Seizures during antidepressant treatment in psychiatric inpatients—results from the transnational pharmacovigilance project “Arzneimittelsicherheit in der Psychiatrie” (AMSP) 1993–2008

Rationale

There is little clinical data available about seizure rates in psychiatric inpatients, and there are no studies with reference data to the frequencies of antidepressant (AD) use for this important clinical population.

Objective

This study investigates seizure rates during AD treatment in psychiatric inpatient settings, drawn from the transnational pharmacovigilance programme Arzneimittelsicherheit in der Psychiatrie (AMSP) in relation to the known frequencies of ADs used in the participating clinics. Comparisons are made to former publications and their limitations.

Results

Seventy-seven cases were identified with grand mal seizures (GMS) during AD treatment between 1993 and 2008, with a total number of 142,090 inpatients under surveillance treated with ADs in the participating hospitals. The calculated overall rate of reported seizures of patients during AD treatment in this collective is 0.05 % for ADs imputed alone or in combination with other psychotropic drug groups and 0.02 % when only ADs were given and held responsible for GMS. The patients receiving tri- or tetracyclic ADs (TCAs) had a 2-fold risk to develop a seizure as compared to the overall average rate in this sample. In 11 cases, there was only one AD imputed—the majority of these cases (9/11) were TCA. Monotherapy with selective serotonin reuptake inhibitors (SSRI) or dual serotonin and noradrenaline reuptake inhibitors (SNRI) were never imputed alone in this sample.

Conclusions

The results of the study favour the assumption that SSRIs, noradrenergic and specific serotonergic antidepressants (NaSSA) and dual SNRI might be more appropriate than TCAs for the treatment of psychiatric patients with an enhanced seizure risk.     

Changes in the prescribing pattern of antidepressant drugs in elderly patients: an Italian,nationwide, population-based study

Background

Despite the high use of antidepressants (ADs) among the elderly, there is limited information about the prescribing pattern of these drugs in the Italian elderly population. The aim of this study was to analyze the trend in the use of ADs in the Italian elderly patients in the years 2003-2009, and specifically, to evaluate rates and predictors of AD treatment discontinuation in depressed older patients.

Methods

The nationwide general practice Health Search Database (HSD) was used to identify AD users aged 65 years old and over from 2003 to 2009. ADs were categorized as (1) selective serotonin reuptake inhibitors (SSRIs); (2) serotonin-norepinephrine reuptake inhibitors (SNRIs); (3) tricyclic antidepressants (TCAs); (4) noradrenergic and specific serotonergic antidepressants (NaSSAs); and (5) other ADs. Incidence and prevalence of AD use per 1,000 inhabitants was calculated by drug class and single compound. We also measured rates and predictors of AD discontinuation (i.e., treatment gap?≥?60 days) during the first year of therapy.

Results

Overall, 39,557 AD users ≥65 years (17 % of the total HSD elderly population) were included in the study. SSRIs were increasingly and most frequently prescribed ADs (102.7-195.3 per 1,000 over seven years). The most common indications for AD use were depression and anxiety. Overall, 14 % of AD users continued their AD medication without treatment gaps, 27 % were intermittent AD users and 58 % discontinued their ADs during the first year of follow-up. Specific AD classes such as TCAs and ‘other ADs were found to be predictors of discontinuation. In depressed patients, the use of NaSSas, TCAs and ‘other ADs as well the concomitant use of >5 drugs (other than ADs) and living in Southern Italy were more likely to predict discontinuation.

Conclusion

ADs, especially SSRIs, are widely and increasingly prescribed in elderly Italian patients in recent years. The observed high AD discontinuation rates are likely to impact the achievement of a therapeutic endpoint in depressed patients. Patients who are at high risk of AD discontinuation such as those receiving multi-drug therapy or living in Southern Italy should be monitored more closely to improve benefits of AD treatments.     

Selective serotonin re-uptake inhibiting antidepressants and the risk of overanticoagulation during acenocoumarol maintenance treatment

AIM

The aim of this study was to investigate the effects of co-medication with selective serotonin re-uptake inhibitors (SSRIs) on overanticoagulation during acenocoumarol maintenance treatment.

METHODS

All subjects from The Rotterdam Study who received acenocoumarol maintenance treatment between April 1 1991 and September 9 2009 were followed for the event of an international normalized ratio (INR) ≥6, until death, end of treatment or end of the study period. With the Andersen-Gill extension of the Cox proportional hazards model, risks for repeated events of overanticoagulation in relation to concomitant SSRI use were calculated.

