Zolpidem Use and Suicide Death in South Korea: A Population-Based Case-Control Study

Zolpidem use and risk of suicide: A systematic review and meta-analysis

INTRODUCTION

Zolpidem is one of the most commonly prescribed nonbenzodiazepine hypnotic drugs for insomnia. Published epidemiological studies linked zolpidem with the risk of suicide. However, to date, no meta-analysis investigated this association. Hence, we systematically reviewed and meta-analysed the current evidence from real-world studies reporting the risk of suicide with the use of zolpidem.

METHODS

Medline (Ovid), Embase (Ovid), and PsycINFO databases were searched from inception till June 2021 for real-world evidence studies reporting the risk of suicide with the use of zolpidem. The quality assessment of included studies was assessed using the New-Castle Ottawa Scale (NOS). Random-effect meta-analysis was performed using a generic inverse variance method.

RESULTS

This meta-analysis was based on four studies with 344,753 participants, of which 42,279 were zolpidem users. The methodological quality of all the included studies was of high quality. A significantly increased risk of suicide or suicide attempt was found in zolpidem users compared to non-users, with a pooled relative risk of 1.88 (95% CI: 1.54 - 2.30). Furthermore, an increased risk of suicidal death was observed in zolpidem users compared to non-users, with a pooled relative risk of 1.82 (95% CI: 1.43 - 2.30). Dose-response analysis also revealed a significantly increased risk of suicide in patients receiving ≥ 180cDDD (cumulative defined daily doses) of zolpidem (124 times), followed by 90-179cDDD (113 times) and <90cDDD (93 times) of zolpidem compared to non-users.

CONCLUSION

In conclusion, zolpidem use was associated with an increased risk of suicide or suicide attempt and suicidal death. Therefore, careful prescribing practices must be followed by considering the risk-benefit profile.

Early psychiatric referral after attempted suicide helps prevent suicide reattempts: A longitudinal national cohort study in South Korea

INTRODUCTION

Although people who attempted suicide tend to repeat suicide attempts, there is a lack of evidence on the association between psychiatric service factors and suicide reattempt among them.

METHODS

We used a nationwide, population-based medical record database of South Korea to investigate the use of psychiatric services before and after the index suicide attempt and the association between psychiatric service factors after the index suicide attempt with the risk of suicide reattempt.

RESULTS

Among 5,874 people who had attempted suicide, the all-cause mortality within 3 months after the suicide attempt was 11.6%. Among all subjects who attempted suicide, 30.6% of them had used psychiatric services within 6 months before the suicide attempt; 43.7% of them had used psychiatric services within 3 months after the suicide attempt. Among individuals who had visited clinics following attempted suicide, the cumulative incidence of suicide reattempt over a mean follow-up period of 5.1 years was 3.4%. About half of suicide reattempts occurred within 1 year after the index suicide attempt. Referral to psychiatric services within 7 days was associated with a decreased risk of suicide reattempt (adjusted hazard ratio, 0.51; 95% confidence intervals, 0.29-0.89).

CONCLUSION

An early psychiatric referral within 1 week after a suicide attempt was associated with a decreased risk of suicide reattempt.

Interrupted Time Series Analysis of Changes in Zolpidem Use Due to Media Broadcasts

Media has become a major source of information on health and plays a role in the decision-making process on health topics. We aimed to evaluate the association between zolpidem use and media broadcasts that reported the suicide risk. We obtained the data of adult outpatients who have been prescribed zolpidem or other hypnotics from the National Patient Sample database (2015–2017). We evaluated the change in zolpidem or other hypnotic prescription trends based on the prescription rate and average daily prescribed dose before and after July 2016, using interrupted time series analysis. A total of 129,787 adult patients had at least one zolpidem prescription in 3 years. The prescription rate of zolpidem after the broadcast decreased significantly by 0.178% (95% confidence interval (CI): −0.214, −0.142), whereas that of other hypnotic users did not differ from that before the broadcast (−0.020%, 95% CI: −0.088, 0.047). However, the trends in the prescription rate before and after the broadcast did not differ for zolpidem and other hypnotics. Broadcasting medication safety through major public media could have an effect on medication use. After broadcasting about the suicide risk of zolpidem, its overall prescription rate decreased immediately, but the trend was not changed.

Prescription medications for insomnia are associated with suicidal thoughts and behaviors in two nationally representative samples

STUDY OBJECTIVES

Z-drugs (eszopiclone, zolpidem, and zaleplon) are commonly used for insomnia but are also associated with suicide risk. However, it is unclear if this association is unique to Z-drugs. Therefore, the present study estimated the associations between multiple prescription insomnia medications and suicidal thoughts and behaviors.

