Methamphetamine use disorder, perceived impacts, and associated factors among adults receiving care at Sri Lanka’s National Institute of Mental Health: An analytical cross-sectional study

Methamphetamine addiction poses a growing public health challenge in Sri Lanka, yet limited research explores its impacts on the addicted population. This study aimed to assess the severity, patterns, and perceived impacts of methamphetamine addiction among adult patients at the National Institute of Mental Health (NIMH), Angoda, Sri Lanka. An analytical cross-sectional study was conducted among adult clients (aged >18 years) diagnosed with methamphetamine use disorder according to DSM-5 criteria at NIMH, Sri Lanka. A sample of 427 participants was recruited through purposive sampling. Data were collected using a structured, self-developed, validated, interviewer-administered questionnaire covering sociodemographic details, addiction severity (DSM-5 criteria), consumption patterns, impacts, and reasons for use. Descriptive statistics were analyzed using SPSS version 26. All participants (100%) responded to the survey. Among participants, 93.7% were male, and 65.3% were aged 18-30 years. The majority resided in urban (57.9%) or semi-urban (36.1%) areas. Addiction severity was categorized as mild (29%), moderate (38.6%), and severe (32.3%). Most (65.3%) initiated methamphetamine use between 21-30 years. Smoking (52.7%) and snorting (44.9%) were common methods of use, with peer pressure (48.9%) cited as the primary reason for initiation. The most cited physical impacts were weight loss (38.8%) and loss of appetite (37.2%), while irritability (28.8%) and interpersonal relationship problems (50.8%) were cited as common mental and social perceived impacts, respectively. Findings reveal that young urban males are predominantly affected by methamphetamine addiction, with moderate to severe dependence common. methamphetamine addiction severity was associated with living arrangement, monthly income, living area, age of onset, frequency of consumption, method of consumption, and accessibility (p < 0.05). Peer influence and easy accessibility were significant contributing factors. The physical, mental, and social health impacts emphasize the urgent need for comprehensive intervention strategies focusing on prevention, early detection, and integrated rehabilitation services at the national level.