Deprivation and cause specific morbidity: evidence from the Somerset and Avon survey of health.

OBJECTIVE

To investigate the association between cause specific morbidity and deprivation in order to inform the debates on inequalities in health and health services resource allocation.

DESIGN

Cross sectional postal questionnaire survey ascertaining self reported health status, with validation of a 20% sample through general practitioner and hospital records.

SETTING

Inner city, urban, and rural areas of Avon and Somerset.

SUBJECTS

Stratified random sample of 28,080 people aged 35 and over from 40 general practices.

MAIN OUTCOME MEASURES

Age and sex standardised prevalence of various diseases; Townsend deprivation scores were assigned by linking postcodes to enumeration districts. Relative indices of inequality were calculated to estimate the magnitude of the association between socioeconomic position and morbidity.

RESULTS

The response rate was 85.3%. The prevalence of most of the conditions rose with increasing material deprivation. The relative index of inequalilty, for both sexes combined, was greater than 1 for all conditions except diabetes. The conditions most strongly associated with deprivation were diabetic eye disease (relative index of inequality 3.21; 95% confidence interval 1.84 to 5.59), emphysema (2.72; 1.67 to 4.43) and bronchitis (2.27; 1.92 to 2.68). The relative index of inequality was significantly higher in women for asthma (P < 0.05) and in men for depression (P < 0.01). The mean reporting of prevalent conditions was 1.07 for the most deprived fifth of respondents and 0.77 in the most affluent fifth (P < 0.001).

CONCLUSIONS

Material deprivation is strongly linked with many common diseases. NHS resource allocation should be modified to reflect such morbidity differentials.