Establish why the patient has consulted now
Factors triggering the consultation may include a recent diagnosis of obesity-related morbidity such as type 2 diabetes, or a close relative’s death from obesity or related psychosocial comorbidities. Exploring the patient’s reasons and motivation for attendance will allow
a more focused consultation and offer the chance for you to agree a plan that addresses the patient’s individual needs.
History
It is common for overweight or obese individuals to have experienced several weight reduction attempts in the past. These previous attempts should be explored as they could provide useful information on the individual, such as positive motivational factors, previous frustrations experienced, expectations and personal beliefs.1 The amount of weight lost, gained or regained from previous attempts provides insight
about successes or failures and patient expectations. Potential barriers or positive factors can be focused on and addressed early in the treatment plan.1
Assessment
• Rule out rare causes of obesity such as hypothyroidism, Cushing’s syndrome and metabolic problems such as polycystic ovarian syndrome.
• Assess cardiovascular risk factors. Obesity is a well-recognised risk factor for several chronic diseases such as hypertension, diabetes, obstructive sleep apnoea, dyslipidaemia and non-alcoholic fatty liver disease (NAFLD). Sleep apnoea can be screened for using validated questionnaires.
• Medication review – some medications can affect the appetite centre or reduce metabolic rate (see box below).
• Smoking cessation advice should be given as part of a CV risk assessment. The Framingham Heart Study has shown that overweight and obese individuals who smoke have a significantly lower life expectancy compared to non-smokers, but smoking cessation can lead to weight gain, especially in women. Nicotine or chewing gum can help to prevent snacking while bupropion is associated with weight reduction.
• Advice on cutting down alcohol intake.
• Simple weight loss advice can be given such as reducing portion sizes, avoiding second servings and, if possible, increasing physical activity. It is also very important to set achievable goals, as patients often have unrealistic expectations. The recommended weight reduction is 0.5–1Kg (1-2lb) per week.1
It is also important for GPs to have a good understanding of the referral process for local specialist medical weight management services and have access to a dietician with a special interest in weight management.
Clarifying the patient’s expectations (outcomes)
Studies have found a difference in opinions between doctors and patients regarding successful weight loss. It is vital that information on recommended weight loss is given to patients on their first visit to prevent later development of negative emotions and attitudes. The target weight reduction is usually 5–10% within six months as this has been shown to be achievable and can lead to significant improvements in CV risk factors such as glycaemic control. Success can also be assessed on functional capabilities such as ability to walk, climb stairs or play with children.
Management
Multidisciplinary management of overweight and obese individuals is important because there is no one-stop treatment. The Lighten Up trial has shown that commercial weight loss programmes may be more effective and cheaper than primary care weight management services.2 Including a GPSI in weight management or a bariatric physician and a dietician with special interest in weight management in
a multidisciplinary team is essential in providing comprehensive and holistic support to patients. NICE states that patients with severe obesity (BMI ≥40kg/m2) are likely to need specialist medical weight management assessment and possibly bariatric surgery.3
Pharmacotherapy
There are limited options for anti-obesity medication. Currently, only orlistat is licensed for weight management. This drug has been shown to result in a modest average weight reduction of about 5kg.4 NICE recommends that the use of orlistat should be in addition to lifestyle intervention, meaning patients should receive dietary and lifestyle advice alongside the prescription. The use of orlistat can be continued beyond one year for weight maintenance as weight regain frequently occurs after 12 months. Because of its effect on fat absorption in the gut, there is a potential malabsorption of fat-soluble vitamins such as vitamin D.
Common medications associated with weight gain1
- Anticonvulsants such as sodium valproate, carbamazepine, gabapentin
- Antipsychotics such as clozapine, olanzapine, risperidone, quetiapine
- Antidepressants such as tricyclic antidepressants, SSRIs, mirtazapine
- Antihypertensives such as ß-blockers, calcium channel blockers
- Hypoglycaemic medication, for example insulin, sulfonylurea, thiazolidinedione
- Other medications including steroids, antihistamines, tamoxifen or lithium
Bariatric surgery
Bariatric surgery has been shown to be beneficial in many ways:
• lower incidence of CV problems and deaths
• improvements in CV risk factors such as diabetes, hypertension and dyslipidaemia
• weight reduction of between 20-32%
in two years and 10-25% after five years
• improved quality of life, including general and weight-related quality of life, depression scores, self-esteem and physical activity
• cost-effectiveness for the NHS.
Bariatric surgery also carries risks. Operational risk is low and similar to common procedures such as laparoscopic cholecystectomy. Nutritional deficiencies are associated post-operatively with the gastric bypass and sleeve gastrectomy, and these patients are likely to need lifelong vitamin and mineral supplementation.
There is a dearth of information on the long-term outcomes of bariatric surgery. Although CV and cancer mortality improve after bariatric surgery, post-surgical patients seem to have a slightly higher suicide rate. Only the Swedish Obese Subjects (SOS) study has reported outcomes after 10 years of follow-up.5 It showed that diabetes remission rates decreased from 72% at two years to 36% at 10 years. Therefore, patients should continue to have an annual diabetes review.
Referral for surgery
NICE CG43 has set criteria for bariatric surgery that are followed throughout England, recommending bariatric surgery for patients who have BMI ≥40kg/m2 or ≥35kg/m2 with a significant disease after at least six months of unsuccessful specialist medical weight management. For those who have BMI ≥50kg/m2, bariatric surgery is recommended as a potential first-line treatment option.
Ways around an impasse
Some patients experience difficulties with even minimum levels of weight reduction. When this occurs, it is important to review medication, dietary plans, psychological state, social circumstances and treatment options.
Poor or difficult adherence to dietary plans may occur, and fundamental reasons behind this are usually complex. Concomitant challenging emotional and psychological conditions such as depression may contribute. Psychological support should be available for patients from a clinical psychologist or psychiatrist. On rare occasions an underlying eating disorder may be concealed from the practitioner.
For severely obese patients, bariatric surgery seems to be the most effective treatment for weight reduction and these patients should be referred to local specialist bariatric services.5
Dr Shahrad Taheri is a consultant physician and lead for weight management and bariatric services at the Heart of England NHS Foundation, Birmingham.
Dr Wen Bun Leong is a clinical research fellow at the Heart of England NHS Foundation Trust
