Spinal mobility factors and predicting response to biologic therapy for patients with axial spondyloarthritis

Spinal mobility factors and predicting response to biologic therapy for patients with axial spondyloarthritis

What was this study about?

Axial spondyloarthritis (axSpA) is a joint disease that affects the spine. As part of a patient’s assessment for axSpA the mobility of the spine is commonly measured; this is time consuming and needs to be conducted in-person by trained health care providers

The British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) is a research project which collected spinal mobility data from 1960 people with axSpA across the UK. In addition to this, questionnaires were completed by patients, and clinical data, including disease responses to new ‘biologic’ therapies, were also collected as part of this register.

What was the study looking for?

In this study we tried to determine:

  • Which factors, taken from data routinely collected at patient recruitment, are associated with poor spinal mobility, and
  • Whether spinal mobility collected at recruitment can predict the response to treatment when using ‘biologic’ drugs for the first time.

What did the study find?

The results of the study found that:

  • Approximately three quarters of clinical centres participating to this study routinely measured the spinal mobility in their axSpA patients
  • Using routinely collected ‘factors’, spinal mobility could only be reasonably well estimated in half of the patients studied
  • Poor spinal mobility was predicted using a combination of these ‘factors’:
    • socio-demographic (being older, being male, those not currently employed and those educated at a lower level)
    • clinical (poorer physical function, signs of active inflammation in the lower back, longer duration of symptoms)
    • biological (high CRP levels, meaning signs of inflammation, most probably due to the axSpA condition)
  • Poorer spinal mobility at recruitment predicted a lower effectiveness of the ‘biologic’ drug therapy between 3 to 9 months after the treatment start. Hence, patients with poor spinal mobility were less likely to reduce their disease activity when compared with levels at recruitment. Also, poorer spinal mobility at recruitment predicted poorer quality of life after the treatment with ‘biologics’ drugs.

What is the main message from these results?

This study suggests that while measuring spinal mobility can provide additional information on disease status and, for some measures, of response to treatment, it remains to be determined how this should be incorporated into disease monitoring and clinical decision making, particularly in circumstances where face-to-face consultations are likely to become less frequent.

Who funded this work?

The study was supported by the British Society for Rheumatology, who received funding for this from Pfizer, AbbVie and UCB.

Where can I read more?

You can read the full scientific paper here.