The syndrome of motor restlessness--a treatable but under-recognised disorder

Prevalence of depression or depressive state in patients with restless legs syndrome: A systematic review and meta-analysis

Restless legs syndrome (RLS) is a common sleep-related disorder characterized by limb discomfort and the urge to move them when at rest, especially in the evening or at night. Although depression is often linked to various conditions, no systematic review has assessed depression prevalence in patients with RLS after the latest diagnostic criteria revision. This systematic review and meta-analysis aimed to investigate the depression and depressive state prevalence among patients with RLS. We systematically searched databases up to November 2022 and performed meta-analyses of the depression prevalence using a random-effects model and a meta-regression analysis to explore the relationship between the prevalence and severity of depression and factors such as age and RLS severity. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we analyzed 24 studies with 2039 patients. The pooled depression or depressive state prevalence, mostly defined by questionnaire scores, was 30.39 %. Nine studies reported the proportion of patients taking antidepressants (pooled rate: 3.41 %). No specific factors related to the prevalence or severity of depression were identified in patients with RLS. These findings highlight the significant prevalence of depression and underscore the need for future research with standardized diagnostic interviews and consistent methodologies across multi-site studies.

A trial of midazolam vs diphenhydramine in prophylaxis of metoclopramide-induced akathisia

STUDY OBJECTIVE

The study aimed to evaluate the effects of midazolam and diphenhydramine for the prevention of metoclopramide-induced akathisia.

METHODS

This randomized, double-blind, and controlled trial aimed to investigate coadministered midazolam vs diphenhydramine in the prophylaxis of metoclopramide-induced akathisia. Patients 18 to 65 years of age who presented to the emergency department with primary or secondary complaints of nausea and/or moderate to severe vascular-type headache were eligible for this study. Patients were randomized to one of the fallowing 3 groups: (1) metoclopramide 10 mg + midazolam 1.5 mg; (2) metoclopramide 10 mg + diphenhydramine 20 mg; (3) metoclopramide 10 mg + placebo. Metoclopramide was administered as a 2-minute bolus infusion. Midazolam, diphenhydramine, and normal saline solution were administered as a 15-minute slow infusion. The whole procedure was observed; and akathisia and sedation scores and vital changes were recorded.

RESULTS

There were significant differences among groups with respect to akathisia (P = .016) and sedation (P < .001). The midazolam group showed the lowest mean akathisia score but the highest mean sedation score. Akathisia scores of the diphenhydramine group were not different from placebo. There were significant differences among groups in terms of changes in mean vital findings such as respiration rates, pulse rates, and systolic blood pressures (P < .05). There were no significant difference among groups in terms of changes in mean diastolic blood pressures (P = .09).

CONCLUSION

Coadministered midazolam reduced the incidence of akathisia induced by metoclopramide compared to placebo but increased the rate of sedation. No difference was detected from diphenhydramine. Routine coadministered 20 mg diphenhydramine did not prevent metoclopramide-induced akathisia.

Development of a simplified instrument for the diagnosis and grading of akathisia in a cohort of patients receiving prochlorperazine

