Effects of Curcumin-Piperine Supplementation in Fibromyalgia

Assessment of pain severity measured by the Visual Analog Scale (VAS)

VAS is a self-administered instrument widely used in fibromyalgia research and clinical practice to assess pain intensity and monitor treatment response. The VAS uses a 10-cm horizontal line anchored by 0 (no pain) and 10 (worst imaginable pain). It will be measured at baseline, after 1 month, and after 3 months.

The Revised Fibromyalgia Impact Questionnaire (FIQR)

is a disease-specific, patient-reported outcome measure designed to assess disease severity and the overall impact of fibromyalgia. It comprises 21 items grouped into three domains: function (9 items assessing physical activities), overall impact (2 items evaluating the extent to which fibromyalgia interferes with goal achievement and causes a feeling of being overwhelmed), and symptoms (10 items assessing pain, fatigue, sleep quality, stiffness, depression, anxiety, memory, balance, tenderness, and environmental sensitivity). All items are rated on a 0-10 numeric scale. The total FIQR score ranges from 0 to 100, with higher scores indicating greater disease impact and symptom severity. It will be measured at baseline, after 1 month, and after 3 months

The Hospital Anxiety and Depression Scale (HADS)

The scale consists of 14 self-reported items, divided equally into two domains: anxiety (HADS-A) and depression (HADS-D). Each item is rated on a 4-point Likert scale (0-3), yielding subscale scores ranging from 0 to 21, where higher scores indicate greater symptom severity. A cut-off score of ≥8 on either subscale is considered indicative of clinically relevant anxiety or depression. Elevated HADS scores in this population have been consistently associated with higher symptom severity, increased pain intensity, poorer sleep quality, reduced quality of life, and functional impairment. It will be measured at baseline, after 1 month, and after 3 months.

The 36-Item Short Form Health Survey (SF-36)

SF-36 is a validated, self-administered, generic instrument used to assess health-related quality of life in fibromyalgia research by evaluating both physical and mental health status. It consists of 36 items covering eight domains: physical functioning, role limitations due to physical health, bodily pain, general health perceptions, vitality, social functioning, role limitations due to emotional problems, and mental health. Domain scores are transformed to a scale ranging from 0 to 100, where 0 represents the worst and 100 the best perceived health status, and are aggregated into two summary measures: the Physical Component Summary (PCS) and the Mental Component Summary (MCS). It will be measured at baseline, after 1 month, and after 3 months

Serum inflammatory biomarkers: IL-6

Collected serum samples will be stored at -80 C until analysis. Serum IL-6 will be assessed using enzyme-linked immunosorbent assay (ELISA) kits. It will be measured at the start and end of the study (after 3 months).