A comprehensive scoping review examining substance use prevention, policies, financing, and treatment across all 22 Pacific Island Countries and Areas has identified stark regional disparities and critical evidence deficits spanning the entire health-system landscape. Covering a combined population of 14.6 million people residing across geographically dispersed island jurisdictions, the investigation mapped publicly available peer-reviewed publications and grey literature to evaluate regional capacity for managing substance use disorders. Despite the disproportionate disease burden linked to psychoactive substances throughout the Pacific—where tobacco use represents the leading contributor to all-cause disability-adjusted life years—researchers discovered that health-system documentation, domestic funding mechanisms, and rigorous intervention assessments remain acutely fragmented, inconsistently collected, or entirely absent across most jurisdictions.
Published in The Lancet Regional Health – Western Pacific, the scoping review evaluated public evidence across four systemic pillars: legislation and national policies, financial investment, service delivery capacity alongside service utilization, and intervention effectiveness. Drawing upon the World Health Organization health system framework to gauge progress toward Universal Health Coverage, the investigative team surveyed both supply-side infrastructure and demand-side barriers. To synthesize available data, researchers systematically probed eight peer-reviewed English databases, including Medline, Embase, PubMed, Web of Science, APA PsycInfo, APA PsycExtra, EconLit, and the WHO Western Pacific Region Index Medicus, alongside two French databases, HAL and Lissa. These were supplemented by exhaustive grey literature searches across platforms such as the PAIS Index, Policy Commons, OECD iLibrary, Overton, and individual ministerial portals, ultimately yielding 407 English-language records comprising 52 peer-reviewed articles and 355 grey literature documents, with zero relevant studies identified in French repositories.
The distribution of identified literature was heavily skewed, reflecting pronounced structural inequities in research capacity and institutional ties. Among the 22 jurisdictions, Guam accounted for the highest concentration of records, with 13 peer-reviewed articles and 97 grey literature documents, whereas the Pitcairn Islands yielded just one peer-reviewed study and four grey literature reports. The vast majority of retrieved materials addressed governance and legislation, totaling 294 publications, while service delivery capacity and utilization accounted for 135 documents. Financial investments were documented in only 59 records, and intervention evaluations were exceptionally sparse, represented by merely seven peer-reviewed publications. The authors observed that Pacific Island Countries and Areas possessing closer institutional and academic connections to the United States, Australia, or New Zealand generated substantially higher research volumes, leaving independent and smaller island systems critically under-documented.
Policy analysis revealed substantial statutory gaps and regulatory inconsistencies across jurisdictions, particularly concerning substances with deep cultural roots. While 14 of the 22 jurisdictions have enacted a national Tobacco Control Act, explicit policies addressing alcohol and culturally embedded substances were absent in many settings. Only five jurisdictions—the Cook Islands, the Federated States of Micronesia, the Marshall Islands, Palau, and New Caledonia—have banned electronic nicotine delivery systems. Betel nut, or betel quid, which carries severe risks of oral cancer and dependence, is regulated under dedicated prohibition legislation in only the Northern Mariana Islands and the Marshall Islands. Similarly, kava, a psychoactive beverage derived from Piper methysticum, is governed by specific statutory acts only in Vanuatu and Kiribati. Regulatory thresholds also diverged markedly: minimum legal purchase ages for tobacco ranged from 18 to 21 years across 16 jurisdictions but lacked any documented restriction in six, while legal purchase ages for alcohol were documented in 15 jurisdictions but absent in seven, including Papua New Guinea and Nauru.
Health financing data further underscored widespread vulnerability and extreme fiscal divergence among the surveyed jurisdictions. Across the 14 island nations with reported data on current health expenditure as a proportion of gross domestic product in 2022, values ranged from 3% in Papua New Guinea to 18% in Nauru. Among the 13 jurisdictions reporting domestic general government health spending, allocations spanned from 2% of total government expenditure in the Federated States of Micronesia to 15% in Samoa, which stood as the sole Pacific jurisdiction to achieve the target set by the Abuja Declaration. High dependency on foreign assistance was prevalent, with eight of 13 reporting nations relying on external aid for at least 20% of their total health expenditure, reaching an extraordinary peak of 77% in Micronesia. Although excise taxes on tobacco and alcohol represent a recognized mechanism for reducing consumption and mobilizing domestic revenue, only three jurisdictions—Palau at 78.1%, Tonga at 72.1%, and the Cook Islands at 70.7%—met the regional target of taxing tobacco at more than 70% of retail price.