RESULTS

The risk for overanticoagulation during acenocoumarol maintenance treatment was increased in combination with fluvoxamine (HR 2.63, 95% CI 1.49, 4.66) and venlafaxine (HR 2.19, 95% CI 1.21, 3.99). There was no increase in risk for the other SSRIs, but numbers of exposed cases were low for all SSRIs except paroxetine.

CONCLUSION

Fluvoxamine and venlafaxine were associated with a more than double risk of INR values ≥6 in acenocoumarol treated subjects.     

Serotonin transporter polymorphism and bleeding time during SSRI therapy

AIMS

Selective serotonin reuptake inhibitors (SSRIs), such as paroxetine, are associated with an increased risk of bleeding disorders, probably due to decreased platelet serotonin levels. Polymorphisms in the serotonin transporter gene (5-HTT) may influence the risk of SSRI-induced bleedings. The aim of this study was to investigate whether and to what extent the serotonin transporter polymorphism increases the bleeding time in paroxetine users.

METHODS

A prospective study, using routinely collected hospital and pharmacy data, was conducted among 43 patients between 18 and 70 years old and on >4 weeks of paroxetine therapy. The genotype for the serotonin transporter (5-HTTLPR), trough paroxetine levels, platelet function analyser (PFA)-closure time (collagen/epinephrine) and a complete blood count were assessed.

RESULTS

No significant difference was seen between the SS, SL, LL genotypes of the serotonin transporter and the PFA-closure time. None of the covariates had a significant influence on the association between the serotonin transporter polymorphism and the PFA-closure time. Age and von Willebrand factor showed the largest contribution, but not significant. No difference was seen between the PFA-closure time and the frequency of bruising and spontaneous bleedings between patients with at least one S allele and with the LL genotype.

CONCLUSION

Our prospective study does not support the assumption that paroxetine can cause a prolonged PFA-closure time during paroxetine therapy due to a serotonin transporter polymorphism. Old age, use of platelet inhibitors and a history of gastrointestinal bleeding remain the focus for SSRI-induced bleeding complications.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• From case reports it has become clear that selective serotonin reuptake inhibitors (SSRIs) can cause bleeding disorders.
• The causative mechanism is as yet unknown.
• Several publications have described the relationship between the serotonin transporter genotype and the prevalence of certain diseases such as depression, but few have focused on the relationship with side-effects of antidepressive drugs such as SSRIs.

WHAT THIS STUDY ADDS

• This study suggests that the association between SSRI therapy and prolonged bleeding time may not be related to the polymorphism of the serotonin transporter (5-HTTLPR) investigated.

     

Sudden death in patients receiving drugs tending to prolong the QT interval

AIMS

To examine risks of sudden death in the community associated with drugs grouped by their risk of causing torsades de pointes (TdP) and to explore the risks for individual drugs.

METHODS

Case–control study comparing prior drug intakes and morbidities, using the Arizona classification of drugs causing TdP. Participants included 1010 patients dying suddenly where post-mortem examination did not identify a clear cause of death, and 3030 matched living controls from primary care.

RESULTS

Noncardiac drug risk was posed by antipsychotics and antidepressants. Significantly raised odds ratios (ORs) were found for takers of typical and atypical antipsychotics, ORs [95% confidence interval] 3.94 (2.05, 7.55) and 4.36 (2.54, 7.51), and of selective serotonin reuptake inhibitors [SSRIs] rather than tricyclic antidepressants, ORs 2.21 (1.61, 3.05) and 1.44 (0.96, 2.13). No significant risk was associated with other, noncardiac or psychiatric drugs, OR 1.09 (0.85, 1.41). Arizona classified drugs considered to raise risk of TdP were associated with raised risk of sudden death, as were those only weakly associated with TdP and not considered to pose a risk in normal use, ORs 2.08 (1.45, 3.00) and 1.74 (1.33, 2.28), respectively.

CONCLUSIONS

Atypical and typical antipsychotic drug use were both strongly associated with raised risks, as were SSRIs. Tricyclic antidepressants were not associated with raised risks. The Arizona classification of risk of TdP was a poor predictor of likelihood of noncardiac drug-associated sudden death.     

A nationwide prospective study on prescribing pattern of antidepressant drugs in Italian primary care

Purpose

Our purpose was to explore antidepressant drug (AD) prescribing patterns in Italian primary care.

