Safety monitoring of treatment in bipolar disorder in a tertiary care setting in Sri Lanka and recommendations for improved monitoring in resource limited settings.

BACKGROUND: Safety monitoring of medicines is essential during therapy for bipolar disorder (BD). We determined the extent of safety monitoring performed according to the International Society for Bipolar Disorders (ISBD) guidelines in patients with BD attending the main tertiary care psychiatry clinics in Sri Lanka to give realistic recommendations for safety monitoring in resource limited settings. METHODS: Patients diagnosed with BD on mood stabilizer medications for more than 1 year were recruited. Data were collected retrospectively from clinic and patient held records and compared with the standards of care recommended by ISBD guidelines for safety monitoring of medicines. RESULTS: Out of 256 patients diagnosed with BD, 164 (64.1%) were on lithium. Only 75 (45.7%) had serum lithium measurements done in the past 6 months and 96 (58.5%) had concentrations recorded at least once in the past year. Blood urea or creatinine was measured in the last 6 months only in 30 (18.3%). Serum electrolytes and thyroid-stimulating hormone (TSH) concentrations were measured in the last year only in 34 (20.7%) and 30 (18.3%) respectively. Calcium concentrations were not recorded in any patient. None of the patients on sodium valproate (n = 119) or carbamazepine (n = 6) had blood levels recorded to establish therapeutic concentrations. Atypical antipsychotics were prescribed for 151 (59%), but only 13 (8.6%) had lipid profiles and only 31 (20.5%) had blood glucose concentration measured annually. Comorbidities experienced by patients influenced monitoring more than the medicines used. Patients with diabetes, hypothyroidism and hypercholesterolemia were more likely to get monitored for fasting blood glucose and (p < 0.001), TSH (p < 0.001) and lipid profiles (p < 0.001). Lithium therapy was associated with TSH monitoring (p < 0.05). Therapy with atypical antipsychotics was not associated with fasting blood glucose or lipid profile monitoring (p > 0.05). A limitation of the study is that although some tests were performed, the results may not have been recorded. CONCLUSIONS: Safety monitoring in BD was suboptimal compared to the ISBD guidelines. ISBD standards are difficult to achieve in resource limited settings due to a multitude of reasons. Realistic monitoring benchmarks and recommendations are proposed for methods to improve monitoring in resource limited settings based on our experience.

Risk-Benefit assessment of infant exposure to lithium through breast milk: a systematic review of the literature.

The continuation of lithium while breastfeeding is a controversial topic, and clinical recommendations vary. A systematic review was completed of available data on lithium and breastfeeding to determine the degree of lithium exposure through breast milk and assess the potential risk to the infant. Databases, including PubMed MEDLINE, Embase, PsycINFO, Web of Science, Scopus, and Cochrane CENTRAL Register of Controlled Trials databases, were searched for articles on lithium and breastfeeding from the start dates of the databases through December 2018. Articles were included if the report included at least one maternal serum/plasma and/or breast milk lithium concentration and one infant serum/plasma lithium concentration. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Twelve articles, all case reports, were selected for inclusion out of 441 articles that were found and 230 that were reviewed from the search. Data are limited on the safety of lithium continuation while breastfeeding. Among the adverse effects reported, it is difficult to differentiate poor outcomes from factors affecting infant health, concomitant medications, and gestational lithium exposure. Recommendations on whether to continue lithium while breastfeeding must be personalized to the individual woman and her infant.

Methodology for rapid assessment of blood lithium levels in ultramicro volumes of blood plasma for applications in personal monitoring of patients with bipolar mood disorder.

