Publications

2013
Luque-Fernandez MA, Bain P, Gelaye B, Redline S, Williams MA. Sleep-Disordered Breathing and Gestational Diabetes Mellitus [Internet]. Diabetes Care 2013;36:3353-3360. Publisher's VersionAbstract

Recently, sleep-disordered breathing (SDB) has been reported to be associated with the development of gestational diabetes mellitus (GDM). Accordingly, as this is emergent area of research that has significant clinical relevance, the objective of this meta-analysis is to examine the relationship between SDB with GDM. We searched several electronic databases for all of the studies published before January 2013 and reviewed references of published articles. Meta-analytic procedures were used to estimate the unadjusted and BMI-adjusted odds ratios (ORs) using a random effects model. Significant values, weighted effect sizes, and 95% CIs were calculated, and tests of homogeneity of variance were performed. Results from nine independent studies with a total of 9,795 pregnant women showed that SDB was significantly associated with an increased risk of GDM. Women with SDB had a more than threefold increased risk of GDM, with a pooled BMI-adjusted OR 3.06 (95% CI 1.89–4.96). These findings demonstrate a significant association between SDB and GDM that is evident even after considered confounding by obesity. This meta-analysis indicates a need to evaluate the role of early recognition and treatment of SDB early during pregnancy.

dia_care-2013-luque-fernandez-3353-60.pdf
Luque-Fernandez MA, Van Cutsem G, Goemaere E, Hilderbrand K, Schomaker M, Mantangana N, Mathee S, Dubula V, Ford N, Hernan MA, Boulle A. Effectiveness of patient adherence groups as a model of care for stable patients on antiretroviral therapy in Khayelitsha, Cape Town, South Africa [Internet]. PloS one 2013;8:e56088. Press ReleaseAbstract
BACKGROUND: Innovative models of care are required to cope with the ever-increasing number of patients on antiretroviral therapy in the most affected countries. This study, in Khayelitsha, South Africa, evaluates the effectiveness of a group-based model of care run predominantly by non-clinical staff in retaining patients in care and maintaining adherence. METHODS AND FINDINGS: Participation in "adherence clubs" was offered to adults who had been on ART for at least 18 months, had a current CD4 count >200 cells/ml and were virologically suppressed. Embedded in an ongoing cohort study, we compared loss to care and virologic rebound in patients receiving the intervention with patients attending routine nurse-led care from November 2007 to February 2011. We used inverse probability weighting to estimate the intention-to-treat effect of adherence club participation, adjusted for measured baseline and time-varying confounders. The principal outcome was the combination of death or loss to follow-up. The secondary outcome was virologic rebound in patients who were virologically suppressed at study entry. Of 2829 patients on ART for >18 months with a CD4 count above 200 cells/microl, 502 accepted club participation. At the end of the study, 97% of club patients remained in care compared with 85% of other patients. In adjusted analyses club participation reduced loss-to-care by 57% (hazard ratio [HR] 0.43, 95% CI = 0.21-0.91) and virologic rebound in patients who were initially suppressed by 67% (HR 0.33, 95% CI = 0.16-0.67). DISCUSSION: Patient adherence groups were found to be an effective model for improving retention and documented virologic suppression for stable patients in long term ART care. Out-of-clinic group-based models facilitated by non-clinical staff are a promising approach to assist in the long-term management of people on ART in high burden low or middle-income settings.
