Feeling Healthy Matters: Comparing the Moderating Roles of Multimorbidity and Self-Rated Health in the Link Between Loneliness and Quality of Life

Loneliness is a significant psychosocial issue among middle-aged and older adults, negatively impacting quality of life (QoL). However, little is known about how different health measures – specifically objective (multimorbidity) and subjective (self-rated health, SRH) – moderate this association. This study investigates the moderating roles of multimorbidity and SRH in the loneliness-QoL relationship among community-dwelling middle-aged and older adults in Malaysia. This cross-sectional analysis used baseline data from the AGELESS study, involving 1,697 participants aged 55 and above. QoL was measured using the CASP-12 scale, covering control and autonomy, self-realization, and pleasure. Loneliness was assessed using the 3-item UCLA Loneliness Scale. Multimorbidity was defined as having two or more chronic conditions, while SRH was assessed via a single-item question and categorized as “good” or “poor”. Moderation effects were tested using Model 1 of the PROCESS Macro in SPSS (5,000 bootstraps), adjusting for demographics. Loneliness was significantly and negatively associated with total QoL and all three domains. Multimorbidity did not moderate this relationship but was independently linked to poorer QoL. In contrast, SRH significantly moderated the association between loneliness and total QoL, as well as the control and autonomy and self-realization domains. The negative effect of loneliness on QoL was stronger among those reporting “good” health. Contrary to our hypothesis, the negative effect of loneliness on QoL was stronger among those reporting “good” health. Sensitivity analyses using the ordinal SRH scale confirmed these results. Subjective health perception shapes how loneliness affects QoL. Middle-aged and older adults with better SRH may be more vulnerable, underscoring the need for person-centered interventions.