Population aging is a global phenomenon driven by declining birth rates and increased life expectancy, presenting significant societal challenges. Adapting policies, economies, and healthcare systems is crucial to ensure the well-being of older adults. Health inequalities, significantly influenced by social determinants of health (SDHs) such as education, economic status, and place of residence, disproportionately affect this population, with marked differences between men and women. Women often report lower QoL indicators, lower educational attainment, and poorer overall health compared to men. This study hypothesizes that SDHs, including age, education, economic status, immigration status, and place of residence, will significantly influence QoL evolution in individuals over 50, with variations based on sex and European region. The objective is to analyze the longitudinal influence of these SDHs on QoL in a diverse European population, stratified by sex and region.

Existing research demonstrates a strong link between SDHs and QoL in older adults, particularly women. Studies highlight the negative impacts of factors like limited economic resources, advanced age, and gender on QoL. The multidimensional nature of QoL, encompassing both objective and subjective aspects, is widely acknowledged. While research explores the influence of objective health factors (multimorbidity, chronic diseases, functional limitations, depression) on QoL, less attention has been given to a comprehensive, longitudinal analysis across diverse European regions, comparing the experiences of men and women. Prior studies in Spain examined family trajectories' influence on QoL, revealing sex-specific impacts of social relationships and partnership status. However, a comparative analysis across various European regions, with a focus on men and women's differentiated experiences, is lacking.

This population-based, analytical, prospective cohort study utilized data from waves 5, 6, and 7 of the Survey of Health, Ageing and Retirement in Europe (SHARE) study (2013, 2015, and 2017). The SHARE study employs standardized fieldwork procedures across 13 European countries (Germany, Austria, Belgium, Denmark, Slovenia, Spain, Estonia, France, Italy, Luxembourg, Sweden, Switzerland, and the Czech Republic), minimizing bias in cross-country comparisons. Data collection involved computer-assisted personal interviews (CAPI) conducted at participants' homes. The study included 11,493 individuals aged 50 or older who participated in all three waves. To address potential selection bias observed in Wave 5, a matching algorithm was implemented to pair participants with non-participants of similar age, sex, and region, using the CASP-12 score (Control, Autonomy, Satisfaction, and Self-Realization) as a proxy for QoL. Countries were grouped into four regional clusters based on social welfare models (Northern, Continental, Southern, and Eastern Europe). The outcome variable, QoL, was measured using the CASP-12 scale. Explanatory variables included sex, age group (50-64, 65-74, 75-84, >85), education level (low, medium, high), economic level (difficulty/no difficulty), immigrant status, and place of residence (urban/rural). Covariates included sociodemographic and clinical variables (marital status, employment status, family composition, number of children/grandchildren, self-perceived health, chronic diseases, mobility difficulties, physical activity, depression (EURO-D scale), BMI, smoking, and alcohol consumption). Statistical analysis employed weighted samples to minimize selection bias, using chi-square tests, Student's t-tests, linear mixed-effects models, and smoothing spline regression. The maximum gVIF of 1.22 indicated no multicollinearity issues.

Baseline differences between men and women were observed in various SDHs. Women had an average age of 63.3 years (SD 10.2), while men averaged 64.4 years (SD 9.4). A higher proportion of women had low education levels (37.0% vs. 32.9%) and experienced economic difficulties (30.5% vs. 26.7%). Significant sex differences were also noted in sociodemographic and clinical variables. More women were widowed, lived alone, reported poorer self-perceived health, experienced mobility difficulties, and were physically inactive compared to men. Tobacco and alcohol consumption were significantly higher among men. Women displayed a higher prevalence of depression (30.3% vs. 17.5%). Regional differences were also evident. The Southern region had the oldest population, the highest percentage of women with low education, and the highest rates of economic hardship, particularly among women. The Northern region had the lowest percentages in these categories and a higher percentage of non-native residents. In Wave 5, women in the Southern region had the lowest QoL scores (35.0, SD 6.55) compared to women in the Northern region (40.7, SD 5.17). Men consistently scored higher than women across all regions. QoL scores decreased with age in both sexes. Women in the Southern region with low education had the lowest QoL scores. Economic hardship significantly lowered QoL scores, especially among women in Southern and Eastern Europe. Native individuals had higher QoL scores than immigrants. Living with a partner was associated with better QoL for both sexes, with larger differences observed between women and men in the Southern region. Poor self-perceived health was associated with significantly lower QoL scores. Moderate alcohol consumption was linked to higher QoL scores. Depression was associated with reduced QoL scores in both sexes. Longitudinal analysis (Waves 5-7) revealed a significant decline in QoL scores for both men and women, with a steeper decline for women. The negative impact of age on QoL was more pronounced in women. Higher education levels were associated with higher QoL scores, with the effect being more pronounced in women. Economic hardship significantly negatively impacted QoL, and needing external financial assistance worsened QoL. Living in a rural area had a protective effect on QoL for women but not men. Multivariate analysis revealed significant sex differences in QoL across regions and age groups, with the largest disparities observed in the Southern region. A significant interaction effect was observed between sex, region, and age group.

The findings confirm the significant influence of SDHs on QoL in older adults, highlighting substantial sex-based differences and regional variations. Women experience a greater decline in QoL over time, particularly in Southern Europe, consistent with other SHARE cohort studies. Economic hardship has a considerable negative impact, particularly in Southern and Eastern Europe, reflecting differences in social welfare systems. Lower education levels correlate with reduced QoL, especially among women in Southern Europe. Regional variations reflect diverse social welfare systems, aligning with other research. While some studies suggest a negative association between rural residence and QoL, this study found a protective effect for women in rural areas. The significant impact of depression emphasizes the need for mental health interventions. Lifestyle factors, particularly physical activity for women, show a strong connection to QoL. These results underscore the complex interplay between individual-level factors, social context, and regional disparities in shaping the experiences of older adults.

This study reveals significant sex-based inequalities in QoL among older Europeans, influenced by SDHs and regional variations in social welfare systems. Women consistently report lower QoL scores than men, with the greatest disparities found in Southern Europe. Key SDHs impacting QoL include age, economic hardship, education level, and geographic location. Future research should examine the intersectionality of SDHs and implement targeted interventions to reduce health inequalities, particularly among women in less advantaged regions. Addressing economic insecurity, improving educational opportunities, promoting mental health, and encouraging physical activity are vital strategies for enhancing QoL among older adults.

Several limitations should be considered. Participant attrition between waves might limit the generalizability of findings. Although a matching algorithm was used, the sample might not fully represent the entire population. The measure of economic hardship relied on self-reported data, potentially introducing bias. The study did not consider ethnicity or race, only nativity to the interview country, limiting the understanding of potential cultural impacts on QoL. Furthermore, the use of the "making ends meet" variable to assess economic level might be less precise than income-based measures. Future research incorporating a broader range of SDHs and more nuanced economic indicators would strengthen these findings.