February 3rd, 2011
Lancet Papers Outline Worldwide Trends in Obesity, Hypertension, and Cholesterol
Larry Husten, PHD
Three papers published in the Lancet provide the most detailed view yet of worldwide trends over the last 3 decades in body-mass index (BMI), blood pressure, and cholesterol, and also include numerous details about different regions and countries. Here are a few highlights of the reports from the Global Burden of Metabolic Risk Factors of Chronic Diseases Collaborating Group:
BMI:
- Worldwide, since 1980, mean BMI increased by 0.4 kg/m2 per decade for men and 0.5 kg/m2 per decade for women.
- More than half a billion people in the world are now obese.
- For both men and women, BMIs were highest in some Oceania countries.
- Among high-income countries, the U.S. had the highest mean BMI.
Cholesterol:
- Worldwide, in 2008, mean total cholesterol was 4.64 mmol/L for men and 4.76 mmol/L for women, nearly the same as it was in 1980.
- In high-income countries, total cholesterol fell since 1980, but remained highest when compared with other countries.
- Total cholesterol increased in east and southeast Asia and Pacific.
- The lowest cholesterol levels were found in sub-Saharan Africa.
Blood pressure:
- Worldwide, in 2008, mean systolic blood pressure (SBP) was 128.1 mm Hg in men and 124.4 mm Hg in women.
- Since 1980, global SBP decreased by 0.8 mm Hg per decade in men and 1.0 mm Hg per decade in women.
- For women, SBP declined the most in Western Europe and Australasia.
- For men, SBP fell the most in high-income North America.
- For both men and women, SBP rose in Oceania, east Africa, and south and southeast Asia.
- For women, SBP was highest in east and west African countries.
- For men, SBP was highest in Baltic and east and west African countries.
In an accompanying comment, Sonia Anand and Salim Yusuf write that “the forecast for cardiovascular disease burden in low-income and middle-income countries over the next few decades is dismal and comprises a population emergency that will cost tens of millions of preventable deaths, unless rapid and widespread actions are taken by governments and health-care systems worldwide.”
Although it is an ideal partner to medical and surgical therapies, population-based cardiovascular risk reduction is a hard sell. The number of books, talk shows, infomercials, magazine articles on weight, exercise, lipids, hypertension, and diabetes skyrocket in inverse proportion to the effort people are willing to exert themselves. Yet fewer than 10% of patients attending a CV risk reduction program are willing to keep a diet diary for 4 days. Lots of talk, little walk.
The message that medical and surgical care is limitless and provides instant complete cure without any patient responsibility or participation (or payment)is not only incorrect but undermines motivation for primordial prevention. Many believe that PCI or CABG is a “cure”, and hence the atherogenicity of diets one year following CABG actually increases, during which time statin adherence also drops precipitously.
The point is that no matter how we refine risk prediction, the epidemiology of CV events precludes perfect identification of high-risk patients. And even if it were possible, residual risk is so significant, even with “perfect” therapy, events will continue. Primordial prevention is going to be absolutely necessary to prevent the tsunami of CVD predicted in the Lancet.
Interpretations given to the recent CDC report that diabetes and obesity are rising even faster than last tallied: supply more medical care to everyone! The better approach is that with sensible diets and some movement, rather than all that pizza and fried chicken sitting in front of a screen for hours, more people won’t need their unlimited “free” medical care.
We have also reached a point where there are so many “interested parties” in our present obesogenic environment that changing fundamentals for the better is virtually impossible. Hence, the food industry, restaurateurs, government agencies, etc. will continue to supply and promote unhealthy food and lifestyles, and the public will continue to behave accordingly.
Re the editorial by Anand and Yusuf-I agree it is strange that BP and lipids did not follow BMI, especially at a time and in countries where BP meds and statin prescriptions were not increasing.
Of interest: review by Fuster http://www.amjmed.com/article/S0002-9343(10)00836-3/fulltext and http://tak.sagepub.com/content/early/2010/12/21/1753944710391350.abstract
Richard Kones MD
The more equivalent the diets and the activities of world population will become, the more equal will be the incidence of ,at least, certain illnesses like the SBP.Indeed diets and daily habits are nore and more similar. Franco