ABSTRACT: This study assessed the association between early onset of smoking and substance abuse with nicotine dependence, the extent of substance abuse, and the probability of relapse. Methods: Self-reported data were collected from 632 patients from 5 drug treatment facilities in the Philippines from July 2019 to September 2019, selected locations into two National Capital Region-Manila, Region VI and VII (Southwestern Tagalog Regions), and XI (partly BARMM-Bangsamoro Autonomous Region in Muslim Mindanao) Davao City Treatment Rehabilitation Center for Drug Dependents. Results: The 5th Edition of the Addiction Severity Index and the Fagerström Test for Nicotine Dependence were used to assess drug and alcohol use and nicotine dependence severity, respectively. The sample consisted of approximately 45.57% non-nicotine-dependent former smokers and 54.43%.
