Changes in the levels of major cardiovascular risk factors in the multi-ethnic population in Singapore after 12 years of a national non-communicable disease intervention programme.

INTRODUCTION

The National Healthy Lifestyle Programme, a population-wide non-communicable disease intervention programme, was started in 1992. A National Health Survey is carried out every six years to evaluate the impact of this programme on the cardiovascular risk factor profile of the resident population of Singapore.

METHODS

The 2004 National Health Survey (NHS 04) was a population-based survey carried out over a period of four months from September to December 2004. A combination of disproportionate stratified sampling and systematic sampling was used to select a representative sample (n=7,078) for the survey. The reference population comprised 2.4 million multi-racial Singaporeans aged 18-69 years. Anthropometric and blood pressure measurements were carried out on all subjects and blood samples were taken for biochemical analysis. The results were compared with those of a similar survey conducted in 1998.

RESULTS

A total of 4,084 Singapore residents took part in the survey, giving a response rate of 57.7 percent. The age-standardised prevalence of hypertension (greater than or equal to 140/90 mmHg) in Singapore residents aged 30-69 years decreased from 28.0 percent in 1998 to 24.0 percent (p-value is less than 0.001) in 2004. The prevalence of high total cholesterol (greater than or equal to 6.2 mmol/L) among those aged 18-69 years fell from 26.0 percent in 1998 to 18.1 percent (p-value is less than 0.001) in 2004. The prevalence of diabetes mellitus in residents aged 18-69 years in 2004 was 7.8 percent, compared to the 1998 level of 9.5 percent (p-value is less than 0.01). The level of obesity (body mass index is greater than or equal to 30 kg/sqm) increased slightly from 6.2 percent in 1998 to 6.8 percent (p-value equals 0.1627). The prevalence of daily smoking decreased from 15.0 percent in 1998 to 12.5 percent in 2004 (p-value is less than 0.001), while that of regular exercise increased from 17.0 percent to 25.0 percent (p-value is less than 0.001). Ethnic differences in the prevalence of diabetes mellitus, hypertension, hypercholesterolaemia, and exercise were observed.

CONCLUSION

The NHS 04 results suggest that the National Healthy Lifestyle Programme significantly decreased daily smoking, high blood cholesterol and hypertension, and increased regular exercise over 1998 levels. The results also suggest that the programme stabilised the prevalence of obesity and diabetes mellitus.