Reduced cardiorespiratory fitness in adult survivors of childhood acute lymphoblastic leukemia.

BACKGROUND: Adult survivors of childhood acute lymphoblastic leukemia (ALL) are at increased cardiovascular risk. Studies of factors including treatment exposures that may modify risk of low cardiorespiratory fitness in this population have been limited. PROCEDURE: To assess cardiorespiratory fitness, maximal oxygen uptake (VO2 max) was measured in 115 ALL survivors (median age, 23.5 years; range 18-37). We compared VO2 max measurements for ALL survivors to those estimated from submaximal testing in a frequency-matched (age, gender, race/ethnicity) 2003-2004 National Health and Nutritional Examination Survey (NHANES) cohort. Multivariable linear regression models were constructed to evaluate the association between therapeutic exposures and outcomes of interest. RESULTS: Compared to NHANES participants, ALL survivors had a substantially lower VO2 max (mean 30.7 vs. 39.9 ml/kg/min; adjusted P < 0.0001). For any given percent total body fat, ALL survivors had an 8.9 ml/kg/min lower VO2 max than NHANES participants. For key treatment exposure groups (cranial radiotherapy [CRT], anthracycline chemotherapy, or neither), ALL survivors had substantially lower VO2 max compared with NHANES participants (all comparisons, P < 0.001). Almost two-thirds (66.7%) of ALL survivors were classified as low cardiorespiratory fitness compared with 26.3% of NHANES participants (adjusted P < 0.0001). In multivariable models including only ALL survivors, treatment exposures were modestly associated with VO2 max. Among females, CRT was associated with low VO2 max (P = 0.02), but anthracycline exposure was not (P = 0.58). In contrast, among males, anthracycline exposure ≥ 100 mg/m(2) was associated with low VO2 max (P = 0.03), but CRT was not (P = 0.54). CONCLUSION: Adult survivors of childhood ALL have substantially lower levels of cardiorespiratory fitness compared with a similarly aged non-cancer population.

Atherogenic low density lipoprotein phenotype in long-term survivors of childhood acute lymphoblastic leukemia.

Survivors of childhood acute lymphoblastic leukemia (ALL) have an increased risk of cardiovascular disease. Small density lipoproteins are atherogenic but have not been studied in this population. We conducted a cross-sectional analysis of 110 ALL survivors (mean age, 24.3 years) to determine prevalence of small dense LDL (pattern B) phenotype in ALL survivors and identify associated factors. Lipid subfractions were measured using Vertical Auto Profile-II. Participants with greater than 50% of LDL-cholesterol (LDL-c) in small dense LDL fractions (LDL(3+4)) were classified as LDL pattern B. Visceral and subcutaneous adipose tissue (VAT, SAT) volumes were also measured by computed tomography. While the mean LDL-c level of ALL survivors was 108.7 ± 26.8 mg/dl, 36% (40/110) of survivors had atherogenic LDL pattern B. This pattern was more common in males (26/47; 55%) than in females (14/63; 22%, P = 0.001) and more common in survivors treated with cranial radiotherapy (15/33; 45%) than in those who were treated with chemotherapy alone (25/77; 33%; P = 0.04, adjusted for age, gender, history of hypertension, and smoking history). VAT was associated with atherogenic lipids: LDL pattern B and LDL(3+4) levels. This association was independent of other measures of body fat. We conclude that a substantial proportion of ALL survivors had an atherogenic LDL phenotype despite normal mean LDL-c levels. An atherogenic LDL phenotype may contribute to the increase in cardiovascular mortality and morbidity in this population.

Increasing rates of breast cancer and cardiac surveillance among high-risk survivors of childhood Hodgkin lymphoma following a mailed, one-page survivorship care plan.

