The humanistic and economic burden of systemic lupus erythematosus : a systematic review

Increased survival in patients with systemic lupus erythematosus (SLE) has shifted attention towards the burden that SLE imposes upon patients, healthcare systems and society. New interventions aimed at alleviating this burden will require economic evaluation. A summary of the current evidence of the humanistic and economic burden provides a platform for such subsequent studies.

The objective of this study was to systematically review the current evidence on the humanistic and economic burden of SLE in terms of health-related quality of life (HR-QOL) and costs, and summarize the evidence on the factors found to be associated with this burden.

Relevant literature for the years 1990 to February 2011 were obtained from systematic searches of MEDLINE, EMBASE and Web of Science. Articles reporting the humanistic (preference-based outcome measures or an SLE disease-specific HR-QOL measure) or economic burden (costs) of SLE in adult populations published in English were identified. The following exclusion criteria were applied: studies specifically examining lupus nephritis, SLE not being the main condition of focus (e.g. SLE is a co-existing condition), studies focusing on diagnostics or tests (including genetics and antibodies), mixed patient groups from which SLE could not be separated, paediatric populations, case studies, abstract unavailable, and non-English language studies. Estimates of the burden in terms of either HR-QOL or costs were extracted, tabulated and reported narratively. Annual cost figures were also converted into year 2010 US dollars using the consumer price index (CPI) and the purchasing power parity (PPP) conversion factor to allow for greater comparability across studies. Evidence on the factors found to be independently associated with either HR-QOL or costs was also examined.

Of the 1969 studies initially identified as being potentially relevant, 32 papers were retained for the final review. Eighteen of these presented estimates of the burden in terms of HR-QOL, and 14 in terms of the economic cost. Mean utility scores reported on preference-based measures of HR-QOL ranged from 0.6 to 0.75. Mean annual direct costs per patient ranged from US$2,214 to US$16,875, and mean annual indirect cost estimates from US$2,239 to US$35,540 (year 2010 values). Disease activity and damage, along with poor mental and physical health, were repeatedly reported to predict both reduced HR-QOL and increased costs.

The burden of SLE was found to be substantial, not only for patients but also for the health services that provide care for them. Treatments that are able to alleviate this burden are therefore likely to be highly valued by sufferers. After an extended period in which few therapeutic advances were made or treatments licensed, fundamental developments are finally being made. These new treatments will need to be evaluated for both clinical and cost effectiveness if their use is to be widely implemented.