Association Between Diabetes Mellitus and Carpal Tunnel Syndrome: Results From the United States National Ambulatory Medical Care Survey

Characteristics of diabetic and non-diabetic carpal tunnel syndrome in terms of clinical, electrophysiological, and Sonographic features: a cross-sectional study

BACKGROUND

Although diabetes is considered a major risk factor for carpal tunnel syndrome (CTS), the characteristics of diabetic CTS have not been fully understood.

OBJECTIVE

This study is aimed at evaluation of the clinical, electrophysiological, and ultrasonographic findings of non-diabetic and diabetic CTS.

METHODS

This retrospective, cross-sectional study included patients diagnosed with CTS. Patient age, sex, involved side, body mass index, clinical and electrophysiological findings, and median nerve cross-sectional area (CSA) were identified. Diabetes was identified through patient or guardian interviews, medical records, and medication history. Linear and binary logistic regression models were established to confirm the associations between the electrophysiological findings, median nerve CSA, and clinical outcomes. Covariates, such as age, sex, body mass index, diabetes, symptom duration, and thenar muscle weakness were adjusted.

RESULTS

Out of the 920 hands, 126 and 794 belonged to the diabetic and non-diabetic CTS groups, respectively. The patients were significantly older in the diabetic CTS group (P < 0.001). The rate of thenar weakness in the diabetic CTS group was also significantly higher than that in the non-diabetic CTS group (P = 0.009). The diabetic CTS group had a more severe electrodiagnostic grade (P = 0.001). The prolonged onset latency of the compound motor nerve action potential (CMAP) and median nerve CSA were well associated with the degree of clinical symptoms. Increased median nerve CSA was significantly associated with prolonged CMAP onset latency (β = 0.64; P = 0.012), prolonged transcarpal latency (β = 0.95; P = 0.044), and decreased CMAP amplitude (β = -0.17; P = 0.002) in the non-diabetic CTS group.

CONCLUSION

Diabetic CTS had more profound electrophysiological abnormalities. Distal motor latency and median nerve CSA were not only associated with each other, but also with clinical symptoms. Further studies are needed to investigate the pathophysiological mechanisms underlying diabetic CTS.

Risk factors for carpal tunnel syndrome in patients attending the primary care center of a tertiary hospital in Riyadh, Saudi Arabia: A case-control study

BACKGROUND

Carpal tunnel syndrome (CTS), the most common entrapment neuropathy in the upper extremity, is known to be a multi-factorial disease that raises medical and nonmedical risk factors. The aim of the current study was to determine the risk factors of CTS in patients attending the primary care center at a tertiary hospital.

MATERIALS AND METHODS

A case-control study was conducted by reviewing all medical records of patients above the age of 18 years old diagnosed with CTS from 2015 to 2021. The selected cases were evaluated by physical examination and confirmed by a nerve conduction study. Cases and controls were matched by age, gender, and nationality, with a case-to-control ratio of 1:2. Odds ratios were calculated for association between carpel tunnel syndrome and various factors and Chi-sqauare test determined statistical significance. Multiple logistic regression was performed to adjust for confounding.

RESULTS

The study recruited 144 cases with a mean age of 53.38 ± 12.20 years and 288 controls with a mean age of 53.80 ± 12.27 years. The majority of subjects were female (84.7%) and of Saudi nationality (68.3%). There was a significant difference in body mass index, employment status, number of years of employment, occupation, mean systolic blood pressure, mean low-density lipoprotein cholesterol level, and mean blood urea level between cases and controls (P < 0.05). Laboratory tests that were found to be significantly associated with CTS in univariate analysis were thyroid-stimulating hormone (crude odds ratio [COR] = 0.828) and urea level (COR = 0.802). In fully adjusted analyses, obesity (adjusted odds ratio [AOR] =3.080), chronic kidney disease (AOR = 3.629), and the use of corticosteroid (AOR = 0.470) were also significantly associated with CTS.

CONCLUSION

Similar to the findings of other studies, this study identified several potential risk factors for CTS. More large-scale longitudinal studies are required to establish a precise causal association.

