Patient characteristics in knee, hip and back pain patients participating in patient education and exercise therapy. a comparison of 46,273 patients from the glad registries in Denmark

Purpose: To report and compare baseline characteristics for patients attending structured patient education and exercise programs targeting knee and hip OA (GLA:D®) and back pain (GLA:D® Back) delivered in primary care in Denmark.

Methods: The two GLA:D® programs consist of 2-3 patient education sessions and 12 (knee/hip) and 16 (back) supervised exercise sessions delivered by certified health care practitioners, most commonly physiotherapists. The content is similar for patients with knee and hip OA but different for back pain patients. The program was introduced in Denmark in 2013 for knee and hip OA and in 2018 for back pain. Data were retrieved from the national electronic GLA:D® databases on August 1, 2019. Patients were categorized and compared according to their primary complaint being the knee, hip or back. Baseline characteristics are given as proportions or means and 95 % CIs.

Results: Detailed results are presented in Table 1. About 70% of participants in the two programs were female, with lower mean age for back pain (58) than for knee (65) and hip (66) OA patients. Knee OA patients had a higher BMI (28.9) than back (27.5) and hip (27.1) patients. Educational levels were similar across the different patient groups with about half of the patients having low educational level. Hypertension was a common medical co-morbidity (range 28-38 %), back pain was a frequent musculoskeletal co-morbidity among knee and hip OA patients (67 and 75 % respectively) and OA was frequent among back patients (46 %). Approximately 1 in 3 patients reported low levels of physical activity across groups and between 11 and 15 % have the impression that their hip/knee joints or back would be damaged from physical activity with the lowest proportion among hip patients. Across all patient groups at least half reported having symptoms for more than 1 year. More back pain patients had shorter than 3 months (19% vs. 5-7%) or longer than 1 year (60% vs. 52%) symptoms duration compared to knee and hip OA patients. Mean pain intensity was similar across groups with slightly higher intensity reported by back patients compared to hip and knee patients (5.4 vs. 4.8 and 4.8 on NRS (0-10)). Up to two-thirds reported to use analgesics, with the highest proportion in hip patients. The ability to rise from a chair was similar in all three groups, with the average patient completing 12 chair stands in 30 seconds. Mean general health (EQ-VAS 0-100, worst to best) varied between 62 and 69, with lowest mean score among back patients.

Conclusions: Characteristics of patients with pain primarily from knee OA, hip OA and the back participating in patient education and exercise therapy programs delivered in primary care are more alike than different and most statistically significant differences are not likely to be clinically relevant. At least two out of three OA patients reported co-morbid back pain and about every other back patient reported co-morbid OA.