Prevalence of High Cholesterol levels, hypertension and Smoking, particularly among overweight and obese adults, have declined considerably over the past 40 years, according to new research.

This trend was not true for Diabetes, which has had a stable prevalence.

Researchers from the Centers for Disease Control and Prevention, Atlanta, analysed data from five National Health and Nutrition Examination Surveys (NHANES) conducted during the last 40 years and examined whether long-term changes in levels of key cardiovascular risk factors have been different in overweight or obese persons compared with lean persons.

The risk factors included prevalence of High cholesterol levels, high blood pressure, current smoking, and total diabetes (diagnosed and undiagnosed combined) according to BMI group (lean, less than 25; overweight, 25-29; and obese, 30 or greater).

A substantial decline in the prevalence of key CVD risk factors over the last three to four decades, affecting obese, overweight, and lean segments of the population, was found, with diabetes a notable exception to the observed reduction in risk factors.

Prevalence of total diabetes (ie, diagnosed and undiagnosed combined) did not decrease within BMI groups. This was accompanied by a 55% increase in total diabetes among the overall population (ie, all BMI groups combined), presumably due to an increasing proportion of the population moving into the obese categories, the authors write.

A cholesterol molecule: prevalence of High cholesterol levels have fallen over the past 40 years

Despite their encouraging findings, a considerable proportion of lean as well as obese persons still have elevated levels of modifiable risk factors, they say. Clinical and public health efforts should continue to emphasise maintenance of healthy lifestyle behaviours for both lean as well as overweight and obese persons, they conclude. (Gregg EW et al. Secular trends in cardiovascular disease risk factors according to Body Mass Index in US adults. JAMA 2005; 293: 1868-1874).

Copyright TG Scott & Son Ltd. Jun 2005

Source: Community Practitioner