Table 2.
Association Between Glucosamine and Chondroitin Supplement Use, and C-Reactive Protein, by Form, Formulation, and Dose
| Variable | 1999–2004 |
2005–2010 |
|
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| N (Wgt %) | Age and gender adjusteda |
Multivariable adjustedb |
|
Age and gender adjusteda |
Multivariable adjustedb |
|
|||||
| Ratio | 95% CI | Ratio | 95% CI | N (Wgt %) | Ratio | 95% CI | Ratio | 95% CI | p-interaction | ||
| Overall use variables | |||||||||||
| Glucosamine | |||||||||||
| No use | 9542 (95.4) | 1 | REF | 1 | REF | 11,423 (94.6) | 1 | REF | 1 | REF | 0.04 |
| Use | 389 (4.6) | 0.84 | 0.73–0.96 | 0.87 | 0.79–0.96 | 563 (5.4) | 0.98 | 0.83–1.16 | 1.09 | 0.94–1.28 | |
| Chondroitin | |||||||||||
| No use | 9665 (97.0) | REF | REF | REF | REF | 11,571 (96.0) | 1.00 | REF | 1 | REF | 0.01 |
| Use | 266 (3.0) | 0.78 | 0.67–0.90 | 0.83 | 0.72–0.95 | 415 (4.0) | 1.05 | 0.87–1.27 | 1.16 | 0.99–1.35 | |
| Use, by supplement formulation | |||||||||||
| Glucosamine+chondroitin | |||||||||||
| Use of neither | 9540 (95.4) | 1 | REF | 1 | REF | 11,413 (94.6) | 1 | REF | 1 | REF | 0.03 |
| Use of glucosamine alone | 125 (1.6) | 0.96 | 0.75–1.23 | 0.96 | 0.80–1.14 | 158 (1.5) | 0.83 | 0.61–1.13 | 0.95 | 0.74–1.22 | |
| Use of both | 264 (3.0) | 0.78 | 0.67–0.90 | 0.82 | 0.72–0.95 | 405 (3.9) | 1.05 | 0.87–1.26 | 1.16 | 1.00–1.35 | |
| Both versus glucosamine alonec | p: 0.05 | p: 0.12 | p: 0.18 | p: 0.08 | |||||||
| Use, by supplement form | |||||||||||
| Glucosamine | |||||||||||
| No use | 9540 (96.6) | 1 | REF | 1 | REF | 11,413 (95.2) | 1 | REF | 1 | REF | 0.05 |
| Use of glucosamine sulfate | 131 (1.6) | 0.76 | 0.57–1.02 | 0.78 | 0.64–0.95 | 92 (1.0) | 1.10 | 0.73–1.66 | 1.20 | 0.91–1.57 | |
| Use of glucosamine HCl | 154 (1.8) | 0.88 | 0.68–1.12 | 0.87 | 0.72–1.05 | 395 (3.8) | 0.99 | 0.81–1.19 | 1.09 | 0.89–1.32 | |
| Glucosamine HCl versus glucosamine sulfated | p: 0.54 | p: 0.21 | p: 0.56 | p: 0.38 | |||||||
| Use, by supplement dose (among users) | |||||||||||
| Glucosamine dose (mg) | |||||||||||
| Use, <800 | 231 (59.9) | 1 | REF | 1 | REF | 271 (48.7) | 1 | REF | 1 | REF | 0.55 |
| Use, 800 to <1200 | 68 (22.1) | 0.86 | 0.56–1.33 | 1.08 | 0.78–1.48 | 92 (15.1) | 0.83 | 0.55–1.24 | 0.93 | 0.70–1.24 | |
| Use, 1200+ | 73 (18.1) | 0.85 | 0.61–1.20 | 1.01 | 0.79–1.26 | 197 (36.2) | 1.13 | 0.88–1.45 | 1.13 | 0.93–1.37 | |
| p-trend: 0.29 | p-trend: 0.88 | p-trend: 0.37 | p-trend: 0.24 | ||||||||
| Chondroitin dose (mg) | |||||||||||
| Use, <500 | 147 (55.2) | 1 | REF | 1 | REF | 163 (41.4) | 1 | REF | 1 | REF | 0.63 |
