Nationwide Case-crossover Study Research Articles

Use of antidepressants and risk of hospitalization for acute myocardial infarction: A nationwide case-crossover study

BackgroundWe aimed to investigate the association between antidepressant use and the risk of hospitalization for acute myocardial infarction (AMI). MethodsA case-crossover study was conducted using a nationwide population-based sample from Taiwan's National Health Insurance Research Database. A total of 18,631 patients with incident AMI were included in this study. The effects of antidepressant use as well as that of various classes (including tricyclic or tetracyclic antidepressants; selective serotonin reuptake inhibitors; or serotonin norepinephrine reuptake inhibitors), doses, and receptor-binding profiles of the antidepressants on AMI were assessed. Conditional logistic regression models with adjustment for potential confounding factors were applied to determine the effects of antidepressant use on the risk of AMI during case and control time periods of 15, 30, and 60 days, respectively. The modifiable effects of age, gender, and comorbidity were evaluated by stratified analysis. ResultsAntidepressant use was not associated with the risk of AMI (adjusted odds ratio [AOR] = 1.04; 95% confidence interval (CI): 0.88–1.24). Likewise, neither the class, dose, nor the binding affinity of serotonin transporter or norepinephrine transporter was associated with AMI risks, and there was no modifying effect of age, gender, or comorbid medical condition on the association between antidepressant use and AMI. ConclusionsUse of antidepressant drugs was not associated with the risk of AMI.

Acute Respiratory Infection and Use of Nonsteroidal Anti-Inflammatory Drugs on Risk of Acute Myocardial Infarction: A Nationwide Case-Crossover Study.

Previous studies have suggested that acute respiratory infection (ARI) and nonsteroidal anti-inflammatory drugs (NSAIDs) use could trigger acute myocardial infarction (AMI). In some countries, physicians prescribe NSAIDs for patients with ARI for symptom relief. However, there is no research evaluating whether NSAIDs use during ARI episodes may increase the risk of AMI. We identified 9793 patients with an incident hospitalization of AMI (index date) between 2007 and 2011. Using case-crossover design, we compared the following exposure status between the case (1-7-day before index date) and matched control period (366-372-day before index date): NSAIDs use during ARI episodes, ARI episodes without NSAIDs use, NSAIDs use only, or no exposure. Multivariable conditional logistic regression models were used to estimate odds ratios adjusted for potential confounders. Nonsteroidal anti-inflammatory drugs use during ARI was associated with a 3.4-fold increased risk of AMI (adjusted odds ratio [aOR] = 3.41; 95% confidence interval [CI] = 2.80-4.16), ARI without NSAIDs use was associated with a 2.7-fold increased risk (aOR = 2.65; 95% CI = 2.29-3.06), and NSAIDs use only was associated with a 1.5-fold increased risk (aOR = 1.47; 95% CI = 1.33-1.62). Moreover, parenteral NSAIDs were associated with much higher risk in ARI patients (aOR = 7.22; 95% CI = 4.07-12.81). Nonsteroidal anti-inflammatory drugs use during ARI episodes, especially parenteral NSAIDs, was associated with a further increased risk of AMI.

Risk of Hospitalization for Heart Failure Associated with Cilostazol in Patients with Diabetes Mellitus: A Nationwide Case-Crossover Study

Risk of Hospitalization for Heart Failure Associated with Cilostazol in Patients with Diabetes Mellitus: A Nationwide Case-Crossover Study

Is Zolpidem Associated with Increased Risk of Fractures in the Elderly with Sleep Disorders? A Nationwide Case Cross-Over Study in Taiwan.

BackgroundWe conducted a study using a case-crossover design to clarify the risk of acute effects of zolpidem and benzodiazepine on all-sites of fractures in the elderly.Design of studyCase-crossover design.Methods and MaterialsElderly enrollees (n = 6010) in Taiwan’s National Health Insurance Research Database with zolpidem or benzodiazepine use were analyzed for the risk of developing fractures.ResultsAfter adjusting for medications such as antipsychotics, antidepressants, and diuretics, or comorbidities such as hypertension, osteoarthritis, osteoporosis, rheumatoid arthritis and depression, neither zolpidem nor benzodiazepine was found to be associated with increased risk in all-sites fractures. Subjects without depression were found to have an increased risk of fractures. Diazepam is the only benzodiazepine with increased risk of fractures after adjusting for medications and comorbidities. Hip and spine were particular sites for increased fracture risk, but following adjustment for comorbidities, the associations were found to be insignificant.ConclusionNeither zolpidem nor benzodiazepine was associated with increased risk of all-site fractures in this case cross-over study after adjusting for medications or comorbidities in elderly individuals with insomnia. Clinicians should balance the benefits and risks for prescribing zolpidem or benzodiazepine in the elderly accordingly.

