Sophie Dell’Aniello

Concurrent use of tamoxifen with CYP2D6 inhibitors and the risk of breast cancer recurrence.

Concurrent use of tamoxifen and cytochrome P450 2D6 (CYP2D6) inhibitors, such as selective serotonin reuptake inhibitors, has been shown to decrease plasma concentrations of tamoxifen metabolites. However, it is still unclear whether such concurrent use affects tamoxifen’s effectiveness. Thus, the objective of this study is to determine whether concurrent use of tamoxifen with CYP2D6 inhibitors increases the risk of recurrence in patients newly diagnosed with breast cancer. We conducted a nested case–control analysis within a population-based cohort from the UK General Practice Research Database. The cohort included women with a first-ever diagnosis of breast cancer who were prescribed tamoxifen between January 1, 1998 and June 30, 2008. Cases consisted of all patients with a breast cancer recurrence occurring during follow-up. Up to ten controls were matched to each case on year of birth, date of cohort entry, and duration of follow-up. Conditional logistic regression was used to estimate rate ratios (RR) of breast cancer recurrence in patients who concurrently used tamoxifen with CYP2D6 inhibitors, compared to patients who only used tamoxifen. The cohort included 9,209 incident users of tamoxifen, of whom 807 were diagnosed with a breast cancer recurrence. Concurrent use was not associated with an increased incidence of breast cancer recurrence (adjusted RR 1.07, 95% 0.88, 1.30). Type and strength of CYP2D6 inhibitors, as well as duration of concurrent use did not affect breast cancer recurrence. These results remained consistent after performing sensitivity analyses. The results of this large population-based study indicate that concurrent use of tamoxifen with CYP2D6 inhibitors does not increase the risk of recurrence.

Association of Selective Serotonin Reuptake Inhibitors With the Risk for Spontaneous Intracranial Hemorrhage

Importance Selective serotonin reuptake inhibitors (SSRIs) may increase the risk for spontaneous intracranial hemorrhage (ICH), an effect that is in theory linked to the strength of inhibition of serotonin reuptake of an antidepressant. However, whether antidepressants that are strong inhibitors of serotonin reuptake actually increase the risk for ICH and the effect of concomitant use of antithrombotics are unknown. Objectives To assess the risk for ICH associated with the use of SSRIs compared with tricyclic antidepressants (TCAs) among new users of antidepressants and according to the relative affinity of the antidepressant for the serotonin transporter and to assess whether concomitant use of antithrombotics modifies this risk. Design, Setting, and Participants This population-based cohort study included new users of antidepressants 18 years or older from January 1, 1995, to June 30, 2014. More than 650 general practices in the United Kingdom contributing to the Clinical Practice Research Datalink enrolled patients. with use of a nested case-control approach, each case of a first ICH identified during follow-up was matched with as many as 30 control individuals by age, sex, calendar time, and duration of follow-up. Follow-up was completed on October 31, 2014. Interventions Current use of SSRIs compared with TCAs and strong compared with weak serotonin reuptake inhibitors. Main Outcomes and Measures Incidence rate ratios (RRs) of ICH. Results Among a cohort of 1 363 990 incident users of antidepressants (36.8% male; 63.2% female; mean [SD] age, 47.9 [18.5] years), 3036 cases of ICH were identified during follow-up and matched to 89 702 controls. Current SSRI use was associated with an increased risk for ICH (RR, 1.17; 95% CI, 1.02-1.35) relative to TCAs, highest during the first 30 days of use (RR, 1.44; 95% CI, 1.04-1.99), and translating in very few additional events. Similarly, the risk was increased by 25% with strong inhibitors (RR, 1.25; 95% CI, 1.01-1.54) and highest during the first 30 days of use (RR, 1.68; 95% CI, 0.90-3.12). Concomitant use of anticoagulants may increase the risk substantially (RR, 1.73; 95% CI, 0.89-3.39). Conclusions and Relevance The use of SSRIs and more generally of antidepressants with strong inhibition of serotonin reuptake are associated with an increased risk for ICH, particularly in the first 30 days of use and when used concomitantly with oral anticoagulants.

