Portuguese National Health Examination Survey Research Articles

Prevalence Rate of Thalassemia Carriers among Individuals with Microcytosis or Hypochromia in Portugal.

Microcytosis and hypochromia result from deficient hemoglobin synthesis in red blood cells and are easily detected in a complete blood count test. These conditions are mainly due to iron nutritional deficiency, but may also result from some genetic diseases, such as thalassemia. The aim of this study was to determine the contribution of β- and α-thalassemia to these abnormal hematological phenotypes in a representative sample of adult individuals living in Portugal who participated in the first Portuguese National Health Examination Survey (INSEF). Among the 4808 INSEF participants, 204 had microcytosis, hypochromia or both. The corresponding 204 DNAs were screened for changes in the β-globin gene by next-generation sequencing and Sanger sequencing. In addition, α-thalassemia deletions within the α-globin cluster were investigated by Gap-PCR and multiplex ligation-dependent probe amplification. In this selected subgroup of INSEF participants, 54 had α-thalassemia (26%), predominantly caused by the -α3.7kb deletion, and 22 were β-thalassemia carriers (11%) mainly due to point mutations in the β-globin gene previously known in Portugal. Thalassemia trait is a frequent cause of microcytosis or hypochromia in Portugal since this genetic condition was found in 37% of the investigated cases.

Local problem solving in the Portuguese health examination survey: a mixed method study

BackgroundParticipation rates in health surveys, recognized as an important quality dimension, have been declining over the years, which may affect representativeness and confidence in results. The Portuguese national health examination survey INSEF (2015) achieved a participation rate of 43.9%, which is in line with participation rates from other similar health examination surveys. The objective of this article is to describe how local teams of survey personnel conducted the survey, describing strategies used to solve practical survey problems and to try to increase the participation rate.MethodsAfter a literature search, informal interviews were conducted with 14 public health officials from local health examination teams, regional and central authorities. Forty-one of the local staff members (survey personnel) also filled in a short questionnaire anonymously. The interviews and self-administered questionnaires were analysed using mixed methods, informed by thematic analysis.ResultsThe local teams believed that the detailed manual, described as a “cookbook for making a health examination survey”, made it possible to maintain high scientific standards while allowing for improvising solutions to problems in the local context. The quality of the manual, supported by a series of training workshops with the central research and support team, gave the teams the confidence and knowledge to implement local solutions. Motivation and cohesion within the local teams were among the goals of the training process.Local teams felt empowered by being given large responsibilities and worked hard to incite people to attend the examination through a close and persuasive approach.Local teams praised their INSA contacts for being available for assistance throughout the survey, and said they were inspired to try harder to reach participants to please their contacts for interpersonal reasons.ConclusionsThe theory of organizational improvisation or bricolage, which means using limited resources to solve problems, was useful to discuss and understand what took place during INSEF.A detailed manual covering standard procedures, continuous monitoring of the data collection and face-to-face workshops, including role-play, were vital to assure high scientific standards and high participation rates in this health examination survey. Close contacts between the central team and local focal points in all regions and all survey sites were key to accommodating unexpected challenges and innovative solutions.

Association between area- and individual-level socio-economic factors with glycated haemoglobin-Evidence from a Portuguese population-based study.

This study aims to estimate the associations between area-level deprivation and individual-level socio-economic factors, as well as their interaction, with glycated haemoglobin (HbA1c ) levels. We conducted a gamma multilevel regression analysis using individual-level data from the Portuguese National Health Examination Survey and a deprivation index built through factor analysis, at municipality level, with census variables. Living in a municipality with high material deprivation and having a low level of education were independently associated with an increase of 2.3% (95% confidence interval [CI] 0.6, 4.0) and of 1.6% (95% CI 0.6, 2.7) in the mean levels of HbA1c , respectively. The interaction between area material deprivation and individual-level education was not associated with the levels of HbA1c (0.5%, 95% CI -1.3, 2.3). Our findings support the collective resources model that argues that people in less deprived areas have better health because there are more collective resources. The results suggest that to reduce socio-economic inequalities associated with the levels of HbA1c and, consequently, with diabetes, will require attention to the area material deprivation and individual-level education. Upstream social determinants of health are thus highlighted.

