Table 2.
Associations between adverse pregnancy outcomes and subsequent risk of ischemic heart disease
| Adverse pregnancy outcomes and time after delivery | No with IHD | Incidence rate of IHD* | Hazard ratio (95% CI) | Incidence rate difference* (95% CI) | AFe (%) | PAF (%) | |
|---|---|---|---|---|---|---|---|
| Reduced model† | Full model‡ | ||||||
| ≤46 years: | |||||||
| Preterm delivery | 9424 | 210.0 | 1.39 (1.36 to 1.43) | 1.33 (1.30 to 1.37) | 66.2 (61.7 to 70.6) | 31.5 | 5.1 |
| Small for gestational age | 15 186 | 187.3 | 1.20 (1.18 to 1.22) | 1.18 (1.16 to 1.20) | 36.4 (33.2 to 39.6) | 19.4 | 3.5 |
| Pre-eclampsia | 10 043 | 269.8 | 1.44 (1.41 to 1.47) | 1.39 (1.37 to 1.42) | 121.9 (116.5 to 127.3) | 45.2 | 5.4 |
| Other hypertensive disorders of pregnancy | 1262 | 197.1 | 1.66 (1.56 to 1.76) | 1.56 (1.47 to 1.65) | 43.1 (31.4 to 54.9) | 21.9 | 0.3 |
| Gestational diabetes | 2340 | 266.2 | 1.58 (1.50 to 1.66) | 1.45 (1.38 to 1.52) | 113.0 (99.6 to 126.5) | 42.5 | 0.8 |
| <10 years: | |||||||
| Preterm delivery | 507 | 33.4 | 1.86 (1.68 to 2.05) | 1.72 (1.55 to 1.90) | 18.9 (16.0 to 21.9) | 56.6 | 11.9 |
| Small for gestational age | 548 | 18.7 | 1.14 (1.04 to 1.25) | 1.10 (1.00 to 1.21) | 1.6 (0.0 to 3.3) | 8.6 | 1.3 |
| Pre-eclampsia | 362 | 28.7 | 1.72 (1.54 to 1.93) | 1.54 (1.37 to 1.72) | 12.2 (9.2 to 15.2) | 42.4 | 4.4 |
| Other hypertensive disorders of pregnancy | 166 | 61.9 | 2.18 (1.85 to 2.57) | 2.09 (1.77 to 2.46) | 45.8 (35.6 to 55.9) | 73.9 | 3.1 |
| Gestational diabetes | 214 | 49.5 | 1.47 (1.23 to 1.76) | 1.30 (1.09 to 1.56) | 33.2 (24.4 to 42.0) | 67.1 | 2.4 |
| 10-19 years: | |||||||
| Preterm delivery | 1457 | 105.4 | 1.63 (1.54 to 1.73) | 1.51 (1.42 to 1.60) | 47.5 (41.9 to 53.2) | 45.1 | 9.6 |
| Small for gestational age | 1875 | 82.3 | 1.30 (1.24 to 1.37) | 1.27 (1.20 to 1.33) | 16.9 (12.9 to 20.9) | 20.5 | 3.7 |
| Pre-eclampsia | 1221 | 119.4 | 1.69 (1.59 to 1.80) | 1.55 (1.46 to 1.65) | 55.2 (48.3 to 62.0) | 46.2 | 5.4 |
| Other hypertensive disorders of pregnancy | 327 | 152.6 | 1.81 (1.61 to 2.04) | 1.68 (1.50 to 1.89) | 88.3 (70.1 to 106.4) | 57.8 | 1.6 |
| Gestational diabetes | 528 | 172.0 | 1.57 (1.40 to 1.76) | 1.43 (1.27 to 1.59) | 107.7 (87.5 to 128.0) | 62.7 | 1.8 |
| 20-29 years: | |||||||
| Preterm delivery | 3246 | 327.9 | 1.45 (1.40 to 1.51) | 1.37 (1.32 to 1.43) | 105.7 (93.9 to 117.5) | 32.2 | 5.8 |
| Small for gestational age | 4803 | 284.8 | 1.22 (1.18 to 1.26) | 1.19 (1.16 to 1.23) | 46.2 (37.5 to 54.9) | 16.2 | 2.9 |
| Pre-eclampsia | 3192 | 401.2 | 1.53 (1.48 to 1.59) | 1.47 (1.41 to 1.52) | 167.8 (153.5 to 182.0) | 41.8 | 5.0 |
| Other hypertensive disorders of pregnancy | 491 | 385.0 | 1.63 (1.49 to 1.79) | 1.52 (1.38 to 1.66) | 144.4 (107.7 to 181.1) | 37.5 | 0.6 |
| Gestational diabetes | 802 | 520.9 | 1.77 (1.63 to 1.92) | 1.61 (1.49 to 1.75) | 281.5 (236.3 to 326.6) | 54.0 | 1.1 |
| 30-46 years: | |||||||
| Preterm delivery | 4214 | 703.7 | 1.27 (1.23 to 1.31) | 1.23 (1.19 to 1.27) | 128.4 (106.1 to 150.8) | 18.3 | 2.5 |
| Small for gestational age | 7960 | 658.3 | 1.17 (1.14 to 1.20) | 1.16 (1.13 to 1.19) | 71.5 (55.8 to 87.2) | 10.9 | 2.0 |
| Pre-eclampsia | 5268 | 817.4 | 1.34 (1.30 to 1.38) | 1.32 (1.28 to 1.36) | 239.9 (217.1 to 262.7) | 29.4 | 3.6 |
| Other hypertensive disorders of pregnancy | 278 | 766.2 | 1.56 (1.38 to 1.76) | 1.47 (1.30 to 1.66) | 171.1 (75.6 to 266.6) | 22.3 | 0.1 |
| Gestational diabetes | 796 | 970.8 | 1.51 (1.40 to 1.63) | 1.40 (1.29 to 1.51) | 378.1 (299.9 to 456.3) | 38.9 | 0.5 |
AFe=attributable fraction among exposed; CI=confidence interval; IHD=ischemic heart disease; PAF=population attributable fraction.
*
Rate per 100 000 person years.
†
Adjusted for maternal age, year of delivery, parity, education, employment, income, country of origin, body mass index, smoking, and history of hypertension, diabetes, or hyperlipidemia.
‡
Additionally adjusted for all other adverse pregnancy outcomes.