Christa Scheidt-Nave

The challenge of comprehensively mapping children's health in a nation-wide health survey: Design of the German KiGGS-Study

BackgroundFrom May 2003 to May 2006, the Robert Koch Institute conducted the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). Aim of this first nationwide interview and examination survey was to collect comprehensive data on the health status of children and adolescents aged 0 to 17 years.Methods/DesignParticipants were enrolled in two steps: first, 167 study locations (sample points) were chosen; second, subjects were randomly selected from the official registers of local residents. The survey involved questionnaires filled in by parents and parallel questionnaires for children aged 11 years and older, physical examinations and tests, and a computer assisted personal interview performed by study physicians. A wide range of blood and urine testing was carried out at central laboratories. A total of 17 641 children and adolescents were surveyed – 8985 boys and 8656 girls. The proportion of sample neutral drop-outs was 5.3%. The response rate was 66.6%.DiscussionThe response rate showed little variation between age groups and sexes, but marked variation between resident aliens and Germans, between inhabitants of cities with a population of 100 000 or more and sample points with fewer inhabitants, as well as between the old West German states and the former East German states. By analysing the short non-responder questionnaires it was proven that the collected data give comprehensive and nationally representative evidence on the health status of children and adolescents aged 0 to 17 years.

Vitamin D status and health correlates among German adults

Objective:To analyze vitamin D status based on serum 25-hydroxyvitamin D (25OHD) measurements, its determinants and health correlates in a representative sample of German adults.Subjects:A total of 1763 men and 2267 women, 18- to 79-year old, who participated in the representative German National Health Interview and Examination Survey 1998 and the integrated German Nutrition Survey.Results:The median vitamin D intake from both diet and supplements did not meet the recommended level of 5 μg/day, in either men (2.8 μg/day) or women (2.3 μg/day). Altogether 80.9% of men and 88.5% of women had vitamin D intakes below this level. Moderate (12.5–25 nmol/l serum 25OHD levels) and mild (25–50 nmol/l) vitamin D deficiency was prevalent in the adult population in Germany, even in younger age groups. Overall, 57% of men and 58% of women had vitamin D levels below 50 nmol/l. Among 65- to 79-year-old women, the proportion amounted to 75%, even during the sunnier half of the year. In sex-specific multiple linear regression models, independent determinants of serum 25OHD levels consistently included season, vitamin D intake from both diet and supplements, physical activity and living in a partnership. In addition, age and current menopausal hormone use contributed to the model among women, as opposed to time of day of blood sampling and body mass index (marginally) among men. Significantly lower serum 25OHD levels were observed in women with hypertension, cardiovascular diseases and noninsulin-treated diabetes mellitus as well as in men with insulin-treated diabetes mellitus compared with nonaffected participants.Conclusions:Vitamin D deficiency is a public health issue in Germany. We identified a number of determinants with potential for primary prevention of vitamin D deficiency. Risk and benefits of preventive actions need to be examined in further studies.

German health interview and examination survey for adults (DEGS) - design, objectives and implementation of the first data collection wave

BackgroundThe German Health Interview and Examination Survey for Adults (DEGS) is part of the recently established national health monitoring conducted by the Robert Koch Institute. DEGS combines a nationally representative periodic health survey and a longitudinal study based on follow-up of survey participants. Funding is provided by the German Ministry of Health and supplemented for specific research topics from other sources.Methods/designThe first DEGS wave of data collection (DEGS1) extended from November 2008 to December 2011. Overall, 8152 men and women participated. Of these, 3959 persons already participated in the German National Health Interview and Examination Survey 1998 (GNHIES98) at which time they were 18–79 years of age. Another 4193 persons 18–79 years of age were recruited for DEGS1 in 2008–2011 based on two-stage stratified random sampling from local population registries. Health data and context variables were collected using standardized computer assisted personal interviews, self-administered questionnaires, and standardized measurements and tests. In order to keep survey results representative for the population aged 18–79 years, results will be weighted by survey-specific weighting factors considering sampling and drop-out probabilities as well as deviations between the design-weighted net sample and German population statistics 2010.DiscussionDEGS aims to establish a nationally representative data base on health of adults in Germany. This health data platform will be used for continuous health reporting and health care research. The results will help to support health policy planning and evaluation. Repeated cross-sectional surveys will permit analyses of time trends in morbidity, functional capacity levels, disability, and health risks and resources. Follow-up of study participants will provide the opportunity to study trajectories of health and disability. A special focus lies on chronic diseases including asthma, allergies, cardiovascular conditions, diabetes mellitus, and musculoskeletal diseases. Other core topics include vaccine-preventable diseases and immunization status, nutritional deficiencies, health in older age, and the association between health-related behavior and mental health.