Physical infrastructure and specialized workforce capacity for substance use treatment were severely constrained throughout the region. Based on World Health Organization estimates from 2019 for 14 reporting jurisdictions, the average Service Capacity Index for Substance Use Disorders—which quantifies the percentage of theoretical health-system elements available to treat substance use disorders—stood at just 22.54%. Capacity ranged from lows of 6.5% in Vanuatu and 9.3% in the Cook Islands to highs of 31.7% in Tonga and 32.3% in Palau. Crucially, the review identified zero reporting jurisdictions with available data on contact coverage, leaving the actual proportion of individuals with substance use disorders receiving annual clinical treatment completely unmeasured. Furthermore, specialized clinical staff were documented in only nine jurisdictions, revealing systemic deficits such as Guam operating with only 25 certified substance treatment counselors against an identified need of 40, Papua New Guinea maintaining a single tobacco control staff member within its Department of Health in 2018, and Tonga operating a national quit-line staffed by two trained clinicians.
Severe geographic isolation compounds these workforce limitations, erecting massive physical barriers to healthcare access. In archipelagic nations like the Federated States of Micronesia, which encompasses 607 islands, inpatient substance use treatment is concentrated in a hospital situated on a single island, requiring inter-island travel by boat or airplane. Similarly, the Marshall Islands concentrates its secondary substance use care across two islands, Majuro and Ebeye, effectively isolating residents across the remaining 22 populated atolls. In response to infrastructural bottlenecks, several jurisdictions have integrated cessation services into general chronic disease infrastructure; Fiji, for instance, established five dedicated tobacco cessation centers and embedded services into diabetes and adolescent reproductive clinics, while training more than 500 non-specialist clinicians via the WHO Mental Health Gap Action Programme. However, long-term monitoring and follow-up data regarding the retention and clinical efficacy of these training initiatives remain virtually undocumented.
Direct empirical evidence evaluating the real-world effectiveness of substance use interventions was extraordinarily limited, comprising just six unique interventions assessed across seven publications. Of these, four interventions targeted adults over age 16, while two evaluated adolescent school cohorts. Methodological designs were predominantly preliminary: four were pilot studies conducted in the Cook Islands, Guam, Papua New Guinea, and Samoa, one was a qualitative cross-sectional investigation of broadcast media spots in Samoa, and one was a pilot stratified cluster randomized trial in Guam. Only a single full-scale randomized clinical trial was identified: the Betel Nut Intervention Trial conducted in Guam and the Northern Mariana Islands. This community-based trial demonstrated that an intensive cognitive-behavioral intervention consisting of five sessions over 22 days achieved an areca nut cessation rate of 38.6%, compared to 9.1% among control participants who received only educational brochures.
Remarkably, the scoping review identified an absolute absence of cost-effectiveness evaluations across all 22 Pacific jurisdictions, as well as a complete lack of formal intervention trials targeting alcohol or illicit drug use disorders. This represents a glaring epidemiological contradiction, given that alcohol-attributable mortality through liver cirrhosis, noncommunicable diseases, and road trauma remains elevated across the Pacific, while intravenous drug transmission has been tied directly to rising burdens of HIV and other sexually transmitted infections. The authors emphasized that the existing literature disproportionately captures pilot feasibility and self-reported risk perception rather than verified clinical outcomes, with intervention research further constrained by the broader underrepresentation of Pacific Islander populations in published biomedical literature.
The authors noted important methodological limitations inherent to the scoping review design, including the absence of formal quality appraisals or risk-of-bias scoring for the included studies, meaning that rigorous clinical trials and unverified grey literature reports were evaluated on equal evidentiary terms. Furthermore, unrecorded grassroots, community-based, or traditional healing initiatives operating without published documentation could not be captured. To overcome these persistent health-system barriers, the review underscores the necessity of establishing standardized regional surveillance mechanisms, establishing hypothecated excise taxes to guarantee dedicated health budgets, integrating substance use screening into decentralized primary care and telehealth networks, and conducting culturally grounded, randomized intervention trials tailored to the distinct sociocultural environments of the Pacific Islands.
Subject of Research: Scoping review of health-system policies, financing, and treatment capacity for substance use across Pacific Island Countries and Areas
Article Title: Policies, resource allocation, and interventions for substance use in the Pacific Island Countries/areas: a scoping review
Article References: Chu, L., Balkian, J., Giovannucci, I., Zhang, S., Mui, C., Ayele, S., Tuan, J. Z., Tran, S., Raghavan, D. P., Gabbidon, J., Charpignon, M.-L., Crookes, A., Nadkarni, A., & Lu, C. (2026). Policies, resource allocation, and interventions for substance use in the Pacific Island Countries/areas: a scoping review. The Lancet Regional Health – Western Pacific, 76, Article 102015. https://doi.org/10.1016/j.lanwpc.2026.102015
Image Credits: AI Generated
DOI: 10.1016/j.lanwpc.2026.102015
Keywords: Pacific Island Countries and Areas, substance use, scoping review, health systems, universal health coverage, tobacco control, alcohol regulation, betel nut, kava, health financing, service delivery capacity, mental health, public health policy, WHO mhGAP, harm reduction, clinical trials
