Prostate news article, July 2009

MORE PRO–ACTIVITY IS REQUIRED IN THE BATTLE AGAINST OBESITY IN MEN   Article by:   Professor Roger Kirby, Chairman, Prostate UK

The incidence of obesity worldwide continues to increase alarmingly. Obesity has a major impact on the health of the individual and if left untreated can lead to a number of diseases, including the metabolic syndrome, hypertension, diabetes, osteoarthritis, as well as benign prostatic hyperplasia¹ (BPH) and prostate cancer². Moreover, it may also have a psychological impact leading to low self-esteem and reduced quality of life. Since the urologist is very often the first specialist a middle-aged male may encounter as a patient, he or she is in a unique position, not only to assess the extent of central obesity and evaluate associated co-morbidities, but also inspire the individual to set in motion corrective measures designed to achieve a realistic target reduction of 5–10% of the patient's original weight.

Obesity is already major problem in the UK, and one which already affects 29% or so of men. The incidence of diabetes in the USA is approaching 10% in some states, and the situation is deteriorating in many other countries³. However, the battle against obesity is not a hopeless case. Motivation and behavioural change provide the foundation to successful weight reduction, and importantly, its maintenance over time. Urologists, as advocates of Men's Health, can provide the motivation and inspiration for a radical change of lifestyle in their patients'. Very often, significant effort and resources are wasted on diet-based weight loss solutions that do not support long-term behavioural modification. A successful intervention for weight management must adopt a holistic approach and be developed by on-going negotiation between the person and his clinician.

Body mass index (BMI) should be used as a measure of obesity, but needs to be interpreted with caution, because it is not a direct measure of obesity. Waist circumference, measured at the level of the umbilicus, not where the belt is worn, is a useful and easy supplement to BMI. Significantly, this value is one that is often severely underestimated by patients. Raising the issue of obesity for the first time during a consultation may provoke surprise, anger, denial or disbelief. The National Institute for Clinical Excellence (NICE) guideline suggests that several areas should be explored, in particular the person's view of their weight gain, possible reasons for it, eating patterns and exercise levels together with beliefs and attitudes to these subjects⁴. Following these discussions an assessment of the psychosocial or psychological distress associated with lifestyle, environment and family factors should be made, including a family history of obesity. An integral part of the evaluation is a review of co-morbidities which may include type 2 diabetes, hypertension, dyslipidaemia and sleep apnoea.

Achieving behavioural change requires an agreement about realistic goals and actions. Skilful and sensitive communication is required, avoiding jargon and most importantly using praise and encouragement to underline successes, however small. A series of strategies, tailored to the individual, should be deployed which may include self-monitoring of behaviour and progress, stimulus control, goal setting and a slower rate of eating. In men particularly, reducing the amount of alcohol consumed in the evenings can be critical. The health benefits of exercise should be underlined. Men should be encouraged to do at least 30 minutes, or preferably longer, moderate-intensity physical activity on five or more days per week. To actively lose weight and maintain the benefit patients should be advised that 60–90 minutes of moderate-intensity exercise per day may be necessary; ideally in two separate bouts each day. The rationale for twice daily exercise stems from the observed increase in basal metabolic rate which lasts up to 15 hrs after each session, and this obviously enhances its weight reduction potential. The possibility of acquiring exercise equipment, such as a rowing machine or cross trainer, to use at home should be discussed.

Men should be encouraged to improve the overall healthiness of their diet. The main requirement of a dietary approach to weight loss is, self–evidently, that total energy intake should be less than energy expenditure. A diet that has a 600Kcal/day deficit, especially one that reduces fat intake is often recommended. Low–calorie diets (1000–1600 kcals/day) may be considered, but are less likely to be nutritionally complete; very–low–calorie diets (<1000 kcals/day) should not be used for more than 12 weeks continuously. If this sort of dietary approach is successful, it is critical that the nutritional modifications are included into ongoing lifestyle change, to discourage the regain of weight.

Several approved and evidenced-based pharmacological interventions are now available for the treatment of obesity. Orlistat is licensed for use as part of an overall plan for managing obesity in adults with a BMI of 30 Kg/m2 or 28Kg/m2 plus associated risk factors, such as diabetes. Orlistat reduces the absorption of dietary fat by inhibiting gastrointestinal lipase. Two systematic reviews that evaluated patients who had taken orlistat for one year as well as eating a low calorie diet and/or exercising have shown a mean weight reduction of 8.1 kg5 . This weight reduction was 2.8Kg more than those who had taken placebo^5,6. The most frequent adverse effects experienced with orlistat are gastrointestinal and result from the blockage of intestinal fat breakdown and absorption and include oily leakage from the bowels, liquid stools, flatulence and abdominal discomfort.