journal.pone_.0056088-1.pdf
2012
Luque Fernandez MA, Schomaker M, Mason PR, Fesselet JF, Baudot Y, Boulle A, Maes P. Elevation and cholera: an epidemiological spatial analysis of the cholera epidemic in Harare, Zimbabwe, 2008-2009. BMC public healthBMC public healthBMC public health 2012;12:442.Abstract
ABSTRACT: BACKGROUND: In highly populated African urban areas where access to clean water is a challenge, water source contamination is one of the most cited risk factors in a cholera epidemic. During the rainy season, where there is either no sewage disposal or working sewer system, runoff of rains follows the slopes and gets into the lower parts of towns where shallow wells could easily become contaminated by excretes. In cholera endemic areas, spatial information about topographical elevation could help to guide preventive interventions. This study aims to analyze the association between topographic elevation and the distribution of cholera cases in Harare during the cholera epidemic in 2008 and 2009. METHODS: We developed an ecological study using secondary data. First, we described attack rates by suburb and then calculated rate ratios using whole Harare as reference. We illustrated the average elevation and cholera cases by suburbs using geographical information. Finally, we estimated a generalized linear mixed model (under the assumption of a Poisson distribution) with an Empirical Bayesian approach to model the relation between the risk of cholera and the elevation in meters in Harare. We used a random intercept to allow for spatial correlation of neighbouring suburbs. RESULTS: This study identifies a spatial pattern of the distribution of cholera cases in the Harare epidemic, characterized by a lower cholera risk in the highest elevation suburbs of Harare. The generalized linear mixed model showed that for each 100 meters of increase in the topographical elevation, the cholera risk was 30\% lower with a rate ratio of 0.70 (95\% confidence interval=0.66-0.76). Sensitivity analysis confirmed the risk reduction with an overall estimate of the rate ratio between 20\% and 40\%. DISCUSSION: This study highlights the importance of considering topographical elevation as a geographical and environmental risk factor in order to plan cholera preventive activities linked with water and sanitation in endemic areas. Furthermore, elevation information, among other risk factors, could help to spatially orientate cholera control interventions during an epidemic.
luquefernandezbmc-public-health-2012.pdf
2011
Luque Fernandez MA, Mason PR, Gray H, Bauernfeind A, Fesselet JF, Maes P. Descriptive spatial analysis of the cholera epidemic 2008-2009 in Harare, Zimbabwe: a secondary data analysis [Internet]. Trans R Soc Trop Med Hyg 2011;105:38-45. MSF Research Repository (PDF)Abstract
This ecological study describes the cholera epidemic in Harare during 2008-2009 and identifies patterns that may explain transmission. Rates ratios of cholera cases by suburb were calculated by a univariate regression Poisson model and then, through an Empirical Bayes modelling, smoothed rate ratios were estimated and represented geographically. Mbare and southwest suburbs of Harare presented higher rate ratios. Suburbs attack rates ranged from 1.2 (95% Cl = 0.7-1.6) cases per 1000 people in Tynwald to 90.3 (95% Cl = 82.8-98.2) in Hopley. The identification of this spatial pattern in the spread, characterised by low risk in low density residential housing, and a higher risk in high density south west suburbs and Mbare, could be used to advocate for improving water and sanitation conditions and specific preparedness measures in the most affected areas.
Fernandez MA, Cavanillas AB, de Mateo S. Differences in the reproductive pattern and low birthweight by maternal country of origin in Spain, 1996-2006. European journal of public healthEuropean journal of public healthEuropean journal of public health 2011;21:104-8.Abstract
BACKGROUND: Numerous studies have highlighted poorer reproductive and perinatal health outcomes among migrant mothers in developed countries. Due to the fact that no conclusive data is currently available at national level in Spain, this study aimed to explore potential differences by comparing the prevalence of low and multiple live births and the proportion of live births by maternal age and country of origin during 1996-2006. METHODS: A cross-sectional study was conducted using data from the National Statistics Institute. Low birthweight (LBW) was compared by mothers' country of origin using a logistic regression model. Odds ratios (ORs) and their respective 95% confidence intervals (CIs) are stratified by multiplicity and maternal age. Results: LBW was associated with a combination of older maternal age and multiple pregnancies in the case of women who had been born in Europe (EU15). However, this association was not found in women who originated from outside the EU15, mostly from countries who have shown significant emigration to Spain during the last decade. LBW was present among all age groups, in both singleton and multiple births, and in particular Romanian mothers showed the highest OR 2.34 (95% CI 1.20-4.80). CONCLUSION: This study confirms differences in the reproductive pattern and LBW depending on maternal country of origin. These results allow a better understanding of the reproductive pattern and the implications of mothers' country of origin in LBW. Thus, helping health decisions makers to plan future health interventions aimed at reducing the LBW prevalence in Spain.