Estimation of the 10-Year Risk of Fatal Cardiovascular Disease in the Portuguese Population: Results from the First Portuguese Health Examination Survey (INSEF 2015).

Cardiovascular disease is the leading cause of morbidity and mortality in Portugal and globally. Cardiovascular risk algorithms, namely the SCORE (Systematic Coronary Risk Evaluation), are recommended in the context of cardiovascular disease prevention. Our aim is to estimate and characterize the cardiovascular risk of the Portuguese population aged between 40 and 65 years old, in 2015, using the SCORE algorithm. This study was performed on a subsample of the first Portuguese National Health Examination Survey - INSEF, including all participants between 40 and 65 years old with available data on sex, age, smoking status, total cholesterol and systolic blood pressure (n = 2945). The prevalence of the cardiovascular risk categories were stratified by sex, age group, marital status, educational level, occupational activity, urbanization of living area, region and income. In 2015, about 5.1% and 11.9% of the Portuguese resident population aged between 40 and 65 years old were, respectively, at high and very high risk of having a fatal CV event in the following 10 years. The highest prevalence of very high cardiovascular risk was found in males, individuals aged 60-65 years old, married or living with someone, without any formal education or just with the 1st cycle of basic education and belonging to the less skilled category of the occupational activity (C category) in comparison with the othercorresponding groups. A previous national study found a similar proportion of the population at high/very high cardiovascular risk (19.5% versus 17.1%). Our study is representative of the adult Portuguese population and adopted the European Health Examination Survey procedures, which are essential for future comparisons with other European countries. Some of the limitations of this study include the possible participation bias and the non-calibration of the SCORE algorithm for the Portuguese population. In 2015, a considerable proportion of the Portuguese population aged between 40 and 65 years old had a high or very high risk of developing a fatal cardiovascular event in the next 10 years. Due to the possible overestimation of the cardiovascular risk already reported in other European countries, it will be important to carry out a follow-up study to validate the adequacy of using the SCORE algorithm in the Portuguese population.

Prevalence of anemia in the Portuguese adult population: results from the first National Health Examination Survey (INSEF 2015)

Anemia is a global public health problem with relevant adverse health, social and economic consequences. The objective of this study was to analyze the distribution of the prevalence of anemia in the Portuguese population. This is a cross-sectional population-based study, based on the first Portuguese National Health Examination Survey (INSEF), which included 4812 participants aged 25 to 74 years, with data on hemoglobin levels and self-reported diagnosis of anemia. The socioeconomic status of participants was assessed by education level, employment status and material deprivation. The association between socioeconomic factors and anemia was estimated by adjusted prevalence ratios. The prevalence of anemia overall was 5.8%, 3.1% in men and 8.4% in women. The overall prevalence of moderate–severe anemia was 1.1%. Previously undiagnosed cases represented 92.5%. In men, anemia was associated with age, education, occupation and material deprivation, and in women, with age group and urban typology. Anemia represents a relevant public health issue in Portugal. In women, it is more prevalent among those of childbearing age and older, and in men among older individuals of low socioeconomic status. This information is relevant for developing targeted strategies aimed at the prevention, diagnosis and treatment of anemia.

Collecting Valid and Reliable Data: Fieldwork Monitoring Strategies in a Health Examination Survey

Introduction: Health surveys constitute a relevant information source to access the population’s health status. Given that survey errors can significantly influence estimates and invalidate study findings, it is crucial that the fieldwork progress is closely monitored to ensure data quality. The objective of this study was to describe the fieldwork monitoring conducted during the first Portuguese National Health Examination Survey (INSEF) regarding protocol deviations and key performance indicators (KPI). Methods: Data derived from interviewer observation and from the statistical quality control of selected KPI were used to monitor the four components of the INSEF survey (recruitment, physical examination, blood collection and health questionnaire). Survey KPI included response rate, average time distribution for procedures, distribution of the last digit in a specific measure, proportion of haemolysed blood samples and missing values. Results: Interviewer observation identified deviations from the established protocols, which were promptly corrected. During fieldwork monitoring through KPI, upon implementation of corrective measures, the participation rate increased 2.5-fold, and a 4.4-fold decrease in non-adherence to standardized survey procedures was observed in the average time distribution for blood pressure measurement. The proportion of measurements with the terminal digit of 0 or 5 decreased to 19.6 and 16.5%, respectively, after the pilot study. The proportion of haemolysed samples was at baseline level, below 2.5%. Missing data issues were minimized by promptly communicating them to the interviewer, who could recontact the participant and fill in the missing information. Discussion/Conclusion: Although the majority of the deviations from the established protocol occurred during the first weeks of the fieldwork, our results emphasize the importance of continuous monitoring of survey KPI to ensure data quality throughout the survey.