Incidence of limb fracture across Europe: Results from the European prospective osteoporosis study (EPOS)

Abstract: The aim of this population-based prospective study was to determine the incidence of limb fracture by site and gender in different regions of Europe. Men and women aged 50–79 years were recruited from population registers in 31 European centers. Subjects were invited to attend for an interviewer-administered questionnaire and lateral spinal radiographs. Subjects were subsequently followed up using an annual postal questionnaire which included questions concerning the occurrence of new fractures. Self-reported fractures were confirmed where possible by radiograph, attending physician or subject interview. There were 6451 men and 6936 women followed for a median of 3.0 years. During this time there were 140 incident limb fractures in men and 391 in women. The age-adjusted incidence of any limb fracture was 7.3/1000 person-years [pyrs] in men and 19 per 1000 pyrs in women, equivalent to a 2.5 times excess in women. Among women, the incidence of hip, humerus and distal forearm fracture, though not ‘other’ limb fracture, increased with age, while in men only the incidence of hip and humerus fracture increased with age. Among women, there was evidence of significant variation in the occurrence of hip, distal forearm and humerus fractures across Europe, with incidence rates higher in Scandinavia than in other European regions, though for distal forearm fracture the incidence in east Europe was similar to that observed in Scandinavia. Among men, there was no evidence of significant geographic variation in the occurrence of these fractures. This is the first large population-based study to characterize the incidence of limb fracture in men and women over 50 years of age across Europe. There are substantial differences in the descriptive epidemiology of limb fracture by region and gender.

Clinical Grading of Spinal Osteoporosis: Quality of Life Components and Spinal Deformity in Women with Chronic Low Back Pain and Women with Vertebral Osteoporosis

Clinical consequences of osteoporotic vertebral fractures, such as back pain, functional limitations, and impairment of mood, are often cited as justification for prevention and therapy. But these symptoms are poorly characterized, and a clinical grading system is not available. The aim of this study was to compare clinical measures for spinal deformation and quality of life components between patients with osteoporosis and patients with chronic low back pain (CLBP) and to determine the relationship between spinal deformation and quality of life components. A total of 130 female patients (63 osteoporotic patients, 65 ± 7.9 years, and 77 CLBP patients, 56 ± 6.5 years) had a standardized interview on quality of life components (pain, activities of daily life, mood) and clinical measures of spinal deformation (height reduction [HR], distance from occiput to wall [DOW], and distance from iliac crest to ribs [DIR]). Spinal X‐rays were reviewed in all patients for the evidence of vertebral fractures. In osteoporotic patients, vertebral deformity was quantified by the spine deformity index (SDI) on X‐rays. It was assessed whether subgroups could be identified by a combination of indices for spinal deformation (SDI, HR, DOW) using a cluster analysis. Back pain was a major complaint in both groups, without differences in pain intensity and frequency. Impairment of general well being and mood was found in about one‐third of the patients in both groups. Independent of age, the disability score was significantly higher in patients with osteoporosis than in patients with CLBP. Both groups differed with respect to clinical measures of spinal deformity (HR, DOW, DIR). Among osteoporotic patients, parameters of quality of life were not linearly related to the degree of radiologically assessed vertebral deformity, but osteoporotic patients with two or more vertebral fractures tended to have more functional limitations than those with only one fracture. There was, however, a significant linear relationship between components of quality of life (disability score, pain) and clinical measures of spinal deformation (HR, DOW, DIR). The osteoporotic patients were subdivided into three clusters. The first group was characterized by low spinal deformation (↓SDI, ↓HR, ↓DOW) and little impairment of quality of life. The second group had significantly greater spinal deformation (↑SDI, ↑HR, ↑DOW) and significantly more pain and functional limitations. The third group was characterized by increased kyphosis, mainly caused by nonskeletal dysfunction (↓SDI, ↓HR, ↑DOW), but pain and functional limitations were impaired to the same degree as in the second group with severe skeletal spinal deformation. We conclude that with respect to quality of life components, functional limitation is the most specific to spinal osteoporosis and is related to clinical measures of spinal deformation. Furthermore, spinal deformation and the clinical course of osteoporosis appears to be insufficiently reflected by radiological indices of vertebral deformity (such as SDI) alone. For grading the disease and for therapeutical concepts, radiological measures and clinical evaluation should be considered in combination.