Luque Fernandez MA, Gutierrez Garitano I, Cavanillas AB. Increased risk of maternal deaths associated with foreign origin in Spain: a population based case-control study. European journal of public healthEuropean journal of public healthEuropean journal of public health 2011;21:292-4.Abstract
In Europe, different studies have identified immigrant women coming from developing countries as a risk group for maternal death. In Spain, an ecological study showed higher maternal mortality rates among foreign mothers compared with Spanish mothers during 2003-04. To examine whether the maternal death risk among foreign mothers in Spain is increased, we performed a population-based matched case-control study. Each case of maternal death during 1999-2006 was matched with four mothers who had given birth during the same year the case occurred. The National Statistics Institute provided the data. The variables in the study were maternal age and country of origin. We used a conditional logistic regression analysis. Adjusted by age, the risk of maternal death was 87% higher among foreign mothers. This study confirms that there is an increased risk of maternal death among foreign mothers in Spain. It would be desirable to analyse the socio-economic and healthcare circumstances surrounding the deaths.
eur_j_public_health-2011-luque_fernandez-292-4.pdf
Luque-Fernandez MA, Lone NI, Gutierrez-Garitano I, Bueno-Cavanillas A. Stillbirth risk by maternal socio-economic status and country of origin: a population-based observational study in Spain, 2007-08. European journal of public healthEuropean journal of public healthEuropean journal of public health 2011;Abstract
BACKGROUND: Socio-economic differences are a major determinant of perinatal outcomes. The impact of low socio-economic status on the risk of stillbirth, and the association between socio-economic status and stillbirth by maternal country of origin at a national level in Spain are unknown. We aimed to analyse the effect of maternal socio-economic status on the risk of stillbirth by maternal country of origin in Spain for the years 2007 and 2008. METHODS: We designed a population-based observational study that included 970 740 live births and 2464 stillbirths from 2007 to 2008. Univariate risk ratios (RRs) of stillbirth were calculated by maternal education, country of origin, age, parity, and gestational age. Adjusted stillbirth RRs were calculated using a generalized linear model with the Poisson family. Then, adjusted attributable risks and aetiological fractions in the population were calculated as measures of impact. RESULTS: Stillbirth rate ranged from 1.0 to 4.7 deaths per 1000 births. The stillbirth risk among mothers having secondary or lower education was double than that of mothers with a tertiary education with an adjusted RR of 2.13 [95% confidence interval (CI): 1.74-2.60]. African mothers, compared with mothers from Spain, showed an adjusted stillbirth RR of 1.75 (95% CI: 1.54-2.00). Discussion: This study confirms the differences of stillbirth risk by maternal socio-economic status. Regardless of socio-economic status, African mothers had the highest risk of stillbirth. These results point out the necessity to reduce factors related to social and health inequalities in perinatal mortality in Spain, and more specifically, to take into consideration the special vulnerability of African mothers.