Effect of lifestyle on blood pressure in patients under antihypertensive medication: An analysis from the Portuguese Health Examination Survey

Introduction and ObjectivesHypertension is one of the main risk factors for disability and death from cardiovascular disease. Current guidelines include initiatives to control blood pressure in hypertensive patients that focus on lifestyle changes. The main objective of this study was to analyze the association between lifestyle and blood pressure in patients under antihypertensive medication. MethodsData collected in the Portuguese National Health Examination Survey (INSEF) were analyzed. Individuals who met INSEF inclusion criteria and reported being under antihypertensive medication in the two weeks prior to the questionnaire were studied. Lifestyle variables (alcohol consumption, smoking, added salt intake, fruit and vegetable consumption, and physical activity) were assessed by questionnaire, and systolic and diastolic blood pressure were measured by physical examination. Associations between lifestyle factors and blood pressure, stratified by gender and adjusted for sociodemographic variables and obesity, were estimated through a multiple linear regression model. ResultsAlcohol consumption (beta=6.31, p=0.007) and smoking (beta=4.72, p=0.018) were positively associated with systolic blood pressure in men. Added salt intake, fruit and vegetable consumption, and physical activity were not associated with blood pressure in men. In women, no association was observed for any behavioral variable. ConclusionsThese conclusions highlight the need in the population under antihypertensive medication, particularly in men, to focus on the fight against high systolic blood pressure in the two modifiable and preventable behaviors of smoking and alcohol consumption.

The first Portuguese National Health Examination Survey (2015): design, planning and implementation

In Health Examination Surveys interview information is complemented with objective information, providing more accurate indicators than self-reported data. We report the study design, planning and implementation of the first Portuguese Health Examination Survey (INSEF). INSEF was a cross-sectional population-based study representative at regional and national level. Individuals aged between 25 and 74 years old, residing in Portugal were selected from the national health users' registry through multi-stage stratified probabilistic sampling. Sample size was set at 4200 individuals. Data was collected in primary care units and included blood pressure, height, weight, hip and waist measurements, blood collection for lipid profile, HbA1c and blood count and a general health questionnaire. European HES procedures were followed. A total of 4911 individuals agreed to participate (43.9% participation rate). Participation rate varied by region, sex and age group, being lower in Lisbon and Tagus Valley (32.8%), for men (41.8%) and for those aged 25-34 years old (36%). INSEF has set up an experienced national and regional structure for HES implementation. Nationally representative quality epidemiological data is now available for public health monitoring, planning and research.

Sociodemographic disparities in hypertension prevalence: Results from the first Portuguese National Health Examination Survey

IntroductionCardiovascular disease is an important cause of death and disability worldwide, and hypertension is responsible for at least 45% of all deaths due to heart disease and 51% of deaths due to stroke. This study aimed to estimate and describe the distribution of prevalence, awareness, treatment and control of hypertension in the Portuguese population in 2015. MethodsA national survey using a representative sample of 4911 individuals residing in Portugal and aged between 25 and 74 years was implemented. Trained nurses performed a health interview and a physical examination, including blood pressure measurement (right arm, three measurements at 1-min intervals). The prevalence of hypertension was stratified by gender, age group, marital status, education, occupation and type of residential area. Associations between hypertension prevalence and sociodemographic factors were assessed using bivariate and multivariate Poisson regression. ResultsThe overall hypertension prevalence was 36.0%. The highest rates were observed in males (39.6%), in individuals aged between 65 and 74 years (71.3%), and in those with low levels of education (62.6%) and with no formal occupation (64.5%). Among hypertensive individuals, 69.8% were aware of their condition and 69.4% were under treatment, of whom 71.3% were controlled. Rates of awareness and medical treatment were significantly higher among women and older individuals. ConclusionsA large majority of the adult Portuguese population are likely to reach blood pressure levels defined as hypertension in adulthood. Significant differences in hypertension prevalence were found according to gender, age and socioeconomic status, which highlights the importance of population strategies in public health policies.

