Prevalence of long-term oral glucocorticoid prescriptions in the UK over the past 20 years

Objective. To assess trends in long-term (i.e. >= 3 months) oral glucocorticoid ( GC) prescriptions over the past 20 years. Methods. Data of UK adult patients registered between January 1989 and December 2008 with general practices contributing to The Health Improvement Network (THIN) database were obtained. The annual prevalence of long-term oral GC prescriptions was assessed in the whole population and specifically in people with RA, PMR/GCA, asthma, chronic obstructive pulmonary disease (COPD), Crohn's disease and ulcerative colitis (UC). Trends over the 20-year period were estimated using sex- and age-adjusted Poisson regression models. Results. During the 26 035 154 person-years of follow-up, an average of 0.75% (95% CI 0.74, 0.75) of the study population was prescribed long-term oral GC therapy at any time point. This rose from 0.59% (0.52, 0.67) in 1989 to 0.79% (0.78, 0.80) in 2008. Long-term prescriptions significantly increased in patients with RA [from 10.3% (8.7, 11.9) to 13.6% (12.9, 14.2)] and PMR/GCA [from 57.6% (53.3, 62.0) to 66.5% (65.2, 67.7)], decreased in patients with asthma, COPD and Crohn's disease and remained stable in patients with UC. However, when only incident cases were considered, we found a decreased use of GCs in patients with RA and UC [odds ratio 0.97 (95% CI 0.96, 0.97) and 0.94 (95% CI 0.93, 0.96) per increasing year, respectively]. Conclusion. Over the past 20 years, long-term oral GC prescriptions have increased by 34%. Patients newly diagnosed with RA, Crohn's disease or UC are, however, less likely to receive long-term GC prescriptions than patients with a long past medical history of the disease, suggesting changes in physicians' practice.