Bipolar disorder (BD) is a common mental health condition, characterized by extreme changes in mood, energy, and behavior. BD is often managed through mood-stabilizing medications, of which lithium formulations remain the most reliable and effective at reducing the risk of suicide. To achieve adequate and consistent efficacy, lithium concentrations need to be maintained within a narrow therapeutic range (0.4 to 1.2 mmol / L). Because of its narrow therapeutic index, long-term lithium therapy is associated with serious side effects and risks of toxicity. It is believed that the availability of a personal blood lithium analyzer would benefit patients who are on lithium treatment. We detail the results of a spectrophotometric method performed on ultramicro volumes to determine blood plasma lithium concentrations as compared with reference measurements of flame photometry, and validated in samples of unknown lithium content. Applying multiple linear regression, lithium concentrations could be determined in a rapid manner using full-range spectra or triwavelength data. Both techniques highly correlated with reference standards and could predict lithium levels accurately (R2 = 0.794214 and RMSEP = 0.209584, and R2 = 0.863921 and RMSEP = 0.167524, respectively). Therefore, this method can be a useful for rapid assessment of blood lithium in nonlaboratory settings i.e., general practices, hospital clinics, and community health centers by healthcare professionals and/or by patients. Future work will now focus on completion of a miniaturized and integrated system that will deliver a portable and personal lithium-monitoring device.

Population pharmacokinetic model of lithium and drug compliance assessment.

Population pharmacokinetic analysis of lithium during therapeutic drug monitoring and drug compliance assessment was performed in 54 patients and 246 plasma concentrations levels were included in this study. Patients received several treatment cycles (1-9) and one plasma concentration measurement for each patient was obtained always before starting next cycle (pre-dose) at steady state. Data were analysed using the population approach with NONMEM version 7.2. Lithium measurements were described using a two-compartment model (CL/F=0.41Lh-1, V1/F=15.3L, Q/F=0.61Lh-1, and V2/F = 15.8L) and the most significant covariate on lithium CL was found to be creatinine clearance (reference model). Lithium compliance was analysed using inter-occasion variability or Markovian features (previous lithium measurement as ordered categorical covariate) on bioavailability parameter. Markov-type model predicted the lithium compliance in the next cycle with higher success rate (79.8%) compared to IOV model (65.2%) and reference model (43.2%). This model becomes an efficient tool, not only being able to adequately describe the observed outcome, but also to predict the individual drug compliance in the next cycle. Therefore, Bipolar disorder patients can be classified regarding their probability to become extensive or poor compliers in the next cycle and then, individual probabilities lower than 0.5 highlight the need of intensive monitoring, as well as other pharmaceutical care measurements that might be applied to enhance drug compliance for a better and safer lithium treatment.

How appropriate is therapeutic drug monitoring for lithium? Data from the Belgian external quality assessment scheme.

BACKGROUND: Lithium remains a mainstay in the management of mood disorders. As with many psychotropic drugs, lithium treatment requires continuous observation for adverse effects and strict monitoring of serum concentrations. The present study aimed to assess the appropriateness of lithium assays used by Belgian laboratories, and to evaluate acceptability of their clinical interpretations. METHODS: Nine in-house serum samples spiked with predetermined concentrations of lithium were distributed to 114 participants in the Belgian external quality assessment scheme. Laboratories were requested to report the assay technique, lithium measurements and interpretations with regard to measured concentrations. Inter/intramethod imprecision and bias were reported and acceptability of clinical interpretations was assessed. The intramethod variability was evaluated by selecting methods used by 6 laboratories or more. Flame photometry (IL 943) was considered as the reference method. RESULTS: Laboratories returned assay results using colorimetry (69.3%), ion selective electrode (15.8%), flame photometry (8.8%), atomic absorption spectroscopy (5.2%) or mass spectrometry (0.9%). Lithium concentrations were systematically higher when measured with the Vitros assay (median bias: 4.0%), and were associated with consecutive biased interpretations. In contrast, the Thermo Scientific Infinity assay showed a significant negative bias (median bias: 9.4%). 36.0% of laboratories reported numerical values below their manufacturer cut-off for the blank sample; 16.6% of these laboratories detected residual lithium concentrations. CONCLUSIONS: The present study revealed assay-related differences in lithium measurements and their interpretations. Overall, there appeared to be a need to continue EQA of therapeutic drug monitoring for lithium in Belgium.

Safe lithium use in a non-psychiatric versus a psychiatric inpatient veterans affairs hospital setting: a retrospective assessment.