Sociodemographic disparities in hypertension prevalence: Results from the first Portuguese National Health Examination Survey

Cardiovascular disease is an important cause of death and disability worldwide, and hypertension is responsible for at least 45% of all deaths due to heart disease and 51% of deaths due to stroke. This study aimed to estimate and describe the distribution of prevalence, awareness, treatment and control of hypertension in the Portuguese population in 2015. A national survey using a representative sample of 4911 individuals residing in Portugal and aged between 25 and 74 years was implemented. Trained nurses performed a health interview and a physical examination, including blood pressure measurement (right arm, three measurements at 1-min intervals). The prevalence of hypertension was stratified by gender, age group, marital status, education, occupation and type of residential area. Associations between hypertension prevalence and sociodemographic factors were assessed using bivariate and multivariate Poisson regression. The overall hypertension prevalence was 36.0%. The highest rates were observed in males (39.6%), in individuals aged between 65 and 74 years (71.3%), and in those with low levels of education (62.6%) and with no formal occupation (64.5%). Among hypertensive individuals, 69.8% were aware of their condition and 69.4% were under treatment, of whom 71.3% were controlled. Rates of awareness and medical treatment were significantly higher among women and older individuals. A large majority of the adult Portuguese population are likely to reach blood pressure levels defined as hypertension in adulthood. Significant differences in hypertension prevalence were found according to gender, age and socioeconomic status, which highlights the importance of population strategies in public health policies. As doenças cardiovasculares são uma importante causa de morte e incapacidade, sendo que a hipertensão arterial (HTA) é responsável por, pelo menos, 45% da mortalidade por doença cardíaca e 51% por acidente vascular cerebral. Este estudo pretende estimar e descrever a distribuição da prevalência, awareness , tratamento e controlo da HTA na população portuguesa em 2015. Realizou-se um inquérito nacional com uma amostra representativa de 4911 indivíduos, dos 25 aos 74 anos, residentes em Portugal, e que compreendia a realização de uma entrevista de saúde e exame físico que incluía a medição da pressão arterial (braço direito, três medidas, intervalos de um minuto). A prevalência de HTA foi estratificada por sexo, grupo etário, estado civil, educação, ocupação e nível de urbanização. Estimou-se a associação entre a HTA e os fatores sociodemográficos usando regressão de Poisson bivariada e multivariada. A prevalência de HTA foi de 36,0%, sendo mais elevada em indivíduos do sexo masculino (39,6%), entre os 65 e 74 anos (71,3%), com baixo nível de escolaridade (62,6%) e sem ocupação formal (64,5%). Dos indivíduos hipertensos, 69,8% tinham conhecimento da sua condição de saúde, 69,4% faziam medicação anti hipertensora e, destes, 71,3% estavam controlados. A prevalência do conhecimento e tratamento farmacológico da HTA foi mais elevada em mulheres e indivíduos mais velhos. A maioria da população adulta portuguesa poderá vir a ter HTA ao longo da vida. Foram encontradas diferenças importantes na prevalência de HTA de acordo com o sexo, a idade e o nível socioeconómico, o que enfatiza a importância de estratégias populacionais nas políticas de saúde pública.

Do self-reported data accurately measure health inequalities in risk factors for cardiovascular disease?

This study aimed to compare the magnitude of educational inequalities in self-reported and examination-based hypertension and hypercholesterolemia and to assess the impact of self-reported measurement error on health inequality indicators. We used the Portuguese National Health Examination Survey data (n = 4911). The slope index of inequality (SII) and the relative index of inequality (RII) were used to determine the magnitude of absolute and relative education-related inequalities. Among the 25-49-year-old (yo) men, absolute and relative inequalities were smaller for self-reported than for examination-based hypertension (SIIeb = 0.18 vs. SIIsr = - 0.001, p < 0.001; RIIeb = 1.99 vs. RIIsr = 0.86, p = 0.031). For women, the relative inequalities were similar despite differences in self-reported and examination-based hypertension prevalence. For hypercholesterolemia, self-reported relative inequalities were larger than examination-based inequalities among the 50-74-yo men (RIIsr = 2.28 vs. RIIeb = 1.21, p = 0.004) and women (RIIsr = 1.22 vs. RIIeb= 0.87, p = 0.045), while no differences were observed among 25-49-yo. Self-reported data underestimated educational inequalities among 25-49-yo men and overestimated them in older individuals. Inequality indicators derived from self-report should be interpreted with caution, and examination-based values should be preferred, when available.

