Hypothetical interventions and risk of atrial fibrillation by sex and education: application of the parametric g-formula in the Tromsø Study.

AIMS: To use the parametric g-formula to estimate the long-term risk of atrial fibrillation (AF) by sex and education under hypothetical interventions on six modifiable risk factors. METHODS AND RESULTS: We estimated the risk reduction under hypothetical risk reduction strategies for smoking, physical activity, alcohol intake, body mass index, systolic, and diastolic blood pressure in 14 923 women and men (baseline mean age 45.8 years in women and 47.8 years in men) from the population-based Tromsø Study with a maximum of 22 years of follow-up (1994-2016). The estimated risk of AF under no intervention was 6.15% in women and 13.0% in men. This cumulative risk was reduced by 41% (95% confidence interval 17%, 61%) in women and 14% (-7%, 30%) in men under joint interventions on all risk factors. The most effective intervention was lowering body mass index to ≤ 25 kg/m2, leading to a 16% (4%, 25%) lower risk in women and a 14% (6%, 23%) lower risk in men. We found significant sex-differences in the relative risk reduction by sufficient physical activity, leading to a 7% (-4%, 18%) lower risk in women and an 8% (-2%, -13%) increased risk in men. We found no association between the level of education and differences in risk reduction by any of the interventions. CONCLUSION: The population burden of AF could be reduced by modifying lifestyle risk factors. Namely, these modifications could have prevented 41% of AF cases in women and 14% of AF cases in men in the municipality of Tromsø, Norway during a maximum 22-year follow-up period.

The heart normally has a regular rhythm. However, in an increasing number of adults worldwide, the rhythm is irregular, which is known as arrhythmia. Atrial fibrillation, or AF, is the most common type of arrhythmia. We know that the risk of AF may be related to lifestyle. In this project, we investigated how much the risk of AF in the population could have been reduced by improvements in smoking habits, physical activity level, alcohol intake, body mass index (BMI), and blood pressure. We found that the risk could have been reduced by 41% in women and 14% in men if everyone quit smoking, was sufficiently physically active, limited their alcohol intake to two units per week, lowered their BMI to 25 kg/m2, and lowered their blood pressure to 130/80 mm Hg. Reducing BMI was the most effective intervention to prevent AF.

COVID-19: seroprevalence and adherence to preventive measures in Arkhangelsk, Northwest Russia.

BACKGROUND: The published estimates of SARS-CoV-2 seroprevalence in Russia are few. The study aimed to assess the SARS-CoV-2 seroprevalence in Arkhangelsk (Northwest Russia), in a year after the start of the pandemic, to evaluate the population adherence to non-pharmaceutical interventions (NPIs), and to investigate characteristics associated with COVID-19 seropositive status. METHODS: We conducted a SARS-CoV-2 seroprevalence study between 24 February and 30 June 2021 involving 1332 adults aged 40-74 years. Logistic regression models were fit to identify factors associated with seropositive status and with adherence to NPIs. RESULTS: Less than half (48.9%) of study participants adhered all recommended NPIs. Male sex (odds ratio [OR] 1.7, 95% confidence intervals [CI] 1.3; 2.3), regular employment (OR 1.8, 95% CI 1.3; 2.5) and low confidence in the efficiency of the NPIs (OR 1.9, 95% CI 1.5; 2.5) were associated with low adherence to internationally recommended NPIs. The SARS-CoV-2 seroprevalence rate was 65.1% (95% CI: 62.5; 67.6) and increased to 73.0% (95% CI: 67.1; 85.7) after adjustment for test performance. Regular employment (OR 2.0, 95% CI 1.5; 2.8) and current smoking (OR 0.4, 95% CI 0.2; 0.5) were associated with being seropositive due to the infection. CONCLUSIONS: Two third of the study population were seropositive in a year after the onset of the pandemic in Arkhangelsk. Individuals with infection-acquired immunity were more likely to have regular work and less likely to be smokers. The adherence to NPIs was not found associated with getting the virus during the first year of the pandemic.

Sex-specific time trends in incident atrial fibrillation and the contribution of risk factors: the Tromsø Study 1994-2016.

