Pregabalin

To assess whether the use of pregabalin in combined therapy provides better health outcomes in patients with cancer-related neuropathic pain

This study was a post hoc analysis of data from a previous epidemiologic study of clinical prevalence and analgesic management of neuropathic pain. Patients who received pregabalin versus those who did not were compared. Analgesic management was done at the individual physician’s discretion. Patients had a baseline visit and a final visit at eight weeks. In the initial study, patients were not randomized to different treatment, and numerous other interventions for analgesia were done.

• The study reported on a sample of 273 patients.
• Mean patient age was 62 years.
• The sample was 55.6% male and 44.4% female.
• Breast, lung, and genitourinary cancers were most prevalent.
• All patients were receiving radiation therapy.

• Multisite
• Outpatient setting
• Spain

Patients were undergoing active antitumor treatment.

The study was a post hoc analysis of data from a previous epidemiologic study.

• Brief Pain Inventory
• Hospital Anxiety and Depression Scale
• Medical Outcomes Sleep Scale
• Short-Form Health Survey (SF-12)

The most frequent cause of neuropathic pain was the tumor itself, and cisplatin was the most frequently used chemotherapeutic agent. Fentanyl patches were used more frequently in the pregabalin group. Pain intensity improved in all patients at eight weeks, but improved more with pregabalin (change = 0, 9 points, p = 0.0084). Depression and anxiety decreased significantly in both groups. Physical component and mental component scores on the SF-12 improved in all patients, but improved more in those on pregabalin. When data were adjusted for age and sex, differences from baseline scores were less than 1. There were significant differences in groups in other medications used, numbers of analgesic interventions, and amount of radiation therapy treatment.

It is difficult to draw any firm conclusions regarding efficacy of pregabalin from this study due to the differences in multiple other variables between study groups that could also affect the outcome measures used here. Changes from baseline measures seen at eight weeks were significant, but very small, raising the question of the clinical significance of results.

• The study had baseline sample/group differences of import.
• The study had risk of bias due to no control group, no blinding, no random assignment, and sample characteristics.
• There were substantial differences in treatments used, as well as disease factors between groups compared here.

No firm conclusions can be drawn from these results due to study limitations. Findings aim to show that use of pregabalin for neuropathic pain improves symptoms and  health outcomes. Differences from baseline reported here were small, suggesting lack of meaningful differences from a clinical perspective. Results point to the need for nurses to recognize the difference between statistical and clinical significance in evaluating intervention effects.

To evaluate the effect of pregabalin as an add-on therapy on seizure control, quality of life, and anxiety in patients with brain tumor–related epilepsy.

Pregabalin was added as a first or second add-on drug at 75 mg/day to a maximum of 600 mg/day for specific drugs (i.e., clobazan, lamorigine, levetiracetam, oxcarbazepine, phenobarbital, valproate, and topiramate).

• N = 25 (final sample); 12 patients completed six-month follow-up
• AGE RANGE: 19–72 years
• MALES: 72%, FEMALES: 28%
• KEY DISEASE CHARACTERISTICS: Patients with brain tumor–related epilepsy
• OTHER KEY SAMPLE CHARACTERISTICS: Patients with brain tumor–related epilepsy who had received standard antiepileptic drugs (AED) and who had at least one seizure in the month preceding recruitment  despite AEDs being at the maximum tolerable dose

• SITE: Single site  
• SETTING TYPE: Not specified  
• LOCATION: Center for tumor-related epilepsy

• PHASE OF CARE: Active antitumor treatment

• Descriptive

• Quality of Life in Epilepsy Inventory
• Quality of Life in Cancer
• Hamilton Anxiety Rating Scale
• Zung Self-Rating Depression Scale
• Karnofsky Performance Status
• Seizure diary

The mean dose of pregabalin was 279 mg/day, and the mean follow-up period was 4.1 months. At the end of the follow-up, in the whole intention-to-treat population, nine patients were seizure free, 10 patients had a seizure reduction, and two patients were unchanged. There was a significant difference in the presence or absence of seizure between the baseline and the follow-up visit. There was a significant decrease in anxiety score (p = 0.002) between baseline and last available follow-up visit.

The study showed improvement in anxiety scores with pregabalins, but this is a pilot study with small sample size and a short follow-up period. Future studies with larger sample size and minimum dropout are indicated.

• Small sample (< 30)
• Risk of bias (no control group)
• Risk of bias (no blinding)
• Risk of bias (no random assignment) 
• Risk of bias (no appropriate attentional control condition) 
• Findings not generalizable
• Questionable protocol fidelity

Larger sample size is needed to evaluate the true impact of pregabalin on anxiety among patients with brain tumor–related epilepsy. There are not many implications for nursing because the intervention is drug related.