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What Are the Pregnancy Rates When Combined Oral Contraceptive Pills Are Missed?

BACKGROUND AND PURPOSE:

  • Creinin et al. (Obstretrics & Gynecology, 2023) assessed the relationship of adherence and pregnancy in participants using a combined oral contraceptive

METHODS:

  • Secondary analysis of two parallel, multicenter, phase 3 trials
  • Population
    • 16 to 35 years old
    • Receiving a combined oral contraceptive (estetrol 15 mg and drospirenone 3 mg)
    • Using a 24 hormone and 4 placebo pills regimen for up to 13 cycles
  • Exposures
    • Participant reported
      • Pill intake | Sexual intercourse | Other contraceptive use
  • Study design
    • Efficacy analysis was restricted to at-risk cycles (one or more reported acts of intercourse and no other contraceptive use)
    • Cycles with other contraceptive use were excluded, unless pregnancy occurred in that cycle
  • Primary outcome
    • Association between number of pills not taken per cycle and pregnancy
  • Secondary outcome
    • When pregnancies occurred during contraceptive use

RESULTS:

  • 2837 participants
    • At-risk cycles: 26,455
    • On-treatment pregnancies: 31
  • Occurrence of pregnancy based on missing pills (P<0.001)
    • No missed pills: 0.09%
    • 1 missed pill: 0.25%
    • 2 missed pills: 0.83%
    • >2 missed pills: 1.6%
  • No pregnancies occurred when one or more pills were missed and missed-pill instructions were followed
  • All pregnancies related to not taking pills occurred in the first three cycles

CONCLUSION:

  • In a 28-day cycle, there is a higher rate of pregnancy when oral contraceptive pills are missed
  • The pregnancy rate exceeds 1% only when more than 2 pills are missed
  • Following missed-pill instructions seems to reduce the incidence of pregnancy
  • The authors state

We found that the pregnancy risk per cycle was very low (0.09%) in participants who reported using all active hormone pills in a particular cycle, regardless of any new medications started or health issues

Learn More – Primary Sources:

Combined Oral Contraceptive Adherence and Pregnancy Rates

Are Abnormal Copy Number Variants Associated with Stillbirth and Fetal Growth Abnormalities?

BACKGROUND AND PURPOSE:

  • Fetal growth abnormalities, like small and large for gestational age (SGA, LGA), are associated with an increased risk of stillbirth
    • Many cases of SGA and LGA are not associated with any known clinical risk factors, and may be related to an unknown underlying genetic etiology
  • Dalton et al. (AJOG, 2023) assessed the relationship between abnormal copy number variants and fetal growth abnormalities in stillbirths using chromosomal microarray

METHODS:

  • Cohort study
  • Population
    • Stillbirths in the Stillbirth Collaborative Research Network
  • Exposure
    • Abnormal copy number variants including aneuploidies, pathogenic copy number variants, and variants of unknown clinical significance
  • Study design
    • Copy number variants determined using microarray (fetus or placenta)
  • Primary outcomes
    • SGA stillbirths: birthweight <10th percentile for gestational age
    • LGA stillbirths: >90th percentile for gestational age

RESULTS:

  • 393 stillbirths
    • Abnormal copy number variants: 16%
  • The SGA stillbirth outcome was more common among those with abnormal copy number variants (P=0.038)
    • Abnormal: 29.5% | Normal: 16.5%
    • Odds ratio (OR) 2.22 (95% CI, 1.12 to 4.18)
  • LGA age stillbirths were no more likely to have an abnormal microarray (P=0.275)
    • Abnormal: 6.2% | Normal: 3.3%
    • OR 2.35 (95% CI, 0.70 to 7.90)

CONCLUSION:

  • Abnormal copy number variants are more common in SGA stillbirths
  • The authors state

Our findings support the recent recommendations for chromosomal microarray in the evaluation of a stillbirth as opposed to karyotyping, especially in the setting of growth restriction, as roughly half of the genetic abnormalities associated with SGA stillbirths would not have been discovered with conventional karyotyping 

Learn More – Primary Sources:

