David Baxter PhD
Late Founder
Smoking interferes with treatment for bipolar mania
By Andrew Czyzewski
01 August 2008
J Affect Disord 2008; 110: 126-134
Cigarette smoking is associated with worse treatment outcomes in acutely manic patients with bipolar disorder, research shows.
Investigator Felicity Ng (University of Melbourne, Victoria, Australia) and colleagues comment: "Rather than allowing the passive acceptance of smoking as a prevalent lifestyle habit among patients with mental illness to continue, clinicians could adopt an alternative stance that views smoking as a comorbid condition requiring active intervention."
Around one third of patients with bipolar disorder are smokers and the odds ratios for nicotine dependence are estimated to be 3.9 and 3.5 for bipolar I and II disorders, respectively, in comparison with the general population.
Studies have shown that lifetime history of smoking is significantly related to earlier onset of the first depressive or manic episode, greater symptomatic severity, poorer functioning, and a lifetime history of suicide attempt, comorbid anxiety disorders and substance dependence.
"Despite existing literature investigating the relationship between smoking and bipolar disorder course, the impact of smoking on the efficacy of bipolar treatment has yet to be explored in the context of rigorous clinical trial data," Ng et al. note in the Journal of Affective Disorders.
In the current study, the researchers reviewed evidence from three randomized controlled trials of antipsychotics for acutely manic patients with bipolar disorder.
From a total of 807 patients, over half (n=467) were smokers.
When data from all three studies were pooled, nonsmokers showed significantly greater improvements than smokers on both Young Mania Rating Scale (YMRS) total score (DF 787; F statistics= 9.57; P=0.002) and Clinical Global Impressions scale for bipolar disorder (CGI-BP) mania severity scores (DF 787; F statistics= 12.26; P=0.0005).
Notably, the impact of active smoking on treatment outcomes became apparent in the medium- to-long-term rather than in the first few weeks of treating acute mania.
The researchers note that nicotine, the primary psychoactive compound in tobacco smoke, acts as an agonist at nicotinic cholinergic receptors, mediating the widespread release of neurotransmitters such as dopamine, noradrenaline, serotonin, γ-aminobutyric acid (GABA) and glutamate.
Since antipsychotics act as serotonin and dopamine antagonists, smoking may interfere with their therapeutic action.
Regardless of the underlying mechanism Ng and colleagues advise: "For bipolar and depressive disorders, patients may benefit from being specifically counselled on the importance of addressing smoking as part of their mood disorder management."
Abstract
By Andrew Czyzewski
01 August 2008
J Affect Disord 2008; 110: 126-134
Cigarette smoking is associated with worse treatment outcomes in acutely manic patients with bipolar disorder, research shows.
Investigator Felicity Ng (University of Melbourne, Victoria, Australia) and colleagues comment: "Rather than allowing the passive acceptance of smoking as a prevalent lifestyle habit among patients with mental illness to continue, clinicians could adopt an alternative stance that views smoking as a comorbid condition requiring active intervention."
Around one third of patients with bipolar disorder are smokers and the odds ratios for nicotine dependence are estimated to be 3.9 and 3.5 for bipolar I and II disorders, respectively, in comparison with the general population.
Studies have shown that lifetime history of smoking is significantly related to earlier onset of the first depressive or manic episode, greater symptomatic severity, poorer functioning, and a lifetime history of suicide attempt, comorbid anxiety disorders and substance dependence.
"Despite existing literature investigating the relationship between smoking and bipolar disorder course, the impact of smoking on the efficacy of bipolar treatment has yet to be explored in the context of rigorous clinical trial data," Ng et al. note in the Journal of Affective Disorders.
In the current study, the researchers reviewed evidence from three randomized controlled trials of antipsychotics for acutely manic patients with bipolar disorder.
From a total of 807 patients, over half (n=467) were smokers.
When data from all three studies were pooled, nonsmokers showed significantly greater improvements than smokers on both Young Mania Rating Scale (YMRS) total score (DF 787; F statistics= 9.57; P=0.002) and Clinical Global Impressions scale for bipolar disorder (CGI-BP) mania severity scores (DF 787; F statistics= 12.26; P=0.0005).
Notably, the impact of active smoking on treatment outcomes became apparent in the medium- to-long-term rather than in the first few weeks of treating acute mania.
The researchers note that nicotine, the primary psychoactive compound in tobacco smoke, acts as an agonist at nicotinic cholinergic receptors, mediating the widespread release of neurotransmitters such as dopamine, noradrenaline, serotonin, γ-aminobutyric acid (GABA) and glutamate.
Since antipsychotics act as serotonin and dopamine antagonists, smoking may interfere with their therapeutic action.
Regardless of the underlying mechanism Ng and colleagues advise: "For bipolar and depressive disorders, patients may benefit from being specifically counselled on the importance of addressing smoking as part of their mood disorder management."
Abstract