A net clinical benefit analysis of warfarin and aspirin on stroke in patients with atrial fibrillation: a nested case–control study

BackgroundAs the management of patients treated with anticoagulants and antiplatelet drugs entails balancing coagulation levels, we evaluated the net clinical benefit of warfarin and aspirin on stroke in a large cohort of patients with atrial fibrillation (AF).MethodsA population-based cohort study of all patients at least 18 years of age with a first-ever diagnosis of chronic AF during the period 1993–2008 was conducted within the United Kingdom General Practice Research Database. A nested case–control analysis was conducted to estimate the risk of ischemic stroke and intracranial hemorrhage associated with the use of warfarin and aspirin. Cases were matched up to 10 controls on age, sex, and date of cohort entry. The adjusted net clinical benefit of warfarin and aspirin (expressed as the number of strokes prevented per 100 persons per year) was calculated by subtracting the ischemic stroke rate (prevented by therapy) from the intracranial hemorrhage (ICH) rate (increased by therapy).ResultsThe cohort included 70,766 patients newly-diagnosed with chronic AF, of whom 5519 experienced an ischemic stroke and 689 an ICH during follow-up. The adjusted net clinical benefit of warfarin was 0.59 (95% CI: 0.45, 0.73). However, the benefit was not seen for patients below (0.08, 95%: -0.38, 0.54) and above (−0.49, 95% CI: -1.13, 0.15) therapeutic range. The net clinical benefit of warfarin, apparent after 3 months of continuous use, increased as a function of CHADS2 score. The net clinical benefit was not significant with aspirin (−0.07, 95% CI: -0.22, 0.08), though it was seen in certain subgroups.ConclusionsWarfarin provides a net clinical benefit in patients with atrial fibrillation, which is maintained with longer duration of use, particularly when used within therapeutic range. A similar net effect is not as clear with aspirin.

Concurrent use of statins and hormone therapy and risk of venous thromboembolism in postmenopausal women: a population-based case-control study.

ObjectiveStatins and hormone therapy (HT), often used concurrently in postmenopausal women, have antagonist effects on the risk of venous thromboembolism (VTE). This study aims to determine whether statins attenuate the increased VTE risk associated with HT. MethodsWe conducted a nested case-control study within a population-based cohort of women aged 50 to 79 years between January 1, 1987 and March 1, 2008, who were identified from the UK General Practice Research Database. Cases of VTE occurring during follow-up were identified and each matched with up to 10 controls from the cohort. Odds ratios (ORs) for the effects of concurrent HT and statin use on the risk of VTE were estimated using conditional logistic regression with interaction terms. ResultsThe cohort included 955,582 postmenopausal women, with 23,505 cases of VTE matched with 231,562 controls. Regardless of any HT use, current use of statins was associated with a decreased risk of VTE (OR, 0.83; 95% CI, 0.78-0.87). The interaction between statin use and HT use was of borderline significance (P = 0.053). Consequently, among nonusers of statins, the risk of VTE was elevated with current use of oral estrogen and progestogen combinations (OR, 1.55; 95% CI, 1.45-1.66) but this risk was not elevated among users of statins (OR, 0.98; 95% CI, 0.56-1.73). There was no such modification of the OR with statins and other HT types and formulations. ConclusionsStatins could potentially attenuate the increased risk associated with HT combinations of oral estrogens and progestogens. This observation needs further confirmation in other large cohorts.

Sulfonylureas as second line drugs in type 2 diabetes and the risk of cardiovascular and hypoglycaemic events: population based cohort study

Abstract Objective To assess whether adding or switching to sulfonylureas is associated with an increased risk of myocardial infarction, ischaemic stroke, cardiovascular death, all cause mortality, and severe hypoglycaemia, compared with remaining on metformin monotherapy in patients with type 2 diabetes. Design Population based cohort study. Setting General practices contributing data to the UK Clinical Practice Research Datalink. Participants Patients with type 2 diabetes initiating metformin monotherapy between 1998 and 2013. Main outcome measures Using the prevalent new-user cohort design we matched 1:1 patients adding or switching to sulfonylureas with those remaining on metformin monotherapy on high-dimensional propensity score, haemoglobin A1c, and number of previous metformin prescriptions. The two groups were compared using Cox proportional hazards models to estimate adjusted hazard ratios and 95% confidence intervals for the study outcomes. Results Among 77 138 metformin initiators, 25 699 added or switched to sulfonylureas during the study period. During a mean follow-up of 1.1 years, sulfonylureas were associated with an increased risk of myocardial infarction (incidence rate 7.8 v 6.2 per 1000 person years, hazard ratio 1.26, 95% confidence interval 1.01 to 1.56), all cause mortality (27.3 v 21.5, 1.28, 1.15 to 1.44), and severe hypoglycaemia (5.5 v 0.7, 7.60, 4.64 to 12.44) compared with continuing metformin monotherapy. There was a trend towards increased risks of ischaemic stroke (6.7 v 5.5, 1.24, 0.99 to 1.56) and cardiovascular death (9.4 v 8.1, 1.18, 0.98 to 1.43). Compared with adding sulfonylureas, switching to sulfonylureas was associated with an increased risk of myocardial infarction (hazard ratio 1.51, 95% confidence interval, 1.03 to 2.24) and all-cause mortality (1.23, 1.00 to 1.50). No differences were observed for ischaemic stroke, cardiovascular death, or severe hypoglycaemia. Conclusions Sulfonylureas as second line drugs are associated with an increased risk of myocardial infarction, all cause mortality, and severe hypoglycaemia, compared with remaining on metformin monotherapy. Continuing metformin when introducing sulfonylureas appears to be safer than switching.

