Clinical trial NCT07013305: Pre- and Post-Treatment Investigation of B12 and Folic Acid (Folate) Levels in Patients Receiving Antiepileptic (Anticonvulsant) Treatment for Fibromyalgia: Retrospective Study
Official title: Pre- and Post-Treatment Investigation of B12 and Folic Acid (Folate) Levels in Patients Receiving Antiepileptic (Anticonvulsant) Treatment for Fibromyalgia: Retrospective Study
Study type: OBSERVATIONAL
Overall status: NOT_YET_RECRUITING
Conditions: Fibromyalgia (FM)
Vitamin B 12 Deficiency
Folic Acid Deficiency
Keywords: Antiepileptic (anticonvulsant) drugs
Vitamin D deficiency
Lead sponsor: Gaziosmanpasa Research and Education Hospital
Sponsor class: OTHER_GOV
First posted: 2025-06-10
Enrollment: 80
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CROSSOVER
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients who were followed up for 6 months in the physical medicine and rehabilitation clinic with a diagnosis of fibromyalgia and who used antiepileptic (anticonvulsant) drugs will be retrospectively evaluated for the 6 months period (June-December 2024) before the ethics committee approval was obtained. Blood vitamin B12 and folate (folic acid) levels of the patients before and after antiepileptic drug use will be determined. Patients will be evaluated whether there is a change in vitamin B12 and folic acid levels depending on drug use.

Brief summary: Fibromyalgia is a rheumatological disorder characterised by chronic widespread body pain, second most common after osteoarthritis. The overall prevalence is 2-8% and it is more common in women. Diffuse body pain, fatigue, sleep and cognitive dysfunction occur. The etiology of fibromyalgia is multifactorial and occurs due to central and peripheral pain mechanisms that occur with neuroendocrine imbalance due to psychological and physical stress in people with genetic predisposition. The diagnostic criteria for fibromyalgia were updated by the American College of Rheumatology in 2016 to include a widespread body pain scale and a symptom severity scale.

Fibromyalgia treatment consists of drug (antidepressants and antiepileptics) and non-drug treatments. Pregabalin is also used in the treatment of epilepsy by blocking and modulating the α2 δ subunit of voltage-dependent calcium channels. There are studies showing that antiepileptics cause folate and vitamin B12 deficiency in epilepsy patients. In our study, we aimed to retrospectively investigate vitamin B12 and folic acid levels before and after treatment in patients with fibromyalgia using antiepileptics (anticonvulsants).

Detailed description: After the acceptance of the study (after obtaining ethics committee approval), patients who have been followed up for at least 6 months in the physical medicine and rehabilitation outpatient clinic with a diagnosis of fibromyalgia and who use pregabalin will be evaluated retrospectively (1-year records). Blood vitamin B12 and folate (folic acid) levels of the patients before and after antiepileptics (anticonvulsants). use will be determined. Patients will be evaluated whether there is a change in vitamin B12 and folic acid levels due to antiepileptics (anticonvulsants) drug use.

Eligibility criteria: Inclusion Criteria:

* Patients aged 18-75 years who have been diagnosed with fibromyalgia, whose vitamin B12 and folic acid levels have been analysed, who do not receive vitamin B12 and folic acid treatment, and who do not have diabetes mellitus, liver and kidney failure

Exclusion Criteria:

* Patients receiving vitamin B12 and folic acid therapy at the time of antiepileptic (anticonvulsant) drugs initiation, patients with hepatic and renal insufficiency

Primary outcomes:
measure: Vitamin B12 level analysed before treatment (pre-treatment) (retrospective)
timeFrame: Within 1 month
measure: Vitamin B12 level analysed after treatment (post-treatment) (retrospective)
timeFrame: Within 1 month
measure: Folic acid level analysed before treatment (pre-treatment) (retrospective)
timeFrame: Within 1 month
measure: Folic acid level analysed after treatment (post-treatment) (retrospective)
timeFrame: Within 1 month
Secondary outcomes:
measure: 25-OH Vitamin D level analysed before treatment (pre-treatment) (retrospective)
timeFrame: Within 1 month
measure: 25-OH Vitamin D level analysed after treatment (post-treatment) (retrospective)
timeFrame: Within 1 month
Other outcomes:
Locations:
city: Istanbul
country: Turkey
facility: Gaziosmanpasa Research and Education Hospital
state: Gaziosmanpasa
Study officials:
References:
citation: Mula M, Sander JW. Negative effects of antiepileptic drugs on mood in patients with epilepsy. Drug Saf. 2007;30(7):555-67. doi: 10.2165/00002018-200730070-00001.
citation: Clauw DJ. Fibromyalgia: a clinical review. JAMA. 2014 Apr 16;311(15):1547-55. doi: 10.1001/jama.2014.3266.
citation: Talotta R, Bazzichi L, Di Franco M, Casale R, Batticciotto A, Gerardi MC, Sarzi-Puttini P. One year in review 2017: fibromyalgia. Clin Exp Rheumatol. 2017 May-Jun;35 Suppl 105(3):6-12. Epub 2017 Jun 28.
citation: Aslan K, Bozdemir H, Unsal C, Guvenc B. The effect of antiepileptic drugs on vitamin B12 metabolism. Int J Lab Hematol. 2008 Feb;30(1):26-35. doi: 10.1111/j.1751-553X.2007.00910.x.
citation: Linnebank M, Moskau S, Semmler A, Widman G, Stoffel-Wagner B, Weller M, Elger CE. Antiepileptic drugs interact with folate and vitamin B12 serum levels. Ann Neurol. 2011 Feb;69(2):352-9. doi: 10.1002/ana.22229. Epub 2011 Jan 19.