Psychiatrics, relationship between schizophrenia and cigarette-smoking

1. Chidiebere John Uma

3. Schizophrenia is an illness affecting the
normal functioning of the brain.
It interferes with a person’s ability to
think, feel and act.

4. Confused thinking
Delusions
Hallucinations
Abnormal motor behavior
Negative symptoms

5. Activities such as eating and sex, which
give you pleasure or a feeling of well-
being, are correlated with a release of
dopamine
Nicotine activates dopaminergic-neurons
in the brain-reward system

7. Dopamine (DA) system
Mesolimbic Dopamine system
Ventral Tegmental Area (VTA)
Nucleus Accumbens (NAc)
Projections to Medial Prefrontal Cortex
BRAIN REWARD SYSTEMS

10. The combination of effects—
i. increasing dopamine release and
ii. decreasing the inhibitory [GABA]
response—
results in an amplification of the rewarding
properties of nicotine.

11. The rate of smoking in people with
schizophrenia is at least two to three
times (88%) that in the general
population.
Patients who smoke, smoke at heavier
rates than in the general population.
57% of new cases of schizophrenia are of
smokers.

12. WHY??

13. i. Aspects of the illness might lead more
patients to smoke
ii. Smoking might be an etiological factor
in schizophrenia
iii. Genetic and/or environmental factors
might lead both to nicotine addiction
and to schizophrenia

14. It has been suggested that smoking may
be a marker of a more severe illness
process.
Smokers have more severe symptoms
with higher scores on the Brief
Psychiatric Rating Scale for positive and
negative symptoms.

15. Patients smoke as a form of self-
medication with nicotine, which may
help regulate a dysfunctional mesolimbic
dopamine system.
It may increase dopamine release in the
pre-frontal cortex and alleviate positive
and negative symptoms.

16. It may be that repeated activation by
nicotine of the mesolimbic system over a
long time precipitates the onset of
schizophrenia in vulnerable individuals.
The earlier the age of starting smoking,
the earlier was the onset of psychotic
illness in women.

17. A small number of DNA sequences
(called SNPs) are known to be implicated
in both schizophrenia and smoking.
 SNPs within the NR4A3 gene
(rs1131339 and rs1405209) were
significantly associated with heavy
smoking.

18. Morbidity and mortality
Medication and side-effects
Economic considerations

19. There is an increase in deaths from
natural causes and the most common
causes are cardiovascular and
respiratory disease, both smoking-
related.

20. Cigarette smoke also increases the activity
of CYP 1A2 enzymes, thus decreasing the
concentration of many drugs, including
clozapine and olanzapine.
Patients who smoke require larger doses of
drugs than non-smokers to achieve the
same therapeutic effect.

21. Conversely, upon smoking cessation,
smokers may require a reduction in the
dosage of antipsychotics.

22. The average patient smokes about 26
cigarettes per day. At 3.19 Gel per
packet, this works out at 1,164.35 Gel
per year.
Very few patients work.

24. Smoking must be implicated in the
increased mortality in schizophrenia.
Smokers require higher doses of
antipsychotic medication.

25. A substantial proportion of the income of
smokers with schizophrenia is spent on
cigarettes.
Patients with schizophrenia have the right
to be offered treatment for their nicotine
addiction.

26. In schizophrenic patients, sustained-
release bupropion, an antidepressant,
alone or in combination with a nicotine
patch, resulted in significantly higher
long-term rates of smoking cessation
(30.3 and 35.5%, respectively) than use of
either the nicotine patch alone (16.4%) or
placebo (15.6%).

28.  http://www.ehd.org/health_tobacco_19.php
 https://teens.drugabuse.gov/teachers/mind-over-matter/nicotine/how-does-
nicotine-act-brain
 http://www.livestrong.com/article/214868-dopamine-smoking/
 https://en.wikipedia.org/wiki/Schizophrenia
 http://apt.rcpsych.org/content/6/5/327
 http://www.schizophrenia.com/smoke.htm#
 https://www.sciencedaily.com/releases/2016/04/160418091346.htm