AIMS: To explore sex-specific time trends in atrial fibrillation (AF) incidence and to estimate the impact of changes in risk factor levels using individual participant-level data from the population-based Tromsø Study 1994-2016. METHODS AND RESULTS: A total of 14 818 women and 13 225 men aged 25 years or older without AF were enrolled in the Tromsø Study between 1994 and 2008 and followed up for incident AF throughout 2016. Poisson regression was used for statistical analyses. During follow-up, age-adjusted AF incidence rates in women decreased from 1.19 to 0.71 per 1000 person-years. In men, AF incidence increased from 1.18 to 2.82 per 1000 person-years in 2004, and then declined to 1.94 per 1000 person-years in 2016. Changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP), body mass index (BMI), physical activity, smoking and alcohol consumption together accounted for 10.9% [95% confidence interval (CI): -2.4 to 28.6] of the AF incidence decline in women and for 44.7% (95% CI: 19.2; 100.0) of the AF incidence increase in men. Reduction in SBP and DBP had the largest contribution to the decrease in AF incidence in women. Increase in BMI had the largest contribution to the increase in AF incidence in men. CONCLUSION: In the population-based Tromsø Study 1994-2016, AF incidence decreased in women and increased following a reverse U-shape in men. Individual changes in SBP and DBP in women and individual changes in BMI in men were the most important risk factors contributing to the AF incidence trends.

Impact of introducing capacity-based mental health legislation on the use of community treatment orders in Norway: case registry study.

BACKGROUND: In 2017, a capacity-based criterion was added to the Norwegian Mental Health Act, stating that those with capacity to consent to treatment cannot be subjected to involuntary care unless there is risk to themselves or others. This was expected to reduce incidence and prevalence rates, and the duration of episodes of involuntary care, in particular regarding community treatment orders (CTOs). AIMS: The aim was to investigate whether the capacity-based criterion had the expected impact on the use of CTOs. METHOD: This retrospective case register study included two catchment areas serving 16% of the Norwegian population (aged ≥18). In total, 760 patients subject to 921 CTOs between 1 January 2015 and 31 December 2019 were included to compare the use of CTOs 2 years before and 2 years after the legal reform. RESULTS: CTO incidence rates and duration did not change after the reform, whereas prevalence rates were significantly reduced. This was explained by a sharp increase in termination of CTOs in the year of the reform, after which it reduced and settled on a slightly higher leven than before the reform. We found an unexpected significant increase in the use of involuntary treatment orders for patients on CTOs after the reform. CONCLUSIONS: The expected impact on CTO use of introducing a capacity-based criterion in the Norwegian Mental Health Act was not confirmed by our study. Given the existing challenges related to defining and assessing decision-making capacity, studies examining the validity of capacity assessments and their impact on the use of coercion in clinical practice are urgently needed.

Seroprevalence of SARS-Cov-2 Antibodies in Adults, Arkhangelsk, Russia.

Population-based data on coronavirus disease in Russia and on the immunogenicity of the Sputnik V vaccine are sparse. In a survey of 1,080 residents of Arkhangelsk 40-75 years of age, 65% were seropositive for IgG. Fifteen percent of participants had been vaccinated; of those, 97% were seropositive.

Shift work is associated with 10-year incidence of atrial fibrillation in younger but not older individuals from the general population: results from the Tromsø Study.

OBJECTIVES: Shift work is associated with myocardial infarction and stroke. We studied if shift work is also associated with incident atrial fibrillation (AF) and if this association differs, depending on sex and age. METHODS: We studied 22 339 participants (age 37.0±9.8 years, 49% women) with paid work from the third (1986-1987), fourth (1994-1995), fifth (2001) and sixth (2007-2008) surveys of the population-based Tromsø Study, Norway. Participants were followed up for ECG-confirmed AF through 2016. Shift work was assessed by questionnaire at each survey. We used unadjusted and multivariable-adjusted Cox regression models to study the association of shift work with 10-year incident AF and incident AF during extensive follow-up up to 31 years. Interactions with sex and age were tested in the multivariable model. RESULTS: Shift work was reported by 21% of participants at the first attended survey. There was an interaction between shift work and age for 10-year incident AF (p=0.069). When adjusted for AF risk factors, shift work was significantly associated with 10-year incident AF in participants <40 years (HR 2.90, 95% CI 1.12 to 7.49) but not≥40 years of age (HR 0.90, 95% CI 0.53 to 1.51). Shift work was not associated with incident AF during extensive follow-up (HR 1.03, 95% CI 0.89 to 1.20). There was no interaction between shift work and sex. CONCLUSIONS: Shift work was associated with 10-year incident AF in individuals <40 years but not ≥40 years of age. Shift work was not associated with incident AF during extensive follow-up up to 31 years, and there were no sex differences.

