C3 and lupus nephritis: In the cohort with lupus nephritis (n = 32), drusen counts were higher in people aged >40 years (P < 0.045), with longer disease duration (P = 0.03), renal impairment (P = 0.02), or class IV nephritis (P = 0.03) and demonstrated a trend with C3 deposits (P = 0.098) (Table 3).