Table 2. Estimates From the Multivariable Logistic Regression of In-Hospital Mortality and Any SMM Among Hospital Inpatient Discharges for Newborn Delivery, 2008 to 2021.
| Variable | Adjusted OR (95% CI) | ||
|---|---|---|---|
| In-hospital mortalitya | In-hospital mortality sensitivity analysisb | Any SMMc | |
| Age group, y | |||
| 10-19 | 0.74 (0.48-1.14) | 0.61 (0.42-0.89) | 1.39 (1.36-1.42) |
| 20-24 | 0.90 (0.70-1.15) | 0.70 (0.56-0.86) | 1.10 (1.08-1.11) |
| 25-34 | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| 35-44 | 1.49 (1.22-1.84) | 2.16 (1.83-2.54) | 1.17 (1.16-1.19) |
| ≥45 | 1.95 (0.83-4.55) | 6.01 (3.16-11.41) | 1.76 (1.65-1.88) |
| Year | 0.89 (0.87-0.92) | 0.95 (0.93-0.97) | 1.02 (1.01-1.02) |
| Diagnosis code version (ICD-10-CM vs ICD-9-CM) | NE | NE | 0.92 (0.90-0.94) |
| Race | |||
| White | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| American Indian | 1.86 (0.95-3.64) | 1.93 (1.10-3.39) | 1.41 (1.35-1.48) |
| Asian | 1.37 (0.88-2.14) | 1.61 (1.11-2.34) | 1.33 (1.30-1.36) |
| Black | 1.09 (0.86-1.37) | 1.78 (1.47-2.15) | 1.39 (1.38-1.41) |
| Hispanic | 1.06 (0.81-1.39) | 1.04 (0.83-1.31) | 1.22 (1.20-1.24) |
| Other or unknown | 1.02 (0.77-1.35) | 1.19 (0.94-1.51) | 1.21 (1.19-1.22) |
| Pacific Islander | 0.89 (0.29-2.76) | 1.25 (0.48-3.26) | 1.53 (1.45-1.61) |
| Quarter | |||
| First | 0.80 (0.62-1.04) | 0.91 (0.74-1.13) | 0.99 (0.98-1.01) |
| Second | 0.88 (0.68-1.14) | 0.91 (0.74-1.13) | 0.99 (0.98-1.00) |
| Third | 1.02 (0.80-1.31) | 1.03 (0.85-1.26) | 1.00 (0.98-1.01) |
| Fourth | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Urbanicity of hospital population served (rural vs urban) | NE | NE | 0.88 (0.87-0.90) |
| Primary payer | |||
| Commercial | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Charity or indigent | 1.51 (0.27-8.53) | 2.36 (0.78-7.09) | 1.57 (1.42-1.73) |
| Medicaid | 1.73 (1.41-2.13) | 1.66 (1.4-1.97) | 1.22 (1.20-1.23) |
| Other | 1.72 (1.25-2.36) | 1.69 (1.31-2.20) | 1.23 (1.21-1.25) |
| Teaching hospital (vs nonteaching) | NE | NE | 1.18 (1.17-1.20) |
| Hospital region | |||
| South Atlantic | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| East North Central | 0.91 (0.67-1.24) | 0.87 (0.68-1.11) | 0.94 (0.93-0.95) |
| East South Central | 1.42 (1.00-2.02) | 1.29 (0.96-1.72) | 0.90 (0.88-0.92) |
| Middle Atlantic | 0.93 (0.68-1.27) | 0.91 (0.70-1.18) | 1.15 (1.13-1.16) |
| Mountain | 1.04 (0.70-1.54) | 1.31 (0.95-1.79) | 0.87 (0.85-0.89) |
| New England | 0.73 (0.35-1.53) | 0.62 (0.32-1.18) | 1.09 (1.06-1.12) |
| Pacific | 0.66 (0.48-0.92) | 0.66 (0.50-0.88) | 0.84 (0.83-0.86) |
| West North Central | 1.36 (0.90-2.07) | 1.28 (0.91-1.80) | 0.88 (0.86-0.90) |
| West South Central | 1.07 (0.80-1.45) | 1.11 (0.88-1.42) | 1.09 (1.08-1.11) |
| Admission type | |||
| Elective | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Emergent | 3.17 (2.48-4.04) | 5.17 (4.26-6.26) | 1.50 (1.48-1.52) |
| Urgent | 1.20 (0.96-1.49) | 1.55 (1.29-1.87) | 1.08 (1.06-1.09) |
| Trauma center | 16.65 (9.89-28.04) | 16.21 (10.36-25.35) | 1.40 (1.31-1.50) |
| Other or unknown | 1.46 (0.90-2.36) | 1.43 (0.96-2.15) | 1.28 (1.25-1.31) |
| Delivery type | |||
| Vaginal | 1 [Reference] | 1 [Reference] | 1 [Reference] |
| Cesarean | 2.28 (1.87-2.79) | 3.94 (3.34-4.64) | 3.00 (2.97-3.03) |
| Comorbidities (yes vs no) | |||
| COVID-19 diagnosis | 13.31 (8.95-19.79) | 41.63 (31.7-54.67) | 4.44 (4.23-4.66) |
| Placenta previa | NE | NE | 6.32 (6.17-6.47) |
| Sickle cell disease | NE | NE | 2.93 (2.82-3.05) |
| Gestational hypertension | NE | NE | 1.29 (1.26-1.31) |
| Mild or unspecified preeclampsia | NE | NE | 1.93 (1.89-1.97) |
| Severe preeclampsia | NE | NE | 4.55 (4.48-4.62) |