Sex-Specific Associations between Blood Pressure and Risk of Atrial Fibrillation Subtypes in the Tromsø Study.

The aim of this study was to explore sex-specific associations between systolic blood pressure (SBP), hypertension, and the risk of incident atrial fibrillation (AF) subtypes, including paroxysmal, persistent, and permanent AF, in a general population. A total of 13,137 women and 11,667 men who participated in the fourth survey of the Tromsø Study (1994-1995) were followed up for incident AF until the end of 2016. Cox proportional hazards regression analysis was conducted using fractional polynomials for SBP to provide sex- and AF-subtype-specific hazard ratios (HRs) for SBP. An SBP of 120 mmHg was used as the reference. Models were adjusted for other cardiovascular risk factors. Over a mean follow-up of 17.6 ± 6.6 years, incident AF occurred in 914 (7.0%) women (501 with paroxysmal/persistent AF and 413 with permanent AF) and 1104 (9.5%) men (606 with paroxysmal/persistent AF and 498 with permanent AF). In women, an SBP of 180 mmHg was associated with an HR of 2.10 (95% confidence interval [CI] 1.60-2.76) for paroxysmal/persistent AF and an HR of 1.80 (95% CI 1.33-2.44) for permanent AF. In men, an SBP of 180 mmHg was associated with an HR of 1.90 (95% CI 1.46-2.46) for paroxysmal/persistent AF, while there was no association with the risk of permanent AF. In conclusion, increasing SBP was associated with an increased risk of both paroxysmal/persistent AF and permanent AF in women, but only paroxysmal/persistent AF in men. Our findings highlight the importance of sex-specific risk stratification and optimizing blood pressure management for the prevention of AF subtypes in clinical practice.

Long-term blood pressure trajectories and incident atrial fibrillation in women and men: the Tromsø Study.

AIMS: To explore sex-specific associations between long-term individual blood pressure (BP) patterns and risk of incident atrial fibrillation (AF) in the general population. METHODS AND RESULTS: Blood pressure was measured in 8376 women and 7670 men who attended at least two of the three population-based Tromsø Study surveys conducted in 1986-87, 1994-95, and 2001. Participants were followed for incident AF throughout 2013. Latent mixed modelling was used to identify long-term trajectories of systolic BP and hypertension. Cox regression was used to estimate associations between the identified trajectories and incident AF. Elevated systolic BP throughout the exposure period (1986-2001) independently and differentially increased risk of AF in women and men. In women, having elevated systolic BP trajectories doubled AF risk compared to having persistently low levels, irrespective of whether systolic BP increased, decreased, or was persistently high over time, with hazard ratios of 1.88 (95% confidence interval 1.37-2.58), 2.32 (1.61-3.35), and 1.94 (1.28-2.94), respectively. In men, those with elevated systolic BP that continued to increase over time had a 50% increased AF risk: 1.51 (1.09-2.10). When compared to those persistently normotensive, women developing hypertension during the exposure period, and women and men with hypertension throughout the exposure period had 1.40 (1.06-1.86), 2.75 (1.99-3.80), and 1.36 (1.10-1.68) times increased risk of AF, respectively. CONCLUSION: Long-term BP and hypertension trajectories were associated with increased incidence of AF in both women and men, but the associations were stronger in women.

Out-patient commitment order use in Norway: incidence and prevalence rates, duration and use of mental health services from the Norwegian Outpatient Commitment Study.

BACKGROUND: Norway authorised out-patient commitment in 1961, but there is a lack of representative and complete data on the use of out-patient commitment orders. AIMS: To establish the incidence and prevalence rates on the use of out-patient commitment in Norway, and how these vary across service areas. Further, to study variations in out-patient commitment across service areas, and use of in-patient services before and after implementation of out-patient commitment orders. Finally, to identify determinants for the duration of out-patient commitment orders and time to readmission. METHOD: Retrospective case register study based on medical files of all patients with an out-patient commitment order in 2008-2012 in six catchment areas in Norway, covering one-third of the Norwegian population aged 18 years or more. For a subsample of patients, we recorded use of in-patient care 3 years before and after their first-ever out-patient commitment. RESULTS: Annual incidence varied between 20.7 and 28.4, and prevalence between 36.5 and 48.9, per 100 000 population aged 18 years or above. Rates differed significantly between catchment areas. Mean out-patient commitment duration was 727 days (s.d. = 889). Use of in-patient care decreased significantly in the 3 years after out-patient commitment compared with the 3 years before. Use of antipsychotic medication through the whole out-patient commitment period and fewer in-patient episodes in the 3 years before out-patient commitment predicted longer time to readmission. CONCLUSIONS: Mechanisms behind the pronounced variations in use of out-patient commitment between sites call for further studies. Use of in-patient care was significantly reduced in the 3 years after a first-ever out-patient commitment order was made. DECLARATION OF INTEREST: None.

