Objectives

Pre-existing cognitive decline is a risk factor for stroke onset and poststroke dementia. There is a knowledge gap on prestroke cognitive decline in indigenous Africans. We estimated prevalence and predictors of prestroke cognitive decline, as well as its association with poststroke dementia at one year in Nigerian survivors of a first ever stroke.

Methods

Prospective observational study. Prestroke cognitive decline was ascertained using an average score > 3.31 on the 16-item Informant Questionnaire for Cognitive Decline in the Elderly (IQ-CODE). Poststroke dementia was ascertained according to the ‘National Institute of Neurological Disorders and Stroke and the Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) criteria’. Associations were investigated using multivariate logistic regression models and presented as odds ratios (O.R) within 95% confidence intervals (C.I).

Results

Among 150 stroke survivors, prestroke cognitive decline was found in 25 (16.7%, 95% C.I = 11.5%–23.6%). In analyses adjusting for the effect of age, education and stroke severity, prestroke cognitive decline was associated with diabetes mellitus (O.R = 3.0, 95% C.I = 1.2–7.6). Ten (62.5%) survivors in the prestroke cognitive decline sub-sample developed dementia at one-year poststroke. In analyses adjusting for the effects of age, education, stroke severity and comorbid diabetes mellitus, survivors with prestroke cognitive decline had six times the odds of dementia at one year poststroke (O.R = 6.2, 95% C.I = 1.3–30.4).

Conclusion

Prestroke cognitive decline is common, assessment is feasible and identifying pre-stroke problems has prognostic implications.

中文翻译：

---

非洲人卒中前认知能力下降：患病率、预测因素和与卒中后痴呆的关联

目标

预先存在的认知能力下降是中风发作和中风后痴呆的危险因素。在土著非洲人中风前认知能力下降方面存在知识差距。我们估计了尼日利亚首次中风幸存者中卒中前认知能力下降的患病率和预测因素，以及其与卒中后痴呆症的相关性。

方法

前瞻性观察研究。使用 16 项老年人认知衰退知情人问卷 (IQ-CODE) 的平均得分 > 3.31 来确定卒中前认知衰退。根据“国家神经疾病和中风研究所和国际研究协会和神经科学学会 (NINDS-AIREN) 标准”确定中风后痴呆。使用多变量逻辑回归模型研究关联，并以 95% 置信区间 (CI) 内的优势比 (OR) 表示。

结果

在 150 名中风幸存者中，有 25 人发现中风前认知能力下降（16.7%、95% C. I  = 11.5%–23.6%）。在调整年龄、教育程度和中风严重程度影响的分析中，中风前认知能力下降与糖尿病相关（O. R  = 3.0，95  % C. I = 1.2–7.6）。中风前认知衰退子样本中的 10 名 (62.5%) 幸存者在中风后一年发展为痴呆症。在调整年龄、教育、中风严重程度和合并糖尿病的影响的分析中，中风前认知能力下降的幸存者在中风后一年患痴呆症的几率是其六倍（O. R  = 6.2, 95% C. I  = 1.3–30.4 ）。

结论

中风前认知下降很常见，评估是可行的，识别中风前问题具有预后意义。