AGE- AND SEX-RELATED DIFFERENCES IN RESPONSE TO ANALGESIC TREATMENTS IN CHRONIC PAIN PATIENTS: A REAL-WORLD OBSERVATIONAL STUDY

S. Stimolo¹, S. Zappalà¹, M. Maria², S. Brundo², R. Chiaramonte², E. Buccheri², S. Caramma² | ¹Università di Padova, Italy; ²Policlinico di Catania, Italy

Introduction. Chronic pain is a leading cause of disability, driven by biological, psychological, and sociocultural factors [1, 2]. Evidence highlights significant sex-related differences in pain perception and clinical outcomes following analgesic therapies [1, 3]. This study evaluates the association between biological sex, age, and treatment response in a real-world cohort with moderate-to-severe chronic pain.
Methods. An observational study was conducted at the Pain Management Unit (UOSD Terapia del Dolore) of the Policlinico-San Marco Hospital in Catania. We enrolled 100 patients with chronic pain lasting ≥3 months and moderate-to-severe baseline intensity (NRS > 5). Participants were equally distributed between women (n=50, mean age: 50.4±12.1 years) and men (n=50, mean age: 54.3±13.0 years). Diagnoses included chronic low back pain (n=40; 22 men, 18 women), peripheral neuropathies (n=35; 18 men, 17 women), and fibromyalgia (n=25; 10 men, 15 women). Among patients on stable opioid therapy (n=32), the mean daily dosage was 60 mg morphine equivalents [4]. For subgroup analyses, cohorts were stratified using an age cut-off of 54 years, corresponding to the mean age of the post-menopausal female subgroup (n=28) [3]. Outcomes, assessed at baseline, 1 month, and 3 months, included NRS scores and the Patient Global Impression of Change (PGIC) scale.
Results. At baseline, women reported higher mean NRS scores than men in low back pain (7.8±1.1 vs 7.2±1.0), fibromyalgia (8.1±0.8 vs 7.5±0.9), and peripheral neuropathies (7.4±1.0 vs 7.2±1.2) [1, 3]. After 3 months, men with low back pain showed a significantly greater NRS reduction compared to women (ΔNRS -3.3 vs -2.6; p=0.03). Conversely, in fibromyalgia, clinical improvement was more pronounced in females (ΔNRS -3.2; p<0.01) than in males (ΔNRS -2.2; p=0.07). Achieving a meaningful pain reduction (ΔNRS ≥ 30%) was less frequent in patients aged >54 years compared to younger cohorts (41.4% vs 66.0%; p=0.04) [2]. Among patients on opioids, a PGIC ≥ 5 was observed more frequently in peripheral neuropathies and low back pain than in fibromyalgia, which exhibited the lowest response rates regardless of sex, except for pre-menopausal women treated with tapentadol (50.0%).
Conclusions. Biological sex and chronological age significantly modulate baseline pain intensity and therapeutic responsiveness. Older individuals and patients with nociplastic profiles are less likely to achieve significant pain relief [2]. These data reinforce the need for personalized, gender-specific therapeutic strategies and multidimensional pain management, balancing adverse events with appropriate clinical interventions [1, 4].