Antipsychotic Use and Idiopathic Venous Thromboembolism

This research critique examines the association between antipsychotic use and idiopathic venous thromboembolism. The study assesses the strengths and limitations of previous research, the methods applied, and the findings. The study concludes that there is a slight relationship between antipsychotic drugs and the occurrence of venous thromboembolism.

Research Critique
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Introduction
Antipsychotics are a class of medical drugs which are primarily used in medication process
and management of psychosis conditions such as hallucinations, paranoia, disorder, and
delusions. It has been increasingly used in the management of nonpsychotic. The drugs are
often useful in effective relief of pain and symptoms for short duration of time. First
generation antipsychotics are referred to as do pine receptor antagonists- DRA. These drugs
include acetophenazine, dibenzoxazepines, perphenazine, prochlorperazine, acetophenazine
and many more [1].
The second generation antipsychotic drugs include serotonin-dopamine antagonists which are
generally antipsychotics. Currently, FDA organization have approved 12 types of atypical
antipsychotics. They include ziprasidone, iloperidone, paliperidone, asenapine, quetiapine,
aripiprazole, paliperidone, brexpiprazole, and clozapine [2].
These drugs have been utilized for various indications. The first and second generation
antipsychotic drugs are used for the management of schizophrenia and schizoaffective states
for the management of acute episodes of psychosis and therapy maintenance. First
generations have shown better and effective means of treating symptoms of hallucinations
among others, further they lower the risks of repeated episodes of psychosis.
First generation drugs have shown improved care on managing acute mania with psychotic
symptoms. Second generation drugs except clozapine are effective in the management of
acute symptoms of acute mania. They mostly used with mood stabilizers drugs such as
lithiumcarbamezipaine and valproic acid. Further, first and second generation drugs have
shown effectiveness in treating and managing major depressive disorders with antidepressant
being the treatment of choice for depression with psychotic features. Other indications of first
and second generation include management of borderline disorders, Tourette disorders;
dementia and delirium and managing the substance-induced psychotic disorder. Clozapine
has been used often when a patient fail to yield the needed results in various trials [4].
The first generation of drugs works by an inhibitor of the dopaminergic neurotransmission.
They effectively block about 72% of the D2 dopamine receptors located in the brain. Further,
they consist of noradrenergic, cholinergic and histaminergic effect action. The second
generation drugs act by blocking the receptors of Dopamine D2 together with serotonin

receptor action. The 5-HT2A subtype of serotonin is commonly used. The associative adverse
effects have been noted with extrapyramidal side effects. Anticholinergic effects dry mouth,
urine retention and constipation [1].
Strengths and limitations of the study
The study assessed recipient’s subjects of antipsychotic use, below the aged 60 years.
Computer generated medical diagnosis were assessed. The study strengths entailed diagnoses
generated using computer diagnosis records. Further verification process was undertaken,
letters were sent to the hospital facility to confirm their admission thus eliminating omission
error. Inclusion criteria entailed a positive diagnosis of venous thromboembolism impedance
plethysmography, venogram, ultrasonography, or doppler test, and pulmonary embolism
through confirmation of ventilation-perfusion scan. Further, the stud methodology excluded
discharge summaries subjects with previous venous thromboembolism and history of trauma,
pregnancy or surgery history in the 6 months.
The study, however, despite its findings’ between conventional antipsychotic drugs and
venous thromboembolism is consistent with other research little information is provided
between the relation of atypical; antipsychotic and idiopathic venous thromboembolism. Thus
could not create an effective causality. Thus, making it a limitation for none generalization of
the results.
Critical appraisal
Event definition and applied methods
The studies previously conducted have shown that conventional antipsychotic drugs are not
free from cardiovascular and other risks factors and other spontaneous reports did not provide
controls [5]. Antipsychotic drugs are common medication management drugs with the
potential fatal occurrence of venous thromboembolisms public health hazard. These study
employed population-based approach nets control analysis to identify the relationship
between antipsychotic drugs and management of risk of development of the first episode,
idiopathic venous thromboembolism in the bigger cohort using UK based general practice
research database.
Exposure definition and methods applied

Medication data exposures were produced for computer prescriptions. Each case and control
history was assessed. Exposure definition was derived from three key periods’ episodes;
current, recent and non exposed. The current usage of antipsychotic use was defined between
1-60 days, recent antipsychotic use was drug prescription of between 61-120 days while the
exposure was prescribed with 1-120 days before initiation of any indexing. The antipsychotic
drug was divided into three major groups according to their chemical structure and activity
into two crucial groups based on its potency.
Idiopathic venous thromboembolism was defined with occurrence or absence of important
medial risks factors with conditions which predispose immobilization and recurring hospital
admission.
Population selection procedures
Identification of cases and controls was undertaken with individuals having first-time
diagnosis f venous thromboembolism between Jan 1990 and Oct 1995, were included in the
study. The identification process followed a computer recorded medical diagnosis with a
modification on the Oxford Medical Information Systems. Identification of potential cases
was based on admission and treatment o the use of anticoagulants for management of venous
thromboembolism. Discharge letters were obtained from the hospital facilities to confirm the
hospital admissions and mortality records and verification documents. For inclusion criteria
to be successful, venogram, ultrasound, Doppler test, impedance, and plethysmography, had
to have a confirmation of ventilation-perfusion scan.
The sensitivity of the study to biases
The study sensitivity was improved with the use of case-patients with 60
years and below on date of diagnosis and negative records from other
medical conditions linked to elevated levels of venous thromboembolism.
Further exclusion entailed patients with discharge summaries of venous
thromboembolism and history of trauma, surgery in the last 6 months and
pregnancy. Despite this, the study did not confirm any clinical record of
six included in the study, making biased inclusion.
The baseline data was randomly selected yielding four controls matching
the cases on age, sex, general practice and index dates was obtained.

Further same exclusion criteria were used for cases applied as controls,
and if no controls if they were included.
Causality criteria fitness
The study methodology and results obtained shows evidence s of
causality criteria. Based on the Bradford Hill criteria for causality, the
strength size of the sample size shows strong g association and causal
effect. The results can be reproduced based on the manner in which the
methodology process was undertaken. The study illustrates that the
findings are in concordance with previous research undertaken thus
improving its consistency. The study, however, shows lifted specificity
level. Little information was yielded on the relation of the between
antipsychotic drug and idiopathic venous thromboembolism. The study did
not establish a clear temporal effect on cause and effect thus
recommended for further studies to assess any significant relation.
Further, this will enable to obtain biological gradient which could have
indicated greater exposure leading to higher incidence effects which
lacked in the study. The study further did not yield any meaningful
plausibility mechanism.
Antipsychotic use and idiopathic venous thromboembolism
Association
Based on the study assessment, the use of the conventional antipsychotic
drug is linked to increased association of venous thromboembolism. There
is an established association on the usage of the drug and is observed to
be profound during the first 3 months of its usage. Thus the causal
relationship established in the study could not be conclusive since dos
effect relationship could not be immediately be established leading to
susceptibility. Thus there is a slight relationship between the antipsychotic
drugs and the use of antipsychotic drugs.

References
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eDelphi consensus study. Clinical Interventions in Aging 2018;Volume 13:2107-
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Quality in Transitions for People with Dementia: a Prospective Observational Study.
Canadian Geriatrics Journal 2019;22:13-22. doi:10.5770/cgj.22.332
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thromboembolism: a case-control study. The Lancet 2000;356:1219-1223.
doi:10.1016/s0140-6736(00)02784-7