Previous studies have indicated more severe symptoms of osteoarthritis (OA) and higher rates of arthroplasty in patients with type 2 diabetes (T2D).1 In addition, it has been suggested that long-term insulin use may overload some tissues with enriched insulin receptor, which may affect pain perception.2 A hospital-based cohort study published in BMJ Open Diabetes Research & Care found sex heterogeneity in the relationship between T2D and severity of OA symptoms and an association between insulin treatment and pain severity in men.3
A total of 700 patients with OA and total arthroplasty, or those waiting for the surgery, volunteered to take part in the study. Eligible patients experienced pain at the hip and/or knee joints. Comparisons for pain severity were made between patients with T2D, who were clinically diagnosed with T2D or were self-diagnosed with a fasting blood glucose of ≥126 mg/dL, and patients without diabetes. Patients with other conditions, such as rheumatoid arthritis, lupus, avascular necrosis, and fractures, were excluded.
In total, 489 patients contributed to the study. The mean age of participants was 65.8±10.6 years and 61.6% were women. Most of the participants had obesity, with an average body mass index of 31.6±6.1 kg/m2 for women and 29±5.6 kg/m2 for men (P <.001). A total of 28.4% of participants were diagnosed with T2D (30% of men vs 28% of women; P =.03). Female participants reported more OA pain than men.
Participants used a numerical rating scale from 0 to 10 to report the pain severity in each affected joint. Pain severity scores were calculated by adding the number of painful joints with the highest pain rating reported for any joint. Men with T2D had a slightly higher pain severity score than their counterparts without diabetes (P =.01), including in non-weight-bearing joints. In men, the most severe pain score was found in those receiving insulin treatment compared with all other patients (P =.025). Similar associations were not found in women. The most significant indication for pain severity in women was waist circumference, irrespective of body mass index (P =.002).
Furthermore, men with T2D consumed 3 times more analgesics than men without T2D (84% vs 61%; odds ratio, 3.03; 95% CI, 1.24-7.36; adjusted P =.01). There was no difference in analgesic consumption in women with vs without diabetes (P =.66).
This study found that men with T2D and OA, and especially men receiving insulin treatment, report higher pain severity, have more joints affected by pain, and consume more analgesics than men without diabetes. The presence of pain in non-weight-bearing joints, such as the hands, might suggest that diabetic neuropathy affects the severity of OA. As sensorimotor neuropathy presents earlier and has a higher prevalence in men with diabetes than in women, this may explain the sex difference in reported pain severity. The association of pain severity with waist circumference in women fits a previously proposed theory that there is a link between metabolic syndrome and chronic pain.4 The role of diabetic medication in OA pain had not been explored before this study, noted the researchers, and the effect of insulin administration on OA progression requires further investigation.
1. Schett G, Kleyer A, Perricone C, et al. Diabetes is an independent predictor for severe osteoarthritis: results from a longitudinal cohort study. Diabetes Care. 2013;36;403-409.
2. Rosa SC, Ruffino AT, Judas F, et al. Expression and function of the insulin receptor in normal and osteoarthritic human chondrocytes: modulation for anabolic gene expression, glucose transport and GLUT-1 content by insulin. Osteoarthritis Cartilage. 2011;19:719-727.
3. Castano Betancourt MC, Morais CL, Vannucci Nunes Lipay M, et al. Gender differences in the effect of diabetes mellitus and its treatment on osteoarthritic pain. BMJ Open Diab Res Care. 2019;7:e000736.
4. Loevinger BL, Muller D, Alonso C, Coe CL. Metabolic syndrome in women with chronic pain. Metabolism. 2007;56(1):87-93.