Alvaro Javier Idrovo

Safety of botulinum toxin type A among children with spasticity secondary to cerebral palsy: a systematic review of randomized clinical trials

Objective: To assess the safety of botulinum toxin type A for children with cerebral palsy using data from randomized clinical trials. Data sources: A search was conducted of MEDLINE database for the period January 1990 to February 2008. A complementary search was carried out of references from previous reviews. From 122 articles, 20 randomized clinical trials were selected for the review. Review methods: Two authors independently assessed eligibility of the studies and methodological quality of those according to CONSORT guidelines. For each adverse effect, relative risk was calculated, and when more than one study reported adverse effects, a meta-analysis was carried out. Sensitivity analyses with different continuity corrections factors were performed when zero cases were reported in a study arm. Results: There were 882 participants in the 20 studies included in the meta-analysis. Six studies reported zero adverse effects. Thirty-five different adverse events were reported. Botulinum toxin type A use was related to respiratory tract infection, bronchitis, pharyngytis, asthma, muscle weakness, urinary incontinence, falls, seizures, fever and unspecified pain. Two deaths were reported in the study with higher person-time follow-up (relative risk (RR) 4.69, 95% confidence interval (CI) 0.23—95). Conclusions: Botulinum toxin type A has a good safety profile during the first months of use. However the occurrence of adverse events is more frequent among children with cerebral palsy than individuals with other conditions. Severe adverse events are potentially related with the use of botulinum toxin type A, but data are sparse and additional study is required to clarify the causal relation.

Determinants of Performance of Health Systems Concerning Maternal and Child Health: A Global Approach

Aims To assess the association of social determinants on the performance of health systems around the world. Methods A transnational ecological study was conducted with an observation level focused on the country. In order to research on the strength of the association between the annual maternal and child mortality in 154 countries and social determinants: corruption, democratization, income inequality and cultural fragmentation, we used a mixed linear regression model for repeated measures with random intercepts and a conglomerate-based geographical analysis, between 2000 and 2010. Results Health determinants with a significant association on child mortality(<1year): higher access to water (βa Quartile 4(Q4) vs Quartile 1(Q1) = -6,14; 95%CI: -11,63 to -0,73), sanitation systems, (Q4 vs Q1 = -25,58; 95%CI: -31,91 to -19,25), % measles vaccination coverage (Q4 vs Q1 = -7.35; 95%CI: -10,18 to -4,52), % of births attended by a healthcare professional (Q4 vs Q1 = -7,91; 95%CI: -11,36 to -4,52) and a % of the total health expenditure (Q3 vs Q1 = -2,85; 95%CI: -4,93 to -0,7). Ethnic fragmentation (Q4 vs Q1 = 9,93; 95%CI: -0.03 to 19.89) had a marginal effect. For child mortality<5 years, an association was found for these variables and democratization (not free vs free = 11,23; 95%CI: -0,82 to 23,29), out-of-pocket expenditure (Q1 vs Q4 = 17,71; 95%CI: 5,86 to 29,56). For MMR (Maternal mortality ratio), % of access to water for all the quartiles, % of access to sanitation systems, (Q3 vs Q1 = -171,15; 95%CI: -281,29 to -61), birth attention by a healthcare professional (Q4 vs Q1 = -231,23; 95%CI: -349,32 to -113,15), and having corrupt government (Q3 vs Q1 = 83,05; 95%CI: 33,10 to 133). Conclusions Improving access to water and sanitation systems, decreasing corruption in the health sector must become priorities in health systems. The ethno-linguistic cultural fragmentation and the detriment of democracy turn out to be two factors related to health results.

Exposure to pesticide mixtures and DNA damage among rice field workers

Abstract This study describes the use of pesticides mixtures and their potential association with comet assay results in 223 rice field workers in Colombia. Thirty-one pesticides were quantified in blood, serum, and urine (15 organochlorines, 10 organophosphorus, 5 carbamates, and ethylenethiourea), and the comet assay was performed. Twenty-four (77.42%) pesticides were present in the workers. The use of the maximum-likelihood factor analysis identified 8 different mixtures. Afterwards, robust regressions were used to explore associations between the factors identified and the comet assay. Two groups of mixtures— α-benzene hexachloride (α-BHC), hexachlorobenzene (HCB), and β-BHC (β: 1.21, 95% confidence interval [CI]: 0.33–2.10) and pirimiphos-methyl, malathion, bromophos-methyl, and bromophos-ethyl (β: 11.97, 95% CI: 2.34–21.60)—were associated with a higher percentage of DNA damage and comet tail length, respectively. The findings suggest that exposure to pesticides varies greatly among rice field workers.