Copy number variants and fetal growth in stillbirths

Meta-Analysis: Elective Induction at 39 Weeks and Rates of Maternal Labor-Related Complications

BACKGROUND AND PURPOSE:

  • Hong et al. (JAMA Network Open, 2023) examined maternal labor-related complications and neonatal outcomes following elective induction of labor at 39 weeks vs expectant management

METHODS:

  • Systematic review and meta-analysis
  • Study inclusion criteria
    • Randomized clinical trials | Cohort studies | Cross-sectional studies
    • Studies that reported perinatal outcomes following induction of labor at 39 weeks vs expectant management
  • Study design
    • Pooled odds ratios (ORs) and 95% CIs were calculated using a random-effects model
  • Primary outcomes
    • Maternal outcomes
      • Emergency cesarean section | Perineal injury | Postpartum hemorrhage | Operative vaginal birth
    • Neonatal outcomes
      • NICU Admission | 5-minute Apgar score <7 | Macrosomia | Shoulder dystocia

RESULTS:

  • 14 studies | 1,625,899 women
  • Induction of labor at 39 weeks of gestation reduced the likelihood of
    • Third- or fourth-degree perineal injury: OR 0.63 (95% CI, 0.49 to 0.81)
    • Operative vaginal birth: OR 0.87 (95% CI, 0.79 to 0.97)
    • Macrosomia: OR 0.66 (95% CI, 0.48 to 0.91)
    • Low 5-minute Apgar score: OR 0.62 (95% CI, 0.40 to 0.96)
  • Results were similar when confined to multiparous women only, with the addition of
    • A reduction in the likelihood of emergency cesarean section
      • OR 0.61 (95% CI, 0.38 to 0.98)
    • No difference in operative vaginal birth
      • OR 1.01 (95% CI, 0.84 to 1.21)
  • Among nulliparous women only, induction of labor was associated with an increased likelihood of shoulder dystocia
    • OR 1.22 (95% Ci, 1.02 to 1.46)

CONCLUSION:

  • Induction of labor at 39 weeks reduced the incidence of perineal injuries, macrosomia and low 5-min Apgar scores
    • Among multiparous women, it also reduced the likelihood of an emergency cesarean delivery
  • Among nulliparous women, induction at 39 weeks was associated with shoulder dystocia
  • The authors state

This review of 1 625 899 women from 14 studies found that elective induction of labor at 39 weeks of gestation compared with expectant management was associated with improved labor-related outcomes, including a 37% reduction in perineal injury risk

Learn More – Primary Sources:

Comparison of Maternal Labor-Related Complications and Neonatal Outcomes Following Elective Induction of Labor at 39 Weeks of Gestation vs Expectant Management: A Systematic Review and Meta-analysis

Meta-Analysis: Comparing Different Antiosteoporosis Medications and Fracture Risk Reduction

BACKGROUND AND PURPOSE:

  • Händel et al. (BMJ, 2023) assessed the comparative effectiveness of osteoporosis treatments on reducing the risk of fractures in postmenopausal women

METHODS:

  • Systematic review, network meta-analysis, and meta-regression analysis
  • Inclusion criteria
    • Randomized clinical trials
    • Studies that examined the effect of bisphosphonates, denosumab, selective estrogen receptor modulators, parathyroid hormone receptor agonists, and romosozumab compared with placebo or active comparator
    • Studies that included non-Asian postmenopausal women with no restriction on age
  • Study design
    • Bias and heterogeneity were assessed  
  • Primary outcome
    • Clinical fractures
  • Secondary outcomes
    • Vertebral, non-vertebral, hip, and major osteoporotic fractures
    • Harm outcomes: All-cause mortality | Number of patients with any adverse events | Number of patients with serious cardiovascular adverse event

RESULTS:

  • 69 trials | >80,000 patients
  • Compared to placebo, the following provided protection against clinical fractures
    • Bisphosphonates | Parathyroid hormone receptor agonists | Romosozumab
  • Compared with parathyroid hormone receptor agonists, bisphosphonates were less effective in reducing clinical fractures
    • Odds ratio (OR) 1.49 (95% CI, 1.12 to 2.00)
  • Compared with parathyroid hormone receptor agonists and romosozumab, denosumab was less effective in reducing clinical fractures
    • Parathyroid hormone receptor agonist vs denosumab: OR 1.85 (95% CI, 1.18 to 2.92)
    • Romosozumab vs denosumab: OR 1.56 (95% CI, 1.02 to 2.39)
  • Compared to placebo, all treatments provided protection against vertebral fractures
  • The effect of all treatments was unaffected by baseline risk indicators except for antiresorptive treatments showed a greater reduction of clinical fractures compared with placebo with increasing mean age
  • There were no harm outcomes observed
  • Certainty of effect estimates was moderate to low

CONCLUSION:

  • Many antiosteoporosis medications provided protection against clinical and vertebral fractures in postmenopausal women
  • Bone anabolic treatments were more effective than bisphosphonates
  • The authors state

Because bone anabolic treatments were more effective than bisphosphonates, irrespective of the baseline risk, no evidence from clinical trials exists supporting the view that bone anabolic treatment should be limited to patients at very high risk of fractures because of efficacy

Learn More – Primary Sources:

Fracture risk reduction and safety by osteoporosis treatment compared with placebo or active comparator in postmenopausal women: systematic review, network meta-analysis, and meta-regression analysis of randomised clinical trials

RCT Results: IV vs Oral Iron for Postpartum Anemia?

BACKGROUND AND PURPOSE:

  • Saad et al. (Obstetrics & Gynecology, 2023) evaluated the feasibility of administering IV iron postpartum prior to discharge for the management of anemia

METHODS:

  • Double-blinded, feasibility randomized controlled trial
  • Participants
    • Delivery at a single academic hospital
    • Hemoglobin levels <9 g/dL on postpartum day 1
  • Interventions
    • IV group
      • Test-dose of 25 mg IV iron infusion, followed by iron 1,000 mg in 500 mL 0.9% sodium chloride infusion
      • Placebo pills
    • Oral group
      • Placebo test-dose and infusion
      • 6-week supply of 3x daily oral iron supplements (ferrous sulfate 325 mg, 65 mg elemental iron)
  • Study design
    • Compliance was assessed by asking participants to bring pill containers to all follow-up visits
  • Primary outcome
    • Hemoglobin level at or after 6 weeks postpartum
  • Secondary outcome
    • Adverse effects
    • Need for transfusion in the 6-week postpartum period
    • Postpartum fatigue using a validated instrument
    • Postpartum depression

RESULTS:

  • 40 participants
  • Patients randomized to IV iron had higher hemoglobin levels after 6 weeks postpartum, compared to those in the oral iron group
    • Median hemoglobin levels (P=0.03)
      • IV: 12.3 (range, 10.6 to 13.8) g/dL
      • Oral: 11.7 (range, 9.9 to 12.6) g/dL
    • Percent increase in hemoglobin levels (P=0.04)
      • IV: 50.6% (27.4 to 90.2)
      • Oral: 42.7% (22.2 to 50.6)
  • There was no difference in adverse effects between the two groups
  • Rates of postpartum fatigue and depression also did not differ between the groups

CONCLUSION:

  • IV iron infusion before discharge following delivery improved iron levels in the first 6 weeks postpartum, compared to oral iron supplementation
  • The authors state

Our trial shows that it is feasible to administer IV iron during the delivery admission and that larger multicenter clinical trials are warranted

Learn More – Primary Sources:

Intravenous Iron Compared With Oral Iron Supplementation for the Treatment of Postpartum Anemia

Treatment for Cesarean Scar Ectopic Pregnancy: D&E or Hysteroscopic Resection?

