Table 3.
Association of percent changes in body weight with all-cause mortality by baseline BMI groups
| BMI | Weight changes | Minimal |
Case-mix |
Case-mix and MICS |
||||||
|---|---|---|---|---|---|---|---|---|---|---|
| (n = 58 106) |
(n = 51 052) |
(n = 38 828) |
||||||||
| HR | 95% CI | P | HR | 95% CI | P | HR | 95% CI | P | ||
| Between 1 and 5 months | ||||||||||
| <20 | ≤(−6%) | 1.98 | (1.68–2.33) | <0.001 | 2.04 | (1.70–2.44) | <0.001 | 1.52 | (1.24–1.87) | <0.001 |
| (−6%) to ≤(−2%) | 1.57 | (1.37–1.81) | <0.001 | 1.58 | (1.36–1.83) | <0.001 | 1.37 | (1.16–1.63) | <0.001 | |
| (−2%) to 2% | 1.25 | (1.11–1.42) | <0.001 | 1.38 | (1.21–1.57) | <0.001 | 1.25 | (1.07–1.45) | 0.004 | |
| 2% to <6% | 1.13 | (0.98–1.31) | 0.089 | 1.31 | (1.12–1.53) | 0.001 | 1.16 | (0.97–1.39) | 0.108 | |
| ≥6% | 1.32 | (1.14–1.55) | <0.001 | 1.47 | (1.24–1.74) | <0.001 | 1.41 | (1.15–1.72) | 0.001 | |
| 20 to <25 | ≤(−6%) | 1.54 | (1.41–1.67) | <0.001 | 1.40 | (1.27–1.53) | <0.001 | 1.14 | (1.02–1.27) | 0.020 |
| (−6%) to ≤(−2%) | 1.13 | (1.04–1.23) | 0.005 | 1.10 | (1.01–1.20) | 0.038 | 0.99 | (0.89–1.10) | 0.836 | |
| (−2%) to 2% | 1.0 | 1.0 | 1.0 | |||||||
| 2% to <6% | 0.92 | (0.84–1.02) | 0.106 | 0.93 | (0.84–1.03) | 0.152 | 0.90 | (0.80–1.02) | 0.091 | |
| ≥6% | 0.85 | (0.75–0.96) | 0.010 | 0.90 | (0.78–1.03) | 0.117 | 0.92 | (0.79–1.07) | 0.298 | |
| 25 to <30 | ≤(−6%) | 1.20 | (1.10–1.30) | <0.001 | 1.07 | (0.98–1.17) | 0.136 | 0.92 | (0.83–1.02) | 0.131 |
| (−6%) to ≤(−2%) | 1.03 | (0.95–1.12) | 0.443 | 0.99 | (0.90–1.08) | 0.760 | 0.98 | (0.88–1.08) | 0.647 | |
| (−2%) to 2% | 0.83 | (0.76–0.89) | <0.001 | 0.81 | (0.75–0.89) | <0.001 | 0.83 | (0.76–0.92) | <0.001 | |
| 2% to <6% | 0.77 | (0.69–0.86) | <0.001 | 0.77 | (0.69–0.86) | <0.001 | 0.83 | (0.73–0.94) | 0.005 | |
| ≥6% | 0.72 | (0.61–0.85) | <0.001 | 0.75 | (0.62–0.90) | 0.002 | 0.81 | (0.65–1.00) | 0.052 | |
| ≥30 | ≤(−6%) | 1.05 | (0.97–1.13) | 0.221 | 0.97 | (0.89–1.06) | 0.489 | 0.85 | (0.75–0.92) | <0.001 |
| (−6%) to ≤(−2%) | 0.78 | (0.72–0.84) | <0.001 | 0.77 | (0.70–0.84) | <0.001 | 0.75 | (0.67–0.83) | <0.001 | |
| (−2%) to 2% | 0.68 | (0.62–0.73) | <0.001 | 0.67 | (0.62–0.74) | <0.001 | 0.71 | (0.64–0.78) | <0.001 | |
| 2% to <6% | 0.72 | (0.64–0.81) | <0.001 | 0.77 | (0.68–0.87) | <0.001 | 0.84 | (0.72–0.97) | 0.015 | |
| ≥6% | 0.85 | (0.70–1.04) | 0.126 | 0.82 | (0.65–1.03) | 0.089 | 0.81 | (0.62–1.06) | 0.127 | |
| Between 5 and 12 months | ||||||||||
| <20 | ≤(−6%) | 3.04 | (2.58–3.58) | <0.001 | 3.18 | (2.64–3.82) | <0.001 | 1.67 | (1.33–2.10) | <0.001 |
| (−6%) to ≤(−2%) | 1.89 | (1.63–2.20) | <0.001 | 2.17 | (1.84–2.56) | <0.001 | 1.66 | (1.37–2.02) | <0.001 | |
| (−2%) to 2% | 1.37 | (1.22–1.55) | <0.001 | 1.51 | (1.32–1.73) | <0.001 | 1.39 | (1.19–1.62) | <0.001 | |