eur_j_public_health-2011-luque-fernandez-eurpub_ckr074.pdf
Gimenez Duran J, Galmes Truyols AM, Herrera Guibert D, Bonilla Vargas LA, Luque Fernandez MA, Bosch Isabel C, Nicolau Riutort A, Cayla Buqueras J. [Tuberculosis surveillance in the Balearic Islands and characteristics of unreported cases from 2005 to 2007]. Gaceta sanitaria / S.E.S.P.A.SGac Sanit 2011;25:84-6.Abstract
We performed a descriptive study of tuberculosis cases detected by the Epidemiological Surveillance System in the Balearic Islands in the triennium 2005-2007. Our goal was to characterize underreported cases in sociodemographic terms and their contact with primary care. Overall, underreporting of tuberculosis was approximately 20%. Significant factors in multivariate analysis were social marginality (consisting of alcoholism, intravenous drug use or indigence) (aOR: 2.6 [1.2 to 5.3]), contact with primary care (aOR: 3.2 [1.4 to 7.1]), and extrapulmonary tuberculosis (aOR: 5.5[3.2-9.6]). We recommend strengthening notification by hospital specialists through the use of hospital electronic records. Our findings show that the information obtained from the primary care computerized history is helpful in improving the epidemiological surveillance of tuberculosis.
2010
Fernandez MA, Delchevalerie P, Van Herp M. Accuracy of MUAC in the detection of severe wasting with the new WHO growth standards. PediatricsPediatricsPediatrics 2010;126:e195-201.Abstract
OBJECTIVES: The objectives of this study were to estimate the accuracy of using mid-upper-arm circumference (MUAC) measurements to diagnose severe wasting by comparing the new standards from the World Health Organization (WHO) with those from the US National Center for Health Statistics (NCHS) and to analyze the age independence of the MUAC cutoff values for both curves. METHODS: We used cross-sectional anthropometric data for 34,937 children between the ages of 6 and 59 months, from 39 nutritional surveys conducted by Doctors Without Borders. Receiver operating characteristic curves were used to examine the accuracy of MUAC diagnoses. MUAC age independence was analyzed with logistic regression models. RESULTS: With the new WHO curve, the performance of MUAC measurements, in terms of sensitivity and specificity, deteriorated. With different cutoff values, however, the WHO standards significantly improved the predictive value of MUAC measurements over the NCHS standards. The sensitivity and specificity of MUAC measurements were the most age independent when the WHO curve, rather than the NCHS curve, was used. CONCLUSIONS: This study confirms the need to change the MUAC cutoff value from <110 mm to <115 mm. This increase of 5 mm produces a large change in sensitivity (from 16% to 25%) with little loss in specificity, improves the probability of diagnosing severe wasting, and reduces false-negative results by 12%. This change is needed to maintain the same diagnostic accuracy as the old curve and to identify the children at greatest risk of death resulting from severe wasting.
pediatrics-2010-fernandez-e195-201.pdf
Luque Fernandez MA, Bueno Cavanillas A, de Mateo S. Excess of maternal mortality in foreign nationalities in Spain, 1999-2006 [Internet]. European journal of obstetrics, gynecology, and reproductive biologyEuropean journal of obstetrics, gynecology, and reproductive biology 2010;149:52-6. ElservierAbstract
OBJECTIVE: This study aimed to compare maternal mortality by province, autonomous region and mother's country of birth in Spain during 1999-2006. STUDY DESIGN: A cross-sectional ecological study with all live births and maternal mortality cases occurring during 1999-2006 in Spain was done. Data were drawn from the National Statistics Institute (INE) and we used the Movement of Natural Persons (MNP) and death statistics broken down by cause of death. Maternal mortality rates by province, autonomous region and mother's country of birth were calculated. To compare maternal mortality by province, standardised mortality ratios were calculated using an indirect standardisation. The risk of maternal death by autonomous region, age and mother's country of birth was calculated by a Poisson regression. RESULTS: Sub-Saharan nationalities present the highest maternal mortality rates. Adjusted by age and autonomous region, foreign nationalities had 67% higher risk of maternal mortality (RR=1.67; 95%CI=1.22-2.33). Adjusted by mother's country of birth and age, two autonomous regions had a significant mortality excess: Andalusia (RR=1.84; 95%CI=1.32-2.57) and Asturias (RR=2.78 95%CI=1.24-6.24). CONCLUSION: This study shows inequalities in maternal mortality by province, autonomous region and mother's country of birth in Spain. It would be desirable to implement a maternal mortality active surveillance system and the use of confidential qualitative surveys for analysis of socio-economic and healthcare circumstances surrounding deaths. These measures would be invaluable for in-depth understanding and characterisation of a preventable phenomenon such as maternal death.