Methods

Overall, 276 Italian general practitioners (GPs) participated in this prospective study, recruiting patients >18 years who started AD therapy during the enrolment period (January 2007 to June 2008). During visits at baseline and 3, 6, and 12 months, data about patients’ characteristics and AD treatments were collected by the GPs. Discontinuation rate among new users of AD classes [i.e., selective serotonin reuptake inhibitors (SSRI); tricyclics (TCAs); other ADs) were compared. Logistic regression analyses were performed to identify predictors of AD discontinuation.

Results

SSRIs were the most frequently prescribed ADs (N?=?1,037; 75.3 %), especially paroxetine and escitalopram. SSRIs were more likely to be prescribed because of depressive disorders (80 %), and by GPs (51.1 %) rather than psychiatrists (31.8 %). Overall, 27.5 % (N?=?378) of AD users discontinued therapy during the first year, mostly in the first 3 months (N?=?242; 17.6 %), whereas 185 (13.4 %) were lost to follow-up. SSRI users showed the highest discontinuation rate (29 %). In patients with depressive disorders, younger age, psychiatrist-based diagnosis, and treatment started by GPs were independent predictors of SSRI discontinuation.

Conclusions

In Italy, ADs—especially SSRIs—are widely prescribed by GPs because of depressive/anxiety disorders. Active monitoring of AD users in general practice might reduce the AD discontinuation rate.     

A prospective observational study to evaluate safety reporting of antidepressants at a tertiary care hospital in India

Objective:

This prospective observational study was carried out to identify the prevalence and Severity of ADRs of antidepressant in a tertiary care teaching hospital.

Materials and Methods:

Patients prescribed with at least one antidepressant were randomly selected and monitored for adverse drug reactions (ADRs), irrespective of their age and gender.

Results:

Of the 401 patients who received antidepressants, 170 patients (42.39%) experienced 204 ADRs. Selective serotonin receptor inhibitors (SSRIs) [110 (53.92)] was the most common therapeutic class of drugs associated with ADRs. Gastrointestinal system [54 (26.47)] was most commonly affected system organ class. Dry mouth (n = 30) and diaphoresis (n = 21) were the most frequently reported ADRs. As assessed by the World Health organization (WHO) probability scale, 61% of the ADRs were ‘probable’ causality. Among all the ADRs, 22.54% (46) were preventable. Majority of the ADRs [(n = 184) 90.17%] were ‘mild’ in their severity.

Conclusion:

In this study, incidence of adverse reaction to antidepressants was 42.3% were the most comman SSRI inplicated drug group for the ADRs.KEY WORDS: Adverse effects, antidepressants, depression, psychiatry, psychiatric patients     

Remission, dropouts, and adverse drug reaction rates in major depressive disorder: a meta-analysis of head-to-head trials

OBJECTIVE: To summarize remission rates and dropouts due to adverse drug reactions (ADRs) or lack of efficacy (LoE) of serotonin-norepinephrine reuptake inhibitors (SNRIs), selective serotonin-reuptake inhibitors (SSRIs), and tricyclic antidepressants (TCAs) in treating major depressive disorder. METHODS: We searched MEDLINE, EMBASE, IPA, and the Cochrane International Library from 1980-2005. Meta-analysis summarized outcomes from head-to-head randomized clinical trials comparing >or= 2 drugs from three antidepressants classes (SNRIs, and/or SSRIs, and/or TCAs) followed by >or= 6 weeks of treatment. Remission was a final Hamilton Depression Rating Scale (HAMD) score 0.05 for SNRIs versus TCAs; p < 0.001 for TCAs versus SSRIs and SNRIs versus SSRIs). When categorized as inpatients (n = 582) and outpatients (n = 1613), SNRIs had the highest remission rates (52.0% for 144 inpatients and 49.3% for 559 outpatients). SNRIs had lowest overall dropouts (26.1%), followed by SSRIs (28.4%), and TCAs (35.7%). Dropouts due to ADRs and LoE were 10.3% and 6.2% for SNRIs, 8.3% and 7.2% for SSRIs, and 19.8% and 9.9% for TCAs, respectively (p > 0.05 for ADR dropouts only). One limitation was the inclusion of only venlafaxine-XR; results may not be the same for immediate release forms. In addition, few studies reported remission rates. CONCLUSIONS: SNRIs had the highest efficacy remission rates (statistically significant for inpatients and outpatients), and the lowest overall dropout rates, suggesting clinical superiority in treating major depression.     

