A study of the natural history of joint hypermobility using a population-based birth cohort

People with generalised joint hypermobility (GJH) are described as being ‘double-jointed’ because their joints are more flexible and bendy than other people’s. Hypermobility may give advantages such as helping with sport, but some people have pain, weakness, feelings that their joints are going to ‘pop out’ and other uncomfortable sensations, particularly in those who are obese. Symptoms associated with GJH can be severe enough to require referral to hospital rheumatology departments for diagnosis and management.

GJH is common in teenagers: 1 in 10 boys and 1 in 3 girls at aged 14. However, there are many important unanswered questions. The Avon Longitudinal Study of Parents and Children (ALSPAC) has data on hypermobility at age 14 and 17, along with detailed information on pain, other symptoms such as irritable bowel syndrome and anxiety/depression, as well as genetic data which will allow novel analyses of potential confounders such as obesity.

The overall aim of this PhD is to describe the natural history of hypermobility between age 14 and 17, and to identify if change in hypermobility status impacts on symptoms. Specifically:

1. To be the first to describe the natural history of musculoskeletal hypermobility between ages 14 and 17, and to stratify participants into relevant subgroups.
2. To investigate the association between subgroups and pain, and to explore the influence of obesity. This will start with a logistic regression approach and will utilise the genetic risk score for variation in adiposity.
3. To explore clustering of symptoms such as fatigue, irritable bowel syndrome, anxiety/depression and subgroups of hypermobility. This will use CART analysis followed by a hierarchical cluster analysis and K-means clustering.