Dietary factors and the risk of lumbar spinal stenosis: A case–control analysis from the PREFACE study

Background and aims: There is a lack of knowledge on the association of dietary factors and Lumbar Spinal Stenosis (LSS). We evaluated the association of a Mediterranean diet (MD), its major food components and ultra-processed food (UPF) with the risk of LSS. Methods and results: Participants were recruited from the Neurosurgery Department of the IRCCS Neuromed, Italy. The study sample consisted of 156 cases of LSS, and 312 controls matched 1:2 for sex, age (±6 months) and physical activity, without a history or clinical evidence of LSS who were identified from the general population. Adherence to MD was assessed by the Mediterranean Diet Score based on 9 food groups. UPF was defined according to NOVA classification and calculated as the ratio (%) of UPF (g/d) on total food consumed (g/d). In multivariable-adjusted analysis, a 2-point increase in the MD score was not associated with LSS risk (OR: 1.02, 95% CI: 0.72–1.46). An increment of 10 g/d of fruits and nuts, cereals or fish led to lower odds of LSS (OR: 0.97, 95% CI: 0.95–0.99; OR: 0.88, 95% CI: 0.82–0.94; OR: 0.87, 95% CI: 0.76–0.99, respectively). Additionally, 1% increment in the consumption of UPF in the diet was independently associated with higher LSS risk (OR: 1.09, 95% CI: 1.04–1.14). Conclusion: A diet rich in fruits, cereals, fish is associated with lower risk of LSS while a large dietary share of UPF increases the risk of this disease. Further studies with a prospective design and larger sample sizes are warranted.