The effect of selective serotonin re-uptake inhibitors on the risk of myocardial infarction in a cohort of patients with depression

AIM

To evaluate whether selective serotonin re-uptake inhibitor (SSRI) exposure influences the risk of myocardial infarction (MI) in patients with depression.

METHODS

This study included 693 patients with MI (cases) and 2772 controls. Conditional logistic regression was used to calculate the odds ratio (OR).

RESULTS

SSRI exposure may be associated with a reduced MI risk (OR = 0.77, 95% CI 0.57, 1.03). However, reduced risk was only observed with longer term use (OR = 0.73, 95% CI 0.53, 1.00) and not with shorter term use (OR = 1.15, 95% CI: 0.65, 2.05).

CONCLUSIONS

Only longer term use of SSRIs was associated with reduced MI risk, suggesting that other mechanisms, besides an acute anti-platelet effect, may reduce MI risk.     

Perceived adverse drug reactions among non-institutionalized children and adolescents in Germany

AIMS

Little has been reported on the risks of drug use in the general child population. This study investigated perceived adverse drug reactions (ADRs) among non-institutionalized children in Germany.

METHODS

All medicines used in the last 7 days before the medical interview were recorded among the 17 450 children aged 0–17 years who participated in the 2003–06 German Health Interview and Examination Survey for Children and Adolescents (KiGGS). Perceived ADRs were reported by the children''s parents and confirmed by trained medical professionals during the medical interview.

RESULTS

One hundred and fifty-seven medicines were involved in the occurrence of 198 perceived ADRs in 153 patients. This corresponded to 1.1% of total used drugs, 0.9% (95% confidence intervals 0.7, 1.1%) of all children, and 1.7% (1.4, 2.1%) of children treated with medications. About 40% of all perceived ADRs involved gastrointestinal disorders and 16% involved skin tissue disorders. Perceived ADRs were most frequently reported in relation to drugs acting on the nervous system (25.8%), followed by systemic anti-infectives (18.7%) and drugs acting on the respiratory system (16.2%). Risk factors for perceived ADRs included older age groups, polypharmacy (≥2) and a poor health status.

CONCLUSION

Perceived ADRs in the general child population were clustered with gastrointestinal disorders and subcutaneous tissue disorders. They appeared to be mild and at the lower limits of the range reported in other studies. Health surveys covering the use of a diverse range of drugs might be suitable for computing ADR prevalence and identifying risk factors among non-institutionalized children. They should be taken into account together with other pharmacovigilance systems.     

Utility of organotypic raphe slice cultures to investigate the effects of sustained exposure to selective 5-HT reuptake inhibitors on 5-HT release

BACKGROUND AND PURPOSE

Selective 5-hydroxytryptamine (5-HT, serotonin) reuptake inhibitors (SSRIs) are widely used antidepressants and their therapeutic effect requires several weeks of drug administration. The delayed onset of SSRI efficacy is due to the slow neuroadaptive changes of the 5-hydroxytryptaminergic (5-HTergic) system. In this study, we examined the acute and chronic effects of SSRIs on the 5-HTergic system using rat raphe slice cultures.

EXPERIMENTAL APPROACH

For organotypic raphe slice cultures, mesencephalic coronal sections containing dorsal and median raphe nuclei were prepared from neonatal Wistar rats and cultured for 14–16 days.

KEY RESULTS

Acute treatment with citalopram, paroxetine or fluoxetine (0.1–10 µM) in the slice cultures slightly increased extracellular 5-HT levels, while sustained exposure for 4 days augmented the elevation of 5-HT level in a time-dependent manner. Sustained exposure to citalopram had no effect on tissue contents of 5-HT and its metabolite, expression of tryptophan hydroxylase or the membrane expression of 5-HT transporters. The augmented 5-HT release was attenuated by Ca²⁺-free incubation medium or treatment with tetrodotoxin. Experiments with 5-HT_1A/B receptor agonists and antagonists revealed that desensitization of 5-HT₁ autoreceptors was not involved in the augmentation of 5-HT release. Finally, co-treatment with an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate, but not an N-methyl-d-aspartate, receptor antagonist, suppressed this augmentation.

CONCLUSION AND IMPLICATIONS

These results suggest that sustained exposure to SSRIs induces the augmentation of exocytotic 5-HT release, which is caused, at least in part, by the activation of AMPA/kainate receptors in the raphe slice cultures.