| Use, 500 to <1000 | 63 (3.07) | 0.90 | 0.64–1.28 | 1.08 | 0.85–1.39 | 115 (27.3) | 0.96 | 0.67–1.38 | 0.87 | 0.63–1.20 | |
| Use, 1000+ | 40 (14.1) | 1.28 | 0.94–1.74 | 1.27 | 0.95–1.69 | 122 (31.3) | 0.99 | 0.70–1.41 | 0.95 | 0.71–1.28 | |
| p-trend: 0.42 | p-trend: 0.11 | p-trend: 0.95 | p-trend: 0.71 | ||||||||
| Use, by duration (among users) | |||||||||||
| Glucosamine (years) | |||||||||||
| ≤1 year | 188 (47.8) | 1 | REF | 1 | REF | 206 (32.8) | 1 | REF | 1 | REF | 0.04 |
| >1 to ≤4 years | 129 (34.3) | 1.02 | 0.71–1.48 | 1.16 | 0.88–1.53 | 152 (27.9) | 0.88 | 0.58–1.33 | 0.91 | 0.64–1.28 | |
| >4 years | 71 (18.0) | 0.78 | 0.57–1.06 | 0.92 | 0.69–1.23 | 205 (39.4) | 0.79 | 0.54–1.16 | 0.89 | 0.62–1.26 | |
| p-trend: 0.26 | p-trend: 0.92 | p-trend: 0.22 | p-Trend: 0.49 | ||||||||
| Chondroitin (years) | |||||||||||
| ≤1 year | 123 (46.7) | 1 | REF | 1 | REF | 142 (31.7) | 1 | REF | 1 | REF | 0.32 |
| >1 to ≤3 years | 80 (30.2) | 1.06 | 0.68–1.66 | 1.34 | 0.92–1.82 | 94 (22.4) | 0.84 | 0.54–1.31 | 0.84 | 0.57–1.22 | |
| >4 years | 61 (23.1) | 0.83 | 0.59–1.15 | 1.00 | 0.72–1.40 | 169 (45.9) | 0.77 | 1.08–2.08 | 0.78 | 0.57–1.06 | |
| p-trend: 0.39 | p-trend: 0.77 | p-trend: 0.16 | p-trend: 0.12 | ||||||||
Adjusted for age (25–39, 40–49, 50–59, 60–69, 70–79, and 80+) and gender.
Adjusted for gender, age (25–39, 40–49, 50–59, 60–69, 70–79, and 80+), race/ethnicity (non-Hispanic white, non-Hispanic black, Mexican American, and other), education (less than high school, high school grad or equivalent, some college or AA degree, and college grad or above), smoking (never, former, ≤15 cigarettes/day if current, and >15 cigarettes/day if current), BMI (underweight/normal, overweight, obese, and severely obese), physical activity (none, any moderate, and any vigorous), any prescription NSAID use, any prescription steroid use, any non-MVMM vitamin E use, alcohol intake (<1 drink/month, ≥1 drink/month to <4 drinks/week, ≥4 drinks/week to <2 drinks/day, and ≥2 times/day), coffee intake (quartiles), fiber intake (quartiles), saturated fat intake (quartiles), dietary omega-3 intake (quartiles), any non-MVMM omega-3 supplement use, dietary omega-6 intake (quartiles), statin use, cancer, diabetes, heart disease, arthritis, and survey cycle.
p-Value estimated directly comparing users of glucosamine alone with users of glucosamine+chondroitin, in a model restricted to users.
p-Value estimated directly comparing users of glucosamine sulfate with users of glucosamine hydrochloride, in a model restricted to users.
BMI, body mass index; MVMM, multivitamin, multimineral; NSAID, nonsteroidal anti-inflammatory drug.