Background: There is some evidence supporting associations between metabolic factors, clinical hand osteoarthritis (OA) and radiographic knee OA. However, more studies are needed regarding early knee OA.

Objectives: The aim was to study associations between metabolic factors and clinical hand OA at baseline in a cohort of individuals with knee pain, with and without radiographic knee OA.

Methods: In an ongoing five-year longitudinal study of knee pain, hand OA was assessed by clinical examinations in 296 of the included individuals at baseline [1]. BMI, waist circumference (WC) and blood pressure was measured. Body composition was assessed with Inbody 770. Fasting plasma glucose, triglycerides, cholesterol, HDL-and LDL-cholesterol and HbA1c was analysed. Metabolic syndrome (MetS)was present if central obesity (WC ≥94 cm in men and ≥80cm in women) plus any two of the following factors: raised blood pressure (systolic blood pressure ≥ 130 or diastolic blood pressure ≥ 85 mm Hg or treatment of hypertension), raised triglycerides (≥ 1.7 mmol/L or specific treatment), reduced HDL-cholesterol (men < 1.03 mmol/L and women < 1.29 mmol/L or specific treatment), raised glucose (glucose ≥ 5.6 mmol/L, or type 2 diabetes). Hand strength and self-reported disability of the arm, shoulder and hand (quickDASH) was assessed.

The individuals were divided according to having clinical hand OA or not, according to Altman [1]. The associations between background factors and clinical hand OA were calculated by crude logistic regression analyses, adjusting for age and sex.

Results: Fifty-five percent of the individuals in the study was overweight or obese, 40% had MetS and 23% had radiographic knee OA. In total 34% of the individuals had clinical hand OA. The group with hand OA were older, had higher proportion of body fat, fasting plasma glucose, HbA1C, worse quickDASH score and lower hand strength, table 1. Clinical hand OA was significantly associated to higher age (OR 1.04, 95%CI 1.01-1.07), higher fasting plasma glucose (1.56, 1.05-2.30), worse quickDASH (1.04, 1.02-1.06) and lower hand strength (0.99, 0.99 -0.998), but not to proportion of body fat and HbA1c.

Conclusion: In this cross-sectional study, the only metabolic factor associated with clinical hand OA was fasting plasma glucose. Contrary to other studies, there were no gender differences found. The association between development of clinical hand OA and metabolic factors in individuals with knee pain need to be further assessed in longitudinal studies.