Oral hygiene habits in Portugal: results from the first Health Examination Survey (INSEF 2015)

Oral health is a determinant for quality of life and preventive behaviours such as regular tooth brushing can reduce the risk of a wide spectrum of oral diseases. Adopting preventive behaviours increases the likelihood of being healthy and can be conditioned by demographic and socio-economic factors.Objective: This study aims to describe preventive oral hygiene behaviours in the Portuguese population and assess their association with sociodemographic and socioeconomic factors.Material and methods: A cross-sectional epidemiologic study was developed using data from the first Portuguese National Health Examination Survey. The target population comprised Portuguese community-dwelling residents aged between 25 and 74 years old. The percentage of individuals who brushed their teeth at least twice a day, provided that once was before sleeping, was considered the indicator showing a preventive behaviour, as this is recommended by the General Directorate of Health in Portugal. Poisson regression was used to identify factors independently associated with this behaviour.Results: Sixty-five per cent of the participants reported tooth brushing as recommended. The prevalence of adoption of this preventive behaviour was higher among those living in urban areas and those who have higher educational level. Results show an association between being male and having low educational level with lesser adoption of preventive oral health behaviours.Conclusion: These findings suggest a need for integrated approaches, from measures tackling social inequalities to actions focused on improving health literacy. It is also important to expand dental healthcare services and improve effective coverage to increase access for rural population.

Differential self-report error by socioeconomic status in hypertension and hypercholesterolemia: INSEF 2015 study.

This study aimed to compare self-reported and examination-based prevalence of hypertension and hypercholesterolemia in Portugal in 2015 and to identify factors associated with the measurement error in self-reports. We used data from the Portuguese National Health Examination Survey (n = 4911), that combines personal interview, blood collection and, physical examination. Sensitivity and specificity of self-reported hypertension and hypercholesterolemia were calculated. Poisson regression was used to estimate prevalence ratios (PRs) of underreport of hypertension and hypercholesterolemia according to sex, age, socioeconomic status (education and income) and general practitioner (GP) consultation in the past year. Sensitivity of self-reports was 69.8% for hypertension and 38.2% for hypercholesterolemia. Underreport of hypertension was associated with male gender (PR = 1.54), lack of GP consultation (PR = 1.70) and being 25-44 years old (PR = 2.45) or 45-54 years old (PR = 2.37). Underreport of hypercholesterolemia was associated with lack of GP consultation (PR = 1.15), younger age (PR = 1.83 for 25-44 age group and PR = 1.52 for 45-54 age group), secondary (PR = 1.30) and higher (PR = 1.27) education. Self-reported data underestimate prevalence of hypertension and hypercholesterolemia. Magnitude of measurement error in self-reports varies by health conditions and population characteristics. Adding objective measurements to self-reported questionnaires improve data accuracy allowing better understanding of socioeconomic inequalities in health.

The social patterning of measurement errors in self-reports: Impact on socioeconomic inequalities estimates

