Background Gout was previously regarded a disease of the affluent. Knowledge about the association between gout and socioeconomic status in modern times is limited.
Objectives To investigate the association between gout and socioeconomic factors in a population based register study in a large region in Sweden.
Methods All patients receiving ≥2 diagnoses of gout on at least two separate occasions in primary or secondary care or 1 diagnosis by a specialist in Rheumatology in Västra Götaland in the years 2007–2012 were identified by ICD10 codes in a regional database of health-care utilization. 3189 such patients were identified. The date of the first diagnosis was defined as the index date. A previous validation study of cases identified in this manner confirmed that this case definition is highly consistent with a diagnosis of gout as defined by established criteria (PPV >80%)(1).
For each case, up to 5 controls matched for age, gender and place of residence at the time of the first gout diagnosis were chosen by the Statistics Sweden agency (SCB) (N=14946).
Common comorbidities known to be associated with gout (ischemic heart disease, heart failure, atrial fibrillation, hypertension, hyperlipidemia, diabetes and renal failure) prior to the index date were retrieved from the regional database of health-care utilization based on ICD10-codes.
Data on education level and income at the index year was collected from the Longitudinal Integration Database for health Insurance and Labor market studies (LISA). The database holds annual registers since 1990 on all individuals above 16 years of age registered in Sweden.
Results Data on education level and income was analyzed for cases and controls belonging to the working-age population as defined in Sweden (aged 15–74 years). Shorter education, <12 years, was significantly more common among cases. Yearly income was lower among cases irrespective of educational length (Table 1). Cases had significantly more pre-index comorbidities compared to the controls. In a subgroup analysis of 1084 cases and 6117 controls of working age without any cardiovascular- or renal comorbidity, educational level and income was still significantly lower among cases (data not shown).
Conclusions Low education level and income are predictors for gout in the working age population. The effects of education do not seem to be largely/only mediated via cardiovascular- or renal comorbidity, supporting that other factors possibly related to lifestyle or occupational exposures are of importance for gout development.
Dehlin M, Stasinopoulou K, Jacobsson L. Validity of gout diagnosis in Swedish primary and secondary care – a validation study. BMC Musculoskelet Disord. 2015;16:149.
Disclosure of Interest None declared