Kevin Gil | UEES - Academia.edu (original) (raw)

Papers by Kevin Gil

Spine, 1995

Historical cohort, including selected subgroups. To understand the long-term effects of exercise ... more Historical cohort, including selected subgroups. To understand the long-term effects of exercise on back-related outcomes, back pain, sciatica, back-related hospitalizations, pensions, and magnetic resonance imaging findings were studied among former elite athletes. Exercise and sports participation have become increasingly popular, as have recommendations of exercises for back problems, but little is known about their long-term effects. Questionnaires were returned by 937 former elite athletes and 620 control subjects (83% response rate). Identification codes allowed record linkage to hospital discharge and pension registers. Magnetic resonance images were obtained of selected subgroups with contrasting physical loading patterns. Odds ratios for back pain were lower among athletes than among control subjects, with significant differences in endurance, sprinting and game sports, and wrestling and boxing. No differences in the occurrence of sciatica or in back-related pensions and hospitalizations were seen. When comparing lumbar magnetic resonance images of 24 runners, 26 soccer players, 19 weight lifters, and 25 shooters, disc degeneration and bulging were most common among weight lifters; soccer players had similar changes in the L4-S1 discs. No significant differences were seen in the magnetic resonance images of runners and shooters. Maximal weight lifting was associated with greater degeneration throughout the entire lumbar spine, and soccer with degeneration in the lower lumbar region. No signs of accelerated disc degeneration were found in competitive runners. However, back pain was less common among athletes than control subjects and there were no significant differences in hospitalizations or pensions. No benefits were shown for vigorous exercise compared with lighter exercise with respect to back findings.

Arthritis & Rheumatism, 2009

To examine the allelic diversity of structural, inflammatory, and matrix-modifying gene candidate... more To examine the allelic diversity of structural, inflammatory, and matrix-modifying gene candidates and their association with disc degeneration. Subjects were 588 men ages 35-70 years. We investigated associations of single-nucleotide polymorphisms in AGC1 and in 12 collagen, 8 interleukin, and 4 matrix metalloproteinase genes with quantitative magnetic resonance imaging measurements of disc desiccation and disc bulging and height narrowing scores, after controlling for age and suspected risk factors. Analyses were performed using QTDT software. P values were derived from 1,000 permutations, and empirical P values for global significance also were applied. Twelve of the 99 variants in 25 selected candidate genes provided evidence of association (P < 0.05) with disc signal intensity in the upper and/or lower lumbar regions. Allelic variants of AGC1 (rs1042631; P = 0.001), COL1A1 (rs2075555; P = 0.005), COL9A1 (rs696990; P = 0.00008), and COL11A2 (rs2076311; P = 0.018) genes provided the most significant evidence of association with disc signal intensity. The same variants of AGC1 (P = 0.010) and COL9A1 (P = 0.014), as well as variants in the COL11A1 gene (rs1463035 [P = 0.004]; rs1337185 [P = 0.015]) were also associated with disc bulging, as was AGC1 with disc height narrowing (rs1516797; P = 0.005). In addition, 4 allelic variants in the immunologic candidate genes (rs2071375 in IL1A [P = 0.027]; rs1420100 in IL18RAP [P = 0.005]) were associated with disc signal intensity. Genetic variants account for interindividual differences in disc matrix synthesis and degradation. The accuracy of the quantitative disc signal intensity measurements we used likely enhanced our ability to observe these associations. Our findings shed light on possible mechanisms of degeneration and support the view that disc degeneration is a polygenetic condition.

Spine, 1995

Historical cohort, including selected subgroups. To understand the long-term effects of exercise ... more Historical cohort, including selected subgroups. To understand the long-term effects of exercise on back-related outcomes, back pain, sciatica, back-related hospitalizations, pensions, and magnetic resonance imaging findings were studied among former elite athletes. Exercise and sports participation have become increasingly popular, as have recommendations of exercises for back problems, but little is known about their long-term effects. Questionnaires were returned by 937 former elite athletes and 620 control subjects (83% response rate). Identification codes allowed record linkage to hospital discharge and pension registers. Magnetic resonance images were obtained of selected subgroups with contrasting physical loading patterns. Odds ratios for back pain were lower among athletes than among control subjects, with significant differences in endurance, sprinting and game sports, and wrestling and boxing. No differences in the occurrence of sciatica or in back-related pensions and hospitalizations were seen. When comparing lumbar magnetic resonance images of 24 runners, 26 soccer players, 19 weight lifters, and 25 shooters, disc degeneration and bulging were most common among weight lifters; soccer players had similar changes in the L4-S1 discs. No significant differences were seen in the magnetic resonance images of runners and shooters. Maximal weight lifting was associated with greater degeneration throughout the entire lumbar spine, and soccer with degeneration in the lower lumbar region. No signs of accelerated disc degeneration were found in competitive runners. However, back pain was less common among athletes than control subjects and there were no significant differences in hospitalizations or pensions. No benefits were shown for vigorous exercise compared with lighter exercise with respect to back findings.

Arthritis & Rheumatism, 2009

To examine the allelic diversity of structural, inflammatory, and matrix-modifying gene candidate... more To examine the allelic diversity of structural, inflammatory, and matrix-modifying gene candidates and their association with disc degeneration. Subjects were 588 men ages 35-70 years. We investigated associations of single-nucleotide polymorphisms in AGC1 and in 12 collagen, 8 interleukin, and 4 matrix metalloproteinase genes with quantitative magnetic resonance imaging measurements of disc desiccation and disc bulging and height narrowing scores, after controlling for age and suspected risk factors. Analyses were performed using QTDT software. P values were derived from 1,000 permutations, and empirical P values for global significance also were applied. Twelve of the 99 variants in 25 selected candidate genes provided evidence of association (P < 0.05) with disc signal intensity in the upper and/or lower lumbar regions. Allelic variants of AGC1 (rs1042631; P = 0.001), COL1A1 (rs2075555; P = 0.005), COL9A1 (rs696990; P = 0.00008), and COL11A2 (rs2076311; P = 0.018) genes provided the most significant evidence of association with disc signal intensity. The same variants of AGC1 (P = 0.010) and COL9A1 (P = 0.014), as well as variants in the COL11A1 gene (rs1463035 [P = 0.004]; rs1337185 [P = 0.015]) were also associated with disc bulging, as was AGC1 with disc height narrowing (rs1516797; P = 0.005). In addition, 4 allelic variants in the immunologic candidate genes (rs2071375 in IL1A [P = 0.027]; rs1420100 in IL18RAP [P = 0.005]) were associated with disc signal intensity. Genetic variants account for interindividual differences in disc matrix synthesis and degradation. The accuracy of the quantitative disc signal intensity measurements we used likely enhanced our ability to observe these associations. Our findings shed light on possible mechanisms of degeneration and support the view that disc degeneration is a polygenetic condition.