The aging population in Europe, particularly the increasing number of older adults living alone, especially women, necessitates research into the impact of social relationships on their well-being. In Spain, this trend is significant, with a substantial proportion of older adults, particularly women, living alone. Existing research largely focuses on the negative consequences of loneliness, such as health problems and cognitive decline. However, there's a growing need to explore the positive psychological aspects, including life satisfaction, well-being, and happiness, and identify protective factors. This study aims to analyze the relationship between living arrangements (alone or with relatives) and the well-being and happiness of older adults, controlling for sociodemographic variables. Previous research suggests a negative correlation between living alone and well-being, but also highlights other factors such as self-perceived health, autonomy, social support, and leisure activities, that significantly influence the well-being and happiness of older adults. The current study builds upon this research to determine the relative contributions of living arrangements and other psychosocial factors on the well-being and happiness of older adults.

Extensive literature highlights the negative impact of loneliness and social isolation on the health and cognitive function of older adults living alone. Studies consistently show a reduction in autonomy and an increase in age-associated chronic diseases among socially isolated individuals. However, a growing body of research emphasizes the need to investigate the relationship between living alone and positive psychological dimensions, such as life satisfaction, well-being, and happiness. Some studies show a link between living alone and poorer well-being and happiness, suggesting that living with others contributes to maintaining these positive aspects throughout the aging process. However, the literature also notes the influence of factors beyond living arrangements, such as self-perceived health status, autonomy in daily living, and the quality of social relationships and environmental quality. Self-perceived health, in particular, has been shown to significantly influence well-being and happiness in older adults. Further, the frequency of social interaction, particularly with family and friends, is identified as a major predictor of well-being and happiness. Leisure activities are also strongly associated with well-being and happiness in older adults. In short, the review suggests that while living arrangements may play a role, other factors are critical in determining the well-being and happiness of older adults.

This study employed a cross-sectional design, recruiting 352 participants (50.6% women, 49.4% men) aged 65 and older from senior centers in Seville, Spain. Participants were selected intentionally through agreements with the senior centers, with informed consent obtained from all participants. The study was approved by the University Ethics Committee. Data collection, using standardized questionnaires, occurred over six weeks. Three instruments were used: 1. **Brief Quality of Life Questionnaire (CUBRECAVI):** This multidimensional questionnaire assesses quality of life across various domains, including health (subjective, objective, psychological), social integration, functional abilities, activity and leisure, environmental quality, life satisfaction, income, and access to social and health services. The reliability of the scales ranged from α = 0.510 to α = 0.861. 2. **Satisfaction with Life Scale (SWLS):** This instrument measures overall life satisfaction using a seven-point Likert scale (α = 0.812). 3. **Oxford Happiness Questionnaire (OHQ):** This scale measures happiness using a 29-item Likert scale (α = 0.804). Questionnaires were administered in small groups (8 participants) to ensure comprehension and avoid fatigue. The data analysis involved descriptive statistics, multivariate analysis of variance (MANOVA), Pearson correlation analysis, and hierarchical multiple regression analysis, using SPSS version 23. The MANOVA assessed differences based on sex and cohabitation type, controlling for age. Pearson correlations examined the associations between different scales, and hierarchical multiple regression analyzed predictors of well-being and happiness. Multicollinearity was assessed using variance inflation factor (VIF).

The study revealed statistically significant differences in various variables based on cohabitation type and sex. Older adults living alone were found to be significantly older, have lower educational levels, and lower average monthly incomes compared to those living with relatives. Multivariate analysis of variance (MANOVA) revealed that individuals living with relatives had significantly higher levels of social integration, functional skills, well-being (life satisfaction), and happiness than those living alone. There was a significant interaction effect between sex and cohabitation type on health and activity levels. Specifically, women living with family members had better health than women living alone, while men living alone reported better health than men living with family members. In terms of activity levels, women living with family members reported higher levels than women living alone. Further analysis, using Pearson correlations, indicated that age was negatively associated with leisure activities, social integration, health, functional skills, and activity level. Health was positively correlated with functional skills, leisure activities, social integration, and activity level. Leisure activities were positively associated with functional abilities, social integration, and activity level. Well-being and happiness demonstrated positive correlations with most other variables, with happiness having an inverse correlation with age. A strong positive correlation was observed between well-being and happiness. Hierarchical multiple regression analysis showed that, in predicting well-being, cohabitation type was a significant predictor in the first step of the model. After including other psychosocial variables (health, social integration, activity level, leisure, functional skills, and environmental quality), age, health, social integration, leisure activities, and environmental quality were significant predictors. In predicting happiness, cohabitation type and age were significant predictors in the first step. After including other psychosocial variables, health, social integration, and activity level emerged as significant predictors.

The findings support the initial hypothesis that cohabitation with relatives is associated with higher life satisfaction and happiness in older adults. This aligns with previous research demonstrating a link between living with others and enhanced well-being. The observed sociodemographic profile of older adults living alone—higher age, lower education, and lower income—suggests potential socioeconomic disadvantages that may contribute to poorer health and reduced quality of life. The study's main finding highlights the significant influence of social relationships and activity levels on well-being and happiness, independent of living arrangements. Even those living alone who maintain high levels of social integration, participate in social activities, and have strong support networks can maintain high levels of health, well-being, and happiness. The strong correlations between the study variables underscore the interconnectedness of health, autonomy, social interaction, and environmental quality in influencing well-being and happiness. The positive relationship between leisure activities, especially those involving social interaction, and well-being reinforces the significance of social participation. The current research shows that while living with relatives is beneficial for well-being, social support and activity levels are powerful determinants of happiness and well-being, irrespective of the living situation.

This study confirms the significant positive impact of living with relatives on the well-being and happiness of older adults. However, it also reveals that social engagement and participation in activities are powerful determinants of positive mental health, regardless of living arrangements. The findings underscore the importance of public policies focused on social programs and activities that promote social interaction and engagement to improve the well-being of older adults, particularly those living alone. Future research should explore causal relationships through longitudinal studies and experimentally investigate the effect of social participation interventions on well-being and happiness in older adults.

The cross-sectional design of this study limits causal interpretations. The findings only demonstrate associations between variables, not cause-and-effect relationships. The lack of longitudinal data prevents analysis of how the measured indicators may change over time. The intentional sampling method may limit the generalizability of the findings to other populations. Future research would benefit from a more heterogeneous sample and longitudinal data to establish causal links.