Duran JG, Fernandez MA, Urrego JR, Gil CL, Vargas LA, Savulescu C, Clerger G, Martinez-Lamas L, Pousa A, Donado Jde M, Herrera D, Martinez MV. [Incidence and risk factors for acute gastroenteritis among pilgrims following the French way to Santiago de Compostela (Spain) in summer 2008]. Gaceta sanitaria / S.E.S.P.A.SGac Sanit 2010;24:487-90.Abstract
OBJECTIVES: To determine the incidence of acute gastroenteritis in pilgrims on St. James' Way, as well as associated risk factors and microbiological characteristics. METHODS: Two studies were designed simultaneously: a cross-sectional study through self-completed questionnaires among pilgrims reaching Santiago, and a case-control study of pilgrims traveling along the Way. Multivariate analysis was performed using logistic regression. RESULTS: In the cross-sectional study, the incidence rate was 23.5 episodes of acute gastroenteritis/10(3) pilgrims-day (95% CI: 18.9-2.4/10(3). In the case-control study, the major risk factors were age <20 years (OR=4.72; 95% CI: 2.16-10.28), traveling in groups (three or more) (OR=1.49; 95% CI: 0.98-2.28), and drinking unbottled water (OR=2.09; 95% CI: 0.91-4.82). The most frequent etiologic agent was norovirus (56%). CONCLUSIONS: Age less than 20 years, traveling in groups and drinking unbottled water were important risk factors for acute gastroenteritis.
2009
Fernandez MA, Cavanillas AB, Dramaix-Wilmet M, Soria FS, de Mata Donado Campos J, Guibert DH. Increase in maternal mortality associated with change in the reproductive pattern in Spain: 1996-2005. J Epidemiol Community HealthJ Epidemiol Community HealthJ Epidemiol Community Health 2009;63:433-8.Abstract
BACKGROUND: In Europe, different studies forecast an increase in maternal mortality in the coming years, associated with advanced maternal age and delay in maternity. This study aims to analyse the age-related trend in the maternal mortality ratio among mothers in Spain for the decade 1996-2005, and to describe the causes of death and associated sociodemographic factors for the years with highest mortality. METHODS: An ecological study on trends, for the age-related trend in the maternal mortality ratio; an indirect standardisation and Poisson regression model was used. For the description of the causes of death, a cross-sectional study was used. RESULTS: Prevalence of live births among mothers aged 35 years and over was 15% higher in Spain than in Europe. The maternal mortality rate increased by 20% (standardised mortality ratio of 1.2, 95% CI 0.9 to 1.4) in 2005 with respect to 1996. The age-related risk of maternal mortality was three times higher (relative risk of 2.90, 95% CI 2.01 to 4.06) among mothers aged 35-44 years versus those aged under 35 years. The highest mortality was detected during 2003-2004. The risk of maternal mortality was higher in foreign mothers. CONCLUSION: This study confirms that there was a change in the maternal mortality trend characterised by an increase in deaths, associated with advanced maternal age, as well as an increase in the prevalence of live births among mothers aged 35 years and over. This change in pattern identifies the need to intensify maternal mortality surveillance by collecting the necessary set of variables that allows investigation of the causes and determinant factors underlying deaths.
