Comorbidities in patients with gout prior to and following diagnosis: case-control study.
OBJECTIVE
To determine the burden of comorbidities in patients with gout at diagnosis and the risk of developing new comorbidities post diagnosis.


METHODS
There were 39 111 patients with incident gout and 39 111 matched controls identified from the UK Clinical Practice Research Data-link. The risk of comorbidity before (ORs) and after the diagnosis of gout (HRs) were estimated, adjusted for age, sex, diagnosis year, body mass index, smoking and alcohol consumption.


RESULTS
Gout was associated with adjusted ORs (95% CIs) of 1.39 (1.34 to 1.45), 1.89 (1.76 to 2.03) and 2.51 (2.19 to 2.86) for the Charlson index of 1-2, 3-4 and ≥5, respectively. Cardiovascular and genitourinary diseases, in addition to hyperlipidaemia, hypothyroidism, anaemia, psoriasis, chronic pulmonary diseases, osteoarthritis and depression, were associated with a higher risk for gout. Gout was also associated with an adjusted HR (95% CI) of 1.41 (1.34 to 1.48) for having a Charlson index ≥1. Median time to first comorbidity was 43 months in cases and 111 months in controls. Risks for incident comorbidity were higher in cardiovascular, genitourinary, metabolic/endocrine and musculoskeletal diseases, in addition to liver diseases, hemiplegia, depression, anaemia and psoriasis in patients with gout. After additionally adjusting for all comorbidities at diagnosis, gout was associated with a HR (95% CI) for all-cause mortality of 1.13 (1.08 to 1.18; p<0.001).


CONCLUSIONS
The majority of patients with gout have worse pre-existing health status at diagnosis and the risk of incident comorbidity continues to rise following diagnosis. The range of associated comorbidities is broader than previously recognised and merits further evaluation.
Division of Rheumatology, Orthopaedics and Dermatology, School of Medicine, University of Nottingham, Nottingham, UK Division of Rheumatology, Allergy and Immunology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
Chang-Fu
CF
Kuo
Division of Epidemiology and Public Health, School of Medicine, University of Nottingham, Nottingham, UK.
Matthew J
MJ
Grainge
Arthritis Research UK Primary Care Centre, Keele University, Keele, UK.
Christian
C
Mallen
Division of Rheumatology, Orthopaedics and Dermatology, School of Medicine, University of Nottingham, Nottingham, UK.
Weiya
W
Zhang
Division of Rheumatology, Orthopaedics and Dermatology, School of Medicine, University of Nottingham, Nottingham, UK.
Michael
M
Doherty
D000368:Aged; D016022:Case-Control Studies; D015897:Comorbidity; D016208:Databases, Factual; D005260:Female; D005500:Follow-Up Studies; D006073:Gout / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D006113:United Kingdom / Q000453:epidemiology
Cardiovascular Disease; Epidemiology; Gout