Effects of volatile substance abuse on the respiratory system in adolescents

Aim: Inhalant abuse is a prevalent and often overlooked form of substance abuse in adolescents. Chronic inhalant abuse can damage respiratory, cardiac, renal, hepatic, and neurolog- ic systems. This study aims to determine the physiologic effects of inhaling solvents on the respiratory functions. Methods: The general health status of the subjects was assessed by history taking, physical examination and a questionnaire which was designed to show the severity of respiratory symp- toms. Spirometry, ventilation/perfusion scintigraphy, and high resolution computed tomography (HRCT) were performed to assess pulmonary functions and anatomy. Results: Thirty-one male volatile substance abusers and 19 control subjects were included in the study. The mean age of onset of inhalant use was 14.6 ± 2.2 (9-18) years and dura- tion of drug use was 3.7 ± 1.7 years. The most common respi- ratory symptoms in volatile substance abusers were nasal congestion (45.2%), sputum (38.7%), exercise intolerance (32.3%) and cough (22.6%). Results of spirometric studies showed 12 (41.4%) subjects with low FVC values < 80% of predicted, indicative of restrictive ventilatory pattern in the study group. Although the difference was not statistically sig- nificant, restrictive ventilatory pattern was higher in the study group. There was no statistically significant correlation between restrictive ventilatory pattern and the age of onset/duration/frequency of inhalant abuse, respiratory symptoms and scintigraphic abnormalities. Subjects who had restrictive pattern in their pulmonary function tests were more likely to have abnormal findings at HRCT (p < 0.01). Conclusion: This study has shown a positive correlation between volatile substance abuse and the development of restrictive ventilatory pattern, but more comprehensive stud- ies are needed for more precise conclusions.