Jousilahti P, Vartiainen E, Tuomilehto J, Puska P
National Public Health Institute, Helsinki, Finland.
Ann Intern Med. 1996 Nov 1;125(9):713-22. doi: 10.7326/0003-4819-125-9-199611010-00002.
In cross-sectional analyses, serum cholesterol levels differ among different age groups. However, secular time trends in cholesterol levels can be seen across age groups in a population. A birth cohort analysis provides useful information on the combined effect of age and time on changes in serum cholesterol levels.
To analyze the 20-year dynamics of serum total cholesterol levels in relation to age, sex, birth cohort, time period, mortality rate, and changes in the intake of saturated fats.
Cross-sectional measurements of serum total cholesterol levels in five independent population surveys done in 1972, 1977, 1982, 1987, and 1992.
Kuopio and North Karelia provinces in eastern Finland.
Random sample of 16,711 men and 17,542 women 25 to 64 years of age. Persons in the oldest birth cohort were born in 1913; persons in the youngest birth cohort were born in 1967.
Total serum cholesterol levels and daily intake of dietary fat.
Between 1972 and 1992, mean cholesterol levels decreased with time in each age group and for both sexes. According to the cross-sectional data, cholesterol levels increased with age and increased more steeply in women than in men. Contrary to these data, cholesterol levels in birth cohorts did not increase with age. Cholesterol levels did not change at all within birth cohorts of women and started to decrease after 45 years of age in birth cohorts of men. Cholesterol levels in the youngest birth cohorts (persons 25 to 29 years of age) entering the study each study year were markedly lower than levels in the same age group in the previous survey of risk factors. Daily intake of saturated fat decreased markedly between 1972 and 1992. Most of this decrease could be explained by change in intake of liquid dairy products and spreadable fats. In both sexes, changes in saturated fat intake were correlated with the time period, whereas the association with age was weak.
In this Finnish population, total serum cholesterol levels are more closely associated with birth cohort than with age. Changes in dietary intake of saturated fat over time may account for changes in cholesterol levels. This finding suggests that community-based strategies for preventing cardiovascular disease can affect most of the population.
在横断面分析中，不同年龄组的血清胆固醇水平存在差异。然而，在一个人群中，各年龄组的胆固醇水平都存在长期的时间趋势。出生队列分析为年龄和时间对血清胆固醇水平变化的综合影响提供了有用信息。
分析血清总胆固醇水平在20年中的变化动态，以及与年龄、性别、出生队列、时间段、死亡率和饱和脂肪摄入量变化的关系。
在1972年、1977年、1982年、1987年和1992年进行的五项独立人群调查中对血清总胆固醇水平进行横断面测量。
芬兰东部的库奥皮奥省和北卡累利阿省。
年龄在25至64岁之间的16,711名男性和17,542名女性的随机样本。最年长出生队列中的人出生于1913年；最年轻出生队列中的人出生于1967年。
血清总胆固醇水平和膳食脂肪的每日摄入量。
1972年至1992年间，各年龄组及男女两性的平均胆固醇水平均随时间下降。根据横断面数据，胆固醇水平随年龄增长而升高，且女性升高幅度比男性更大。与这些数据相反，出生队列中的胆固醇水平并未随年龄增长。女性出生队列中的胆固醇水平根本没有变化，男性出生队列中的胆固醇水平在45岁后开始下降。每年进入研究的最年轻出生队列（25至29岁的人）的胆固醇水平明显低于上一次危险因素调查中同一年龄组的水平。1972年至1992年间，饱和脂肪的每日摄入量显著下降。这种下降大部分可归因于液态乳制品和可涂抹脂肪摄入量的变化。在男女两性中，饱和脂肪摄入量的变化与时间段相关，而与年龄的关联较弱。
在这个芬兰人群中，血清总胆固醇水平与出生队列的关联比与年龄的关联更紧密。随着时间推移，膳食中饱和脂肪摄入量的变化可能是胆固醇水平变化的原因。这一发现表明，基于社区的心血管疾病预防策略可以影响大多数人群。
