download PDF
full article:
Dear Editor
We would like to draw your attention to the fact that obesity and osteoarthritis (OA) are both major health problems in Australia. A recent prevalence study demonstrated that 67% of Australian men, and 52% of Australian women have a Body Mass Index (BMI) exceeding 25 kg/m-21. Alarmingly, one-quarter of Australian primary school students are overweight or obese2,3 and the rate of Australian obesity is increasing4. Osteoarthritis is the third leading cause of disease-burden, measured as disability-adjusted life years in the developed world, and is predicted to increase over the coming decades4. Obesity is arguably the most important modifiable risk factors for knee OA5,6. By 2016, it is estimated that there will be a 50% increase in the prevalence of Australian obesity4, which is likely to further compound the burden of knee OA. Already, the workplace cost of musculoskeletal diseases is highest among people with a BMI of 27.5 kg/m2 or greater7. Since OA further impairs mobility, the arthritic population may struggle to effectively control their weight through exercise, setting up a vicious disease cycle.
Geographically, the prevalence of obesity tends to be higher in rural rather than urban populations. In regional Australia in 2001, males were 1.05 and females 1.10 times more likely to be overweight or obese when compared with their urban counterparts8. Indigenous Australians in remote communities have also been shown to have a larger BMI than the general population8,9. Given the limited and costly access to health services in regional Australia10, the obesity epidemic threatens to have detrimental implications for rural health and, therefore, the national healthcare system. For example, in the context of OA, the risk for knee joint replacement is greater in people who are obese11. Currently, considerable waiting lists for joint replacement secondary to OA exist in Australia, and prolonged waiting for joint replacement has been associated with significant psychological distress12. The obesity epidemic threatens to further compound surgical waiting times, particularly in rural settings, where access to health services is limited.
Weight management, therefore, becomes crucial to the prevention and management of knee OA. For each additional kg/m2 increase in people whose BMI is greater than 27, there is a 15% increased risk for knee OA5. Moreover, weight loss can help prevent OA. When 64 women with confirmed radiographic knee OA were compared with women without the disease, a reduction in the BMI of two or more units over the 10 years before follow up decreased the odds for developing knee OA by over 50% (OR 0.46; 95% CI 0.24 to 0.86)6. People with a high risk for OA, defined by elevated baseline BMI (>25 kg/m2), also decreased their risk for the onset of OA by weight loss of 2 or more BMI units (OR 0.41)6. Furthermore, people with knee OA who lose weight report a reduction in knee pain13 and demonstrate functional improvement14.
How to best promote weight management in the rural setting is challenging. Although a recent survey that included patients from rural Australia demonstrated that 78% of respondents thought that GPs had a role in weight management, only 46% of patients thought that GPs would have enough time to focus on giving weight-loss advice15. Indeed, 72% of the doctors stated that they had limited time to provide dietary counselling16. Moreover, 72% of doctors felt ill-prepared to give dietary counselling, while 95% lacked confidence in their ability to help patients make meaningful dietary changes16. These data indicate the need for primary healthcare physicians to receive further weight management training, as well as prioritising weight management among their communities.
Preventative measures are also required to help curtail Australian adult obesity. In particular, children and adolescents must be targeted. An Australian study demonstrated excessive amounts of energy-dense foods in school lunchboxes, and it was recommended that health promotion target school-based diets of Australian children17. Reviews of school canteen menus by dieticians, as well as incorporating dietary advice and exercise into the school curriculum may prove beneficial. Nevertheless, a recent systematic review examining interventions for preventing childhood obesity concluded that studies that focused on combining dietary and physical activity approaches did not significantly improve BMI18. However, the authors recommended that the appropriateness of development, design, duration and intensity of interventions to prevent childhood obesity need to be reconsidered, alongside comprehensive reporting of the intervention scope and process.
The effects of obesity on musculoskeletal diseases such as OA are often overlooked, despite evidence that maintaining an ideal body weight benefits joint health5,6,13,14. Given the increasing rates of obesity in rural Australia, as well as the reduced access to health professionals, the obesity epidemic is likely to have a major impact on rural health. In the context of both OA and other health and social issues, it is important that the potential medium- and long-term impact of rising obesity rates on rural communities are not forgotten and strategies are implemented to address such issues.