Akathisia is a common side-effect of dopamine receptor D2 antagonists that often remains undiagnosed. Conventional diagnostic and grading instruments are cumbersome and can be difficult to remember and to use. To facilitate the Emergency Department (ED) assessment of acute drug-induced akathisia, I sought to derive and evaluate a simplified instrument using the database compiled from three prior studies of acute drug-induced akathisia. These studies had used a conventional Long instrument in the prospective assessment of 360 adult ED patients aged 17-65 years who received intravenous prochlorperazine (10 mg) in the treatment of headache or nausea and vomiting. The Short instrument was derived from the Long instrument using the Wilcoxon z-test to identify the individual findings most strongly associated with the diagnosis of akathisia. I then retrospectively applied the Short instrument to the cohort and used pairwise analyses to compare results obtained from both instruments. Sensitivity, specificity and receiver operating characteristic curves were used to analyze the impact of instrument form on diagnostic accuracy. The Long criteria diagnosed akathisia in 118 (32.8%; 95% confidence interval [CI] 28.0%-37.9%) patients and the Short diagnosed akathisia in 120 (33.3%; 95% CI 28.5%-38.5%). When akathisia was characterized categorically as either absent or present, the Short criteria agreed with the Long in 358 cases (99.4%; 95% CI 98.0%-99.9%). Treating the diagnoses established by the Long criteria as the gold standard, the Short instrument had a sensitivity of 100.0% (95% CI 96.9%-100%) and a specificity of 99.2% (95% CI 97.0%-99.9%). Regarding the accuracy of categorizing akathisia into four severity grades, the Short scale agreed in 325 of 360 cases (90.3%; 95% CI 86.7%-93.1%) and misgraded 35 cases (9.7%; 95% CI 6.9%-13.3%), 34 of which fell within one grade of the Long scale. The Short instrument is highly accurate in diagnosing acute drug-induced akathisia, in comparison with the Long criteria, in the ED setting. The Short instrument also provides fairly accurate grading of akathisia severity. This simplified instrument should facilitate the detection and treatment of akathisia in the ED.

Diphenhydramine in the treatment of akathisia induced by prochlorperazine

Dopamine D(2) antagonists are known to induce akathisia, the emergency management of which remains undetermined. We sought to evaluate the effectiveness of diphenhydramine in the treatment of akathisia induced by 10 mg intravenous prochlorperazine. This prospective, open-label, uncontrolled study evaluated a cohort of akathisic adult Emergency Department patients who were participating in a series of three studies of acute akathisia at an academic medical center. Each subject received intravenous diphenhydramine, with akathisia measurements (graded from 0-17 points) performed just before and 30 min after infusion. Mean scores were calculated using descriptive statistical analyses. The effect of treatment was evaluated using the paired t-test. For the 87 akathisic patients, the mean score before treatment was 9.8 +/- 3.6, and after treatment was 1.2 +/- 2.6, a mean reduction of 8.5 +/- 3.8 (95% confidence interval [CI], 7.8 to 9.4; p < 0.0001). In conclusion, intravenous diphenhydramine rapidly reduces signs and symptoms of acute akathisia induced by prochlorperazine.

Intravenous administration of prochlorperazine by 15-minute infusion versus 2-minute bolus does not affect the incidence of akathisia: a prospective, randomized, controlled trial

STUDY OBJECTIVE

We sought to compare the rate of akathisia after administration of intravenous prochlorperazine as a 2-minute bolus or 15-minute infusion.

METHODS

We conducted a prospective, randomized, double-blind study in the emergency department of a central-city teaching hospital. Patients aged 18 years or older treated with prochlorperazine for headache, nausea, or vomiting were eligible for inclusion. Study participants were randomized to receive 10 mg of prochlorperazine administered intravenously by means of 2-minute push (bolus group) or 10 mg diluted in 50 mL of normal saline solution administered by means of intravenous infusion during a 15-minute period (infusion group). The main outcome was the number of study participants experiencing akathisia within 60 minutes of administration. Akathisia was defined as either a spontaneous report of restlessness or agitation or a change of 2 or more in the patient-reported akathisia rating scale and a change of at least 1 in the investigator-observed akathisia rating scale. The intensity of headache and nausea was measured with a 100-mm visual analog scale.

RESULTS

One hundred patients were enrolled. One study participant was excluded after protocol violation. Seventy-three percent (73/99) of the study participants were treated for headache and 70% (70/99) for nausea. In the bolus group, 26.0% (13/50) had akathisia compared with 32.7% (16/49) in the infusion group (Delta=-6.7%; 95% confidence interval [CI] -24.6% to 11.2%). The difference between the bolus and infusion groups in the percentage of participants who saw a 50% reduction in their headache intensity within 30 minutes was 11.8% (95% CI -9.6% to 33.3%). The difference in the percentage of patients with a 50% reduction in their nausea was 12.6% (95% CI -4.6% to 29.8%).

CONCLUSION

A 50% reduction in the incidence of akathisia when prochlorperazine was administered by means of 15-minute intravenous infusion versus a 2-minute intravenous push was not detected. The efficacy of prochlorperazine in the treatment of headache and nausea likewise did not appear to be affected by the rate of administration, although no formal statistical comparisons were made.

