Haemodynamic and neuroendocrine consequences of stopping smoking--a controlled study

The haemodynamic and neuroendocrine consequences of stopping smoking for a 6 week period were studied in thirty-three smokers and their matched controls. Complete smoking cessation was associated with a significant fall in adrenaline and cortisol levels, consistent with the withdrawal of a nicotine stimulus to adrenomedullary and cortical activity. Supine systolic and diastolic blood pressure did not change significantly. However, the response to a cold pressor stimulus was altered with a delay in return of systolic blood pressure to basal values. This study has been unable to confirm findings from epidemiological studies of lower blood pressure in smokers. However, the possibility is raised that this phenomenon may be due to modification by smoking of the normal physiological response to stressful stimuli.