BACKGROUND AND PURPOSE:

  • There is no consensus on best treatment practices for managing cesarean scar ectopic pregnancy (CSP)
  • Di Spiezio Sardo et al. (AJOG, 2023) compared the success rate of hysteroscopic resection vs ultrasound-guided dilation and evacuation (D&E) for treatment of CSP

METHODS:

  • Parallel group, nonblinded, randomized clinical trial
  • Participants
    • CSP with positive embryonic heart activity
    • Opted for termination of pregnancy
    • myometrial layer thickness ≥1 mm
  • Interventions
    • Hysteroscopic resection
      • Performed under spinal anesthesia | Using 15 Fr bipolar miniresectoscope
    • Ultrasound guided D&E
      • Vacuum aspiration with Karman cannula | Followed by sharp curettage, if necessary, under ultrasound guidance
  • Study design
    • Both groups received 50 mg/m2 of methotrexate (MTX) IM at the time of randomization (day 1) and another dose at day 3
      • Third dose was planned in case of persistence of positive fetal heart activity at day 5
    • Intervention occurred after the last dose of MTX
    • Resolution of CSP was evaluated based on decline of Beta-hCG and absence of residual gestational material in the endometrial cavity
    • Sample size calculation: 54 participants
  • Primary outcome
    • Success rate of treatment: Defined as no further treatment required until the complete resolution of the CSP

RESULTS:

  • Hysteroscopic resection: 27 women | D&E: 27 women
  • Received a third dose of MTX: 10 women
    • Hysteroscopic resection: 25.9% | D&E: 11.1%
  • Success rate was higher in the hysteroscopic resection group
    • Hysteroscopic resection: 100% | D&E: 81.5%
    • Relative risk (RR) 1.22 (95% CI, 1.01 to 1.48)
  • Additional procedures were required for 5 participants in the D&E group
    • Hysterectomies: 3 | Laparotomic uterine segmental resection: 1 | Hysteroscopic resection: 1
  • There was no significant difference in length of hospital stay between the groups
    • Hysteroscopic resection: 9.0 ± 2.9 days | D&E: 10.0 ± 3.5 days
    • Mean difference –1.00 days (95% CI, –2.71 to 0.71)
  • There were no admissions to the ICU or maternal deaths reported

CONCLUSION:

  • Hysteroscopic resection has a greater treatment success rate for cesarean scar ectopic pregnancy compared to D&E
  • The authors state

A hysteroscopic resection was associated with an increase in the success rate of CSP treatment when compared with ultrasound-guided D&E 

Learn More – Primary Sources:

Hysteroscopic resection vs ultrasound-guided dilation and evacuation for treatment of cesarean scar ectopic pregnancy: a randomized clinical trial

Is Interrupting Breast Cancer Therapy During Pregnancy a Safe Approach?

BACKGROUND AND PURPOSE:

  • Partridge et al. (NEJM, 2023) assessed the risk of breast cancer recurrence associated with a temporary interruption of endocrine therapy to attempt pregnancy in premenopausal women with endocrine-responsive early breast cancer

METHODS:

  • International, multicenter, investigator-initiated, single-group trial 
  • Participants
    • ≤42 years and desired pregnancy
    • Stage I, II or III breast cancer
    • Received adjuvant endocrine therapy for 18 to 30 months
  • 516 women
    • Median age: 37 years
    • Median time from breast cancer diagnosis to enrollment: 29 months
    • Stage I or II disease: 93.4%
  • Exposure
    • Temporary interruption of adjuvant endocrine therapy to attempt pregnancy
    • A control cohort consisted of women who would have met the criteria for enrollment in the trial
  • Study design
    • Primary analysis was planned to occur after 1600 patient-years of follow-up
    • The prespecified safety threshold was the occurrence of 46 breast cancer events during this period
  • Primary outcome
    • Number of breast cancer events during follow-up
      • Events were defined as local, regional, or distant recurrence of invasive breast cancer or new contralateral invasive breast cancer

RESULTS:

  • 516 women
    • Median age: 37 years
    • Median time from breast cancer diagnosis to enrollment: 29 months
    • Stage I or II disease: 93.4%
  • Patient years of follow-up: 1638
    • Median follow-up: 41 months
  • Pregnancy rate: 74.0% | Live birth rate: 63.8%
  • Breast cancer events: 44
    • This number did not exceed the prespecified safety threshold
  • 3-year incidence of breast cancer events
    • Treatment interruption: 8.9% (95% CI, 6.3 to 11.6)
    • Control: 9.2% (95% CI, 7.6 to 10.8)