The Use of Telmisartan and the Incidence of Cancer.

BACKGROUND A meta-analysis reported an 8% increased risk of cancer with the use of angiotensin receptor blockers (ARBs), but subsequent meta-analyses and observational studies did not confirm this risk. However, telmisartan comprised 85% of the data in the original meta-analysis. Thus, the objective of this study was to determine whether the use of telmisartan, compared with other ARBs, is associated with an increased risk of cancer. METHODS We used the United Kingdom Clinical Practice Research Datalink to assemble a cohort of all patients newly treated with ARBs between 2000 and 2008, and followed until December 2010. Time-dependent cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of cancer associated with telmisartan, compared with other ARBs, adjusted for potential confounders. Secondary analyses assessed the risk with each of the 4 most common cancers (lung, breast, prostate, colorectal). RESULTS The cohort consisted of 62,109 new ARB users, which included 3,438 telmisartan and 58,671 other ARB users. Compared with other ARBs, telmisartan use was not associated with an increased risk of cancer overall (16.3 vs. 15.0 per 1,000 person-years, respectively; adjusted HR: 0.93, 95% CI: 0.81-1.06) or by cancer site (lung, HR: 0.91, 95% CI: 0.55-1.51; breast, HR: 1.28, 95% CI: 0.90-1.82; prostate, HR: 0.79, 95% CI: 0.53-1.18; colorectal, HR: 1.41, 95% CI 0.95-2.10). CONCLUSIONS Compared with other ARBs, telmisartan is not associated with an increased risk of cancer. This study provides reassurance as to the short-term safety of telmisartan.

Comparative effectiveness of novel oral anticoagulants in UK patients with non-valvular atrial fibrillation and chronic kidney disease: a matched cohort study

Objectives To evaluate the effectiveness and safety of novel oral anticoagulants (NOACs) compared with vitamin K antagonists (VKAs) among patients with non-valvular atrial fibrillation (NVAF), particularly those with chronic kidney disease (CKD). Design Population-based matched cohort study. Setting Over 670 primary care practices in the UK, contributing to the Clinical Practice Research Datalink. Participants Up to 6818 adult patients newly treated with NOACs between 2011 and 2016, matched 1:1 to new users of VKAs on age, sex and high-dimensional propensity score. Interventions Current exposure to NOACs compared with current exposure to VKAs. Main outcome measures HRs of ischaemic stroke and systemic embolism (SE), major bleeding, gastrointestinal (GI) bleeding, intracranial bleeding, myocardial infarction and all-cause mortality. Results In as-treated analyses, the rates of ischaemic stroke/SE were similar between NOACs and VKAs (HR 0.94; 95% CI 0.62 to 1.42), as were the rates of major bleeding (HR 0.86; 95% CI 0.56 to 1.33). NOACs also significantly increased the risk of GI bleeding (HR 1.78; 95% CI 1.27 to 2.48). In patients with NVAF and CKD, NOACs and VKAs remained comparable with respect to the risk of ischaemic stroke/SE (HR 0.79; 95% CI 0.40 to 1.58) and major bleeding (HR 0.88; 95% CI 0.47 to 1.62), with no difference in the risk of GI bleeding (HR 0.99; 95% CI 0.63 to 1.55). Similar results were obtained in on-treatment analyses using a time-dependent exposure definition. Conclusions Our results suggest that in the UK primary care, NOACs are overall effective and safe alternatives to VKAs, among patients with NVAF altogether, as well as in patients with NVAF and CKD.