257 Assessing the association between experienced and anticipated discrimination with objective physical activity among SGM adults using an unsupervised machine learning approach

Objectives/Goals: Using k-means clustering, we aimed to identify whether clusters characterized by greater exposure to minority stressors (e.g., experienced/anticipated discrimination) were associated with lower moderate-vigorous physical activity (MVPA) and higher sedentary behavior among sexual and gender minority (SGM; e.g., lesbian/gay, bisexual, transgender) adults. Methods/Study Population: SGM adults face higher risks of inadequate PA due to exposure to minority stressors, which may influence their willingness and ability to engage in PA. An online sample of SGM adults completed daily surveys about experienced and anticipated discrimination and wore wrist accelerometers for 28 days to objectively measure PA. We used k-means clustering to identify clusters based on reports of experienced and anticipated discrimination. We determined the optimal number of clusters using established partition criteria and ran linear regression models (adjusted for demographic factors) to examine the associations of minority stress clusters with MVPA and sedentary time. Results/Anticipated Results: Among 42 SGM adults (mean age 27.0±7.7 years) with 1133 person-days of accelerometry data, we identified four minority stress clusters: low anticipated/low experienced (LALE; reference group), low anticipated/high experienced (LAHE); high anticipated/low experienced (HALE), and high anticipated/high experienced discrimination (HAHE). Participants in the HALE cluster (n = 12) engaged in 202 fewer minutes of MVPA than those in the LALE cluster (n = 7). Participants in the LAHE cluster (n = 10) had 123 fewer minutes of vigorous PA than those in the LALE cluster. No differences were identified for sedentary time. Discussion/Significance of Impact: This is the first study to examine the association of minority stressors with objective PA among SGM adults. Participants in the HALE/LAHE clusters had lower PA than those with low levels of experienced and anticipated discrimination. Interventions to improve PA among SGM adults must target reduction of minority stressors.