CONCLUSION:

  • Temporary cessation of endocrine therapy to attempt pregnancy did not increase the incidence of breast cancer recurrence in the short-term
  • Long-term follow-up is necessary to ensure safety of treatment interruption
  • The authors state

In well-matched comparisons to an external control cohort, the POSITIVE trial showed no clear worsening of breast cancer outcomes in the short term after temporary interruption of endocrine therapy to allow for pregnancy in select women with a history of hormone receptor–positive breast cancer

Learn More – Primary Sources:

Interrupting Endocrine Therapy to Attempt Pregnancy after Breast Cancer

RCT Results: Does Immediate GDM Treatment Prior to 20 Weeks Improve Neonatal Outcomes?

BACKGROUND AND PURPOSE:

  • Simmons et al. (NEJM, 2023) assessed pregnancy outcomes after treatment for GDM had been initiated before 20 weeks gestation, as compared with deferred or no treatment

METHODS:

  • Randomized controlled trial
    • Multicenter | 17 Hospitals
  • Participants
    • ≥18 years
    • 4w0d to 19w6d
    • ≥1 risk factor for hyperglycemia
  • Intervention
    • Immediate treatment for GDM
    • Deferred or no treatment, depending on the results of a repeat oral glucose-tolerance test (OGTT) at 24 to 28 weeks gestation
  • Primary outcomes
    • Composite of adverse neonatal outcomes
      • Birth at <37 weeks’ gestation | Birth trauma | Birth weight of ≥4500 g | Respiratory distress | Phototherapy | Stillbirth or neonatal death | Shoulder dystocia
    • Pregnancy-related hypertension
      • Preeclampsia | Eclampsia | Gestational hypertension
    • Neonatal lean body mass

RESULTS:

  • Immediate treatment: 406 women | Control: 396 women
    • Initial GA at time of first OGTT: Mean 15.6 (SD, 2.5) weeks
  • There were fewer adverse neonatal outcome events reported in the immediate-treatment group
    • Immediate treatment: 24.9% | Control: 30.5%
    • Adjusted risk difference −5.6 percentage points (95% CI, −10.1 to −1.2)
  • There was no significant difference in
    • Pregnancy-related hypertension
      • Immediate treatment: 10.6% | Control: 9.9%
      •  Adjusted risk difference 0.7 percentage points (95% CI, −1.6 to 2.9)
    • Mean neonatal lean body mass
      • Immediate treatment: 2.86 g | Control: 2.91 g
      • Adjusted mean difference −0.04 g (95% CI, −0.09 to 0.02)
  • There were no differences in serious treatment- or screening-related adverse events between the groups

CONCLUSION:

  • Starting GDM treatment immediately, prior to 20 weeks, led to a small reduction in adverse neonatal outcomes
  • No other benefits to immediate treatment with regard to pregnancy-related hypertension or neonatal body mass were notes
  • The authors state

In this trial involving pregnant women who had a risk factor for hyperglycemia, immediate treatment of gestational diabetes before 20 weeks’ gestation led to a modestly lower incidence of a composite of severe adverse neonatal outcomes than no immediate treatment

Learn More – Primary Sources:

Treatment of Gestational Diabetes Mellitus Diagnosed Early in Pregnancy

What are the Red-Flag Signs of Early-Onset Colorectal Cancer? 

