Identification of Responders to Balneotherapy among Adults over 60 Years of Age with Chronic Low Back Pain: A Pilot Study with Trajectory Model Analysis.

Balneotherapy may be a relevant treatment for chronic low back pain (LBP) in individuals > 60 years old. This pilot study aimed to determine the effectiveness of balneotherapy for chronic LBP in people > 60 years old and to determine profiles of responders with trajectory model analysis. This was a pilot prospective open cohort study, with repeated measurements using validated questionnaires; participants were their own controls. The primary endpoint was the proportion of participants with a change in pain intensity between the start of treatment and 3 months after treatment assessed with a numeric scale (NS) from 0 to 100 mm, with an effect size (ES) > 0.5. The assessments involved questionnaires that were self-administered on days (D) 1 and 21 and at months 3 and 6. The secondary objective was to determine the profile of responders to balneotherapy. We included 78 patients (69.2% women), mean age 68.3 ± 5.3 years. The mean pain score on the NS was 48.8 ± 19.9 at D1 and 39.1 ± 20.5 at 3 months (p < 0.001). The ES was 0.47 [95% confidence interval [CI] 0.25 to 0.69] for the whole sample; 36% (28/78) had an ES > 0.5; 23% (18/78) had a moderate ES (0 to 0.5); and 41% (32/78) had an ES of zero (14/78) or < 0 (18/78), corresponding to increased pain intensity. The pain trajectory model showed that the change in pain between D1 and D21 for trajectory A (larger reduction in pain intensity) was -50% [95% CI -60 to -27], and for trajectory B (smaller reduction in pain intensity), it was -13% [-33 to 0] (p < 0.001). Between Day 1 and month 3, the change for trajectory A was -33% [-54; 0] and for trajectory B was -13% [-40 to 0] (p = 0.14). Finally, between D1 and month 6, the change for trajectory A was -50% [-60 to 0] and for trajectory B was -6% [-33 to 17] (p = 0.007). The patients in trajectory A reported performing more physical activity than those in trajectory B (p = 0.04). They were also less disabled, with a mean Oswestry Disability Index of 40.4 versus 45.7 for those in trajectory A and B, respectively, (p = 0.03) and had a higher total Arthritis Self-Efficacy Scale score. This real-life study of the effectiveness of balneotherapy on chronic LBP identified distinct pain trajectories and predictive variables for responders. These criteria could be used in decision-making regarding the prescription of balneotherapy, to ensure personalized management of chronic LBP.

Level of obesity is directly associated with the clinical and functional consequences of knee osteoarthritis.

Obesity is one of the most important risk factors of knee osteoarthritis (KOA), but its impact on clinical and functional consequences is less clear. The main objective of this cross-sectional study was to describe the relation between body mass index (BMI) and clinical expression of KOA. Participants with BMI ≥ 25 kg/m2 and KOA completed anonymous self-administered questionnaires. They were classified according to BMI in three groups: overweight (BMI 25-30 kg/m2), stage I obesity (BMI 30-35 kg/m2) and stage II/III obesity (BMI ≥ 35 kg/m2). The groups were compared in terms of pain, physical disability, level of physical activity (PA) and fears and beliefs concerning KOA. Among the 391 individuals included, 57.0% were overweight, 28.4% had stage I obesity and 14.6% had stage II/III obesity. Mean pain score on a 10-point visual analog scale was 4.3 (SD 2.4), 5.0 (SD 2.6) and 5.2 (SD 2.3) with overweight, stage I and stage II/III obesity, respectively (p = 0.0367). The mean WOMAC function score (out of 100) was 36.2 (SD 20.1), 39.5 (SD 21.4) and 45.6 (SD 18.4), respectively (p = 0.0409). The Knee Osteoarthritis Fears and Beliefs Questionnaire total score (KOFBEQ), daily activity score and physician score significantly differed among BMI groups (p = 0.0204, p = 0.0389 and p = 0.0413, respectively), and the PA level significantly differed (p = 0.0219). We found a dose-response relation between BMI and the clinical consequences of KOA. Strategies to treat KOA should differ by obesity severity. High PA level was associated with low BMI and contributes to preventing the clinical consequences of KOA.