Population-Based 5-Year Follow-Up Study in Taiwan of Dementia and Risk of Stroke

Abstract

BackgroundThis study estimates the risk of stroke within 5 years of newly diagnosed dementia among elderly persons aged 65 and above. We examined the relationship between antipsychotic usage and development of stroke in patients with dementia.MethodsWe conducted a nationwide 5-year population-based study using data retrieved from the Longitudinal Health Insurance Database 2005 (LHID2005) in Taiwan. The study cohort comprised 2243 patients with dementia aged ≥65 years who had at least one inpatient service claim or at least 2 ambulatory care claims, whereas the comparison cohort consisted of 6714 randomly selected subjects (3 for every dementia patient) and were matched with the study group according to sex, age, and index year. We further classified dementia patients into 2 groups based on their history of antipsychotic usage. A total of 1450 patients were classified into the antipsychotic usage group and the remaining 793 patients were classified into the non-antipsychotic usage group. Cox proportional-hazards regressions were performed to compute the 5-year stroke-free survival rates after adjusting for potentially confounding factors.ResultsThe dementia patients have a 2-fold greater risk of developing stroke within 5 years of diagnosis compared to non-dementia age- and sex-matched subjects, after adjusting for other risk factors (95% confidence interval (CI) = 2.58–3.08; P<.001). Antipsychotic usage among patients with dementia increases risk of stroke 1.17-fold compared to patients without antipsychotic treatment (95% CI = 1.01–1.40; P<.05).ConclusionsDementia may be an independent risk factor for stroke, and the use of antipsychotics may further increase the risk of stroke in dementia patients.

Antipsychotics and the Risk of Cerebrovascular Accident: A Systematic Review and Meta-Analysis of Observational Studies

“…16,37,38,42 The heterogeneity in the observed risk of CVA can be partly attributed to differences in study design. For study design, 5 studies were case-control, 16,19,36e38 1 casecase-time-control study, 40 1 self-control case series study, 41 1 crosssectional study, 25 and 2 cohort studies. 39,42 Heterogeneity in CVA risk may also be attributed to differences in patient selection as demonstrated in Table 1.…”

“…39,42 Heterogeneity in CVA risk may also be attributed to differences in patient selection as demonstrated in Table 1. Five studies evaluated elderly dementia patients, 16,19,38,41,42 1 study evaluated schizophrenia patients, 37 and 6 studies evaluated general or hospitalized elderly patients. 25,36e40 Use of SGAs in patients without dementia resulted in an increased risk of CVA (OR 1.69, 95% CI 0.79e3.63), but the results remained nonsignificant and heterogeneous.…”

“…Finally, 10 articles met the inclusion criteria and were included in the meta-analysis. These 10 studies 16,19,25,36e42 included 16,993 CVA cases from 5 case-control studies, 16,19,36e38 1 case-case-time-control, 40 1 self-control case series study, 41 1 cross-sectional study, 25 and 2 cohort studies. 39 databases, 16,19,36e42 whereas 1 study used an electronic health record (Table 1).…”

“…25 All studies included adult participants, 8 of which focused on elderly patients, 16,19,36e39,41,42 and 5 of which included patients with dementia. 16,19,38,41,42 Characteristics of individual studies are summarized in Table 1.…”

“…Restricting the analysis to only population-based studies, use of any antipsychotics was still associated with an increased CVA risk (OR 1.51; 95% CI 1.20e1.91; I 2 ¼ 93.3%). 16,19,25,36,37,40 Seven studies investigated the use of any antipsychotics in the elderly population, and a similar increase in CVA risk was observed (OR 1.49; 95% CI 1.25e1.77; 16,19,36e38,41,42 However, only 4 studies evaluated the use of any antipsychotics in dementia patients and the results showed a low risk of CVA (OR 1.17; 95% CI 1.08e1.26; I 2 ¼ 0%). 16,19,38,42 Five studies used case-control design and the remaining studies used other designs.…”