Intra-articular corticosteroid injection (CSI) is a conservative procedure used in shoulder pain patients to provide rapid relief of shoulder pain. While previous research has shown injections can induce or exacerbate hyperglycemia in patients with uncontrolled diabetes, these studies did not track patients on a daily basis or for longer than seven days. This makes it difficult for clinicians to advise patients on the time period they should monitor their blood glucose levels (BGLs) with increased caution. Hence, this study aimed to observe BGLs in patients with uncontrolled diabetes for 14 days post shoulder CSI.
We recruited 20 patients with either type I or type II diabetes undergoing treatment for a single glenohumeral CSI. All patients had an HbA1C measurement within the last 3 months. All injections were standardized to a total injection volume of 6 mL, comprised of 5 mL 1% Lidocaine (without epinephrine) and 1 mL of Triamcinolone (40mg/mL). We excluded patients that had a prior CSI or had taken oral steroids 6 weeks prior to their injection date. We obtained baseline measure of BGLs using a glucometer prior to the CSI. Subsequently, we had patients record their BGLs using the glucometer and a diary daily for the first week post CSI, and then every other day for the second week. Descriptive statistics were performed to determine a normal distribution among our dataset, followed by a repeated-measures ANOVA with bonferroni corrections for longitudinal comparisons of BGLs.
20 patients (25% male) measured their BGLs using a glucometer for two weeks post CSI. The mean age was 60.5 +/- 13.3 years (range 35-78 years) with a mean BMI of 33.1 +/- 7.5 kg/m2 and a mean HbA1C value of 7.7 +/- 1.4%. Only 3 patients demonstrated a normal HbA1C level between 4-6%. Mean patient BGLs at baseline were 140.25 +/- 8.26 mg/dL. We found BGLs were 68.7% (236.62 +/- 14.6 mg/dL) and 91.0% (267.91 +/- 16.8 mg/dL) higher on day of injection and post injection day 1 when compared to baseline, respectively (p<0.05). We also found post injections day 2, 3, and 4. were also 72.6% (242.13 +/- 16.2 mg/dL), 38.9%(194.92 +/- 12.5 mg/dL), and 34.46%(188.59 +/- 8.85 mg/dL) higher when compared to baseline, respectively (p<0.05). Lastly, no other subsequent time points were significantly different from baseline (p>0.05).
The main finding of our pilot study suggests BGLs are significantly elevated during the injection day and first four post-injection days when compared to baseline, with the highest mean value occurring on the first post-injection day. Our results align with previous research of CSIs significantly increasing BGLs in diabetic patients with HbA1C levels greater than 7% in the first post-injection and injection day. We can extrapolate from our results that two weeks is enough time for BGLs to return to near baseline BGLs in our patient population. In conclusion, diabetic patients with elevated HbA1C should monitor their BGLs more closely after receiving a CSI.