Crowson, CS

ObjectiveThe objective of this study is to compare biologic drug discontinuation rates for older‐ versus younger‐onset rheumatoid arthritis (YORA) because this is a key outcome measure that could impact prescribing practices.MethodsWe performed a retrospective medical record review of all patients who fulfilled the 1987 American College of Rheumatology (ACR) criteria for adult‐onset rheumatoid arthritis (RA) in 1999‐2013 among residents of a geographically defined area, with follow‐up until death, migration, or July 1, 2017. Discontinuation rates were estimated using cumulative incidence adjusted for the competing risk of death.ResultsA total of 240 cases of elderly‐onset rheumatoid arthritis (EORA) and 366 cases of YORA were identified (65% and 73% female, respectively; P = 0.025). Cumulative incidence of biologic initiation was lower among the EORA cohort compared with the YORA cohort (18% vs 33%, respectively, at 10 years after RA incidence; P < 0.001). Among those treated with a biologic, years from RA diagnosis to first biologic treatment was not significantly different between the two groups (P = 0.62). Drug survival of first biologic was 64% at 1 year (95% confidence interval [CI]: 45%‐77%) and 53% at 2 years (95% CI: 33%‐66%) for EORA, compared with 61% at 1 year (95% CI: 50%‐69%) and 45% at 2 years (95% CI: 34%‐53%) for YORA (P = 0.75). Concurrent glucocorticoid use at initiation of first biologic was statistically and significantly associated with a lower risk of discontinuation in EORA (hazard ratio 0.21; 95% CI: 0.08‐0.53) but not in YORA (interaction P = 0.04).ConclusionDrug survival rates of biologic medications did not differ significantly between patients with EORA and YORA.

Objective To examine the influence of solar cycle and geomagnetic effects on the incidence of giant cell arteritis (GCA) and rheumatoid arthritis (RA). Methods We used data from patients with GCA (1950–2004) and RA (1955–2007) obtained from population-based cohorts. Yearly trends in age-adjusted and sex-adjusted incidence were correlated with the F10.7 index (solar radiation at 10.7 cm wavelength, a proxy for the solar extreme ultraviolet radiation) and AL index (a proxy for the westward auroral electrojet and a measure of geomagnetic activity). Fourier analysis was performed on AL, F10.7, and GCA and RA incidence rates. Results The correlation of GCA incidence with AL is highly significant: GCA incidence peaks 0–1 year after the AL reaches its minimum (ie, auroral electrojet reaches a maximum). The correlation of RA incidence with AL is also highly significant. RA incidence rates are lowest 5–7 years after AL reaches maximum. AL, GCA and RA incidence power spectra are similar: they have a main peak (periodicity) at about 10 years and a minor peak at 4–5 years. However, the RA incidence power spectrum main peak is broader (8–11 years), which partly explains the lower correlation between RA onset and AL. The auroral electrojets may be linked to the decline of RA incidence more strongly than the onset of RA. The incidences of RA and GCA are aligned in geomagnetic latitude. Conclusions AL and the incidences of GCA and RA all have a major periodicity of about 10 years and a secondary periodicity at 4–5 years. Geomagnetic activity may explain the temporal and spatial variations, including east-west skewness in geographic coordinates, in GCA and RA incidence, although the mechanism is unknown. The link with solar, geospace and atmospheric parameters need to be investigated. These novel findings warrant examination in other populations and with other autoimmune diseases.

Mycophenolate mofetil (MMF) is effective in the treatment of patients with active systemic lupus erythematosus (SLE). We sought to evaluate its efficacy in reducing the number of disease flares in adults with SLE. For this retrospective study, all patients seen at our institution over a six year period, 1999–2005, with the diagnosis of SLE treated with MMD were identified. Data regarding lupus flare was obtained for patients at least one and up to two years prior to starting MMF. The number of flares prior to MMF therapy was compared to the number of lupus flares in the one to two year period after starting MMF. Clinical assessment was performed with the SELENA-SLEDAI instrument. Differences between groups were compared using the signed rank test. The rate of flares (flares per person-year), before and after the introduction of MMF were compared assuming the occurrence of flares followed a Poisson distribution. In the evaluable 67 patients, the mean time period of followup prior to starting MMF was 14.1 months (range 0.3–24), mean time period of follow-up after starting MMF was 14.8 months (range 1.5–24); and mean MMF dose was 1328 mg/day (range 250–3000). The mean flare rate was reduced from 8.9 to 5.3 per 10 personyears and the mean prednisone dose was reduced on average 7.3 mg/day after starting MMF therapy. MMF treatment significantly reduced the total number of lupus flares and prednisone requirements. Even with the reduction in mean daily prednisone dose, both the SLEDAI and physican global assessment also improved during MMF therapy.