Measuring the Association Between Cannabis Dispensary Density and Adult Consumption in a Statewide Setting: Does Urbanicity Matter?

Abstract

Objective: This study used data from early stages of non-medical cannabis legalization in Washington State to 1) Compare cannabis dispensary density measures by urbanicity, 2) Test if dispensary density was associated with cannabis use overall and by urbanicity. Method: Data are from the Privatization of Spirits in Washington Surveys (n = 2,162 adults) and licensing records. We graphed six cannabis dispensary density measures by urbanicity. Logistic regressions tested if dispensary density was associated with 1) cannabis use at least bimonthly and 2) daily/near-daily cannabis use after adjusting for urbanicity. Regressions stratified by urbanicity determined whether associations differed in urban vs. suburban/rural areas. Results: Crude counts and counts per population were higher in suburban/rural areas. Counts per land area, counts in a 3- to 5-mile buffer, proximity, and clustering detected greater densities in urban areas. Monthly/bimonthly cannabis use was associated with counts per buffer in the full sample (aOR = 1.08 [1.02, 1.14]) and urban areas (aOR = 1.08 [1.02, 1.14]). Clustering was associated with monthly/bimonthly use in suburban/rural areas (aOR = 7.85 [1.31, 47.17]). Daily/near-daily use was associated with proximity and clustering in the full sample (proximity: aOR = 0.78 [0.64, 0.97]; clustering: aOR = 2.44 [1.32, 4.51]), urban areas (proximity: aOR = 0.67 [0.49, 0.92]; clustering: aOR = 2.29 [1.22, 4.32]), and suburban/rural areas (proximity: aOR = 0.66 [0.45, 0.97]; clustering: aOR = 11.10 [1.55, 79.36]). Conclusions: In Washington’s early non-medical cannabis market, dispensary availability (counts) was associated with monthly/bimonthly use. Accessibility (proximity) and clustering were associated with daily/near-daily use. Dispensary density thresholds and minimum distances between dispensaries may reduce regular and frequent cannabis use in Washington.