Biodiversity and depressive symptoms in Mexican adults: Exploration of beneficial environmental effects

INTRODUCTION Depression is a highly prevalent illness among adults, and it is the second most frequently reported mental disorder in urban settings in México. Exposure to natural environments and its components may improve the mental health of the population. OBJECTIVE To evaluate the association between biodiversity indicators and the prevalence of depressive symptoms among the adult population (20 to 65 years of age) in México. MATERIALS AND METHODS Information from the Encuesta Nacional de Salud y Nutrición 2006 (ENSANUT 2006) and the Compendio de Estadísticas Ambientales 2008 was analyzed. A biodiversity index was constructed based on the species richness and ecoregions in each state. A multilevel logistic regression model was built with random intercepts and a multiple logistic regression was generated with clustering by state. RESULTS The factors associated with depressive symptoms were being female, self-perceived as indigenous, lower education level, not living with a partner, lack of steady paid work, having a chronic illness and drinking alcohol. The biodiversity index was found to be inversely associated with the prevalence of depressive symptoms when defined as a continuous variable, and the results from the regression were grouped by state (OR=0.71; 95% CI = 0.59-0.87). CONCLUSIONS Although the design was cross-sectional, this study adds to the evidence of the potential benefits to mental health from contact with nature and its components.

Social epidemiology of a large outbreak of chickenpox in the Colombian sugar cane producer region: a set theory-based analysis

There are few social epidemiologic studies on chickenpox outbreaks, although previous findings suggested the important role of social determinants. This study describes the context of a large outbreak of chickenpox in the Cauca Valley region, Colombia (2003 to 2007), with an emphasis on macro-determinants. We explored the temporal trends in chickenpox incidence in 42 municipalities to identify the places with higher occurrences. We analyzed municipal characteristics (education quality, vaccination coverage, performance of health care services, violence-related immigration, and area size of planted sugar cane) through analyses based on set theory. Edwards-Venn diagrams were used to present the main findings. The results indicated that three municipalities had higher incidences and that poor quality education was the attribute most prone to a higher incidence. Potential use of set theory for exploratory outbreak analyses is discussed. It is a tool potentially useful to contrast units when only small sample sizes are available.

[Monitoring the Paraguayan epidemiological dengue surveillance system (2009-2011) using Benford's law].

INTRODUCTION Dengue is the most widespread arbovirus worldwide. In Paraguay, it reappeared in 1988-1989, with one of the largest epidemic outbreaks occurring in 2011. OBJECTIVE To evaluate the performance of the dengue epidemiological surveillance system in Paraguay between 2009 and 2011. MATERIALS AND METHODS We conducted an ecological study with secondary epidemiological surveillance data. We analyzed notified cases of the disease based on the distribution expected by Benfords law. To this end, we used the first and second digits from the global records stratified by region, season, population density, indicators of housing conditions and heads of cattle. RESULTS The epidemiological surveillance system performed better during non-epidemic periods and in the states with better housing conditions and fewer heads of cattle. CONCLUSION Given that a difference in the performance existed, we recommended that the system remains operating at the same high alert level even during periods when fewer cases are expected. The technology used by the method proposed to monitor the notification of cases is easy to transfer to operational staff.

Work conditions and morbidity among coal miners in Guachetá, Colombia: the miners´ perspective

INTRODUCTION Investigations in Colombia about work and health conditions in coal mining are scarce and few have focused on the perception of the exposed population and their behaviors in response to inherent risks. OBJECTIVE To determine the association between work conditions and the perception of morbidity among coal miners in Guachetá, Cundinamarca. MATERIALS AND METHODS A cross-sectional study was performed with 154 workers selected randomly from the total registered with the municipality. Information about social and demographic characteristics and work and health conditions in the mines was gathered. The prevalence was estimated for respiratory, musculoskeletal and auditory disorders. The associations between certain work conditions, and events with a prevalence over 30% were explored using bivariate and multivariate analyses with Poisson regressions with robust variance. RESULTS Workers were mostly men. Ages ranged from 18 to 77 years. Most frequently reported health problems were: back pain (46.1 %), pain in an upper limb (40.3%), pain in a lower limb (34.4 %), and respiratory (17.5 %) and auditory problems (13.6 %). Significant differences in perception were found depending on time on the job and underground or ground work conditions. CONCLUSIONS The most recognized risks were those associated with musculoskeletal disorders since they were closer in time to the work performed (time discount). Some actions to identify psychological traits are proposed in order to improve risk perception among coal miners.

