Systemic lupus erythematosus in Indian patients: prognosis, survival and life expectancy.

ABSTRACT

BACKGROUND: There have been several studies on survival patterns in Indian patients with systemic lupus erythematosus but it is still not clear as to which factors at diagnosis predict survival outcome. The impact of specific organ involvement, and of disease activity itself, needs to be studied further. METHODS: We conducted a non-concurrent prospective study of 98 lupus patients between 1981 and 1993. The clinical symptoms, signs and investigation results at onset, and at subsequent visits, were abstracted from the case notes. A systemic lupus erythematosus disease activity index (SLEDAI) was constructed at the initial presentation and for each subsequent visit. Patients not attending for at least 6 months were traced by post. The quantitative data from the SLEDAI was used to construct a Markov chain mathematical expression designed to predict life expectancy. RESULTS: The cumulative percentage survival at 1, 5 and 10 years was found to be 89%, 77% and 60%, respectively. The Markov chain predicted a life expectancy of 13.9 years. Central nervous system and renal involvement were poor prognostic factors. Proteinuria (> 0.5 g/day) caused a 50% reduction in life expectancy but increased disease activity at onset did not predispose to a poor outcome. CONCLUSION: The survival of patients with systemic lupus erythematosus continues to be poor. Central nervous system and renal disease indicate a poor outcome. Hence, new treatment strategies must be evolved to improve the survival of such patients.