| Chronic kidney disease | NE | NE | 5.21 (4.99-5.44) |
| Preexisting hypertension | NE | NE | 1.54 (1.50-1.57) |
| Chronic ischemic heart disease | NE | NE | 3.92 (3.50-4.39) |
| Congenital heart disease | 0.07 (0.01-0.34) | 1.8 (0.46-7.08) | 2.43 (2.23-2.66) |
| Systemic lupus erythematosus | 3.68 (1.70-7.97) | 7.63 (4.28-13.62) | 1.95 (1.81-2.10) |
| HIV | 3.94 (1.30-11.92) | 3.03 (1.29-7.13) | 1.47 (1.33-1.63) |
| Multiple gestation | NE | NE | 2.20 (2.16-2.24) |
| Substance use disorder | 1.38 (1.00-1.91) | 3.44 (2.67-4.43) | 1.71 (1.67-1.75) |
| Alcohol abuse | NE | NE | 1.68 (1.52-1.85) |
| Cardiac valvular disease | 0.19 (0.10-0.33) | 6.73 (4.07-11.14) | 3.50 (3.32-3.69) |
| Asthma | NE | NE | 1.26 (1.24-1.28) |
| Preexisting diabetes | 1.70 (1.20-2.42) | 3.69 (2.81-4.86) | 1.22 (1.18-1.25) |
| Gestational diabetes | NE | NE | 0.96 (0.95-0.98) |
| Cystic fibrosis | 40.17 (7.22-223.56) | 35.97 (9.32-138.81) | 1.76 (1.22-2.52) |
| Previous cesarean delivery | NE | NE | 0.88 (0.87-0.89) |
| SMM (yes vs no) | |||
| Acute kidney failure | 1.30 (1.01-1.67) | Not included | Not included |
| Amniotic fluid embolism | 7.67 (5.28-11.14) | Not included | Not included |
| Aneurysm | 25.07 (7.40-84.91) | Not included | Not included |
| Disseminated intravascular coagulation | 2.21 (1.69-2.88) | Not included | Not included |
| Puerperal cerebrovascular disorder | 9.09 (6.11-13.51) | Not included | Not included |
| Sepsis | 1.90 (1.45-2.51) | Not included | Not included |
| Shock | 3.81 (2.96-4.91) | Not included | Not included |
| Air and thrombotic embolism | 2.63 (1.79-3.86) | Not included | Not included |
| Sickle cell anemia with crisis | 4.96 (2.17-11.33) | Not included | Not included |
| Bleeding complications (hemorrhage with no blood transfusion vs no bleeding) | 2.73 (2.06-3.61) | Not included | Not included |
| Bleeding complications (blood transfusion vs no bleeding) | 3.87 (3.05-4.91) | Not included | Not included |
| Hysterectomy | 1.69 (1.24-2.318) | Not included | Not included |
| Respiratory complicationsd | 5.92 (4.56-7.69) | Not included | Not included |
| Cardiovascular complicationse | 111.11 (86.69-142.42) | Not included | Not included |
Abbreviations: ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification; ICD-10-CM, International Statistical Classification of Diseases, Tenth Revision, Clinical Modification; NE, not entered in final model; OR, odds ratio; SMM, severe maternal morbidity.
Overall, 728 deaths among 11 628 380 inpatient hospitalizations were included in the analysis; 58 patients reported by hospitals with in-hospital mortality followed by readmission were excluded from the regression of mortality. Additional covariates included in the regression of mortality are described in the Statistical Analysis section.
A logistic regression of mortality without SMMs as covariates was performed as a sensitivity analysis.
A total of 189 908 discharges with SMM (of 11 628 438 inpatient hospitalizations) were included in the analysis. Additional covariates included in the regression of severe maternal morbidity are described in the Statistical Analysis section.
Respiratory complications included acute respiratory distress syndrome, temporary tracheostomy and ventilation as defined by the US Centers for Disease Control and Prevention.
Cardiovascular complications included any of the following severe maternal morbidities: acute myocardial infarction, cardiac arrest or ventricular fibrillation, conversion of cardiac rhythm, heart failure or arrest during surgery or procedure, and pulmonary edema or acute heart failure as defined by the US Centers for Disease Control and Prevention.