METHODS

Data were acquired from the National Survey on Drug Use and Health for 2015-2018 and the National Health and Nutrition Examination Survey for 2005-2018. Samples were balanced on sociodemographic and mental health covariates using inverse probability of treatment weighting. Associations of Z-drugs, trazodone, and sedative benzodiazepines (temazepam, triazolam, flurazepam) with suicidal ideation, planning, and attempts were estimated using binomial logistic regression.

RESULTS

In the National Survey on Drug Use and Health, Z-drugs were associated with suicidal ideation (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.14-1.54]), suicide planning (OR, 1.44; 95% CI, 1.19-1.75), and suicide attempts (OR, 1.45; 95% CI, 1.13-1.86) after adjusting for age, sex, race/ethnicity, income, depression, illicit substance use, and the 6-item Kessler Psychological Distress Scale and World Health Organization Disability Assessment Schedule II scores. When analyses accounted for the same factors, sedative benzodiazepines were associated with suicide attempts (OR, 1.76; 95% CI, 1.06-2.87) but not suicidal ideation (OR, 1.37; 95% CI, 0.99-1.88) or suicide planning (OR, 1.39; 95% CI, 0.97-2.00). In the National Health and Nutrition Examination Survey, Z-drugs were associated with suicidal ideation (OR, 2.44; 95% CI, 1.41-4.22), as was trazodone (OR, 2.33; 95% CI, 1.45-3.75), after analyses adjusted for age, sex, race/ethnicity, and exposure to various psychotropic medications.

CONCLUSIONS

Multiple classes of prescription insomnia medications are associated with suicidal thinking and behaviors, even after analyses adjusted for measures of mental health.

Oseltamivir and the Risk of Neuropsychiatric Events: A National, Population-based Study

BACKGROUND

Reports of serious neuropsychiatric events (NPEs), specifically suicide/suicide attempts, following the use of oseltamivir have led to public concerns. Our aim in this study was to determine whether an association exists between oseltamivir use and NPEs.

METHOD

This study was a population-based, retrospective, cohort study on a random sample of 50% of individuals in the Korean National Health Insurance Service (KNIS) database aged ≥8 years who were diagnosed with influenza between 2009 and 2017. The primary exposure was oseltamivir prescription at the time of influenza diagnosis, whereas the primary outcome was a diagnosis of an NPE within 30 days after the influenza diagnosis. Information on oseltamivir prescription, diagnoses of NPEs, demographic characteristics, comorbidities, drugs prescribed within the year before influenza diagnosis, and healthcare utilization were extracted from the KNIS database.

RESULTS

Of 3 352 015 individuals included in the analysis, 1 266 780 (37.8%) were prescribed oseltamivir. The incidence of NPEs was 0.86% and 1.16% in patients who were and were not prescribed oseltamivir, respectively (hazard ratio [HR], 0.74; 95% confidence interval [CI], .73 to .75; P < .001). Oseltamivir use was not associated with a difference in the overall risk of NPEs in the adjusted model (HR, 0.98; 95% CI, .96 to 1.01; P = .16), but the incidence of moderate-to-severe NPEs was significantly lower in those prescribed oseltamivir (HR, 0.92; 95% CI, .88-.96; P < .001).

CONCLUSION

Treating influenza with oseltamivir does not increase the risk of NPEs. Thus, public concern regarding its use is unwarranted.

Risks of suicide attempts after prescription of zolpidem in people with depression: a nationwide population study in South Korea

OBJECTIVES

To investigate the association between zolpidem prescription and suicide attempts in people with depression.

METHODS

A nationwide, population-based electronic medical records database from the Health Insurance Review & Assessment Service of South was used to investigate the incidence rate ratios (IRRs) of suicide attempts and probable suicide attempts in people with depression before and after zolpidem prescription using self-controlled case series design.

RESULTS

In a total of 445 people who attempted suicide and 23 141 people who attempted probable suicide attempt, the IRRs of suicidal behavior during the risk periods before and after zolpidem prescription increased compared with those at the baseline. The IRRs gradually increased and peaked immediately before the prescription of zolpidem. The IRR was 70.06 (95% CI: 25.58-191.90) on day 2 before zolpidem prescription and 63.35 (95% CI: 22.99-174.59) on day 1 after zolpidem prescription in the suicide attempt group. The IRR was 24.07 (95% CI: 20.50-28.26) on the day before zolpidem prescription and 14.96 (95% CI: 12.21-18.34) on the day after zolpidem prescription in the probable suicide attempt group. The ratios declined eventually after zolpidem was prescribed.