Left atrial diameter, left ventricle filling indices, and association with all-cause mortality: Results from the population-based Tromsø Study.

AIMS: To examine the associations between diastolic dysfunction indices and long-term risk of all-cause mortality in adults over 23-year follow-up. METHODS AND RESULTS: Participants (n = 2734) of the population-based Tromsø Study of Norway had echocardiography in 1994-1995. Of these 67% were repeated in 2001 and/or 2007-2008. Mortality between 1994 and 2016 was determined by linkage to the national death registry. Cox regression was used to model the hazard of all-cause mortality in relation to left atrial parameters (treated as time-dependent using repeated measurements) adjusted for traditional risk factors and cardiovascular disease. During the follow-up, 1399 participants died. Indexed left atrial diameter, mitral peak E deceleration time, and mitral peak E to peak A ratio showed an U-shaped association with all-cause mortality. Combining left atrial diameter with mitral peak E deceleration time increased the prognostic accuracy for all-cause mortality whereas adding mitral peak E to peak A ratio did not increase prognostic value. We estimated new optimal cutoff values of left atrial diameter, mitral peak E deceleration time, and mitral peak E to peak A ratio for all-cause mortality outcome. E/e' had a cubic relation to mortality. CONCLUSION: Both enlarged and small left atrial diameters were associated with increased all-cause mortality risk. A combination of Doppler-based left ventricle filling parameters had an incremental effect on all-cause mortality risk. The cutoff values of diastolic dysfunction indices we determined had similar all-cause mortality prediction ability as those recommended by American Association of Echocardiography and European Association of Cardiovascular Imaging.

Sociodemographic characteristics, sexual behaviour and knowledge about cervical cancer prevention as risk factors for high-risk human papillomavirus infection in Arkhangelsk, North-West Russia.

While sociodemographic predictors of cervical cancer (CC) are well understood, predictors of high-risk (HR) human papillomavirus (HPV) infection have not been fully elucidated. This study explored the HR-HPV infection positivity in relation to sociodemographic, sexual behavior characteristics and knowledge about HPV and CC prevention among women who visited the Arkhangelsk clinical maternity hospital named after Samoylova, Russia. This cross-sectional study was conducted in the city of Arkhangelsk, Northwest Russia. Women who consulted a gynecologist for any reason between 1 January 2015 and 30 April 2015 were residents of Arkhangelsk, 25-65 years of age were included. The Mann-Whitney and Pearson's χ2 tests were used. To determine the HR-HPV status, we used the Amplisens HPV-DNA test. We used a questionnaire to collect the information on sociodemographic factors. Logistic regression was applied. The prevalence of HR-HPV infection was 16.7% (n = 50). HR-HPV infection was more prevalent in younger women, cohabiting, nulliparae, smokers, having had over three sexual partners and early age of sexual debut. The odds of having a positive HR-HPV status increased by 25% with an annual decrease in the age of sexual debut. Moreover women with one child or more were less likely to have positive HR-HPV status.

Sex Differences in the Impact of Body Mass Index on the Risk of Future Atrial Fibrillation: Insights From the Longitudinal Population-Based Tromsø Study.