Andrew J Teichtahl, BPhysio(Hons)
Yuanyuan Wang, MD
Flavia M Cicuttini, FRACP, PhD
Department of Epidemiology and Preventive Medicine, Monash University,
Central and Eastern Clinical School, Alfred Hospital,
Melbourne, Victoria, Australia
References
1. Thorburn AW. Prevalence of obesity in Australia. Obesity Review 2005; 6: 187-189.
2. Wake MA, McCallum Z. Secondary prevention of overweight in primary school children: what place for general practice? Medical Journal of Australia 2004; 181: 82-84.
3. Booth ML, Wake M, Armstrong T, Chey T, Hesketh K, Mathur S. The epidemiology of overweight and obesity among Australian children and adolescents, 1995-97. Australian and New Zealand Journal of Public Health 2001; 25: 162-169.
4. Public Health Department. Victorian burden of disease study: morbidity. Report no. 4: Melbourne: Victorian Government Department of Human Services, 2004.
5. Anderson JJ, Felson DT. Factors associated with osteoarthritis of the knee in the first national Health and Nutrition Examination Survey (HANES I). Evidence for an association with overweight, race, and physical demands of work. American Journal of Epidemiology 1988; 128: 179-1789.
6. Felson DT, Zhang Y, Anthony JM, Naimark A, Anderson JJ. Weight loss reduces the risk for symptomatic knee osteoarthritis in women. The Framingham Study. Annals of Internal Medicine 1992; 116: 535-539.
7. Burton WN, Chen CY, Schultz AB, Edington DW. The economic costs associated with body mass index in a workplace. Journal of Occupational and Environmental Medicine 1998; 40: 786-792.
8. Australian Institute of Health and Welfare. Rural, regional and remote health, indicators of health. Rural health series no. 5. Canberra: Australian Institute of Health and Welfare, 2005.
9. Wang Z, Hoy WE. Hypertension, dyslipidemia, body mass index, diabetes and smoking status in Aboriginal Australians in a remote community. Ethnicity in Diseases 2003; 13: 324-330.
10. Young AF, Dobson AJ. The decline in bulk-billing and increase in out-of-pocket costs for general practice consultations in rural areas of Australia, 1995-2001. Medical Journal of Australia 2003; 178: 122-126.
11. Wendelboe AM, Hegmann KT, Biggs JJ, Cox CM, Portmann AJ, Gildea JH et al. Relationships between body mass indices and surgical replacements of knee and hip joints. American Journal of Preventative Medicine 2003; 25: 290-295.
12. Ackerman IN, Graves SE, Wicks IP, Bennell KL, Osborne RH. Severely compromised quality of life in women and those of lower socioeconomic status waiting for joint replacement surgery. Arthritis and Rheumatology 2005; 53: 653-658.
13. McGoey BV, Deitel M, Saplys RJF, Kliman ME. Effect of weight loss on musculoskeletal pain in the morbidly obese. Journal of Bone and Joint Surgery 1990; 72-B: 323-324.
14. Christensen R, Astrup A, Bliddal H. Weight loss: the treatment of choice for knee osteoarthritis? A randomized trial. Osteoarthritis and Cartilage 2005; 13: 20-27.
15. Tan D, Zwar NA, Dennis SM, Vagholkar S. Weight management in general practice: what do patients want? Medical Journal of Australia 2006; 185: 73-75.
16. Ammerman AS, DeVellis RF, Carey TS, Keyserling TC, Strogatz DS, Haines PS et al. Physician-based diet counseling for cholesterol reduction: current practices, determinants, and strategies for improvement. Preventative Medicine 1993; 22: 96-109.
17. Sanigorski AM, Bell AC, Kremer PJ, Swinburn BA. Lunchbox contents of Australian school children: room for improvement. European Journal of Clinical Nutrition 2005; 59: 1310-1316.
18. Summerbell CD, Waters E, Edmunds LD, Kelly S, Brown T, Campbell KJ. Interventions for preventing obesity in children. Cochrane Database of Systematic Reviews 2005, issue 3, art. no.: CD001871. DOI: 10.1002/14651858.CD001871.pub2.