Do changes in income and social networks influence self-rated oral health trajectories among civil servants in Brazil? Evidence from the longitudinal Pró-Saúde study

Abstract

Abstract Background Social factors are important determinants of health. However, evidence from longitudinal studies on the possible role of changes in socioeconomic circumstances on adult’s oral health is scarce. This study aimed to test whether changes in income and changes in social networks of family members and friends were associated with trajectories of self-rated oral health (SROH) among adults over a 13-year period. Methods A prospective cohort study (Pro-Saude Study) was conducted involving non-faculty civil servants at university campi in Rio de Janeiro, Brazil. Individual data was collected through self-completed questionnaires in four waves (1999, 2001, 2007 and 2012). SROH trajectories between 2001 and 2012 were “Good-stable SROH”, “Changed SROH”, “Poor-stable SROH”. Per capita family income and social networks of family members and friends data obtained in 1999 and 2012 were grouped into “High stable”, “Increase”, “Decrease”, “Low stable”. Ordinal logistic regression using complete data of 2118 participants was used to estimate odds ratio (OR) and 95% CIs of changes in income and changes in social networks with SROH trajectories, adjusted for age, sex, skin colour and marital status. Results Participants in the low income-stable and small social networks-stable groups showed 2.44 (95% CI 1.68–3.55) and 1.98 (95% CI 1.38–2.85) higher odds for worst trajectory of SRHO than those in the respective high-stable groups. Those in the decrease income group and decrease social networks group were 78% (95% CI 1.25–2.54) and 58% (95% CI 1.07–2.34) more likely to worst trajectory of SRHO than those in the high income-stable and high social networks-stable groups. Conclusions Adults reporting low income and low social networks of family members and friends over 13 years and those with income and social networks decrease during the study period were at higher risk of having worsened their self-rated oral health.