Does type 2 diabetes mellitus promote intervertebral disc degeneration?
LDD is an important cause of low back pain. Many people believe there is an adverse influence of type 2 diabetes (T2D) on lumbar intervertebral disc degeneration (LDD). We examined a population sample for epidemiological evidence of association.



Twin volunteers from the TwinsUK cohort having spine magnetic resonance (MR) scans coded for LDD and information about T2D were investigated in two ways. First, as a population sample and second as a cotwin case control study in twin pairs discordant for T2D. Other risk factors for LDD considered were age, body-mass index (BMI), smoking, and alcohol.



In 956 twin volunteers T2D had a prevalence of 6.6 %. LDD score was higher in T2D twins (14.9 vs 13.1 p = 0.04) but was not an independent risk factor if the influence of age and BMI were included in the model. Discordant twin analysis (n = 33 pairs) showed no significant difference in LDD between twins having T2D and their unaffected cotwins.



Twins having T2D did manifest higher LDD scores but the effect was abrogated once BMI was included in multivariable analysis, showing it is not an independent risk factor for LDD. The population study had 80 % power at 0.1 significance level to detect a difference of 1.8 in LDD score (range of 0-60), so if there is an effect of T2D on LDD, it is likely to be small.
Department of Twin Research, King's College London, St Thomas' Hospital Campus, 4th Floor South Wing Block D, Westminster Bridge Road, London, SE1 7EH, UK.
Stella Maris
SM
Fabiane
Department of Twin Research, King's College London, St Thomas' Hospital Campus, 4th Floor South Wing Block D, Westminster Bridge Road, London, SE1 7EH, UK.
Kirsten J
KJ
Ward
Leni and Peter W. May Department of Orthopaedics, Icahn School of Medicine at Mount Sinai, 1 Gustave Levy Place, Box 1188, New York, NY, 10029-6574, USA.
James C
JC
Iatridis
Department of Twin Research, King's College London, St Thomas' Hospital Campus, 4th Floor South Wing Block D, Westminster Bridge Road, London, SE1 7EH, UK. frances.williams@kcl.ac.uk.
Frances M K
FM
Williams
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000453:epidemiology; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000453:epidemiology / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014427:Twins; D055815:Young Adult
Lumbar disc disease; Lumbar intervertebral disc degeneration; Type 2 diabetes