Aim The relationship between social class and ADHD is unclear. We sought to investigate possible effects of social deprivation on ADHD prevalence in Liverpool area.
Method 1069 children from all areas of Liverpool in the North West region of England diagnosed with ADHD based on DSM-IV standards were studied. The coefficients (Spearman's) of correlation between prevalence rates in each lower superior output areas (LSOA) their corresponding IMD2007 scores or rank were calculated. Each of the 32 482 LSOAs in England with an assigned IMD2007 score and rank were grouped into consecutive groups of 10 centile scores and groups of 1000 ranking bands.
Results The prevalence of ADHD in Liverpool children up to the age of 16 years is 9.91/1000 with a male preponderance (1:6). The prevalence of ADHD patients in each LSOA bands was negatively correlated with the IMD2007 rank. Spearman's correlation (rs) and probability (statistical significance) were −0.9395 and 0.000 respectively. The prevalence of ADHD was also positively correlated with the IMD2007 score bands of their residential postcodes (rs=−0.400827), but this did not reach a statistical level of significance (p=0.097). The ADHD prevalence in each major postcode area (eg, L1, L2 etc.) was also significantly correlated with their average IMD2007 scores (rs=0.494112, p=0.0026). This was also significantly correlated with their average IMD2007 ranking (rs=−0.49291 p=0.0028).
Conclusion The prevalence of ADHD in a relatively deprived city of England appears to be associated with the degree of the socio-economic deprivation of their residential areas. This study suggests that an improved socio-economic environment may significantly improve the overall outcome of childhood ADHD.
The polynomial fitting curve between the LSOA rank orders and the prevalence of ADHD suggests that this might be a useful tool for NHS service commissioners, to predict the expected prevalence of ADHD in their local authorities for future planning (figure 1).