The association of hemoglobin A1c with the prevalence of stenosing flexor tenosynovitis.

Purpose: Diabetic patients are susceptible to stenosing flexor tenosynovitis (FTS) and may have a diminished response to treatment. The purpose of this study was to determine whether elevated hemoglobin A1c (HbA1c) levels are associated with the development of FTS.

Methods: A review of our diabetic registry identified a cohort of patients with diabetes mellitus. We stratified this cohort to those with and without a diagnosis of FTS during 2008 based on International Classification of Diseases-9 coding (727.00-727.05J). We reviewed charts to confirm the diagnosis. For patients diagnosed with FTS, we used the HbA1c measurement made closest to the date of diagnosis for analysis. We assessed patients without FTS using an average of HbA1c measurements during the same time period and performed subgroup analysis based on specified HbA1c levels (group A, HbA1c level < 7.0%; group B, HbA1c 7.0% to 7.9%; group C, HbA1c 8.0% to 8.9%; group D, HbA1c ≥ 9.0%). Statistical testing consisted of chi-square analysis, odds ratios, and multivariate regression analysis.

Results: There were 259,927 patients in 2008 identified with diabetes mellitus, 3,952 of whom were diagnosed with FTS. The period prevalence of FTS in this diabetic population was 1.5%. Multivariate regression analysis revealed that HbA1c greater than 7% was an independent risk factor for FTS (odds ratio/confidence interval: group B, 1.31/1.20-1.42; group C, 1.35/1.21-1.51; group D, 1.23/1.10-1.38).

Conclusions: The prevalence of FTS in this diabetic population was considerably lower than expected and may represent a more accurate assessment given the power of this population-based study. In addition, the development of FTS appears to be associated with higher HbA1c levels. Although further study is necessary, this association may be relevant when evaluating and treating diabetic patients with trigger finger.