Trends in physician diagnosed gout and gout therapies in the US: results from the national ambulatory health care surveys 1993 to 2009

Table 2 Comparison of pharmacoepidemiology surveys of gout in ambulatory care settings

Author (year), country	Data source	Hospital-based clinics included?	Specialist visits included?	Calendar years of observation	Case definition of gout	Number of gout cases/visits/episodes	Proportion of patients (%)^a
							Allopurinol	Colchicine	Any NSAID	Systemic steroids
Primatesta (2011), US	1	No	Yes	1996 to 2008	ICD codes and gout medication prescription	177,637	36	18	43	20
Reidel (2010), US	1	No	Yes	1997 to 1998	ICD codes and gout medication prescription	9,595	66	15	NA	NA
Roddy (2010), UK	2	No	No	2001 to 2004	Proprietary diagnosis odes	673	23	15	73	0
Annemans (2008), UK	2	No	No	2000 to 2005	ICD codes and/or medical record text mentions of gout, and prescription	34,071	89	16	89	26
Annemans (2008), UK	2	No	No	2000 to 2005	ICD codes and/or medical record text mentions of gout, and prescription	34,797	93	15	80	14
Harris (1995), UK	3	No	No	1993	General practitioner diagnosis	2,865	46	NA	NA	NA
Mikuls (2005), UK	2	No	No	1990 to 1999	Proprietary diagnosis codes	63,105	25 to 30	1 to 3	40 to 66	5%
Cea Soriano (2011), UK	2	No	No	2000 to 2007	Proprietary diagnosis codes	24,768	28	14	19	NA
Krishnan (2005), US	4	No	Yes	2002	ICD codes and prescriptions	206^a	69	4.6	18	6.9
Present study, US^c	4	Yes	Yes	1993 to 2009	ICD codes alone	100.4 million (1,634^b)	35	15	34	10
Present study, US^c	4	Yes	Yes	1993 to 2009	ICD codes and/or prescriptions	35.9 million (4,781^b)	69	17	23	6.8

Settings type 1) Medical and pharmacy insurance claims; 2) General Practice case records with linked pharmacy records; 3) Survey of General practitioners; 4) Nationally representative sample survey of all ambulatory care visits including hospital clinics. ^aWeighted proportions; ^bUnweighted number of observations in the dataset; ^cCumulative, over the study period. NSAID, non-steroidal anti-inflammatory drugs; NA, not available.