Smoking Effect on Lumbar Intervertebral Disc Degeneration
Condition: Intervertebral Disc Degeneration
MeSH terms: Intervertebral Disc Degeneration
Study type: Observational

Summary: 
      Besides normal aging, genetic and environmental factors are important potential determinants
      of lumbar disc degeneration. Smoking causes serious health problems, particularly lung and
      other cancers, heart disease and respiratory diseases, and is among the most common causes of
      death worldwide. Besides these commonly known diseases related to smoking numerous studies
      have shown that smoking has detrimental effects on the musculoskeletal system and worsens the
      prognosis and treatment of leukomotor diseases. In the literature there are studies examining
      the effect of smoking status on disc degeneration. The aim of the study was to investigate
      the effect of current, former and passive smoking status on degeneration of lumbar
      intervertebral discs.
    

Detailed description: 
      This retrospective study was performed by obtaining medical records of patients who underwent
      lumbar spinal MRI between September 2019 and February 2020. After the application of
      exclusion criteria 955 patients determined between the specified dates. These patients were
      called by phone to be questioned about their smoking status and whether they were working in
      heavy work and whether they were athletes. Heavy workers and athletes were also excluded from
      the study and a total of 360 patients whose smoking status information could be obtained were
      included in the study.The patients were grouped according to their smoking status as "current
      smoker", "former smoker", "non-smoker" and "passive smoker". The cumulative smoking dose for
      current and former smokers was calculated in terms of pack-years and categorized further into
      two subgroups: smoked ≤9 pack-years or >9 pack-years. The number of pack-years was calculated
      by dividing the number of cigarettes consumed per day by 20 and multiplying by the years that
      the patient had smoked. Age, gender, weight, and height were recorded, and body mass index
      (BMI) was calculated as weight/(height)2. Lumbar spinal MRI was performed using a 1.5 Tesla
      imaging system (General Electric Healthcare, Milwaukee, WI), using the following settings:
      amplitude: 44 mT/m; slew rate gradient configuration: 200 T/m/s. MRI images were evaluated
      using a GE Advantage Workstation (GE Healthcare, Buc, France) and Volume Share software
      v.7.0. The lumbar lordosis angle was measured and the lumbar intervertebral discs were
      evaluated by Pfirrmann disc degeneration grading system using sagittal T2-weighted MR images
      (TR/TE: 2500/85 ms, matrix: 320x224, slice thickness: 4 mm, FOV: 32) (23). The degree of
      degeneration was classified into five grades with Grades IV and V considered as "severe disc
      degeneration". Radiologist reviewing the MRI studies was blinded to the smoking status of the
      participants.
    

Observational model: Case-Only
Time perspective: Retrospective
Sampling method: Non-Probability Sample
Study population: 
        Patients who underwent lumbar spinal MRI between September 2019 and February 2020 and
        questioned for smoking status.
      
Keywords: Intervertebral disc degeneration; Magnetic resonance imaging; Smoking; Passive smoker