ANXIETY AND DEPRESSION COMORBIDITY IN PRIMARY CARE GOUT: A MATCHED RETROSPECTIVE COHORT STUDY

Background: Chronic conditions such as diabetes mellitus and cardiovascular disease are common in people with gout and are associated with poorer quality of life and higher mortality. However, our understanding of the role of psychological comorbidity in gout remains unclear. Frequent experience of severe pain, social isolation and strained family relationships may impact negatively on psychological health and influence health-seeking behaviour. This matched retrospective cohort study aimed to examine the association between gout and subsequent consultation for anxiety & depression in a UK primary care population. Methods: The study was undertaken using data from a general practice consultation database (CiPCA), gathered from nine general practices in North Staffordshire. Patients aged 18 years who consulted with gout between 2000 and 2008 were identified by Read code and each matched to 4 controls by age, gender, year of consultation and general practice. A consultation for either anxiety or depression, subsequent to the gout diagnosis, was defined from a relevant Read code gained between 2000 and 2011. Several other gout-related comorbidities (e.g. hypertension) were also recorded by Read code. Cox regression model was used to examine the association between gout and subsequent anxiety & depression consultation (new episodes), adjusting for age, gender, deprivation, year of consultation, general practice and comorbidities. Hazard ratio (HR) and 95% CI were reported for gout cases vs matched controls. Results: 1689 patients with gout were compared with 6,756 control patients. Mean age was 63 years (Standard deviation 16) and 24% were female. Of gout patients, 15.3% & 9.7% had consulted for anxiety & depression respectively, this was in comparison with 14.2% & 9.5% of the controls. Adjusted cox regression analysis found no association between gout and time to consultation for anxiety (HR 1.04, 95% CI 0.9, 1.2) or depression [0.88 (0.7, 1.1)] compared with controls. Across gout patients and matched controls, being younger and female was associated with a propensity to consult for anxiety & depression. With each year from first diagnosis (gout and controls), there was a trend of increasing consultation for anxiety. The presence of hypertension and alcoholism comorbidity was associated with an increased probability of consultation for anxiety & depression. Conclusion: Despite the psychological burden which gout may be expected to impart on patients, time to consultation for anxiety & depression in UK primary care was equivalent to matched controls. This may relate to the prolonged asymptomatic inter-critical period between gout attacks during which psychological burden may ease. However, as under-reporting of both anxiety & depression in primary care is common and the severity & disease characteristics of gout, anxiety & depression could not be established from medical records, further research considering these factors would be of benefit. Disclosure statement: The authors have declared no conflicts of interest.