Association between cardiovascular risk factors and degenerative disc disease of the thoracolumbar spine in the general population: results from the KORA MRI Study.

BACKGROUND: Little is known about the associations between cardiovascular risk factors (CRF) and disc degeneration (DD). PURPOSE: To evaluate the potential association between CRFs and intervertebral DD in a population-based sample. METHODS: A total of 400 participants from the community-based KORA-study were assessed in terms of CRFs, specifically obesity, hypertension, diabetes, elevated LDL-c, low HDL-c, elevated triglycerides, smoking status, and alcohol consumption. The patients additionally underwent whole-body magnetic resonance imaging (MRI) using T2-weighted single-shot fast-spin-echo and T1 dual-echo gradient-echo Dixon pulse sequences. Thoracic and lumbar DD were assessed using the Pfirrmann score and for the presence of disc bulging/protrusion. Cross-sectional associations between CRFs and MR-based Pfirrmann score were then analyzed. RESULTS: A total of 385 individuals (58.2% men; mean age 56.3 ± 9.2 years) were included. Prevalence of DD was 76.4%. Older age (ß = 0.18; 95% CI 0.12-0.25; P < 0.001) and higher body mass index (BMI) (ß = 0.19; 95% CI 0.06-0.30; P = 0.003) were significantly associated with DD of the thoracolumbar spine. Diabetes was significantly associated with DD at T7/8 (P = 0.029) and L3/4 (P = 0.017). Hypertension correlated significantly with DD in univariate analysis, but the association did not persist using multivariate analysis (ß = 0.53; 95% CI -0.74 to 1.81; P = 0.41). None of the other CRFs (P ≥ 0.11) were associated with advanced DD. Disc bulging was independently associated with hypertension (ß = 0.47; 95% CI 0.27-0.81; P = 0.01). CONCLUSION: A significant independent association exists between age, BMI, and intervertebral DD. In contrast, there is no significant association between cardiovascular risk factors and DD. Providing strong evidence that the pathologic process undergirding DD is mechanical, rather than microvascular, in nature.

Long-term effect of physical inactivity on thoracic and lumbar disc degeneration-an MRI-based analysis of 385 individuals from the general population.

BACKGROUND CONTEXT: The correlation between physical inactivity, thoracolumbar disc degeneration, and back pain remains unclear. PURPOSE: This study investigated the relationship between short- and long-term physical inactivity and degenerative changes of the thoracic and lumbar spine in a southern German cohort from the general population over a time period of 14 years. STUDY DESIGN/SETTING: This study was designed as a cross-sectional case-control study, nested in a prospective cohort from the "Cooperative Health Research in the Region of Augsburg/Kooperative Gesundheitsforschung in der Region Augsburg" (KORA) study. PATIENT SAMPLE: All participants in the population-based KORA study were assessed using a physical activity questionnaire to establish a baseline in 1999-2001 (exam 1), within an initial follow up questionnaire in 2006-2008 (exam 2), and a second follow-up questionnaire between 2013 and 2014 (exam 3). A subsample of this group (400 subjects) underwent full body MR scan performed on a 3T magnetic resonance imaging scanner current with exam 3. OUTCOME MEASURE: Data regarding physical inactivity over a time period of 14 years and back pain, and quantification of thoracic and lumbar disc degeneration on magnetic resonance imaging. METHODS: Quantification of thoracic and lumbar disc degeneration was performed using the Pfirrmann score. Physical activity was grouped as no physical activity, irregularly for 1 hour, regularly for 1 hour, or regularly for ≥2 hours. This was used to calculate another variable "physical inactivity," with the options of irregular activity ≤1 hour per week or regularly ≥1 hour. Physical labor, walking, and cycling activity were additionally investigated. Correlations between physical inactivity measurements and thoracic and lumbar disc degeneration were analyzed via linear regression models adjusted for age, sex, BMI, hypertension, diabetes, and back pain. RESULTS: In total, 385 individuals (mean age: 56 years, SD ± 9.19; 58.2% male) were included in this study. Mean summed Pfirrmann score was 2.41 (SD ± 4.19) in the thoracic and 1.78 (SD ± 1.81) in the lumbar spine. The level of current exercise in our cohort varied with 113 (29.4%) subjects exercising regularly ≥2 hours per week, 118 (30.7%) regularly 1 hour per week, 57 (14%) irregularly for about 1 hour per week, and 97 (25.2%) stated not to exercise at exam 3. Disc degeneration was more apparent in those with irregular activity <1 hour compared to those with regular activity of ≥1 hour and more per week (p<.01) and in those with no activity compared to those with regular activity of ≥2 (p<.001) measured using exam 3. Less physical activity over a time period of 14 years correlated with an increase of disc degeneration of the thoracic and lumbar spine after adjustment for age, sex, BMI, hypertension and diabetes mellitus (p<.05). There was no statistically significant association between physical labor, walking activity, or cycling activity with disc degeneration. Additionally, no significant correlations between degree of disc degeneration (p=.990), degree of physical inactivity (p=.158), and back pain were observed. CONCLUSION: Degree of physical inactivity as measured over a time period of 14 years demonstrated a strong correlation with disc degeneration of the thoracic and lumbar spine.