CONCLUSIONS

Although zolpidem prescription was associated with an increased risk of suicide attempts in people with depression, the risk increased and peaked immediately before zolpidem prescription. The risk declined gradually thereafter. This result indicates that the risk of suicide attempts increases at the time of zolpidem prescription. However, zolpidem prescription does not contribute to additional increase in the risk of suicide attempts.

Application of scanning electron microscopy in the auxiliary diagnosis of death caused by potassium chloride intravenous injection: a case report

To determine the cause of death, in addition to routine autopsy, some assisted techniques are imperative to achieve a definite diagnosis. Herein, we report a case of 36-year-old man who was found dead in his apartment. Medical drug containers (potassium chloride, zolpidem, and propofol) and medical instruments (syringes and indwelling needles) were also found at the scene. An autopsy revealed large amounts of whitish foamy and brown liquid in the trachea and bronchi, and histopathological findings showed remarkable pulmonary congestion and edema. An injection mark with hemorrhage on the right wrist was found on external examination. Results of forensic pathology excluded the presence of mechanical injuries, mechanical asphyxia, embolism, and other fatal diseases. The data of toxicological analysis showed that concentrations of zolpidem and propofol in blood were appreciably higher than the therapeutic dose but they did not reach the absolute lethal dose. Moreover, the level of potassium in the blood and vitreous humor was higher than the expected concentration after death. A scanning electron microscope (SEM) combined with energy-dispersive X-ray microanalyzer (EDX) was subsequently applied to assess the skin samples collected from bilateral wrists. Ultrastructural observation discovered continuous visible interruption of the skin around the injection mark, and energy spectrum analysis revealed statistically significantly higher potassium content of the skin over the right wrist than the left wrist. Comprehensive analysis concluded that the deceased had died of potassium chloride intravenous injection under the zolpidem and propofol effects.

Temporal association between zolpidem medication and the risk of suicide: A 12-year population-based, retrospective cohort study

There have been concerns about abuse and unnecessary chronic administration of zolpidem, and zolpidem's relation to suicide risk. To investigate the temporal association of zolpidem with the risk of suicide, we conducted a 12-year, population-based, retrospective cohort study on the National Health Insurance Service-National Sample Cohort (NHIS-NSC), South Korea. Data were collected from 2002 to 2013 from the NHIS-NSC, and data cleaning was performed for 1,125,691 subjects. Cox proportional hazards regression analysis was used to investigate the correlation over time between zolpidem medication and suicide. Over intervals commencing after 80 months of observation, the adjusted hazard ratio of suicides associated with the use of the zolpidem was 2.01 (95% CI: 1.58-2.56; p < 0.001). The mean cumulative number of days of zolpidem prescription was significantly longer in the suicide group than in the non-suicide group after log-transformation (p = 0.005). Cases of chronic use of zolpidem (over six months or one year) were significantly more common in the suicide group compared to the non-suicide group (p = 0.002 and 0.005, respectively). Subjects who received zolpidem medication had a significantly higher risk of suicide after at least 80 months of observation, suggesting a long-term increased suicide risk associated with insomnia exposed to zolpidem medication.

Concurrent use of benzodiazepines, antidepressants, and opioid analgesics with zolpidem and risk for suicide: a case-control and case-crossover study

PURPOSE

To evaluate whether the concurrent use of benzodiazepines, antidepressants, and opioid analgesics with zolpidem increases the risk of suicide or triggers suicide compared with the use of zolpidem alone.

METHODS

We conducted a case-control and case-crossover study using the Korean National Health Insurance Service-National Sample Cohort database. Cases were older than 20 years with a suicide record (International Codes of Disease 10th Revision codes: X-60-X84 and Y87.0 intentional self-harm) between January 1, 2004, and December 31, 2013. For case-control design, ten controls were matched to each case by age, sex, index year, region, income, and health insurance type. For case-crossover analysis, we set hazard period to 60 days and assigned five corresponding sets of control periods of equal length. Exposure was assessed during 60 days before suicide for combinations of benzodiazepines, antidepressants, opioid analgesics with zolpidem against zolpidem alone. We conducted a conditional logistic regression to estimate odds ratios (ORs) and their 95% confidence intervals (CIs).

RESULTS

In the case-control study, the risk of suicide was 2.80-fold higher in cases taking benzodiazepines and antidepressants with zolpidem than in those taking zolpidem alone (adjusted OR [aOR], 2.80; 95% CI, 1.38-5.70). However, in the case-crossover study, suicide risk showed no significant difference (crude OR [cOR], 0.92; 95% CI, 0.55-1.52) and was underpowered.

CONCLUSIONS

The results of the traditional case-control study confirmed that the concurrent use of benzodiazepines and antidepressants with zolpidem was associated with an increased risk of suicide compared with the use of zolpidem alone. However, there was no significant difference in the magnitude of risk in the within-person comparison design.