| 2% to <6% | 0.97 | (0.83–1.12) | 0.654 | 1.09 | (0.92–1.27) | 0.315 | 1.05 | (0.87–1.26) | 0.629 | |
| ≥6% | 1.23 | (1.06–1.41) | 0.005 | 1.25 | (1.07–1.46) | 0.004 | 1.16 | (0.97–1.38) | 0.103 | |
| 20 to <25 | ≤(−6%) | 2.38 | (2.07–2.51) | <0.001 | 2.32 | (2.09–2.58) | <0.001 | 1.49 | (1.31–1.68) | <0.001 |
| (−6%) to ≤(−2%) | 1.36 | (1.24–1.50) | <0.001 | 1.38 | (1.25–1.53) | <0.001 | 1.13 | (1.01–1.28) | 0.035 | |
| (−2%) to 2% | 1.0 | 1.0 | 1.0 | |||||||
| 2% to <6% | 0.93 | (0.85–1.02) | 0.106 | 0.94 | (0.86–1.04) | 0.223 | 0.94 | (0.85–1.05) | 0.277 | |
| ≥6% | 0.88 | (0.80–0.97) | 0.012 | 0.87 | (0.78–0.97) | 0.010 | 0.89 | (0.79–1.00) | 0.059 | |
| 25 to <30 | ≤(−6%) | 1.70 | (1.55–1.87) | <0.001 | 1.59 | (1.44–1.77) | <0.001 | 1.19 | (1.05–1.34) | 0.005 |
| (−6%) to ≤(−2%) | 1.19 | (1.09–1.31) | <0.001 | 1.13 | (1.02–1.25) | 0.015 | 1.04 | (0.92–1.16) | 0.548 | |
| (−2%) to 2% | 0.87 | (0.80–0.94) | <0.001 | 0.84 | (0.77–0.92) | <0.001 | 0.88 | (0.80–0.98) | 0.018 | |
| 2% to <6% | 0.75 | (0.69–0.82) | <0.001 | 0.72 | (0.65–0.80) | <0.001 | 0.77 | (0.69–0.87) | <0.001 | |
| ≥6% | 0.81 | (0.73–0.90) | <0.001 | 0.77 | (0.69–0.87) | <0.001 | 0.85 | (0.75–0.98) | 0.020 | |
| ≥30 | ≤(−6%) | 1.30 | (1.10–1.42) | <0.001 | 1.28 | (1.16–1.41) | <0.001 | 0.95 | (0.84–1.06) | 0.357 |
| (−6%) to ≤(−2%) | 0.90 | (0.83–0.99) | 0.028 | 0.87 | (0.78–0.96) | 0.005 | 0.80 | (0.71–0.90) | <0.001 | |
| (−2%) to 2% | 0.71 | (0.65–0.77) | <0.001 | 0.69 | (0.63–0.76) | <0.001 | 0.71 | (0.64–0.79) | <0.001 | |
| 2% to <6% | 0.69 | (0.63–0.76) | <0.001 | 0.64 | (0.58–0.72) | <0.001 | 0.69 | (0.61–0.78) | <0.001 | |
| ≥6% | 0.78 | (0.70–0.87) | <0.001 | 0.76 | (0.67–0.87) | <0.001 | 0.76 | (0.65–0.88) | <0.001 | |
Adjustments in minimally adjusted models: mortality data and weight of first month in each treatment period; case-mix adjusted models: minimally adjusted model plus baseline characteristics of age, sex, race/ethnicity (white, African American, Hispanic, Asian or other), primary insurance (Medicare, Medicaid or other), vascular access type (central venous catheter, arteriovenous fistula, arteriovenous graft or other), 10 comorbid conditions (diabetes mellitus, hypertension, atherosclerotic heart disease, congestive heart failure, other cardiovascular disease, cerebrovascular disease, dyslipidemia, HIV, chronic obstructive pulmonary disease and malignancy), alcohol dependence, substance abuse, dialysis ultrafiltration and dialysis dose as indicated by single-pool Kt/V; case-mix plus malnutrition-inflammation-cachexia syndrome (MICS) models: case-mix adjusted model plus 10 laboratory variables including white blood cells, lymphocytes, serum albumin, creatinine, bicarbonate, calcium, phosphorus, hemoglobin, total iron binding capacity and normalized protein catabolic rate. BMI, body mass index; HR, hazard ratio; CI, confidence interval.