Table 3.

Association of ethnicity with frequently relapsing nephrotic syndrome, relapse rate, time to first relapse, and second–line medication use among 455 children with nephrotic syndrome (1993–2014)

OutcomesEuropean, n=160South Asian, n=231East/Southeast Asian, n=64
Frequently relapsing nephrotic  syndrome at 12 mo
 Events, n34316
 Odds ratioReference0.570.38
 95% Confidence intervalNA0.38 to 0.880.38 to 0.39
 P valueNA0.010.001
 Adjusted odds ratioaReference0.550.42
 95% Confidence intervalNA0.39 to 0.770.34 to 0.51
 P valueNA0.0010.001
Relapse rate per person-yearb
 Relative riskReference0.760.57
 95% Confidence intervalNA0.53 to 1.110.30 to 1.06
 P valueNA0.160.07
 Adjusted relative riskaReference0.740.64
 95% Confidence intervalNA0.53 to 1.030.33 to 1.23
 P valueNA0.080.18
Developing first relapsec
 Events, n13417844
 Hazard ratioReference0.770.63
 95% Confidence intervalNA0.68 to 0.860.54 to 0.73
 P valueNA0.0010.001
 Adjusted hazard ratioaReference0.740.65
 95% Confidence intervalNA0.67 to 0.830.63 to 0.68
 P valueNA0.0010.001
Use of cyclophosphamide as  second-line medicationd
 Events, n607413
 Hazard ratioReference0.820.55
 95% Confidence intervalNA0.51 to 1.320.51 to 0.59
 P valueNA0.420.001
 Adjusted hazard ratioaReference0.820.54
 95% Confidence intervalNA0.53 to 1.280.41 to 0.71
 P valueNA0.390.001
  • Analysis excluded children with initial steroid resistance during the initial course among these three ethnicities (n=24). NA, not applicable.

  • a Adjusted for age at diagnosis and sex.

  • b By generalized linear model for log–transformed relapse rate.

  • c By Cox proportional hazards.

  • d Truncated at 5 years of follow-up.