Abstract 20635: Dipeptidyl-Peptidiase 4 Inhibitors and the Risk of Heart Failure - A Nationwide Case-Crossover Study

Introduction: Dipeptidyl-peptidiase 4 (DPP4) inhibitors, a new type of oral hypoglycemic agents, have been widely used in the treatment of type 2 diabetes mellitus (DM). However, recent studies showed that the use of DPP4 inhibitors, especially saxagliptin, could be associated with an increased risk of heart failure (HF). Methods: We conducted a retrospective case-crossover study by identifying DM patients aged 20 years and above hospitalized for HF between 2009 and 2011 from Taiwan National Health Insurance Database. Diagnosis codes from inpatient claims databases were used to ascertain the index date of hospitalization. For each patient, we defined case period as 1 to 30 days before the index date and control period as 91 to 120 days before the index date. The use of DPP4 inhibitors during the case and control periods were identified from the pharmacy claims database. Odds ratios (OR) and 95% confidence intervals (CIs) were estimated by a conditional logistic regression model. Results: A total of 47,506 patients hospitalized for HF (48.2% mean and 51.8% women) was included in the analysis (mean age: 72.7±12.4 years). Among them, 2,874 patients (6.05%) used sitagliptin in the case period, and 2,318 (4.88%) did in the control period. Use of other DPP4 inhibitors, i.e., saxagliptin and vildagliptin, was rare. The analysis of the discordant medication in the two periods showed that sitagliptin use was associated with an increased risk of HF (OR: 2.85, 95% CI: 2.46-3.30). Additional analyses using different time frames as the control period showed similar results. In contrast, there was no increased risk for HF in the use of sulfonylureas or metformin. Conclusions: The nationwide case-crossover study demonstrated that sitagliptin was associated with an increased risk of hospitalization for HF. Further studies are needed to examine whether the potential risk of HF is a class effect of DPP4 inhibitors.

Acute renal failure following oral sodium phosphate bowel preparation: a nationwide case-crossover study.

Oral sodium phosphate (OSP) is a cleansing agent for colonoscopy. Recent reports have cited an increased risk of acute renal failure (ARF) in OSP bowel purgative users, but this risk remains under debate. This study was performed to evaluate the association between OSP and ARF in patients who underwent colonoscopy. A population-based case-crossover study was conducted using the Korean Health Insurance Review and Assessment Service (HIRA) claims data from 1 January 2005 to 31 December 2009. The study population consisted of patients aged ≥ 50 years who underwent colonoscopies after an OSP prescription prior to their first hospitalization for ARF. For each patient, one hazard and four control periods were matched at specified time windows. Conditional logistic regression analysis was used to estimate the odds ratio (OR) and 95 % confidence interval (CI), adjusting for concomitant medications that could induce ARF. A total of 1105 patients were included (54 % male). The adjusted ORs for ARF related to the use of OSP when applying the 1-, 2-, 4-, 8-, or 12-week time windows were 3.7 (95 %CI 2.37 - 5.67), 3.5 (95 %CI 2.45 - 4.89), 3.0 (95 %CI 2.30 - 3.95), 2.4 (95 %CI 1.93 - 2.96), and 2.0 (95 %CI 1.69 - 2.46), respectively. When adopting an 8-week time window, the adjusted OR was 2.5 (95 %CI 1.98 - 3.16) for the subgroup without chronic renal failure. The use of OSP was significantly associated with ARF both in patients with and without co-morbidities.

An Association between Initiation of Selective Serotonin Reuptake Inhibitors and Suicide - A Nationwide Register-Based Case-Crossover Study

BackgroundTreatment with selective serotonin reuptake inhibitors (SSRI) is one of the most common treatments for depression. It is however not clear whether or not there is an increased short-term suicide risk during initiation with SSRI.MethodsA register-based nationwide case-crossover study including 5,866 suicides, 1,698 women and 4,168 men, from the Death Register 2007-2010 in Sweden. SSRI initiation was defined as a dispensed prescription of SSRI within 28 days prior to the date of suicide with no previous dispensed prescription of SSRI within 4 months prior that prescription. The control period took place one year earlier. Odds ratio (OR) was estimated using conditional logistic regression.ResultDuring the 28 day period prior to suicide 48 women and 138 men were exposed to SSRI initiation (while not being exposed in the control period) and 22 women and 43 men were exposed in the control period (while not being exposed in the case period). The OR for suicide after initiation with SSRI was 2.7 (95% CI: 1.6-44) for women, and 4.3 (95% CI: 3.0-6.1) for men. The highest OR was found 8-11 days after initiation with SSRI 9.7 (95% CI: 3.0-31.7) for women and men combined.ConclusionThe main limitation in this study is confounding by indication, but the descriptive question is however not confounded by indication. Together with plausible biological mechanisms and previous clinical and epidemiological observations our findings, linking initiation of SSRI to increased short-term suicide risk, deserve further attention specifically in the clinical setting.