Table 2.
Risk factors for incidence of anemia during postpartum period (Hb <11)
| No. of anemic patients | Univariate rate ratio (95% CI)a | P-valuea | Multivariate rate ratio (95% CI)a | P-valuea | |
|---|---|---|---|---|---|
| Maternal age (years) | |||||
| <20 | 53 | 1.26 (0.91, 1.75) | 0.06b | 1.24 (0.88, 1.75) | 0.03b |
| 20–24 | 110 | 1.0 | 1.0 | ||
| 25–29 | 73 | 0.81 (0.60, 1.09) | 0.77 (0.57, 1.05) | ||
| ≥30 | 55 | 0.87 (0.63, 1.21) | 0.81 (0.57, 1.15) | ||
| Baseline BMI (kg/m2) | |||||
| <22 | 56 | 1.13 (0.80, 1.60) | 0.70b | ||
| 22–24.99 | 73 | 1.0 | |||
| 25–29.99 | 77 | 0.90 (0.64, 1.23) | |||
| ≥30 | 40 | 1.11 (0.75, 1.63) | |||
| Postpartum BMI (kg/m2)c | |||||
| <22 | 61 | 1.01 (0.70, 1.44) | 0.87b | ||
| 22–24.99 | 57 | 1.0 | |||
| 25–29.99 | 55 | 0.97 (0.67, 1.40) | |||
| ≥30 | 29 | 0.90 (0.57, 1.41) | |||
| Baseline MUAC | |||||
| >Median | 143 | 1.0 | 0.96b | ||
| ≤Median | 149 | 1.09 (0.87, 1.37) | |||
| Postpartum MUACc | |||||
| >Median | 159 | 1.0 | 0.27b | ||
| ≤Median | 133 | 1.30 (1.00, 1.69) | |||
| No. of previous pregnancies | |||||
| 0 (primigravida) | 129 | 1.0 | 0.60b | ||
| 1 | 85 | 0.98 (0.74, 1.29) | |||
| 2 | 39 | 0.79 (0.55, 1.13) | |||
| ≥3 | 38 | 1.03 (0.72, 1.48) | |||
| Weeks gestation at baseline | |||||
| ≥Median | 153 | 1.0 | 0.66b | ||
| <Median | 139 | 1.04 (0.83, 1.31) | |||
| Baseline CD4 count | |||||
| ≥500 | 282 | 1.0 | 0.48b | ||
| <500 | 10 | 1.08 (0.57, 2.06) | |||
| Postpartum CD4 countc | |||||
| ≥500 | 280 | 1.0 | 0.003d | 1.0 | 0.003b |
| <500 | 12 | 1.50 (0.83, 2.71) | 1.73 (0.96, 3.17) | ||
| Socio-economic characteristics | |||||
| Per day spending for food | |||||
| >500 | 189 | 1.0 | 0.38 | ||
| ≤500 | 103 | 1.12 (0.87, 1.43) | |||
| Marital status | |||||
| Married | 189 | 1.0 | |||
| Other | 103 | 1.04 (0.82, 1.33) | 0.73 | ||
| Education status | |||||
| 0–4 | 28 | 1.40 (0.76, 2.60) | 0.41b | ||
| 5–7 | 190 | 1.15 (0.69, 1.91) | |||
| 8–11 | 57 | 1.24 (0.71, 2.15) | |||
| 12 or More | 16 | 1.0 | |||
| Owns/possesses | |||||
| Sofa | 231 | 1.06 (0.79, 1.40) | 0.71 | ||
| No | 61 | 1.0 | |||
| Television | 129 | 1.17 (0.92, 1.47) | 0.20 | ||
| No | 163 | 1.0 | |||
| Cohabitates with partner | 53 | 0.86 (0.64, 1.16) | 0.33 | ||
| No | 239 | 1.0 | |||
| Radio | 238 | 0.76 (0.56, 1.02) | 0.07 | 0.85 (0.63, 1.16) | 0.32 |
| No | 54 | 1.0 | 1.0 | ||
| Refrigerator | 80 | 0.82 (0.64, 1.07) | 0.14 | 0.88 (0.67, 1.16) | 0.36 |
| No | 212 | 1.0 | 1.0 | ||
| Fan | 168 | 1.03 (0.81, 1.30) | 0.81 | ||
| No | 124 | 1.0 | |||
| Filmer–Pritchett wealth score | |||||
| ≥Median | 182 | 1.0 | |||
| <Median | 110 | 0.92 (0.73, 1.17) | 0.51 | ||
| Dietary characteristics | |||||
| Consumed alcohol at enrollment | 34 | 1.36 (0.91, 2.03) | 0.14 | 1.27 (0.84, 1.92) | 0.26 |
| No alcohol | 148 | 1.0 | 1.0 | ||
| History of meat use at enrollment | |||||
| At least one per month | 220 | 1.0 | |||
| Less | 72 | 1.02 (0.78, 1.33) | 0.87 | ||