Luque Fernandez MA, Bauernfeind A, Jimenez JD, Gil CL, El Omeiri N, Guibert DH. Influence of temperature and rainfall on the evolution of cholera epidemics in Lusaka, Zambia, 2003-2006: analysis of a time series. Trans R Soc Trop Med HygTrans R Soc Trop Med HygTrans R Soc Trop Med Hyg 2009;103:137-43.Abstract
In this study, we aimed to describe the evolution of three cholera epidemics that occurred in Lusaka, Zambia, between 2003 and 2006 and to analyse the association between the increase in number of cases and climatic factors. A Poisson autoregressive model controlling for seasonality and trend was built to estimate the association between the increase in the weekly number of cases and weekly means of daily maximum temperature and rainfall. All epidemics showed a seasonal trend coinciding with the rainy season (November to March). A 1 degrees C rise in temperature 6 weeks before the onset of the outbreak explained 5.2% [relative risk (RR) 1.05, 95% CI 1.04-1.06] of the increase in the number of cholera cases (2003-2006). In addition, a 50 mm increase in rainfall 3 weeks before explained an increase of 2.5% (RR 1.02, 95% CI 1.01-1.04). The attributable risks were 4.9% for temperature and 2.4% for rainfall. If 6 weeks prior to the beginning of the rainy season an increase in temperature is observed followed by an increase in rainfall 3 weeks later, both exceeding expected levels, an increase in the number of cases of cholera within the following 3 weeks could be expected. Our explicative model could contribute to developing a warning signal to reduce the impact of a presumed cholera epidemic.
fernandez_influence_of_temp_cholera_trans.pdf
Luque Fernandez MA, Bauernfeind A. Reply to comment on: Influence of temperature and rainfall on the evolution of cholera epidemics in Lusaka, Zambia, 2003-2006: analysis of a time series. Trans R Soc Trop Med HygTrans R Soc Trop Med HygTrans R Soc Trop Med Hyg 2009;
Luque Fernandez MA, Bueno-Cavanillas A. [Fertility in Spain, 1996-2006: foreign versus Spanish women]. Gaceta sanitaria / S.E.S.P.A.SGac Sanit 2009;23 Suppl 1:67-71.Abstract
OBJECTIVES: To determine fertility trends in Spain and whether women's specific fertility rates differ by age and nationality during the period 1996-2006. METHODS: We performed a population-based, cross-sectional study. Direct standardization was used to compare fertility rates by nationality. Foreign versus Spanish women's fertility rates by age and the period under review were compared by a generalized linear model. The trend by nationality was described by time plots and was analyzed by simple linear regression models. RESULTS: Foreign women had more children (total fertility rate: 2 versus 1.2) and at younger age. The upward trend observed in the fertility of Spanish women (p<0.001) was primarily due to increased fertility in older mothers (35 years and older). The fertility of foreign women aged < or =19 was six times higher than that of Spanish women (rate ratio: 6.00, 95% CI: 2.60-13.86). CONCLUSIONS: The fertility pattern of foreign women differs from that of Spanish women and is mainly characterized by higher fertility, especially in younger women (< or =19 years). This pattern may be associated with social and cultural differences. Prevention and sexual educational policies should be reformulated to take into account the specific sociocultural characteristics of this group and to adapt prevention messages to their cultural context.
2008
Luque Fernandez MA, Galmes Truyols A, Herrera Guibert D, Arbona Cerda G, Sancho Gaya F. Cohort study of an outbreak of viral gastroenteritis in a nursing home for elderly, Majorca, Spain, February 2008 [Internet]. Euro surveillance : bulletin europeen sur les maladies transmissibles = European communicable disease bulletinEuro Surveill 2008;13 ECDC Europe EurosurveillanceAbstract
An outbreak of acute gastroenteritis occurred in a nursing home for elderly in Majorca between 4 and 23 February 2008. To know its aetiology and mechanism of transmission a retrospective cohort study was conducted with a fixed cohort including 146 people (96 residents and 50 employees). The data were collected from clinical histories and through a survey by questionnaire. In total 71 cases were identified (53 residents, 18 employees), corresponding to an overall attack rate (AR) of 48.6%. The consumption of tap water, adjusted by age, sex and consumption of meals provided at the nursing home, presented a relative risk (RR) of 4.03 (95%CI, 1.4-11.4). The microbiological analyses confirmed the presence of norovirus and/or rotavirus in five of the seven stool samples submitted. The slow appearance of cases at the beginning of the outbreak is characteristic of a person to person transmission, while the sudden peak in the middle of the month suggests a common source such as the tap water. We therefore concluded that the outbreak likely originated from two sources: an infected employee of the nursing home and the tap water. The high number of dependent residents most probably facilitated the spread of the outbreak.
