI is above 50.
Pharmacological options for obesity
The landscape for obesity medication is changing rapidly, following NICE’s recent recommendation that the new injectable weight-loss drug tirzepatide should be prescribed by GPs on the NHS.
Tirzepatide (brand name Mounjaro) is recommended, alongside a reduced calorie diet and increased physical activity, in adults with:
• an initial BMI ≥35kg/m2 (usually reduced by 2.5kg/m2 in people from South Asian, Chinese, other Asian, Middle Eastern, Black African or African-Caribbean ethnic backgrounds) and
• at least one weight-related comorbidity.
This is based on evidence that over 96% of people receiving tirzepatide treatment, alongside diet and exercise advice, lost 5% or more of body weight over 6 months, compared with just 28% of people receiving diet and exercise advice alone.
The drugs liraglutide (marketed under the brand name Saxenda for weight loss) and semaglutide (Wegovy for weight loss) – both already established for use in glucose-lowering in type 2 diabetes – continue to be recommended in obesity under certain criteria, but these will still only to be available from specialist services, rather than being prescribed in primary care.
Another weight-loss treatment, orlistat, is also still available in both primary and secondary care settings, as well as from pharmacies at a lower dose. It has gastrointestinal side effects, including diarrhoea, which can be unacceptable to some.
Importantly, all these weight-loss medications are only recommended in people who have so far failed to lose enough weight through dietary, activity and behavioural changes, and must only be taken alongside diet and exercise plans.
NHS England has advised the treatment will have to be rolled out gradually, to allow GP practices to cope with demand, although there are still concerns about how this will be managed practically.
However, with appropriate resourcing, practice nurses would be well placed to offer the management of weight loss medications with structured follow-up.
Key points
• GPNs play a crucial role in addressing obesity and helping patients to be aware of their risks of weight related health issues.
• Remember that risk varies for different ethnic groups and measuring waist is important for those with BMI below 35.
• Using a structured approach, such as the ‘three As’, when addressing obesity can help maintain therapeutic relationships and ensure interventions are effective.
• Injectable weight-loss drugs are set to become much more widely available in primary care with the roll-out of tirzepatide in general practice, and GPNs will likely play a role in supporting this.
Wendie Smith is a locum advanced nurse practitioner in Bristol
