Department of Epidemiology, Erasmus MC University Medical Center, Rotterdam, The Netherlands.
Neurology. 2012 May 8;78(19):1456-63. doi: 10.1212/WNL.0b013e3182553be6. Epub 2012 May 2.
To investigate whether dementia incidence has changed over the last 2 decades.
We compared dementia incidence in 2 independent subcohorts of persons aged 60-90 years from the Rotterdam Study, a population-based cohort study. The first subcohort started in 1990 (n = 5,727), the second in 2000 (n = 1,769). Participants were dementia-free at baseline and followed for at maximum 5 years. We calculated age-adjusted dementia incidence rates for the 2 subcohorts in total, in 10-year age strata, and for men and women separately. We also compared mortality rates, differences in prevalence of vascular risk factors, and medication use. Finally, we compared brain volumes and the extent of cerebral small vessel disease in participants who underwent brain imaging 5 years after the baseline examinations.
In the 1990 subcohort (25,696 person-years), 286 persons developed dementia, and in the 2000 subcohort (8,384 person-years), 49 persons. Age-adjusted dementia incidence rates were consistently, yet nonsignificantly, lower in the 2000 subcohort in all strata, reaching borderline significance in the overall analysis (incidence rate ratio 0.75, 95% confidence interval [CI] 0.56-1.02). Mortality rates were also lower in the 2000 subcohort (rate ratio 0.63, 95% CI 0.52-0.77). The prevalence of hypertension and obesity significantly increased between 1990 and 2000. This was paralleled by a strong increase in use of antithrombotics and lipid-lowering drugs. Participants in 2005-2006 had larger total brain volumes (p < 0.001) and less cerebral small vessel disease (although nonsignificant in men) than participants in 1995-1996.
Although the differences in dementia incidence were nonsignificant, our study suggests that dementia incidence has decreased between 1990 and 2005.
研究过去 20 年痴呆发病率是否发生了变化。
我们比较了来自鹿特丹研究的两个独立的 60-90 岁人群亚队列的痴呆发病率，这是一项基于人群的队列研究。第一个亚队列于 1990 年开始（n=5727），第二个亚队列于 2000 年开始（n=1769）。参与者在基线时无痴呆，随访时间最长为 5 年。我们计算了两个亚队列的总年龄调整后痴呆发病率、10 年年龄分层发病率以及男女单独发病率。我们还比较了死亡率、血管危险因素患病率和药物使用的差异。最后，我们比较了在基线检查后 5 年接受脑部成像的参与者的脑容量和脑小血管疾病的严重程度。
在 1990 年的亚队列（25696 人年）中，有 286 人发生痴呆，而在 2000 年的亚队列（8384 人年）中，有 49 人发生痴呆。在所有分层中，2000 年亚队列的年龄调整后痴呆发病率始终且不显著地较低，在总体分析中达到边缘显著（发病率比 0.75，95%置信区间[CI] 0.56-1.02）。2000 年亚队列的死亡率也较低（比率 0.63，95%CI 0.52-0.77）。1990 年至 2000 年期间，高血压和肥胖的患病率显著增加。与此同时，抗血栓药物和降脂药物的使用也大幅增加。2005-2006 年的参与者的总脑容量较大（p<0.001），脑小血管疾病较少（尽管在男性中无统计学意义），而 1995-1996 年的参与者则较少。
尽管痴呆发病率的差异无统计学意义，但我们的研究表明，1990 年至 2005 年间痴呆发病率有所下降。
