Bone health in young adult survivors born extremely preterm or extremely low birthweight in the post surfactant era

Haikerwal, Anjali<sup>1,2</sup>; Doyle, Lex W.<sup>1,2,3,4</sup>; Patton, George<sup>4,5</sup>; Garland, Suzanne M.<sup>3,6,7</sup>; Cheung, Michael M.<sup>4,8,9</sup>; Wark, John D.<sup>9,11</sup>; Cheong, Jeanie L. Y.<sup>1,2,3</sup>

Affiliations

¹Newborn Services, The Royal Women's Hospital, Melbourne, Australia

²Clinical Sciences, Murdoch Children's Research Institute, Melbourne, Australia

³Department of Obstetrics and Gynecology, The Royal Women's Hospital, The University of Melbourne, Melbourne, Australia

⁴Department of Paediatrics, The University of Melbourne, Melbourne, Australia

⁵Centre for Adolescent Health, Royal Children's Hospital, Melbourne, Australia

⁶Centre for Women's Infectious Diseases Research, The Royal Women's Hospital, Parkville, Australia

⁷Infection & Immunity Theme, Murdoch Children's Research Institute, Parkville, Australia

⁸Heart Research, Murdoch Children's Research Institute, Melbourne, Australia

⁹Department of Cardiology, Royal Children's Hospital, Melbourne, Australia

¹⁰Department of Medicine, The Royal Melbourne Hospital, The University of Melbourne, Melbourne, Australia

¹¹Bone and Mineral Medicine, The Royal Melbourne Hospital, Melbourne, Australia

Abstract and keywords

Background: Most infants born extremely preterm (EP; <28 weeks' gestation) or extremely low birthweight (ELBW; <1000 g birthweight) in the post surfactant era (early 1990s) are now surviving into adulthood. Preterm birth/low birthweight are risk factors for reduced bone growth and mineralisation in infants and children. However, little is known about their bone health around peak bone mass and through adult life.

Objective: To compare bone health (bone mineral measures, bone structure and strength) in young adults born EP/ELBW with controls (>2499 g birthweight), and within the EP/ELBW group examine perinatal and later variables associated with long term bone health.

Methods: A geographic cohort comprising all 297 survivors born EP/ELBW in 1991–92 in the state of Victoria, Australia, and 260 contemporaneous controls (>2499 g birthweight) were recruited into a longitudinal study from birth. At age 25 years, investigations included dual energy X ray absorptiometry and peripheral quantitative computed tomography to measure bone, muscle and soft tissue variables, and fasting blood samples to measure serum 25 hydroxyvitamin D (25(OH)D) and bone turnover markers (BTM). Linear regression analysis, with models fitted using generalised estimating equations, was used to compare outcomes between groups, adjusting for height and weight.

Results: Compared with controls (n = 129), young adults born EP/ELBW (n = 162) had lower areal bone mineral density (g/cm²) (mean difference [MD] −0.044; 95% confidence interval [CI] −0.076,−0.013) and Z-scores (MD −0.53; 95% CI −0.75, −0.30) in the femoral neck, and lower total hip Z-score (MD −0.35; 95% CI −0.54, −0.15) after adjusting for height and weight. EP/ELBW males generally displayed more bone and soft tissue deficits than females, compared with their respective controls. Within the EP/ELBW group, early growth, male sex, height and lean mass, muscle measures, 25(OH)D levels, and BTM were independently associated with bone mineral measures, structure or strength.

Conclusions: Young adults born EP/ELBW had evidence of impaired bone health around the age of peak bone mass compared with controls. Further follow-up of the EP/ELBW groups will determine if they have a heightened low-trauma fracture risk in later life.

Keywords: Bone mineral measures; Bone structure and strength; Vitamin D; Bone turnover markers; Extremely preterm; Young adult

Links

DOI: 10.1016/j.bone.2020.115648

PubMed: 32950698

WoS: 000604734500005

History

Received: 2020-07-1

Revised: 2020-09-12

Accepted: 2020-09-12

Online: 2020-09-17

Cited Works (1)

Year	Entry
2011	Sheu Y, Zmuda JM, Boudreau RM, Petit MA, Ensrud KE, Bauer DC, Gordon CL, Orwoll ES, Cauley JA; Osteoporotic Fractures in Men (MrOS) Research Group. Bone strength measured by peripheral quantitative computed tomography and the risk of nonvertebral fractures: the osteoporotic fractures in men (MrOS) study. J Bone Miner Res. January 2011;26(1):63-71.

Cited By (2)

Year	Entry
2023	Kuitunen I, Sund R, Sankilampi U. Association of preterm birth and low birthweight with bone fractures during childhood. J Bone Miner Res. August 2023;38(8):1116-1124.
2023	Dao T, Robinson DL, Doyle LW, Lee PVS, Olsen J, Kale A, Cheong JLY, Wark JD. Quantifying bone strength deficits in young adults born extremely preterm or extremely low birth weight. J Bone Miner Res. December 2023;38(12):1800-1808.