luquefernandez-eurosurveillance2008.pdf
Luque Fernandez MA, Bauernfeind A, Palma Urrutia PP, Ruiz Perez I. [Frequency of sexually transmitted infections and related factors in Pweto, Democratic Republic of Congo, 2004]. Gaceta sanitaria / S.E.S.P.A.SGac Sanit 2008;22:29-34.Abstract
OBJECTIVES: To estimate the prevalence of genital ulcer and urethral discharge in Pweto, Democratic Republic of Congo, and to analyze the association between the estimated prevalence and age, marital status, profession, and number of sexual partners. METHODS: We performed a descriptive cross-sectional study through a survey conducted in May 2004 in a representative sample of 106 men in Pweto aged between 15 and 65 years old, with a precision of 9.5%. Questionnaire items about current or previous ulceration and urethral discharge where self-reported and referred to the previous year as of the date of the survey. To study the associations, crude and adjusted odds ratios (OR) were calculated using multivariate logistic regression. RESULTS: The prevalence was 39.6% (95% confidence interval [CI], 30-49) for urethral discharge and 33% (95%CI, 24-42) for genital ulcer. Soldiers were identified as a risk group independently of age, the number of sexual partners during the previous year, and marital status. The multivariate analysis showed an adjusted OR of 3.25 (95%CI, 1.10-9.95) (p < 0.05) for the frequency of urethral discharge in soldiers compared with other professions. CONCLUSIONS: The high prevalence of sexually transmitted infections in Pweto and the associated factors identified prompted the initiation of a controlled condom donation program for soldiers. In conflict situations with a high prevalence of sexually transmitted infections and lack of health services, humanitarian aid organizations should implement prevention activities focused on risk groups.
Luque Fernandez MA. [Trends in the risk of late fetal mortality, prematurity and low birth weight associated with advanced maternal age in Spain [1996-2005]]. Gaceta sanitaria / S.E.S.P.A.SGac Sanit 2008;22:396-403.Abstract
OBJECTIVES: To describe trends in fertility, fetal death rate, prematurity and low birth weight, as well as their association with advanced maternal age, in Spain from 1996 to 2005. METHODS: We performed an ecological study. The association between low birth weight and prematurity with maternal age was analyzed through contingency tables. The pattern of fetal mortality rate was analyzed through direct standardization. To study the risk of late fetal mortality, adjusted by age and prematurity, a Poisson regression model was used. RESULTS: The rates of fertility and late fetal mortality increased in women aged more than 35 years, especially in women aged more than 45 years. The risk of late fetal mortality was 2.7 times higher in women aged 45 years and above (rate ratio, 2.7; 95%CI: 1.8-3), with an etiological fraction of exposure of 69% (95%CI: 55.2-78.6). The prevalence rate of prematurity and low birth weight was three times higher in this age group, with a prevalence rate of prematurity of 2.9 (95%CI: 2.7-3.1) and of low birth weight of 3.1 (95%CI: 2.9-3.3). CONCLUSIONS: The high risk found in women aged more than 45 years is explained by the increase in the proportion of pregnancies within this age group during the period analyzed. Further studies in perinatal epidemiology that analyze the impact of assisted reproduction techniques in pregnancies in older women are required, as well as a national registry of assisted reproduction techniques.
2006
Luque Fernandez MA. [Epidemiology: discipline or method]. Gaceta sanitaria / S.E.S.P.A.SGac Sanit 2006;20:412-3.

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