Is Smoking Associated with Carpal Tunnel Syndrome? A Meta-Analysis

To date, the role of smoking in carpal tunnel syndrome (CTS) is unclear. The aim of this systematic review and meta-analysis was to assess the association between smoking and CTS. The literature searches were conducted in PubMed, Embase, and Scopus, from inception until October 2021. Three reviewers screened the titles, abstracts, and full-text articles and evaluated the methodological quality of the included studies. A random-effects meta-analysis was used, and heterogeneity across studies was examined using I² statistic. A total of 31 (13 cross-sectional, 10 case-control, and 8 cohort) studies were qualified for meta-analysis. In a meta-analysis of cohort studies, the risk of CTS did not differ between current and never smokers (pooled hazard ratio (HR) 1.09, 95% CI 0.84–1.43), current and past/never smokers (HR 1.07, 95% CI 0.94–1.23), and past and never smokers (HR 1.12, 95% CI 0.83–1.49). Furthermore, a meta-analysis of case control studies found no difference in the risk of CTS between current and never smokers (pooled odds ratio (OR) 0.92, 95% CI 0.56–1.53), current and past/never smokers (OR 1.10, 95% CI 0.51–2.36), and past and never smokers (OR 0.91, 95% CI 0.59–1.39). However, a meta-analysis of cross-sectional studies showed the associations of ever (OR 1.36, 95% CI 1.08–1.72) and current smoking (OR 1.52, 95% CI 1.11–2.09) with CTS. However, the association between ever smoking and CTS disappeared after limiting the meta-analysis to higher quality studies or after adjusting for publication bias. The association between current smoking and CTS also attenuated after limiting the meta-analysis to studies that confirmed CTS by a nerve conduction study or studies with low attrition bias. This meta-analysis does not support an association between smoking and CTS. The association between smoking and CTS observed in cross-sectional studies could be due to biases and/or confounding factors.

Prevalence and predictive factors for bilateral carpal tunnel syndrome by electrodiagnosis: A retrospective study

Introduction

Carpal tunnel syndrome (CTS) is the most common compressive neuropathy. Patients who have unilateral symptoms are frequently found to have bilateral CTS by electrodiagnostic (EDx) study. We aimed to (a) study the prevalence and identify the predictive factors for bilateral CTS diagnosed by EDx; and (b) develop a model to predict bilateral CTS.

Methods

The retrospective clinical and EDx data of patients with CTS were collected and analyzed using the Chi-squared test and multiple logistic regression analysis. A model was fitted, and the best cutoff point determined. Calibration and discrimination performance of the model were performed.

Results

A total of 327 patients with a mean age of 50.0 years were enrolled. Most were women (82.6%), and the most common presenting symptom was hand numbness (93.6%). The median duration of symptoms was 60 days. The prevalence of bilateral CTS was 80.7%. In the multivariate analysis, the predictive factors for bilateral CTS were the presence of bilateral symptoms (AOR 6.7 [95%CI 3.1–14.3]), thenar muscle weakness (AOR 3.9 [95%CI 1.3–11.6]), and age ≥ 45 years (AOR 2.5 [95%CI 1.3–4.6]). The logistic regression model was fitted, and the best cutoff point determined. The area under the receiver operating curve (AUC) was 0.76. The respective optimism-corrected C index and Somers’ D was 0.762 and 0.524.

Conclusion

The prevalence of bilateral CTS was 80.7%. Our findings suggest bilateral CTS was predicted with adequate diagnostic accuracy by bilateral symptoms, age ≥ 45 years, and thenar muscle weakness.

Effects of diabetes mellitus on the rate of carpal tunnel release in patients with carpal tunnel syndrome

The objective of this study was to evaluate the effects of diabetes mellitus (DM) on the rate of carpal tunnel release (CTR) using a large nationwide cohort in Korea and to identify risk factors, including comorbidities and socioeconomic status (SES), associated with CTR. Patients with a primary or secondary diagnosis of carpal tunnel syndrome (CTS; ICD-10 code: G560) were selected and divided into two groups according to the presence of DM. A Cox proportional hazard model was used to assess the rate of CTR between the two groups. To evaluate the influence of demographic factors, comorbidities, and SES on CTR, multivariate Cox proportional hazard regression models were used to adjust for confounding variables. In total, 12,419 patients with CTS were included in the study: 2487 in DM cohort and 9932 in non-DM cohort. DM duration was negatively related with the rate of CTR (HR = 0.89, 95% CI 0.87–0.91) in CTS patients with DM. The rate of CTR was decreased in patients with DM compared to those without DM in the unadjusted model; however, after adjusting for comorbidities, DM had no significant effect on the rate of CTR. Female sex (HR = 1.50, 95% CI 1.36–1.67) correlated with the rate of CTR, and an inverse relationship between the number of comorbidities and CTR was found (p < 0.001) irrespective of DM. Diabetic polyneuropathy (DPN) was not associated with CTR, and we did not find any factors correlating with CTR in DPN patients. We found that CTS patients with more comorbidities or combined with a longer duration of DM were undertreated in real-word practice. Actual outcomes of CTR in CTS patents with various comorbidities should be investigated in future studies for optimal management of CTS.