Summary
Despite continued uncertainty of venous thromboembolism (VTE) caused from antipsychotic
agents, this safety issue has not been examined in postmenopausal women, a population
with high usages of antipsychotics and at high risk for VTE. We assessed whether antipsychotic
use was associated with an increased VTE risk in women after menopause. We conducted
a nested case-control study of all Taiwanese women aged ≥ 50 years (n = 316,132) using
a nationwide healthcare claims database between 2000 and 2011. All newly diagnosed
VTE patients treated with an anticoagulant or thrombectomy surgery were identified
as cases (n = 2,520) and individually matched to select controls (n = 24,223) by cohort
entry date, age, cancer diagnosis and major surgery procedure. The odds ratios (ORs)
and 95 % confidence interval (CI) of VTE associated with antipsychotics were estimated
by multivariate conditional logistic regressions. Current use of antipsychotics was
associated with a 1.90-fold (95 % CI = 1.64–2.19) increased VTE risk compared with
nonuse in postmenopausal women. The VTE risk existed in a dose-dependent fashion (test
for trend, p<0.001), with a more than quadrupled risk for high-dose antipsychotics
(adjusted OR = 4.60; 95 % CI = 2.88–7.33). Current parenteral administration of antipsychotics
also led to a 3.46-fold increased risk (95 % CI = 2.39–5.00). Conversely, there was
no increased VTE risk when antipsychotics were discontinued for > 30 days. In conclusion,
current use of antipsychotics is significantly associated with a dose-dependent increased
risk of VTE in postmenopausal women, especially for those currently taking high-dose
or receiving parenteral antipsychotics.
Keywords
Venous thromboembolism (VTE) - nested case-control - antipsychotics - postmenopause
- epidemiology