Access to medicines among internally displaced and non-displaced people in urban areas in Colombia

This study analyzes access to medicines among displaced and non-displaced populations in urban areas in Bucaramanga, Colombia. A household survey was carried out to study access to medicines for self-reported and medically diagnosed health conditions. Multiple Poisson regression with robust variance was used to determine factors associated with access to medicines. Two thousand and sixty individuals from 514 families participated. Only 29.1% (95%CI: 22.04-37.08) of the individuals in the sample with prescriptions and 44.3% (95%CI: 40.42-48.25) with self-reported needs for pharmacotherapy were taking medicines. Greater access was associated with the perceived severity of the illness, higher income, having a health center nearby and not perceiving barriers in accessing services. Social security affiliation and being displaced were not related. Social security coverage alone does not have an effect on access to medicines because it does not include essential medicines that correspond to the health needs of this population. Resolving administrative and geographical barriers is likely to improve access to medicines.

Letter to the editor on 'Safety of botulinum toxin type A among children with spasticity secondary to cerebral palsy: a systematic review of randomized clinical trials'.

In the published version of our paper ‘Safety of botulinum toxin type A among children with spasticity secondary to cerebral palsy: a systematic review of randomized clinical trials’, there was one error. This was detected by Dr Marie Blackmore from the Centre for Cerebral Palsy/ Curtin University of Technology. Australia. We acknowledge her advice and help. The correct forest plot for muscle weakness is shown here in Figure 1. In addition, after the submission to Clinical Rehabilitation but before the publication of our systematic review, two new randomized clinical trials fulfilling the inclusion criteria were published. This is a frequent phenomenon in science since the fast growth of evidence, and an excellent opportunity to actualize and to test the generated hypotheses expressed in the paper. In our article the main conclusions were the toxin was related to respiratory tract infection, bronchitis, pharyngytis, asthma, muscle weakness, urinary incontinence, falls, seizures, fever and unspecified pain. We indicated the need to study the potential association with severe adverse events as deaths. In addition we suggested that botulinum toxin type A has a good safety profile during the first months of use. One of these clinical trials, described in two publications with different outcomes, did not report adverse effects. However, in a very well-designed, randomized, double-blind, placebo-controlled study with two years follow-up (5548 persons-week), Moore et al. evaluated the efficacy and safety of botulinum toxin type A (Dysport) in the treatment of leg spasticity among 58 children with cerebral palsy. The participants received injections of up to 30mU/kg every three months if their clinical manifestations required it. An interesting methodological aspect of this clinical trial was the fact that an independent safety committee monitored adverse effects data. With the different adverse effects reported we recalculated the pooled relative risks and 95% confidence intervals of each event. Findings of the new analyses are summarized in Table 1. Note that there are two types of results: (1) significant relative risk with narrower confidence interval: pharyngytis, localized pain, falls, seizures,

Evaluation of exposure of auto painters to organic solvents in the city of Bogota

INTRODUCTION Painters of automobiles are exposed to pure and mixed solvents that have been associated with neurological effects and carcinogenic mutations. OBJECTIVE To characterize the health and work conditions of individuals who are occupationally exposed to organic solvents used in sheet metal and auto body shops in Bogota. MATERIALS AND METHODS Descriptive, cross-sectional study that characterizes the health and work conditions of individuals exposed to organic solvents in sheet metal and auto body shops in Bogota. A group exposed to the solvents was compared to an unexposed group. Air concentrations of benzene, toluene and xylene (BTX) were determined, individual questionnaires were administered and phenylmercapturic, hippuric and ortho- and para-methylhippuric acids were measured in urine. The results of the measurements and the questionnaires were correlated to determine the exposure panorama. RESULTS For the three BTX metabolites, statistically significant differences (p<0.001) were found between the population exposed to the solvents and the unexposed population. For the exposed population, positive correlations were found between toluene in air and hippuric acid in urine (rho=0.82) and between xylene in air and o-methylhippuric acid in urine (rho=0.76). Hippuric acid values exceeded permissible levels in 11 workers and p-methylhippuric acid exceeded permissible levels in 8 workers. None of the phenylmercapturic values exceeded the limit. CONCLUSION Auto painters are exposed to high levels of organic solvents at the workplace and do not have adequate industrial health and safety conditions to perform their jobs.