Poverty and cumulative hospitalization in infancy and early childhood in the Quebec birth cohort: a puzzling pattern of association.

OBJECTIVE: We anticipate a negative gradient between income and hospitalization, since income is positively associated with good health. In a previous cross-sectional study, we reported an unexpected pattern of association between poverty and hospitalization for 5-month-old infants in Quebec. This study re-examines the poverty-hospitalization relationship within a longitudinal population study of the same birth cohort aged 3.5 years.
METHOD: Life table analysis, multivariable proportional hazard regression, and multivariable logistic regression were performed on data from the first four waves of the Quebec Longitudinal Study of Child Development (QLSCD). Probabilities of hospitalization were estimated by poverty status. The hazard ratios (HR) (Cox-regression) for duration of poverty (frequency of insufficient income) and severity of poverty (combining frequency and level of income insufficiency) were estimated, controlling for predisposing, enabling, and need determinants of hospitalization.
RESULTS: At 3.5 years, 31% of children had been hospitalized at least once. Compared with children whose families had constantly sufficient income, children with intermittent poverty exhibited higher hospitalization risks (HR = 1.30; 95%CI = 1.04-1.64) while chronically poor children exhibited comparable hospitalization hazards (HR = 0.97; 95%CI = 0.73-1.27). Hospitalization risks for children in the severest poverty group resembled that of the non-poor group (HR = 0.99; 95%CI = 0.66-1.49), while children in less severely poor families were more likely to be hospitalized (HR = 1.26; 95%CI = 0.99-1.60).
CONCLUSION: Results suggest hospitalization barriers for children living in chronic and severe poverty. If these barriers exist in a universal health care system, they may originate with primary care service organization or hospital care referral procedures.