Gabapentin in Complex Treatment of Neuropathic Pain in the Lower Back in Geriatric Patients

Relevance. Currently, the use of anticonvulsants is widely accepted in the treatment of neuropathic pain. Gabapentin, a drug within this group, is renowned for its effectiveness as it shares similarities with the neurotransmitter gamma-aminobutyric acid (GABA). In addition to enhancing GABA synthesis, gabapentin affects NMDA receptors, blocks the α2-δ subunit of calcium channels, inhibits glutamate synthesis and transport, reduces the release of monoamines, and substance P.

Aim. To study the effect of gabapentin in the complex treatment of chronic neuropathic low back pain syndrome in geriatric patients.

Materials and Methods. We conducted a study on the use of gabapentin in the comprehensive treatment of 28 geriatric patients aged 65 to 98 years, who had glomerular filtration rate (GFR) values of at least 30 mL/min according to the Cockcroft-Gault formula, and chronic neuropathic pain syndromes in the lower back, constituting the main group (MG). The control group (CG) consisted of 20 patients aged 65 to 97 years with a similar clinical presentation. The inclusion criterion was the presence of sleep disorders in patients associated with the presence of lower back pain, as assessed by the «Subjective Sleep Characteristics Assessment Questionnaire» — SSCAQ.

Results. The average pain score in the MG and CG was 8.7 ± 1.3 and 8.1 ± 1.6 on the Visual Analogue Scale (VAS), respectively. The average sleep disturbance score in the MG and CG was 13.6 ± 2.1 and 12.4 ± 3.3 on the SSCAQ, respectively. All patients in both groups received standard treatment, including local, intravenous, intramuscular, and oral administration of analgesics, anesthetics, muscle relaxants, nonsteroidal anti-inflammatory drugs (NSAIDs), and physiotherapy procedures. In addition, patients in the MG received gabapentin, starting from the first day of treatment, with a daily dose of 300–900 mg, taking into account the signs of decreased GFR. The average dose of the medication in 80% of cases was 600 mg per day, administered as 300 mg twice daily. Two patients in the main group were excluded from the study due to the side effect of foot edema at a dose of 600 mg per day.

The intensity of the pain syndrome significantly decreased after treatment in both groups, averaging 2.7 ± 0.8 in the MG and 4.2 ± 1.1 in the CG, i.e. decreased by 78.07% and 50%, respectively (p < 0.01). Sleep disorders were on average 23.4 ± 4.8 in the MG, and 16.9 ± 4.3 in the CG, i.e. decreased by 41.9% and 26.6% (p < 0.01). The duration of inpatient treatment was 16.8 ± 2.4 days in the group and 19.1 ± 3.7 days in the control group. The drug was continued on an outpatient basis in selected dosages.

Conclusion. The research has shown that a daily intake of 600 mg of gabapentin, divided into two 300 mg doses, is the recommended dose for treating chronic neuropathic pain syndrome and sleep disorders in elderly patients aged 65 to 98. Factors to consider when administering gabapentin to older patients include adjusting the drug dose according to routinely monitored renal GFR, using the drug in a lower dose resulting in improved treatment outcomes thus increasing overall effectiveness from treatment, providing faster relief from neuropathic pain in the lower back, prolonged sleep, limiting the duration of inpatient treatment, maintaining adherence to various outpatient care over a long period.