Impact of Poverty and Sickle Cell Disease on the Health-Related Quality of Life of Children.

Abstract

Previous studies have shown that poverty is associated with worse health-related quality of life (HRQL). Children with sickle cell disease have been shown to have poor HRQL. The impact that poverty and sickle cell disease have on the HRQL of children has not been well delineated. The objective of this study was to determine the impact of poverty and sickle cell disease on the HRQL of children with and without sickle cell disease. A cross-sectional study was conducted. Parents of children with sickle cell disease and parents of children without sickle cell disease (controls) who presented to the clinic (ages 2 to 18 years) were asked to complete the PedsQL questionnaire. Detailed demographic information on total family income and family size was collected to classify family income based on the federal poverty threshold. The primary outcome measured was HRQL. An impaired HRQL, a score similar to that of children with chronic disease, is defined as any score that is less than the population mean -1 standard deviation (Varni, et al. 2003). Three HRQL summary scores were assessed: total, physical and psychosocial summary scores. Poverty level and sickle cell disease were the independent variables of interest. Descriptive statistics and non-parametric tests were used to look for significant differences. An ordinal multinomial regression model was used to look at the independent effects of income and disease on the HRQL of children. A total of 104 children with sickle cell disease and 74 control patients participated in the study. Approximately half of the study population was female, 98% of the cases and 78% of the controls were African-American. Approximately half (58%) of the controls and 42% of the cases with sickle cell disease had a family income at poor or near poor (100% or 100–124% of the federal poverty threshold). There were 15% of the controls and 25% of the cases that had a low family income (125–200% of the federal poverty threshold). The remainder in each group were considered as middle/high income (greater than 200% of the federal poverty threshold). The median HRQL was significantly worse in the children with sickle cell disease compared to the control group in all summary scores, p < 0.05 adjusted for multiple comparisons (total score 67.4 versus 80.7, physical summary score 68.8 versus 87.5, psychosocial summary score 68.1 versus 75.0). When both disease and family income were examined in the regression model, children who were poor and who had sickle cell disease were more likely to have lower physical and psychosocial HRQL. Children with sickle cell disease were more than twice as likely to have an impaired physical HRQL compared to controls at each family income level. (Table 1). In conclusion, children with sickle cell disease have an increased probability of having impaired physical HRQL compared to children without sickle cell disease across each family income level.Predicted Probabilities of Poor Physical Health Score (PHS) (based on multinomial regression model)GroupIncome LevelPr (PHS ≥ 63.28)*95% Confidence IntervalControlPoor/Near Poor0.230.14–0.36Low0.240.12–0.41Middle/High0.100.04–0.22Sickle Cell DiseasePoor/Near Poor0.490.37–0.61Low0.490.34–0.64Middle/High0.260.14–0.42*Denotes probability that PHS is≤ 1 standard deviation below the population mean reported by Varni et al. 2003