Importance: Although hormone therapy (HT) in perimenopausal women is associated with increased risk for venous thromboembolism (VTE), it is unclear to what extent statins may mitigate this HT-associated risk.
Objective: To estimate VTE risk in women aged 50 to 64 years taking HT with or without statins.
Design, setting, and participants: This nested case-control study analyzed data from a commercially insured claims database in the US. Eligible participants included women aged 50 to 64 years with at least 1 year of continuous enrollment between 2008 and 2019. Data analysis occurred from January 2022 to August 2023.
Exposure: Filled prescriptions for estrogens, progestogens, and statins were recorded in the 12 months prior to index. Recent HT was defined as any estrogen or progestogen exposure within 60 days before the index date. Current statin exposure was defined as 90 or more days of continuous exposure prior to and including the index date. Statin intensity was defined by the statin exposure 30 days prior to index.
Main outcomes and measures: Cases were identified with VTE diagnoses (diagnostic codes) preceded by at least 12 months without VTE and followed within 30 days by anticoagulation, an inferior vena cava filter placement, or death. Controls were matched to cases (10:1) on date and age. Conditional logistic regression models estimated risk for HT and statin exposures with odds ratios (OR), adjusted for comorbidities. Conditional logistic regression models were used to estimate VTE risk for HT and statin exposures with odds ratios (ORs), adjusted for comorbidities. Intensity of statin therapy was measured as a subgroup analysis.
Results: The total sample of 223 949 individuals (mean [SD] age, 57.5 [4.4] years) included 20 359 cases and 203 590 matched controls. Of the entire sample, 19 558 individuals (8.73%) had recent HT exposure and 36 238 individuals (16.18%) had current statin exposure. In adjusted models, individuals with any recent HT exposure had greater odds of VTE compared with those with no recent HT exposure (OR, 1.51; 95% CI, 1.43-1.60). Individuals receiving current statin therapy had lower odds of VTE compared with those with no current statin exposure (OR, 0.88; 95% CI, 0.84-0.93). When compared with those not recently taking HT or statins, the odds of VTE were greater for those taking HT without statins (OR, 1.53; 95% CI, 1.44-1.63) and for those taking HT with statins (OR, 1.25; 95% CI, 1.10-1.43), but were lower for those taking statins without HT (OR, 0.89; 95% CI, 0.85-0.94). Individuals taking HT with statin therapy had 18% lower odds of VTE than those taking HT without statins (OR, 0.82; 95% CI, 0.71-0.94) and there was greater risk reduction with higher intensity statins.
Conclusions and relevance: In this case-control study, statin therapy was associated with reduced risk of VTE in women taking HT, with greater risk reduction with high-intensity statins. These findings suggest that statins may reduce risk of VTE in women exposed to HT and that HT may not be contraindicated in women taking statins.