Body mass index is associated with lumbar disc degeneration in young Finnish males: subsample of Northern Finland birth cohort study 1986

Abstract

BackgroundThe role of environmental factors in lumbar intervertebral disc degeneration (DD) in young adults is largely unknown. Therefore, we investigated whether body mass index (BMI), smoking, and physical activity are associated with lumbar DD among young adults.MethodsThe Oulu Back Study (OBS) is a subpopulation of the 1986 Northern Finland Birth Cohort (NFBC 1986) and it originally included 2,969 children. The OBS subjects received a postal questionnaire, and those who responded (N = 1,987) were invited to the physical examination. The participants (N = 874) were invited to lumbar MRI study. A total of 558 young adults (325 females and 233 males) underwent MRI that used a 1.5-T scanner at the mean age of 21. Each lumbar intervertebral disc was graded as normal (0), mildly (1), moderately (2), or severely (3) degenerated. We calculated a sum score of the lumbar DD, and analyzed the associations between environmental risk factors (smoking, physical activity and weight-related factors assessed at 16 and 19 years) and DD using ordinal logistic regression, the results being expressed as cumulative odds ratios (COR). All analyses were stratified by gender.ResultsOf the 558 subjects, 256 (46%) had no DD, 117 (21%) had sum score of one, 93 (17%) sum score of two, and 92 (17%) sum score of three or higher. In the multivariate ordinal logistic regression model, BMI at 16 years (highest vs. lowest quartile) was associated with DD sum score among males (COR 2.35; 95% CI 1.19-4.65) but not among females (COR 1.29; 95% CI 0.72-2.32). Smoking of at least four pack-years was associated with DD among males, but not among females (COR 2.41; 95% CI 0.99-5.86 and 1.59; 95% 0.67-3.76, respectively). Self-reported physical activity was not associated with DD.ConclusionsHigh BMI at 16 years was associated with lumbar DD at 21 years among young males but not among females. High pack-years of smoking showed a comparable association in males, while physical activity had no association with DD in either gender. These results suggest that environmental factors are associated with DD among young males.

Nonoperative Management of Discogenic Back Pain

“…Studies have shown that obesity and smoking are important risk factors for disc degeneration. 50–52 Thus, the selection criteria in this study potentially excluded an important subset of discogenic pain patients. 49 Biacuplasty may be an effective treatment for disc pain; however, it is unclear whether this therapy is effective for patients with comorbidities such as obesity and smoking that are associated with accelerated disc degeneration.…”

Association between adolescent sport activities and lumbar disk degeneration among young adults

“…BMI data were also available at 18 years as self-reported values through a questionnaire, but BMI at 16 years was selected because BMI at 16 years was more strongly associated with DD in univariate analyses than BMI at 18 or 19 years. 25 Smoking was presented as number of pack-years of smoking and was calculated by multiplying the number of packs of cigarettes smoked daily by years of smoking at the age of 19. Fifteen cigarettes were considered one pack, because we assume smoking is underreported.…”

“…24 We have earlier reported that smoking and body mass index (BMI) were associated with lumbar DD in the same study population. 25 Although socioeconomic status has not been associated with lumbar DD, it is associated with low back symptoms and is therefore justified as a confounding factor. 26 Among Finnish adolescents, physical activity is far more common at a noncompetitive level than participation in competitive sports (84% vs 16%).…”

Semiautomatic classification of intervertebral disc degeneration in magnetic resonance images of the spine

“…Environmental factors such as smoking, obesity, trauma, excessive physical activity or physical inactivity may enhance the development of disc degeneration [2].…”