Greater decreases in cholesterol levels among individuals with high cardiovascular risk than among the general population: the northern Sweden MONICA study 1994 to 2014

Aim: Decreasing cholesterol levels in Western populations is the main reason for decreasing mortality due to coronary heart disease. Our aim was to analyze trends in cholesterol levels in the population during a period of 20 years in relation to previous cardiovascular disease (CVD), other cardiovascular risk factors, and socioeconomic status.

Methods and results: A total of 4546 women and 4349 men aged 25-74 years participated in five population-based surveys in the Northern Sweden MONICA Study between 1994 and 2014 (participation rate 76.8-62.5%). Total cholesterol levels decreased from 6.2 mmol/L (95% confidence interval, CI, 6.1-6.2) in 1994 to 5.5 mmol/L (CI 5.4-5.5) in 2014. The decrease was more pronounced in elderly vs. younger participants (1.0 vs. 0.5 mmol/L). In 2014, participants with previous CVD, diabetes, or hypertension had lower cholesterol levels than the general population, whereas their levels were higher or similar to the general population in 1994. The use of lipid-lowering drugs increased markedly and was used by 14.3% in 2014. Previously described differences in cholesterol levels between participants with obesity and normal weight, and between those with and without university education, diminished, or vanished over time.

Conclusion: Cholesterol levels decreased by 0.7 mmol/L over 20 years with no sign of abating. The improvement occurred in all age and gender groups but more prominently among those at high risk of ischaemic heart disease.