BACKGROUND: Atrial fibrillation (AF) prevalence is increasing, and body mass index (BMI) is a risk factor for AF. However, sex differences in the impact of BMI on AF risk have not been fully elucidated. METHODS AND RESULTS: Data from the fourth survey (1994-1995) of the Tromsø Study (Norway) were used to investigate the association of single-measurement BMI on future AF risk. To analyze the influence of BMI changes on AF risk, data from individuals who attended the third and fourth study surveys were used. AF diagnosis was derived from record linkage and end point adjudication. Cox regression analysis was conducted using fractional polynomials of BMI and BMI change with models adjusted for age, baseline BMI (change analyses), risk factors, comorbidities, and antihypertensive medications.Data were available for 24 799 individuals from the fourth survey (mean age, 45.5±14.2 years; 52.9% women). Over 15.7±5.5 years, 811 women (6.2%) and 918 men (7.9%) developed AF. In men, lower BMI decreased AF risk and higher BMI increased risk (hazard ratios [95% confidence intervals] for BMI 18 or 40 kg/m2 compared with 23 kg/m2 were 0.75 [0.70-0.81] and 4.42 [3.00-6.53], respectively). The same pattern was identified in women. Two surveys were attended by 14 652 individuals. In men and women, a decrease in BMI over time was associated with decreased AF risk and an increase in BMI was associated with increased AF risk. CONCLUSIONS: Within a population cohort, BMI was positively associated with AF risk. Change in BMI over time influenced AF risk in both men and women.

Knowledge about human papillomavirus and prevention of cervical cancer among women of Arkhangelsk, Northwest Russia.

BACKGROUND: Knowledge about cervical cancer (CC) risk factors and benefits of CC prevention motivates women to participate in its screening. However, several studies show that there is a significant knowledge deficit worldwide about human papillomavirus (HPV). The current study explores the level of knowledge about HPV and CC prevention in the context of sociodemographic and behavioral characteristics of women who visited an antenatal clinic in Arkhangelsk, Russia. METHODS: This cross-sectional study was conducted in the city of Arkhangelsk, which seats the administrative center of Arkhangelsk County, Northwest Russia. It included women who consulted a gynecologist for any reason between January 1, 2015 and April 30, 2015, were residents of Arkhangelsk, 25 to 65 years of age and sexually active (N = 300). Student's t-test for continuous variables and Pearson's χ2 test for categorical variables were used in the comparisons of women grouped as having either poor or sufficient knowledge. Linear regression analysis was also employed. RESULTS: The level of knowledge about HPV and CC prevention was associated with education, parity, age of initiating of intercourse, and sources of information. After adjustment, women with university education were more likely to have higher knowledge about HPV and CC prevention compared to those with lower education. CONCLUSIONS: We observed that most participants had a sufficient level of knowledge. Educational gaps were identified that potentially could be used to tailor interventions in CC prevention.

Resting heart rate trajectories and myocardial infarction, atrial fibrillation, ischaemic stroke and death in the general population: The Tromsø Study.

Background Resting heart rate is an established risk factor for cardiovascular disease, but long-term individual resting heart rate trajectories and their effect on cardiovascular disease morbidity and mortality have not yet been described. Methods This large population-based longitudinal study included 14,208 men and women aged 20 years or older, not pregnant and not using blood pressure medications, who attended at least two of the three Tromsø Study surveys conducted between 1986-2001. Resting heart rate was measured using an automated Dinamap device. Participants were followed up from 2001 to 2012 with respect to myocardial infarction, atrial fibrillation, ischaemic stroke, cardiovascular disease death and total death. The Proc Traj statistical procedure was used to identify resting heart rate trajectories. Results Five common long-term resting heart rate trajectories were identified: low, moderate, decreasing, increasing and elevated. In men, an elevated resting heart rate trajectory was independently associated with an increased risk of myocardial infarction when low resting heart rate trajectory was used as a reference (hazard ratio 1.83, 95% confidence interval 1.11-3.02). Risk of total death in men was lowest in the low resting heart rate trajectory group and highest in the increasing and elevated resting heart rate trajectory groups. In women, the association between resting heart rate trajectories and myocardial infarction was similar to that in men, but it was not significant. Conclusions Among the five long-term resting heart rate trajectories we identified, increasing and elevated trajectories were associated with an increased risk of myocardial infarction and total death in men. Our results suggest that changes in long-term individual resting heart rate in the general population may provide additional prognostic information.

Resting heart rate predicts incident myocardial infarction, atrial fibrillation, ischaemic stroke and death in the general population: the Tromsø Study.

