Research questions and objectives
1. Determine if individuals born prematurely are more likely to develop osteoporosis, osteoarthritis and rheumatoid arthritis as adults.
2. For those diseases in which preterm birth is deemed to be a risk factor, begin to explore the proximate causes, such as bone mineral density (osteoporosis) or joint morphology (osteoarthritis).
Scientific rationale
About 10% of all live births worldwide are preterm (gestational age <37 weeks), with resultant short- and long-term health challenges involving multiple organ systems. Since 80% of fetal bone mineral accrual occurs during the third trimester, preterm birth can lead to (i) metabolic bone disease of prematurity, (ii) lower than expected peak bone mass and (iii) increased risk of osteoporosis later in life. Thus, the long-term consequences, although currently not well-explored, may be particularly relevant for the skeletal system. In the U.S., African American and Hispanic populations are disproportionately more likely to have preterm births, meaning that as adults minority populations may be at higher risk for chronic disease. We have performed pilot work using data from the UK Twins Study, in which a subset of the cohort had information about their birth status. For females, individuals with preterm birth were more likely to develop osteoarthritis compared to individuals born at full term (p < 0.039), with a trend in the same direction for rheumatoid arthritis (p = 0.148), and no apparent trend for osteoporosis (p = 0.673). We are currently working on further analyses to consider potential confounding variables. Importantly, there are limitations to the UK Twin study which we believe can be addressed with the UK Biobank, including only a limited sample of very preterm births (gestational age <32 weeks), small sample size for males and reliance on self-reported data for gestational age at birth.
