Pos1339 efficacy of very low-calorie ketogenic diet in obese patients with fibromyalgia: preliminary results from a monocentric interventional study

Background Obesity can worsen fibromyalgia (FM) and very low-calorie ketogenic diet (VLCKD) is a potential therapeutic option in diseases that share clinical and pathophysiological features with FM [1]. Objectives In this pilot interventional study, we investigate the effects of VLCKD in obese patients with FM. Methods Adult FM patients with a BMI ≥ 30 kg/m [2] and who had failed standard low-calorie diets, were eligible for VLCKD. The weight-loss program was preceded by 4 weeks of free-diet (W-4 to W0). During the first period of VLCKD (W1 to W4), patients could eat protein preparations and vegetables. In the next phase (W5 to W8), natural proteins were gradually integrated in the dietary regimen. Ketosis was assessed weekly with urine strips. Carbohydrates were then progressively reintroduced (W9 to W20). Changes in BMI, FM impact questionnaire (FIQ) and Hospital Anxiety and Depression Scale (HADS-A for anxiety and HADS-D for depression) were evaluated at established timepoints. As previously reported, a change of 14% in FIQ was considered clinically relevant [2]. This interim analysis evaluates patients who reached the final visit after 20 weeks from the beginning of VLCKD (W20). Results At data cut-off, 20 patients, all females, were enrolled in the study. Two patients discontinued the intervention while 4 are currently in the maintenance phase. Mean age of the 14 patients who reached W20 was 50.4 years and BMI was 36.9. Baseline characteristics are summarized in Table 1. No significant difference in BMI, FIQ, HADS-A and HADS-D was observed from W-4 to W0. All patients lost weight during the first period of VLCKD and this achievement was maintained through W20 (Figure 1, panel A). Mean BMI decreased from 36.9 at W0 to 34.5 at W4, 33.3 at W8 and 32.2 at W20 (all p <0.001 compared to W0). Compared to W0, a significant reduction of mean FIQ (Figure 1, panel B) from 64.3 to 35.2 was observed at the end of W4 (p <0.001) and was maintained also at W8 (mean FIQ of 38.8; p =0.004) and at W20 (mean FIQ of 39.1; p =0.007). Analysing the trend in each participant, at W4, all 14 patients showed a reduction in FIQ, which was clinically relevant in 13 (93%). Compared to W0, a meaningful improvement in FIQ was still observed at W20 in 12 cases (86%). However, change in BMI was not significantly correlated with change in FIQ at any timepoint. HADS-A and HADS-D improved significantly from W0 to W4, W8 and W20. (Figure 1, panels C, D). Mild constipation was reported by 8 patients (57%), fatigue by 4 (29%) and headache by 3 (21%). No major safety concern emerged. Conclusion These are the first data on the efficacy of VLCKD in FM. All patients achieved improvement in disease activity outcomes during the ketogenic phase, which was maintained also after carbohydrate reintroduction. Our data suggest that ketosis might exert beneficial effects in FM which extend beyond the promotion of rapid weight loss. References [1]Vidali S et al. Mitochondria: The ketogenic diet--A metabolism-based therapy. Int J Biochem Cell Biol 2015;63:55-9. [2]Bennett RM et al. Minimal clinically important difference in the fibromyalgia impact questionnaire. J Rheumatol 2009;36(6):1304-11. Table 1. Characteristics of patients included in the study Characteristics Patients n=14 Age, mean (SD ) 50.4 (9.6) Body mass index, mean (SD ) 36.9 (3.7) Disease duration, years, median (IQR ) 4.0 (1.6 - 6.4) Comorbidities Diabetes, n (% ) 0 Hyperlipidemia, n (% ) 10 (71) Hypertension, n (% ) 7 (50) Fatty liver disease, n (% ) 5 (36) Congestive heart failure, n (% ) 0 Atherosclerosis, n (% ) 0 Polycystic ovary syndrome, n (% ) 2 (14) Therapy Non-steroidal anti-inflammatory drugs, n (% ) 6 (43) Opioids, n (% ) 1 (7) Paracetamol, n (% ) 6 (43) Corticosteroids, n (% ) 0 Muscle relaxants, n (% ) 1 (7) Antidepressants, n (% ) 3 (21) Gabapentinoids, n (% ) 2 (14) Benzodiazepines, n (% ) 2 (14) Figure 1. Changes in BMI, FIQ, HADS-A and HADS-D during the study period. Solid lines represent mean values, dashed lines represent standard deviations. Acknowledgements: NIL. Disclosure of Interests None Declared.