OBJECTIVE: This study examined practices for monitoring lithium in a non-psychiatric versus psychiatric inpatient setting at a Veterans Affairs facility. METHODOLOGY: This retrospective chart review included veterans who had an active order of lithium during their non-psychiatric or psychiatric inpatient stay over the time period of January 2000 to September 2011. Chi-square tests were used for data analysis. Frequency of appropriate lithium monitoring was assessed using standards set by the National Institute for Clinical Excellence and British Association for Psychopharmacology guidelines for bipolar disorder. RESULTS: A total of 200 patients (100 for each group) were included in the final analysis. Psychiatric inpatients had more frequent serum lithium levels measured during inpatient stay (p = 0.0002), whereas nonpsychiatric patients had more frequent renal monitoring (p = 0.0001). Non-psychiatric patients were significantly more likely to have action taken upon abnormal safety assessments (p = 0.0075). CONCLUSIONS: Our results demonstrate significant differences between the non-psychiatric and psychiatric inpatient settings in respect to monitoring lithium. The frequency of serum lithium level monitoring in both groups was below the level set by both the National Institute for Clinical Excellence and British Association for Psychopharmacology guidelines. Additionally, frequency of corrective measures in both settings was low, indicating a need for improvement in this area.

InstaRead Lithium System.

A finger-stick office test for measuring serum lithium concentrations.

Natriuretic effect of caffeine: assessment of segmental sodium reabsorption in humans.

In order to assess the intrarenal mechanisms responsible for the natriuretic action of caffeine, the renal clearances of (51)Cr-EDTA [used as a measure of glomerular filtration rate (GFR)] and lithium (used as an index of end-proximal fluid delivery) were measured in eight healthy males before (control period) and immediately after (experimental period) a 400 mg oral dose of caffeine (given over 90 min) or placebo. In caffeine-treated subjects, the fractional excretion of sodium rose from 1.00+/-0.25% in the control period to 1.47+/-0.18% in the experimental period, while corresponding values on the placebo day were 1.04+/-0.16% and 0.70+/-0.07% respectively. GFR was unchanged following either caffeine or placebo. When compared with the placebo day, caffeine caused increases in lithium clearance (experimental period values: caffeine, 37+/-1 ml/min; placebo, 28+/-2 ml/min; P <0.001), the fractional excretion of lithium (caffeine, 34+/-1%; placebo, 26+/-2%; P <0.001) and the sodium/lithium clearance ratio (used as an index of the fraction of sodium delivered to the distal nephron that escapes reabsorption therein: caffeine, 4.4+/-0.3%; placebo, 2.8+/-0.2%; P <0.001). These results suggest that reduced fractional sodium reabsorption in both the proximal tubule and the distal nephron contributes to the acute natriuretic effect of caffeine. The data also confirm the importance of controlling caffeine intake when investigating renal function using lithium clearance.

Therapeutic drug monitoring of mood stabilizers in Medicaid patients with bipolar disorder.

OBJECTIVE: The authors' goal was to determine the extent and pattern of blood serum monitoring of mood stabilizers in Medicaid patients with bipolar disorder. METHOD: Data were drawn from a Medicaid medical claims data set from Pittsburgh and the surrounding region. The authors identified bipolar patients using lithium, valproate, and carbamazepine (N = 718) and then examined the patient demographic, diagnostic, and service use variables associated with therapeutic drug monitoring. RESULTS: A substantial proportion of lithium users (36.5%), valproate users (42.4%), and carbamazepine users (42.2%) with bipolar disorder diagnoses did not receive therapeutic drug level testing during the 12-month study period. Carbamazepine users who were male or in the 30-49-year age range were significantly less likely to be tested for serum drug level. Lithium users who did not receive partial-hospitalization psychiatric services and valproate users who received mental health case management were also less likely to be tested for serum drug level. Over one-half of the lithium users (54.1%) did not receive thyroid function tests, and few (4.2%) received renal function tests. Patients who did receive tests for serum drug level were likely to receive the other recommended tests. CONCLUSIONS: Many Medicaid patients with bipolar disorder received no therapeutic drug monitoring. Patient sociodemographic characteristics contributed little to explaining this omission, although some types of service utilization were related to rates of serum drug level testing.