Association between metabolic syndrome and hip osteoarthritis in middle-aged men and women from the general population.

OBJECTIVE: To investigate the impact of metabolic syndrome and its components on osteoarthritis of the hip joints compared to a healthy cohort in the KORA MRI-study. METHODS: Randomly selected men and women from the general population were classified as having metabolic syndrome, defined as presence of central obesity plus two of the following four components: elevated blood pressure (BP), elevated fasting glucose, elevated triglycerides (TG) and low HDL-cholesterol (HDL-c), or as controls without metabolic syndrome. Therefore, each subject underwent detailed assessment of waist circumference as well as fasting glucose, systolic and diastolic BP, TG, and HDL-c concentrations as well as a full-body MR scan. MR measurements were performed on a 3 Tesla scanner (Magnetom Skyra, Siemens) including a dual-echo Dixon and a T2 SS-FSE sequence for anatomical structures. In order to quantify osteoarthritis of the hip, assessment was performed by two independent, experienced radiologists for joint gap narrowing, osteophytic lipping and subchondral changes (e.g. sclerosis, pseudocysts). Associations between metabolic syndrome components and hip degeneration were estimated by logistic regression models providing odds ratios. RESULTS: Among 354 included participants (mean age: 56.1 ± 9.2 years; 55.4% male), 119 (34%) had metabolic syndrome, while 235 (66%) were part of the control group. Except for elevated blood glucose (p = 0.02), none of the metabolic syndromes' component was independently associated with osteoarthritis. Multivariable adjusted ORs for osteoarthritis of the right hip were 1.00 (95% CI 0.98;1.03), 1.00 (95% CI 0.99;1.00), 1.01 (95% CI 0.99;1.03), 1.00 (95% CI 0.97;1.04) and 1.01 (95% CI 0.96;1.06), and for the left hip 1.00 (95% CI 0.98;1.03), 1.00 (95% CI 1.00;1.01), 1.01 (95% CI 0.99;1.03), 0.99 (95% CI 0.96;1.02) and 1.04 (95% CI 0.99;1.09) for waist circumference, triglyceride, HDL-c and systolic and diastolic BP, respectively. Blood glucose was a borderline non-dependent factor for osteoarthritis of the right hip (OR: 1.02 (95% CI 1.0;1.04); p = 0.05). Furthermore, the compound metabolic syndrome was not significantly associated (OR left hip: 1.53 (95% CI 0.8;2.92), p = 0.20; OR right hip: 1.33 (95% CI 0.72;2.45), p = 0.37) with osteoarthritis of the hip joint. Age as well as gender (left hip) were the only parameters in univariate and multivariate analysis to be significantly associated with osteoarthritis of the hip joint. CONCLUSION: The compound metabolic syndrome showed no association with osteoarthritis of the hip joint. Age was the only parameter to be dependently and independently associated to osteoarthritis of both hip joints, while elevated blood glucose was independently associated with degeneration of the right hip joint.