Physical activity and cognitive function in adults born very preterm or with very low birth weight-an individual participant data meta-analysis

OBJECTIVE

Individuals born very preterm (<32 weeks of gestation) or with very low birthweight (<1500g) have lower cognitive function compared with term-born peers. Furthermore, some studies suggest that they are less physically active as young adults than controls, but the relationship between physical activity and cognitive function remains unclear. We performed an individual participant data meta-analysis to examine whether being born preterm/with very low birth weight is associated with physical activity in adulthood and examined if cognitive function mediates this association.

STUDY DESIGN

Cohorts with data on physical activity and cognitive function in adults born very preterm/very low birth weight and term-born controls were recruited from the Research on European Children and Adults Born Preterm, and the Adults Born Preterm International Collaboration Consortia. A systematic literature search was performed in PubMed and Embase.

RESULTS

Five cohorts with 1644 participants aged 22-28 years (595 very preterm/very low birth weight and 1049 controls) were included. Adults born very preterm/very low birth weight reported 1.11 (95% CI: 0.68 to 1.54) hours less moderate to vigorous physical activity per week than controls, adjusted for cohort, age and sex. The difference between individuals born very preterm/very low birth weight and controls was larger among women than among men. Neither intelligence quotient nor self-reported executive function mediated the association between very preterm/very low birth weight and moderate to vigorous physical activity. Results were essentially the same when we excluded individuals with neurosensory impairments.

CONCLUSION

Adults born very preterm/very low birth weight, especially women, reported less moderate to vigorous physical activity than their term-born peers. Cognitive function did not mediate this association. Considering the risk of adverse health outcomes among individuals born preterm, physical activity could be a target for intervention.

Visual function in adults born preterm with very low birth weight-A two-country birth cohort study

PURPOSE

The purpose of the study was to investigate visual function and vision-related general health in adults that were born preterm with very low birth weight (VLBW: birth weight < 1500 g) in their 30s-40s.

METHODS

We recruited 137 adults born preterm with VLBW and 158 term-born controls aged 31-43 years from two birth cohorts: the Helsinki Study of Very Low Birth Weight Adults (Finland) and the NTNU Low Birth Weight in a Lifetime Perspective study (Norway). We used neonatal data and measured refraction, best-corrected visual acuity (BCVA) using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart, contrast sensitivity, visual fields, intraocular pressure (IOP), self-reported vision-targeted health status with the National Eye Institute Visual Function Questionnaire-25.

RESULTS

VLBW adults had a lower BCVA ETDRS score than controls: mean (SD) better eye 86.7 (13.4) versus 90.2 (4.4), p = 0.02; mean (SD) worse eye 82.3 (14.9) versus 87.6 (4.6), p = 0.003. VLBW adults also had lower contrast sensitivity thresholds in several spatial frequencies and scored lower than controls in eight out of the 12 subscales of self-reported vision-targeted health status. Refraction, visual fields and IOP were similar between groups. Two VLBW participants were blind. None had been treated for retinopathy of prematurity.

CONCLUSION

We suggest that lower visual function and vision-related health represent life-long consequences of prematurity and VLBW in the studied 31- to 43-year-old cohort. The underlying mechanisms remain to be determined.

Mental health, pain and tiredness in adults born very preterm or with very low birthweight

AIM

Adults born preterm have increased risk of mental health problems and other neurodevelopmental conditions. We aimed to investigate associations of mental health with pain and tiredness in adults born very preterm (VP; <32 weeks) or very low birthweight (VLBW; <1500 g) and at term, and whether these associations are influenced by physical activity.

METHODS

As part of an EU Horizon 2020 project, individual participant data from six prospective cohort studies were harmonised for 617 VP/VLBW and 1122 term-born participants. Mental health was assessed by the Achenbach System of Empirically Based Assessment Adult Self-Report. Pain and tiredness were harmonised based on specific items from self-reported questionnaires. Associations between mental health and pain or tiredness were explored by linear regression.

RESULTS

An increase in the mental health scales internalising, externalising and total problems was associated with increased pain and tiredness in the preterm and term group alike. Results were maintained when adjusting for physical activity.

CONCLUSION

The findings indicate that associations between mental health, pain and tiredness in adults are independent of gestation or birthweight. Future research should explore other potential mechanisms that may underlie the increased risk of mental health problems in the preterm population.

Physical activity and associations with health-related quality of life in adults born small for gestational age at term: a prospective cohort study

BACKGROUND

Adults born small for gestational age (SGA) have increased risk of adverse health outcomes. Physical activity (PA) is a key determinant of health and health-related quality of life (HRQoL). We aimed to investigate if being born SGA at term is associated with lower objectively measured and self-reported PA during adulthood. We also examined if objectively measured and self-reported PA were associated with HRQoL.

METHODS

As part of the 32-year follow-up in the NTNU Low Birth Weight in a Lifetime Perspective study, SGA and non-SGA control participants wore two tri-axial accelerometers for seven days (37 SGA, 43 control), and completed the International Physical Activity Questionnaire (IPAQ) (42 SGA, 49 control) and the Short Form 36 Health Survey (SF-36) (55 SGA, 67 control). Group differences in objectively measured daily metabolic equivalent of task (MET) minutes spent sedentary (lying, sitting), on feet (standing, walking, running, cycling), on the move (walking, running, cycling) and running/cycling, and group differences in self-reported daily MET minutes spent walking and in moderate and vigorous PA were examined using linear regression. Associations with SF-36 were explored in a general linear model.

RESULTS

Mean (SD) daily MET minutes on the move were 218 (127) in the SGA group and 227 (113) in the control group. There were no group differences in objectively measured and self-reported PA or associations with HRQoL. In the SGA group, one MET minute higher objectively measured time on the move was associated with 4.0 (95% CI: 0.6-6.5, p = 0.009) points higher SF-36 physical component summary.

CONCLUSION

We found no differences in objectively measured and self-reported PA or associations with HRQoL between term-born SGA and non-SGA control participants in adulthood.