Socioeconomic inequalities in health-related functioning among people with Type 2 Diabetes

BACKGROUND: Type 2 Diabetes mellitus (T2DM) is a common chronic disease which disproportionally affects disadvantaged groups. People with a low socioeconomic position (SEP) have increased risk of T2DM and people with a low SEP and T2DM have higher HbA1c levels and a higher risk to develop T2DM complications compared to their high SEP counterparts. The aim of this study is to analyze longitudinal socioeconomic differences in health-related functioning in people living with T2DM. METHODS: Cross-sectional and longitudinal data from 2,004 participants of The Maastricht Study with T2DM were used. SEP was determined by baseline measures of education, occupation and income. Health-related functioning (physical, mental and social) was measured with the SF-36 and the Impact on Participation and Autonomy survey (scores 0-100). Associations of SEP and health-related functioning were studied over a 10-year period (baseline 2010-2018) using linear mixed methods adjusting for demographics, disease characteristics and lifestyle factors. RESULTS: Low SEP participants had significantly worse health-related functioning compared to those with a high SEP. For example, participants with low income had lower scores for physical (-4.00[CI 2.62;-5.38]), mental (-2.81[-1.52;-4.10]) and social functioning (-9.10[-6.35;-11.85]) compared to high-income participants. In addition, participants with a low education significantly declined more in mental (interaction estimate time -0.21[-0.05;-0.37]) and social functioning (-0.39[-0.02;-0.76]) compared to participants with high education. CONCLUSIONS: In individuals with T2DM, socioeconomic health differences are apparent in health-related functioning. Moreover, differences in mental and social functioning widened even more between different levels of education. Beyond disease characteristics and lifestyle, more attention is needed for socioeconomic differences in health-related functioning for people living with T2DM, both in research and practice. KEY MESSAGES: • Among people with T2DM, those with a lower SEP have worse health-related function then individuals with a higher SEP, even with similar demographics, disease characteristics and lifestyle patterns. • Additionally, people with T2DM and low education decline more over time in mental and social functioning than people with T2DM and high education.