| History of soil use at enrollment | |||||
| At least 1 per month | 14 | 1.0 | |||
| Less | 278 | 0.99 (0.55, 1.76) | 0.97 | ||
| Fe sups adherence during pregnancy | |||||
| ≤Median | 77 | 1.0 | 1.0 | ||
| >Median | 215 | 0.58 (0.45, 0.75) | 0.001 | 0.60 (0.46, 0.80) | 0.0004 |
| Breastfeeding since last visit | |||||
| Yes | 8 | 1.06 (0.52, 2.15) | 0.87 | ||
| No | 284 | 1.0 | |||
| Iron intakec | |||||
| Tertile 1 | 12 | 1.0 | 0.76b | ||
| Tertile 2 | 19 | 1.27 (0.61, 2.62) | |||
| Tertile 3 | 10 | 0.75 (0.33, 1.75) | |||
| Vitamin C intakec | |||||
| Tertile 1 | 12 | 1.0 | 0.73b | ||
| Tertile 2 | 16 | 1.12 (0.53, 2.36) | |||
| Tertile 3 | 13 | 1.10 (0.50, 2.40) | |||
| Vitamin B12 intakec | |||||
| Tertile 1 | 22 | 1.0 | 0.07b | 1.0 | 0.06b |
| Tertile 2 | 7 | 0.82 (0.35, 1.93) | 0.85 (0.36, 2.00) | ||
| Tertile 3 | 12 | 0.72 (0.36, 1.46) | 1.06 (0.45, 2.48) | ||
| Vitamin B6 intakec | |||||
| Tertile 1 | 15 | 1.0 | 0.32d | ||
| Tertile 2 | 15 | 0.90 (0.44, 1.84) | |||
| Tertile 3 | 11 | 0.62 (0.28, 1.35) | |||
| Folate intakec | |||||
| Tertile 1 | 13 | 1.0 | 0.73b | ||
| Tertile 2 | 14 | 1.22 (0.57, 2.60) | |||
| Tertile 3 | 14 | 1.09 (0.51, 2.31) | |||
| Heme iron intakec | |||||
| Tertile 1 | 35 | 1.0 | 0.12b | 1.0 | 0.24b |
| Tertile 2 | 6 | 0.57 (0.24, 1.37) | 0.57 (0.19, 1.65) | ||
| Tertile 3 | 0 | — | — | ||
| Medical characteristics | |||||
| History of eclampsia | 1 | 0.32 (0.05, 2.28) | 0.26 | ||
| No | 291 | 1.0 | |||
| Fansidar this pregnancy | 45 | 0.82 (0.60, 1.13) | 0.22 | ||
| No | 247 | 1.0 | |||
| Diarrhea this pregnancy | 11 | 1.10 (0.60, 2.02) | 0.75 | ||
| No | 281 | 1.0 | |||
| Vaginal bleeding this pregnancy | 13 | 0.76 (0.44, 1.33) | 0.34 | ||
| No | 279 | 1.0 | |||
| Malaria this pregnancy (prior to enroll) | 79 | 0.78 (0.60, 1.01) | 0.06 | 0.80 (0.61, 1.04) | 0.09 |
| No | 213 | 1.0 | 1.0 | ||
| Presumptive malariac | 2 | 0.68 (0.17, 2.72) | 0.58 | ||
| No | 290 | 1.0 | |||
| Postpartum malariac | 54 | 1.39 (1.01, 1.90) | 0.04 | 1.22 (0.88, 1.70) | 0.23 |
| No | 238 | 1.0 | 1.0 | ||
| Chlamydia | 3 | 2.77 (0.87, 8.80) | 0.08 | 2.70 (0.83, 8.79) | 0.10 |
| No | 289 | 1.0 | 1.0 | ||
| Delivery characteristics | |||||
| Delivery type | |||||
| Spontaneous vaginal delivery | 249 | 1.0 | 1.0 | ||
| Other | 43 | 1.51 (1.09, 2.09) | 0.001 | 1.58 (1.13, 2.22) | 0.007 |
| Blood loss (hemorrhage/transfusion at delivery) | 3 | 3.39 (1.08,10.59) | 0.04 | 2.91 (0.90, 9.37) | 0.07 |
| No | 289 | 1.0 | 1.0 | ||
Abbreviations: BMI, body mass index;
a
CI, confidence interval; Fe sups, iron supplements; TSh, Tanzanian shillings. Risk ratio, confidence intervals and P-values are from Cox proportional hazards models.
b
P-value corresponds to trend test.
c
Time-varying covariates. Analysis performed using Andersen–Gill data structure, with 5136 observations during follow-up period.
d
Association was significantly nonlinear. P-value corresponds to test of overall significance.