Introduction Reduction of unfair differences in health between socioeconomic groups and countries constitutes an important public health challenge in the 21st century. To monitor progress on this goal, health inequalities are most frequently estimated based on self-reported data from population surveys. However, it has been shown that self-reported data on cardiovascular disease risk factors is prompt to reporting error. If errors occur more often in specific socioeconomic groups (due to under-diagnosis or lower literacy) they are likely to seriously bias health inequality estimates. This study aims at comparing measurement errors between socioeconomic categories in self-reported hypertension, and their consequences on health inequality estimates. Methods We used data from the Portuguese National Health Examination Survey (INSEF), a cross-sectional nationwide study conducted in 2015 on a probabilistic sample (n = 4911) of community-dwelling individuals aged between 25 and 74-years-old. INSEF combines measured biochemical parameters and blood pressure with self-reported data. Self-reported hypertension was defined based on the question: “Do you have any of the following diseases or conditions: hypertension? (Yes/No)”. Examination-based hypertension was defined as having systolic blood pressure of at least 140 mmHg, or diastolic blood pressure of at least 90 mmHg, or using prescribed antihypertensive medication. Participants’ socioeconomic status was measured through the education level (no education/1st cycle of basic education, 2nd cycle of basic education, 3rd cycle of basic education, secondary education and higher education). Inequalities in hypertension between the highest and lowest socioeconomic status groups were measured using relative indexes of inequality (RII) and respective confidence intervals (95% CI), estimated by Poisson regression. Estimates of inequalities were stratified by age and sex, using four population groups (male 25–49-years-old, female 25–49-years-old, male 50–75-years-old, female 50–75-years-old). Results Hypertension was reported by 25.7% [95% CI: 24.0 to 27.4] of participants, while 35.9% [95% CI: 34.2 to 37.5] were considered to have hypertension according to examination-based data. The difference between examination-based and self-reported prevalence was 12.7pp for those with no education/1st cycle of basic education and 4.6pp for those with higher education. Similar educational gradients were observed for both self-reported (RII = 1.87; 95% CI: 1.45 to 2.42) and examination-base (RII = 1.91; 95% CI: 1.60 to 2.28) hypertension, with lowest prevalence of disease among the highly educated. Age- and sex-specific results showed considerable discrepancies in inequality indicators between self-reported and examination-based data. Namely, differences in estimated gradients were more pronounced among 25–49-years-old males, with RII = 0.67 (95% CI: 0.29 to 1.54) for self-reported and RII = 1.90 (95% CI: 1.22 to 2.96) for examination-based hypertension. In 25–49-years-old females inequalities in self-reported hypertension were not statistically significant (RII = 3.18; 95% CI: 0.94 to 10.73), while females with the lowest education were 4.35 (95% CI: 2.60 to 7.27) times more likely to have examination-based hypertension then compared to the most educated. In 50–75 age group educational inequalities in self-reported hypertension were larger than in examination-based for both, male (RII = 1.82; 95% CI: 1.25 to 2.69 vs. RII = 1.40; 95% CI: 1.04 to 1.89) and female (RII = 1.77; 95% CI 1.30 to 2.41 vs. RII = 1.58; 95% CI: 1.22 to 2.04). Conclusions Our results illustrated the significant effect of measurement error in self-reported hypertension on estimates of socioeconomic inequalities. Use of self-reported data led to underestimation of educational inequalities among young and middle-aged individuals and overestimation in older age groups. Inequality indicators derived from self-report should be interpreted with caution.

Inequalities in oral health: Results from the First Portuguese National Health Examination Survey

The Portuguese National Health Examination Survey is developed as a part of the project “Improvement of epidemiological health information to support public health decision and management in Portugal. Towards reduced inequalities, improved health, and bilateral cooperation”, that benefits from a 1.500.000€ Grant from Iceland, Liechtenstein and Norway through the EEA Grants.

Socioeconomic inequalities in obesity prevalence: Portuguese Health Examination Survey results

The Portuguese National Health Examination Survey is developed as a part of the project “Improvement of epidemiological health information to support public health decision and management in Portugal. Towards reduced inequalities, improved health, and bilateral cooperation”, that benefits from a 1.500.000€ Grant from Iceland, Liechtenstein and Norway through the EEA Grants.

The first Portuguese National Health Examination Survey (2015): design, planning and implementation

Background Health Examination Surveys (HES) were interview data is complemented with objective information from physical examination and laboratory analysis, provide more accurate health indicators than self-reported data. Here we report the study design, planning and implementation of the First Portuguese Health Examination Survey (INSEF) developed during 2014-2015. Methods INSEF was developed as a cross-sectional population-based study representative at regional and national level. Development …

Portuguese National Health Examination Survey: Lessons from data collection monitoring

Abstract publicado em: Eur J Public Health. 2015; 25(Suppl 3): 398. doi:10.1093/eurpub/ckv176.069. Disponivel em: http://eurpub.oxfordjournals.org/content/eurpub/25/suppl_3/ckv176.069.full.pdf

Participants’ recruitment: preliminary results of Portuguese National Health Examination Survey

Abstract publicado em: Eur J Public Health. 2015; 25(Suppl 3): 386. doi:10.1093/eurpub/ckv176.035. Disponivel em: http://eurpub.oxfordjournals.org/content/eurpub/25/suppl_3/ckv176.035.full.pdf