Loneliness, Social Isolation, and Community Belonging as Correlates of Psychological Distress Among Men Who Have Sex with Men in Portugal

Loneliness and social isolation are related but distinct experiences, and their relative contributions to mental health among men who have sex with men (MSM) remain insufficiently studied in Portugal. This cross-sectional online survey of 641 cisgender MSM (age 18–74 years; M = 38.51, SD = 12.83) examined associations among loneliness, objective connectivity, interpersonal belonging, LGBTQIA+ community belonging, social-network composition, negative affect, and psychological distress, using the UCLA Loneliness Scale, the Social Isolation Scale, the Depression Anxiety Stress Scales-21, and a short Portuguese Positive and Negative Affect Schedule. LGBTQIA+ community belonging and LGBTQIA+ network representation were assessed with single items. Correlations, multiple regressions, and two moderation models were estimated with heteroscedasticity-consistent standard errors and sensitivity analyses. Loneliness was the strongest independent correlate of psychological distress (β = 0.509, p < 0.001, R2 = 0.353) and negative affect (β = 0.398, p < 0.001, R2 = 0.193). Interpersonal belonging showed a small, borderline inverse association with distress (β = −0.10, p = 0.050) that did not survive covariate adjustment. Neither LGBTQIA+ community belonging nor LGBTQIA+ network representation moderated the loneliness–distress association. Subjective loneliness was more closely tied to distress than objective connectivity or broad community integration. These cross-sectional findings are consistent with the value of examining interventions that address the quality and reciprocity of close relationships alongside affirming community resources.