An assessment of outcomes and adherence to medications in patients with systemic lupus erythematosus with reference to ethnicity

This thesis explores clinical outcomes with respect to ethnicity in black, white and lndo-Asian patients with systemic lupus erythematosus (SLE) in the UCH cohort followed-up between 1978-2004 using cross-sectional studies involving retrospective analyses of patient records. It examines adherence to medications in SLE patients in the UCH cohort, and in Jamaica in the West Indies. Study number 1 which examined outcomes in patients with renal lupus showed that black patients were more likely to develop end stage renal failure (ESRF). High dsDNA antibody and low C3 levels were associated with progression to ESRF. Treatment adherence was poor in the majority of patients with ESRF (physician assessment). Study number 2 assessed the prevalence and chronology of development of additional autoimmune diseases (AID) in patients with SLE. A third of patients developed another AID. The total number of AID did not vary by ethnic group; however differences in the frequencies of some AID were noted. Mortality and damage scores were worse at 5 years in the study cases than the controls. Study number 3 assessed damage accrual and mortality in patients who had at least ten years of follow up over a 25 year period. Damage scores increased with time and were associated with a higher risk of mortality. Blacks had higher mortality than other ethnic groups. Sepsis was the main cause of death. Studies 4 and 5 determined self-reported adherence to medications in 220 patients in the UCH cohort and 75 in Jamaica. Interviews were conducted to determine why study participants did/did not take their medications regularly. Adherence did not differ between ethnic groups in the UCH cohort (assessed using the Morisky Medication Adherence Scale and a visual analogue scale). Beliefs and experiences with the drugs, SLE and physicians influenced adherence. Black patients reported feeling discriminated against by their white physicians. Fifty-two percent of the Jamaican patients took their medications regularly. High cost and poor availability of medications were important barriers to adherence. Perceived health benefits of drugs and good doctor: patient communication promoted high adherence. In conclusion, clinical outcomes in patients with SLE vary with respect to ethnicity. These differences may not necessarily relate to differences in treatment adherence