Higher BMI is a Persistent Risk Factor for Back Pain Across Adulthood

Takeaway

• Higher body mass index (BMI) and waist circumference (WC) were consistently associated with an increased risk of back pain between ages 36 and 68 years.
• BMI was more strongly related to back pain than WC.

Why this matters

• Findings highlight the importance of intervention to prevent excessive weight gain and reduce overweight and obesity across adulthood in order to help prevent back pain and its disabling consequences as individuals age.

Study design

• British birth cohort study of 3426 (1723 men and 1703 women) participants from the MRC National Survey of Health and Development.
• Back pain was self-reported during nurse interviews at ages 36, 43, 53 and 60-64 years and in a postal questionnaire at age 68 years.
• Funding: UK Medical Research Council.

Key results

• Higher BMI was consistently associated with an increased risk of back pain across adulthood.
• Sex-adjusted ORs (95% CI) of back pain per 1 standard deviation (SD) increase in BMI were:
  • 36 years: 1.13 (1.01-1.26); P=.03;
  • 43 years: 1.11 (1.00-1.23); P=.06;
  • 53 years: 1.17 (1.05-1.30); P=.003;
  • 60-64 years: 1.31 (1.15-1.48); P<.001; and
  • 68 years: 1.08 (0.95-1.24); P=.2.
• Sex-adjusted ORs (95% CI) of back pain per 1 SD increase in WC were:
  • 36 years: 1.17 (1.05-1.31); P=.005;
  • 43 years: 1.12 (1.01-1.24); P=.03;
  • 53 years: 1.16 (1.05-1.29); P=.005;
  • 60-64 years: 1.27 (1.12-1.44); P<.001; and
  • 68 years: 1.12 (0.98-1.27); P=.1.
• These associations were maintained after adjustment for confounders, including education, occupational class, height, cigarette smoking status, physical activity and symptoms of anxiety and depression.
• In a model including both variables, the association of BMI with back pain (OR per SD [95% CI]: 1.11 [0.99-1.24]) at 36, 43, 53 and 68-69 years and 1.28 [1.09 -1.50] at 60-64 years) was stronger than that for WC (OR per SD [95% CI]: 1.02 [0.91 1.13]) at all ages.

Limitations

• Risk of bias.
• Residual confounding.

This clinical summary originally appeared on Univadis, part of the Medscape Professional Network.