Sibutramine acts centrally by enhancing satiety and attenuating the adaptive decline in resting metabolic rate during weight loss. It works most effectively when combined with a counselling strategy that achieves behavioural change. Like orlistat, it should only be continued beyond 3 months in patients who have achieved at least a 5% reduction in their body weight since starting drug treatment. Blood pressure and pulse should be monitored during treatment. The most frequent side–effects include dry mouth, constipation,and insomnia^7,8,9.

Rimonabant was until recently licensed as an adjunct to diet and exercise for the treatment of obese patients (BMI >30kg/m2) or overweight patients (>27kg/m2) with associated risk factors such as dyslipidaemia. It is a selective cannbinoid–1 receptor antagonist acting on the endocannabinoid, which influences energy balance, glucose and lipid metabolism and body weight, and the intake of highly palatable, sweet or fatty foods. One meta–analysis of 4 clinical trials with rimonabant has shown that a year's treatment at a dose of 20mg/day reduces body mass by a mean of 4.9kg more than placebo or about 5% of baseline body weight. This was associated with improvements in weight circumference, high density lipoprotein (HDL) cholesterol triglyceride levels and blood pressure. The most frequent side‏effect with rimonabant is nausea but depression may also occur¹⁰. The latter problem is the main reason for its recent withdrawal. Surgical intervention should only be considered in patients in whom all appropriate non–surgical measures have been tried and failed and who have a BMI of 40 kg/m² or more or 35kg/m² and other significant disease such as diabetes that could be improved if they lost weight. Bariatric surgery may also recommended as a first-line option instead of lifestyle interventions or drug therapy in those with a BMI of >50kg/m². The procedures used include adjustable silicone gastric banding and gastric bypass and are best employed by specialist units with an extensive experience with the techniques.

In conclusion, obesity is becoming an epidemic problem which is destined to afflict more and more of our patients. Rather than ignored, the issue should be addressed pro-actively as part and parcel of the original prostatic or erectile dysfunction (ED) problem that brings the patient into the sphere of the urologist. If any urological surgical intervention is contemplated a weight reduction programme can have a significantly beneficial impact on the outcome. If ED is the presenting symptom, weight reduction may significantly reduce associated cardiovascular risk and may even improve the ED. During follow-up positive messages about the benefits of maintaining the lifestyle modifications that resulted in the original loss of weight can be reinforced. This more holistic approach befits modern urology and the urologist, and seems to be the way ahead as we continue to expand our role to encompass the broader specialty that constitutes Men's Health¹¹.

References:
1. Nandeesha H, Benign prostatic hyperplasia: dietary and metabolic risk factors. Int J Nephrol 2008;40:649-56.

2. Goldstraw M, Beserani D, Amoroso P, Kirby RS, Is obesity a risk factor for prostate cancer? BJU Int 2007;100:726–8.

3. National Institute for health and Clinical Excellence, National Collaborating Centre or Primary Care. Obesity: the prevention, identification, assessment and management of overweight and obesity in adults and children. http://guidance.nice.org.uk/CG43/guidance.

4. Mokdad AH, Ford ES, Bowman BA, et al. Prevalence of obesity, diabetes and obesity–related health risk factors JAMA 2003;289:76–9.

5. Li Z, Maglione M, Tu W, et al Meta–analysis: pharmacological treatment of obesity. Ann Int Med 2005;142:532–46.

6. Hutton B, Fergusson D Changes in body weight and serum lipid profile in obese patients treated with orlistat in addition to a hypocalorific diet: a systematic review of randomised clinical trials. Am J Clin Nutr 2004;80:1461-68.

7. Arterburn DE, Crane PK, Veenstra DL, The efficacy and safety of sibutramine for weight loss: a systematic review. Arch Int Med 2004;164:994–1003.

8. Waddern TA, Berkovitz RI, Womble LG, et al randomised trial of lifestyle modification and pharmacotherapy for obesity. N Engl J Med 2005; 353:2111–20.

9. Gokcel A, Gumurdulu Y, Karakose H et al Evaluation of the safety and efficacy of sibutramine, orlistat and metformin in the treatment of obesity Diabetes, Obes Metab 2002;4:49–55.

10. Curioni C, Andre C, Rimonabant for overweight and obesity. Cochrane database of systematic reviews, 2006.

11. Kirby RS, Kirby MG, Amoroso P, Dean J, Gould D, Steps by which better health for men could be achieved. B J U Int 2006;98:285–8.