Appropriateness of the use of serum lithium assays.

The performance of 222 lithium assays was studied in a psychiatric hospital to determine if their use was appropriate and therapeutically beneficial. Charts of all patients whose serum lithium levels were measured in a month were reviewed to determine whether the assays were indicated, whether they were performed correctly, and whether the dosage was adjusted appropriately. Of the assays reviewed, 16 percent were performed for inappropriate indications and 98 percent were drawn at correct times. Of 157 assays that should not have resulted in a dosage change, 8 changes were made; of 63 assays that should have resulted in a dosage change, only 23 changes were made. Inappropriate orders for assays cost the hospital +5016 per year. If routine serum lithium assay monitoring is changed to a three-month frequency, the total cost savings would be +16,632 per year. Clinical pharmacists with specialized knowledge of clinical pharmacokinetics should work with physicians and treatment teams in monitoring serum drug assays to ensure appropriateness of assay request, more complete interpretation of results, and proper follow up.

Assessment of red cell sodium transport in essential hypertension.

Abnormal erythrocyte Na+ transport has been reported in patients with essential hypertension and some first-degree relatives. The two major techniques now employed for estimating Na+ transport--Na+/Li+ countertransport and Na+/K+ cotransport--are rather intricate and time consuming. Furthermore, the precise nature of the transport processes being measured is not clear. We have developed a simpler, more direct technique based on measurement of 22Na+ accumulation by erythrocytes. 22Na+ uptake by red cells from patients with essential hypertension averages twice normal. Indeed, of 21 patients with essential hypertension, only 2 patients had values within the upper end of the normal range. In 12 patients with secondary hypertension and no family history of essential hypertension, erythrocyte 22Na+ accumulation was within normal limits. Control experiments indicate that our technique for estimating red cell 22Na+ uptake is highly reproducible and shows little day-to-day variation. This procedure for the assessment of erythrocyte Na+ transport should be useful in differential diagnosis and the presymptomatic identification of individuals genetically prone to essential hypertension.

Methodological assessment of assays for red cell sodium concentration and sodium-dependent lithium efflux.

Assays for red cell sodium concentration and sodium-dependent lithium efflux were studied from a methodological point of view. The technical errors for sodium concentration--based on concurrent analysis of randomized blind duplicate samples--was 2.5% and for lithium efflux 6.4%. Based on repeated measures in the same individual, the assays were stable over time and reproducible; individual differences at a mean interval of 16 days were not significantly different. A wait of two hours from time of phlebotomy to analysis yielded a slight (3.8%) but significant fall in the sodium concentration; no further change was found at four hours. No change occurred in the lithium efflux over time. A standardized breakfast containing 664 mg sodium did not affect the measurements when fasting and three-hour postprandial levels were compared. The ratios of intra- to inter-individual variance were small--0.04 for red cell sodium concentration and 0.09 for sodium-stimulated lithium efflux. These assays appear to be reproducible and stable and can be applied in large scale field trials.

Double-blind procedure: an assessment in a study of lithium prophylaxis.

Fifty-seven patients with primary affective disorder who were in a double-blind outpatient study to evaluate the prophylaxis of lithium were questioned as to whether they believed they were receiving lithium or placebo. Research nurses who were 'blind' to the patients' medication and a close relative living with each patient were also questioned. Nearly all patients (96%) said they beleived they were receiving lithium, ascribing this belief in 63% of the cases to a perceived improvement in condition. In only 14% of the cases on lithium was the presence of side-effects implicated in the patients' beliefs. One of the three nurses had a correct guess rate in excess of chance expectancy. All nurses tended to be more accurate in their guesses in the cases of patients who had been in prophylactic trials of over 15 months' duration than for patients with briefer periods in the study. Patients' relatives were, as a group, extremely accurate, their correct guess rate exceeding chance expectancy at the 0-001 level.