BACKGROUND: Elevated resting heart rate (RHR) increases risk of death overall, but a comprehensive picture of the associations between RHR, cardiovascular morbidity and mortality events has not yet been presented. We aimed to investigate the effect of RHR on the risk of 5 cardiovascular events: incident myocardial infarction (MI), incident atrial fibrillation (AF), incident ischaemic stroke, total death and cardiovascular death in a general population from Norway. METHODS: We followed 24 489 men and women from the Tromsø Study 1994-1995, a population-based cohort study, for 18 years, and analysed the association between RHR and the investigated cardiovascular events. Sex-specific Cox regression with time-dependent covariates was applied with the best-fitting fractional polynomials of RHR. RESULTS: Among men, an independent positive relationship was observed for MI and AF (adjusted HR for AF per 20 bpm increase=1.14; 95% CI 1.02 to 1.27). In women, the corresponding HR for MI was 1.23 (1.09 to 1.40). A J-shaped association was observed for ischaemic stroke in women when compared with a RHR of 70 bpm (HR for 50 bpm=1.31; 0.90 to 1.90; HR for 100 bpm=1.32; 1.04 to 1.69). Total and cardiovascular death showed a strong positive association with RHR in men. In women, the pattern for total death was similar. CONCLUSIONS: RHR is an independent risk factor for several cardiovascular events. A novel finding is the positive association between RHR and AF in men and the sex difference in association with ischaemic stroke.

Resting heart rate on the decline: the Tromsø Study 1986-2007.

BACKGROUND: We examined secular changes in resting heart rate (RHR) and their relationship with changes in other cardiovascular risk factors in adult men and women over a 22-year period. METHODS: A single-centre population-based longitudinal study comprised 30,699 men and women aged 30-89 years who participated in at least one of the 1986, 1994, 2001 and 2007 surveys of the Tromsø Study, Tromsø, Norway. RESULTS: During the study period, the age-adjusted means of RHR declined from 73.4 to 64.7 beats per minute (b.p.m.) in men, and from 78.3 to 66.4 b.p.m. in women. The decline was persistent from one survey to the next and was of similar size in both sexes and for all age groups and birth cohorts. RHR declined gradually over time for different levels of cardiovascular risk factors, and it declined more in those who moved from adverse to favourable values or categories of blood pressure, total and high-density lipoprotein cholesterol, triglycerides, body mass index, smoking and physical activity, and those who started to take blood pressure medication. The strongest predictors of individual decline in RHR were decrease in systolic blood pressure and triglycerides, increase in physical activity, taking blood pressure treatment and smoking cessation. CONCLUSION: A considerable decline in RHR has occurred in Tromsø over the past two decades in men and women of all ages. The decline is partly related to changes in several cardiovascular risk factors, and reasons behind this need to be further elucidated. The findings suggest that new definitions of normal RHR may be needed.

Early pregnancy body mass index and spontaneous preterm birth in Northwest Russia: a registry-based study.

BACKGROUND: International studies on the association between maternal body mass index (BMI) and spontaneous preterm birth (PTB) yield controversial results warranting large studies from other settings. The aim of this article was to study association between maternal early pregnancy BMI and the risk of spontaneous PTB in Murmansk County (MC), Northwest Russia. METHODS: This is a registry-based cohort study. All women with singleton pregnancies registered at antenatal clinics during the first 12 weeks of gestation and who delivered in MC between January, 1st 2006 and December, 31st 2011 comprised the study base (n = 29,709). All women were categorized by BMI into four groups: underweight (<18.5 kg/m2), normal (18.5-24.9 kg/m2), overweight (25.0-29. kg/m2), and obese (≥30.0 kg/m2). Multivariable logistic regression was used to study associations between maternal BMI and PTB (<37 weeks) and very preterm birth (VPTB) (<32 weeks) adjusted for socio-economic factors, biological and lifestyle characteristics. RESULTS: The prevalence of underweight, overweight and obesity were 7.1% (95% CI: 6.8-7.4), 18.3% (95% CI: 17.8-18.7) and 7.1% (95% CI: 6.8-7.4), respectively. Altogether, 5.5% (95% CI: 5.3-5.8) of the births were PTB and 0.8% (95% CI: 0.7-0.9) were VPTB. After adjustment, both underweight (OR = 1.25, 95% CI: 1.03-1.50), overweight (OR = 1.10, 95% CI: 0.97-1.26) and obese (OR = 1.31, 95% CI: 1.08-1.57) women were more likely to deliver preterm. VPTB was associated with overweight (OR = 1.47, 95% CI: 1.056-2.03) and obesity (OR = 1.63, 95% CI: 1.02-2.60). CONCLUSION: The findings demonstrate a J-shaped association between first trimester maternal BMI and spontaneous PTB and VPTB with increased risk among underweight, overweight and obese women.