There are many factors that make an individual vulnerable to lower back pain, including age, trauma, genetics, occupation, and others. Weight is frequently viewed as being associated with a higher frequency of lower back pain, and this is particularly true for those who fall into the category of being obese. A recent study set out to determine whether or not obesity is an independent risk factor for lower back pain, and if so, what level of obesity presents the greatest level of concern.
The study was conducted using information from the Osteoarthritis Initiative database that had previously been collected as part of an inquiry on arthritis of the knee. Although the data had not been collected for the purpose of investigating obesity and lower back pain prevalence, the survey used in the study had included questions that assessed how common lower back pain was, how severe, and how frequently it was experienced. The survey had included responses from about 4,800 participants with an average age of 61 and a gender breakdown of 60% women.
The analysis of the information gathered by the initial researchers revealed that there was a clear contrast in the prevalence of lower back pain between those who were at normal weight and those who were not. Where 48% of those with a BMI of less than 25 indicated that they’d had lower back pain in the 30 days prior to the study, 73% of those who were morbidly obese (with a BMI over 40) had lower back pain. As BMI increased, so too did prevalence of discomfort, though the association between increasing BMI and increasing severity of pain was not significant, and there was no link between increasing BMI and the frequency of lower back pain. The most notable determination was that the strongest predictor of a patient experiencing lower back pain within the previous 30 days was having a BMI of greater than 25.
The authors of the study indicated that their study’s results did not indicate that obesity was a cause of lower back pain, and went on to demonstrate a complex relationship between the two, noting that it was worth considering whether lower back pain may, in fact, contribute to obesity as a result of discomfort limiting patients’ activities and interest in taking part in exercise. The study also pointed to the impact that depression plays in both obesity and lower back pain, and that the three could all have a cause and effect relationship on each other.
The only way to get an accurate assessment of the role that obesity plays on lower back pain would be to follow a large cohort from a young age to determine whether those who eventually become obese are at greater risk for developing lower back pain. Perhaps more importantly, a study of whether losing weight would help reduce the incidence of lower back pain would prove helpful to our spine pain practice as we work to help our patients overcome discomfort and improve the quality of their lives.