BACKGROUND AND PURPOSE:

  • Fritz et al. (Journal of the National Cancer Institute, 2023) identified red-flag signs and symptoms associated with early-onset colorectal cancer (CRC)

METHODS:

  • Matched case-control study
    • US population | Commerical Insurance
  • Population
    • 18 to 64 years
  • Exposures
    • Early-onset CRC
    • Matched controls
  • Study design
    • Diagnostic intervals were assessed according to the presence of signs and symptoms before and within 3 months of diagnosis
  • Primary outcomes
    • Red-flag signs and symptoms between 3 months to 2 years before the index date
      • There were 17 pre-specified signs and symptoms

RESULTS:

  • Early-onset CRC patients: 5075
  • Four red-flag signs and symptoms were associated with an increased risk of early-onset CRC
    • Abdominal pain
      • Cases: 11.6% | Controls: 7.7%
      • Odds ratio (OR) 1.34 (95% CI, 1.19 to 1.49)
    • Rectal bleeding
      • Cases: 7.2% | Controls: 1.3%
      • OR 5.13 (95% CI, 4.36 to 6.04)
    • Diarrhea
      • Cases: 2.8% | Controls: 1.4%
      • OR 1.43 (95% CI, 1.14 to 1.78)
    • Iron deficiency anemia
      • Cases: 2.3% | Controls: 0.9%
      • OR 2.07 (95% CI, 1.61 to 2.66)
  • Having 1, 2, or ≥ 3 of these signs/symptoms was associated with increasing risk (Ptrend<0.001)
    • 1 sign/symptom: OR 1.94 (95% CI, 1.76 to 2.14)
    • 2 signs/symptoms: OR 3.59 (95% CI, 2.89 to 4.44)
    •  ≥ 3 signs/symptoms: OR 6.52 (95% CI, 3.78 to 11.23)
  • There were stronger associations for
    • Younger ages: Pinteraction<0.001
    • Rectal cancer: Pheterogenity=0.012
  • The number of different signs and symptoms was predictive of early-onset CRC beginning 18 months before diagnosis
  • First sign and/or symptom occurred between 3 months and 2 years before diagnosis: 19.3%
    • Median diagnostic interval: 8.7 months
  • First sign and/or symptom occurred with 3 months of diagnosis: 49.3%
    • Median diagnostic interval: 0.53 months

CONCLUSION:

  • Red-flag signs and symptoms of early-onset CRC are abdominal pain, rectal bleeding, diarrhea and iron deficiency anemia
  • The authors state

Early recognition of red-flag signs and symptoms (abdominal pain, rectal bleeding, diarrhea, and iron-deficiency anemia) may improve early detection and timely diagnosis of early-onset CRC

Learn More – Primary Sources:

Red-flag Signs and Symptoms for Earlier Diagnosis of Early-Onset Colorectal Cancer

RCT Results: Levonorgestrel IUD or Hysteroscopic Resection for Niche-Related Bleeding?

BACKGROUND AND PURPOSE:

  • Niche-related postmenstrual spotting and chronic pelvic pain can occur after cesarean delivery
  • Both the 52-mg levonorgestrel IUD (LNG IUD) and hysteroscopic niche resection have been shown to improve symptoms
  • Zhang et al. (AJOG, 2023) compare the effectiveness of the 52-mg LNG IUD with hysteroscopic niche resection in reducing niche-related postmenstrual spotting

METHODS:

  • Randomized, open-label, controlled trial
  • Participants
    • Women with symptoms of postmenstrual spotting after cesarean delivery
    • Niche depth of ≥2 mm and residual myometrium of ≥2.2 mm on MRI
    • Not planning to conceive within the next year
  • Intervention
    • 52-mg LNG IUD
    • Hysteroscopic niche resection
  • Study design
    • Efficacy and safety were assessed using intention-to-treat analysis
  • Primary outcome
    • Reduction in postmenstrual spotting at 6 months after randomization
      • Defined as percentage of women with a reduction of at least 50% in spotting days relative to baseline

RESULTS:

  • IUD: 104 participants | Hysteroscopic niche resection: 104
  • At 6-month follow-up: No difference in the number of women who achieved a 50% reduction in spotting
    • IUD: 78.4% | Niche resection: 73.1%
    • Relative Risk (RR) 1.07 (95% CI, 0.92 to 1.25) | P=0.370
  • Spotting decreased over time (Ptrend=0.001)
    • There was a stronger reduction observed in the IUD group (P=0.001)
    • There was a significant interaction between time and treatment (P=0.007)
  • ≥9 months: A more significant reduction in spotting was observed in the IUD group
    • 9 months
      • IUD: 89.2% | Niche resection: 72.1%
      • RR 1.24 (95% CI, 1.08 to 1.42)
    • 12 months
      • IUD: 80.2% | Niche resection: 70.2%
      • RR 1.29 (95% CI, 1.12 to 1.48)
  • IUD group had significantly
    • Fewer postmenstrual spotting days at ≥6 months (P<0.001)
    • Fewer total bleeding days at ≥6 months (P<0.001)
    • Less pelvic pain at ≥3 months (P<0.01)
  • No intervention-related complications were reported in any group
  • Side-effects
    • Hormone-related side effects: 10.8%
    • Spontaneous partial expulsion in IUD group: 2.0%
  • There were 3 unintended pregnancies in the niche resection group

CONCLUSION:

  • For women with niche-related postmenstrual spotting, there was no difference in spotting reduction at 6 months with levonorgestrel IUD vs hysteroscopic niche resection but by 9 months the IUD was better at reducing spotting
  • Pelvic pain was also improved in the IUD group as early as 3 months from intervention
  • The authors state

On the basis of these results, we recommend LNG-IUS as the first-line therapy for women with niche-related gynecologic symptoms and without an active desire to become pregnant

Learn More – Primary Sources:

Comparing levonorgestrel intrauterine system with hysteroscopic niche resection in women with postmenstrual spotting related to a niche in the uterine cesarean scar: a randomized, open-label, controlled trial

Is Increasing BMI Associated with Increased Risk of Severe Respiratory Disease Outcomes?

BACKGROUND AND PURPOSE:

  • Higher BMI has been associated with worse COVID-19 outcomes, but BMI’s association with other respiratory diseases is not well understood
  • Bohrmann et al. (JAMA, 2023) assessed the associations between BMI and risk of hospitalization or death due to COVID-19, lower respiratory tract infections (LRTIs), and upper respiratory tract infections (URTIs)

METHODS:

  • Population-based cohort study
  • Population
    • Individuals in the UK Biobank without chronic respiratory disease
  • Exposure
    • BMI
  • Study design
    • Cox proportional hazards models were used to determine hazard ratios (HR)
    • Reference group was individuals with BMI 25 to 29.9
    • Adjustments: Age | Sex | Region | Race | Townsend deprivation score | Education | Smoking | Alcohol intake
  • Primary outcome
    • Hospitalization or death due to COVID-19 | LRTIs (influenza, pneumonia) | URTIs (laryngitis, tonsillitis)

RESULTS:

    • Median age: 58 (IQR, 50 to 63) years | 54% female | 94% White
    • Mean BMI: 27.4 (SD, 4.7)
    • Mean follow-up: 11.8 years
  • Risk of all respiratory diseases was higher for BMI in the range of 35 to 60, compared to the reference group
    • COVID-19: aHR 2.38 (95% CI, 2.07 to 2.74)
    • LRTIs: aHR 1.91 (95% CI, 1.83 to 2.00)
    • URTIs: aHR 1.40 (95% CI, 1.20 to 1.64)
  • In the continuous analyses, there were positive log-linear associations of BMI with risk of severe COVID-19 and URTIs throughout the BMI categories
    • COVID-19: HR per 10-unit higher BMI 2.26 (95% CI, 2.05 to 2.49)
    • URTIs: HR per 10-unit higher BMI 1.37 (95% CI, 1.24 to 1.51)
  • There was a positive association of BMI with risk of LRTIs with BMI greater than 25
    • HR per 10-unit higher BMI 1.74 (95% CI, 1.68 to 1.80)

CONCLUSION:

  • Risk of hospitalization or death increased with increasing BMI for COVID-19 and URTIs
  • Risk of LRTIs increased with increasing BMI >25
  • The authors state

The findings suggest that the proposed mechanisms (including obesity-related chronic disease or compromised respiratory function) between BMI and COVID-19 might be shared by other LRTIs 

Learn More – Primary Sources:

Body Mass Index and Risk of Hospitalization or Death Due to Lower or Upper Respiratory Tract Infection