Diphenhydramine for the prevention of akathisia induced by prochlorperazine: a randomized, controlled trial

STUDY OBJECTIVES

The utility of intravenous prochlorperazine as an antiemetic agent and abortive therapy for headache may be limited by the frequent occurrence of akathisia, the distressing effects of which have been shown to disrupt patient care. We tested the hypothesis that adjuvant diphenhydramine reduces the incidence of akathisia induced by prochlorperazine.

METHODS

This randomized, double-blind, placebo-controlled trial was conducted in the emergency department of an academic tertiary care medical center with an annual census of 95,000 emergency patient visits. We enrolled a convenience sample of 100 adult patients who received 10 mg of intravenous prochlorperazine for the treatment of nausea/vomiting or headache. Subjects were randomly assigned to receive a 2-minute infusion of prochlorperazine with either 50 mg of diphenhydramine or placebo. The incidence of akathisia at 1 hour was measured by using explicit diagnostic criteria. To measure the influence of treatment on sedation, the subjects noted, on a 100-mm visual analog scale, their degree of sedation before and after treatment.

RESULTS

Akathisia developed in 18 (36%) of 50 subjects in the control group and in 7 (14%) of 50 subjects in the diphenhydramine group, a 61% relative reduction. The addition of adjunct diphenhydramine resulted in an absolute reduction of 22% in the incidence of akathisia (95% confidence interval [CI] 6% to 38%; P = .01). The odds ratio for akathisia with the use of adjuvant diphenhydramine was 0.39 (95% CI 0.18 to 0.85). Mean sedation scores increased 12 mm after infusion of prochlorperazine alone (95% CI 3 to 21 mm) compared with a 33-mm increase after infusion of prochlorperazine with adjuvant diphenhydramine (95% CI 24 to 42 mm). The 12-mm difference between the groups was statistically significant (95% CI 9 to 34 mm, P < .001).

CONCLUSION

Adjuvant diphenhydramine reduces the incidence of akathisia induced by prochlorperazine and is associated with an increase in sedation.

Prochlorperazine induces akathisia in emergency patients

STUDY OBJECTIVE

Prochlorperazine (PCZ), a commonly used antiemetic and analgesic agent, is known to cause akathisia. The incidence of akathisia after a single 10-mg dose of intravenous PCZ has not been prospectively evaluated. We determined the incidence and severity of PCZ-induced akathisia at 1 hour and the incidence of delayed akathisic symptoms at 48 hours.

METHODS

This prospective controlled study evaluated a convenience sample of 140 adult patients at a 400-bed, academic, tertiary-care medical center with an annual emergency department census of 95,000 patient visits. One hundred patients who received intravenous PCZ for the treatment of severe headache or vomiting constituted the PCZ group. Forty patients receiving nonakathisic intravenous therapy (eg, saline solution or antibiotics) served as control subjects. Patients were excluded if they had preexisting motor disorders (eg, restless-leg syndrome or Parkinson's disease) or if they recently had received any medication with extrapyramidal, anticholinergic, sedative, or antiakathisic properties. All patients underwent an akathisia assessment before and 1 hour after receiving their respective intravenous medications. An established scale was used to detect the presence of akathisia and grade its severity as mild, moderate, or severe. The delayed development of akathisic symptoms within 48 hours also was measured in the PCZ group.

RESULTS

Akathisia developed in 44 (44%) of the patients receiving PCZ within 1 hour (95% confidence interval, 34% to 54%). The akathisia was graded as mild, moderate, and severe in 14, 22, and 8 subjects, respectively. Delayed symptoms suggestive of akathisia developed in 3 other patients within 48 hours. None of the 40 control subjects developed akathisia.

CONCLUSION

Single-dose intravenous PCZ frequently induced akathisia within 1 hour of administration. Acute akathisia was not observed in patients receiving intravenous saline solution or antibiotics. The delayed development of akathisia symptoms 48 hours after a single dose of intravenous PCZ was uncommon.