Lack of association between thyroid status and chondrocalcinosis or osteoarthritis: the Framingham Osteoarthritis Study.

Objective: To assess whether current thyroid status is associated with chondrocalcinosis or osteoarthritis (OA), we examined the cross sectional association of serum thyrotropin (thyroid stimulating hormone, TSH) with chondrocalcinosis and with knee OA in members of the Framingham OA study.

Methods: Knee radiographs were taken at the 18th biennial examination (1983-85) and measurement of serum TSH at either the 15th (1977-79) or the 18th biennial examination. Chondrocalcinosis was dichotomized as absent or present and knee OA was based on a Kellgren and Lawrence score of grade 2 or greater in either knee. Thyroid status was determined by serum TSH concentration classed into clinically relevant categories: < or = 0.1 mU/l(low); > 0.1 < 0.4 mU/l (slightly low); 0.4 to 5.0 mU/l (normal); > 5 < or = 10 mU/l (slightly high); and > 10 mU/l (high).

Results: Data were collected on 577 men and 798 women. We found no association between elevated serum TSH concentration and chondrocalcinosis. Our results, though not statistically significant, suggest an inverse relation, with an odds ratio (OR) of 0.41 (95% CI 0.10, 1.73) for those subjects. in the highest TSH group and 1.79 (95% CI 0.39, 8.24) for those in the lowest TSH group, compared to subjects in the normal range. We found no association between serum TSH concentration and radiographic knee OA, with an OR of 0.85 (95% CI 0.47, 1.51) for those in the highest serum TSH group and 1.51 (95 CI 0.54, 4.22) for those in the lowest TSH group, compared to the normal group. Exclusion of subjects taking thyroid hormone confirmed these null results.

Conclusion: There was no evidence, in a large unselected population of older persons, of a significant association between current thyroid status and either chondrocalcinosis or OA.