Concept, Prevalence and Clinical Profile of Adult ADHD with a Special Focus on India: A Systematic Review

Purpose of the Review: Attention-deficit/hyperactivity disorder (ADHD) is increasingly recognized as a neurodevelopmental disorder that persists into adulthood, associated with functional impairments and psychiatric comorbidities. Global estimates range from 2% to 7%, with higher rates reported in low- and middle-income countries (LMICs). In India, where a large proportion of the population is young, understanding the prevalence and clinical profile of adult ADHD is vital for public health. This article aims to summarize the existing evidence on adult ADHD in India, focusing on prevalence patterns, clinical correlates, and methodological challenges. Collection and Analysis of Data: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic review was conducted using PubMed and Google Scholar up to August 2025. Original studies reporting prevalence or clinical features of adult ADHD in India were included, while reviews, case reports, and studies of Indian populations abroad were excluded. Twenty-four studies were identified and synthesized narratively with attention to conceptualization, prevalence, comorbidities, and cultural influences. Conclusions: Prevalence estimates varied across settings. Community and student samples reported rates between 5.5% and 23.3%, with the inattentive subtype consistently dominant. Clinical and substance use disorder (SUD) populations demonstrated higher prevalence, ranging from 18% in opioid-dependent inpatients to 62% in alcohol-dependent cohorts. Comorbidities commonly included depression, anxiety, bipolar disorder, and substance dependence, with ADHD amplifying illness severity and relapse risk. Gender disparities were evident, with women often underdiagnosed due to internalizing presentations. Methodological gaps included reliance on self-report tools, limited retrospective childhood confirmation, and a lack of intervention trials. Adult ADHD in India shows higher prevalence and distinctive cultural influences compared with global estimates. Standardized diagnostic protocols, gender-sensitive approaches, and culturally adapted interventions are urgently needed to improve recognition and care.