BACKGROUND: Hodgkin lymphoma (HL) survivors face substantially elevated risks of breast cancer and cardiovascular disease. They and their physicians are often unaware of these risks and surveillance recommendations. PROCEDURE: A prospective one-arm study was conducted among a random sample of 72 HL survivors, ages 27-55 years, participating in the Childhood Cancer Survivor Study (CCSS) who were at increased risk for breast cancer and/or cardiomyopathy and had not had a screening mammogram or echocardiogram, respectively, within the prior 2 years. A one-page survivorship care plan with recommendations for surveillance was mailed to participants. In addition, survivors' primary physicians were contacted and provided patient-specific information and a web-based Virtual Information Center was made available for both survivors and physicians. Outcomes were assessed by telephone 6 months after the intervention. RESULTS: The survivor participation (62/72; 86%) and 6-month retention (56/61; 92%) rates were high. Tension and anxiety, measured by the Profile of Mood States, did not increase following risk notification; 91% of survivors described their reactions to receiving the information in positive terms. At 6 months, 41% of survivors reported having completed the recommended mammogram; 20% reported having an echocardiogram (females 30%, males 10%). Only 29% of survivors visited the website. Nine physicians enrolled, and none used the study resources. CONCLUSION: A mailed, personalized survivorship care plan was effective in communicating risk and increasing compliance with recommended medical surveillance. Internet- and telephone-based strategies to communicate risk were not utilized by survivors or physicians.

Insulin resistance and risk factors for cardiovascular disease in young adult survivors of childhood acute lymphoblastic leukemia.

PURPOSE: To determine the prevalence of insulin resistance and other risk factors for cardiovascular disease (CVD) in young adult survivors of childhood acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: In this cross-sectional evaluation of 118 survivors of childhood ALL (median age, 23.0 years; range, 18 to 37 years), insulin resistance was estimated using the homeostasis model for assessment of insulin resistance (HOMA-IR). Sex-specific comparisons were made with a cohort of 30- to 37-year-old individuals from the same region participating in the Dallas Heart Study (DHS, N = 782). ALL survivors were stratified by treatment with and without cranial radiotherapy (CRT). RESULTS: Female ALL survivors had a significantly higher HOMA-IR (CRT, mean 4.6, 95% CI, 3.6 to 5.7; no CRT, mean 3.3, 95% CI, 2.8 to 3.8) in comparison with DHS women (mean 2.4, 95% CI, 2.2 to 2.7). Eighty percent of women treated with CRT had at least three of six CVD risk factors, and they were significantly more likely to have three or more risk factors compared with DHS women (odds ratio [OR], 5.96; 95% CI, 2.15 to 16.47). Male ALL survivors had a significantly higher HOMA-IR (CRT, mean 4.0, 95% CI, 2.8 to 5.6; no CRT, mean 3.4, 95% CI, 2.9 to 3.9) in comparison with DHS men (mean 2.3, 95% CI, 2.1 to 2.6), but were not more likely to have multiple CVD risk factors. CONCLUSION: ALL survivors had an increased prevalence of insulin resistance in comparison with a cohort of older individuals from the same community. Importantly, women treated with CRT seem to have an increased prevalence of multiple CVD risk factors, warranting close monitoring and risk-reducing strategies.

Adequacy of antidote stocking in British Columbia hospitals: the 2005 Antidote Stocking Study.

BACKGROUND: Inadequate hospital stocking and the unavailability of essential antidotes is a worldwide problem with potentially disastrous repercussions for poisoned patients. Research indicates minimal progress has been made in the resolution of this issue in both urban and rural hospitals. In response to this issue the British Columbia Drug and Poison Information Centre developed provincial antidote stocking guidelines in 2003. We sought to determine the compliance with antidote stocking in BC hospitals and any factors associated with inadequate supply. METHODS: A 2-part survey, consisting of hospital demographics and antidote stocking information, was distributed in 2005 to all acute care hospital pharmacy directors in BC. The 32 antidotes examined (21 deemed essential) and the definitions of adequacy were based on the 2003 BC guidelines. Availability was reported as number of antidotes stocked per hospital and proportion of hospitals stocking each antidote. For secondary purposes, we assessed factors potentially associated with inadequate stocking. RESULTS: Surveys were completed for all 79 (100%) hospitals. A mean of 15.6+/-4.9 antidotes were adequately stocked per hospital. Over 90% of hospitals had adequate stocks of N-acetylcysteine, activated charcoal, naloxone, calcium salts, flumazenil and vitamin K; 71%-90% had adequate dextrose 50% in water (D50W), ethyl alcohol or fomepizole, polyethylene glycol electrolyte solution, protamine sulfate, and cyanide antidotes; 51%-70% had adequate folic acid, glucagon, methylene blue, atropine, pralidoxime, leucovorin, pyridoxine, and deferoxamine; and <50% had adequate isoproterenol and digoxin immune Fab. Only 7 (8.9%) hospitals sufficiently stocked all 21 essential antidotes. Factors predicting poor stocking included small hospital size (p < 0.0001), isolation (p = 0.01) and rural location (p < 0.0001). CONCLUSION: Although antidote stocking has improved since the implementation of the 2003 guidelines, essential antidotes are absent in many BC hospitals. Future research should focus on determining the reasons for this situation and the effects of corrective interventions.

Delayed dystonia following pimozide overdose in a child.

BACKGROUND: Pimozide overdose has rarely been reported in children. In adults, pimozide intoxication may cause seizures, extrapyramidal and anticholinergic effects, hypotension, QTc prolongation and torsades de pointes. We report dystonia, hypotension and drowsiness following pimozide ingestion in a child. CASE REPORT: An alert 18-month-old presented to hospital 40 minutes after ingesting up to 6 mg (0.5 mg/kg) of pimozide. Vital signs: BP 91/62 mmHg, HR 130/min, RR 26/min, temperature 97.2 degrees F (36.2 degrees C). She received gastric lavage and activated charcoal. One hour later, her QTc interval was 420 msec, HR 150. She remained asymptomatic until 12 hours post-ingestion, when she developed drooling, tongue thrusting and drowsiness. BP was 75/40, HR 150, QTc 440 msec. BP increased to 95/50 after a bolus of normal saline. Her dystonia subsided over the next 12 hours without treatment. Drowsiness and tachycardia persisted until 40 hours post-ingestion. QTc interval at this time was 370 msec. Patient recovered without sequelae. CONCLUSION: Pimozide overdose in children may be associated with delayed onset of symptoms, including dystonia.

Salty broth for salicylate poisoning? Adequacy of overdose management advice in the 2001 Compendium of Pharmaceuticals and Specialties.

BACKGROUND: The Compendium of Pharmaceuticals and Specialties (CPS) is a collection of monographs written by pharmaceutical companies and published by the Canadian Pharmacists Association. The CPS is widely available and is consulted frequently by Canadian physicians. We examined overdose management advice contained in the CPS to see whether it reflects current standards. METHODS: We restricted our review to 10 classes of medication for which an overdose is frequently fatal: acetaminophen, beta-blockers, calcium-channel blockers, digoxin, lithium, opioids, salicylates, tricyclic antidepressants, theophylline and valproic acid. A panel of 3 toxicologists arrived at a consensus on indicated, contraindicated and futile interventions for each of these classes of drug. Monographs were then rated for their inclusion of essential interventions as excellent (listed all interventions and unique supportive care issues and gave correct and complete indications), good (listed the key interventions and gave correct and complete indications), fair (listed the key indications but failed to give proper indications) or poor (failed to list the key interventions). Monographs were also rated on how well they warned against contraindicated interventions as excellent (did not advocate any futile or contraindicated treatments and warned against contraindicated treatments), good (did not advocate any futile or contraindicated treatments), fair (did not advocate any contraindicated treatments but did list some simple futile treatments) or poor (advocated contraindicated or complicated futile treatments, such as unnecessary hemodialysis). We also considered whether the monograph would allow a clinician to manage an overdose, whether it served to refresh one's memory and whether it was simply misleading or dangerous. RESULTS: We reviewed 119 monographs, of which 25 (21%) were adequate to allow a clinician to manage an overdose. Another 25 monographs were not adequate to allow a clinician to manage an overdose but would serve to refresh the memory regarding key management points. Sixty monographs (50%) contained misleading or dangerous advice. Nine monographs (8%) did not fall into any of these categories. In terms of listing essential interventions, 61 monographs (51%) were poor, 35 (29%) were fair, 22 (18%) were good, and 1 (1%) was excellent. For warning against contraindicated interventions, 57 monographs (48%) were poor, 9 (8%) were fair, 51 (43%) were good, and 2 (2%) were excellent. INTERPRETATION: Overdose management advice in the CPS is inadequate in most cases and is misleading or dangerous in half of the monographs examined. These sections should be omitted or rewritten to reflect current standards of care. Physicians should refer to authoritative sources (e.g., current toxicology texts, computerized databases or local poison control centres) for poisoning management advice.