Population-based geographic variations in dxa bone density in Europe: The evos study

The purpose of this study was to investigate variations in bone density between 16 European populations, 13 of which were participants in the European Vertebral Osteoporosis Study (EVOS). Men and women aged 50–80 years were recruited randomly from local population registers, stratified in 5-year age bands. The other three centres recruited similarly. Random samples of 20–100% of EVOS subjects were invited for dual-energy X-ray absorptiometry (DXA) densitometry of the lumbar spine and/or proximal femur using Hologic, Lunar or Norland pencil beam machines or, in one centre, a Sopha fan-beam machine. Cross-calibration of the different machines was undertaken using the European Spine Phantom prototype (ESPp). Highly significant differences in mean bone density were demonstrated between centres, giving rise to between-centre SDs in bone density that were about a quarter of a population SD. These differences persisted when centres using Hologic machines and centres using Lunar machines were considered separately. The centres were ranked differently according to whether male or female subjects were being considered and according to site of measurement (L2–4, femoral neck or femoral trochanter). As expected, bone mineral density (BMD) had a curvilinear relationship with age, and apparent rates of decrease slowed as age advanced past 50 years in both sexes. In the spine, not only did male BMD usually appear to increase with age, but there was a highly significant difference between centres in the age effect in both sexes, suggesting a variability in the impact of osteoarthritis between centres. Weight was consistently positively associated with BMD, but the effects of height and armspan were less consistent. Logarithmic transformation was needed to normalize the regressions of BMD on the independent variates, and after transformation, all sites except the femoral neck in females showed significant increases in SD with age. Interestingly, the effect of increasing weight was to decrease dispersion in proximal femur measurements in both sexes, further accentuating the tendency in women for low body mass index to be associated with osteoporosis as defined by densitometry. It is concluded that there are major differences between BMD values in European population samples which, with variations in anthro-pometric variables, have the potential to contribute substantially to variations in rates of osteoporotic fracture risk in Europe.

Prevalent Vertebral Deformity Predicts Incident Hip though not distal Forearm Fracture: Results from the European Prospective Osteoporosis Study

Abstract: The presence of a vertebral deformity increases the risk of subsequent spinal deformities. The aim of this analysis was to determine whether the presence of vertebral deformity predicts incident hip and other limb fractures. Six thousand three hundred and forty-four men and 6788 women aged 50 years and over were recruited from population registers in 31 European centers and followed prospectively for a median of 3 years. All subjects had radiographs performed at baseline and the presence of vertebral deformity was assessed using established morphometric methods. Incident limb fractures which occurred during the follow- up period were ascertained by annual postal questionnaire and confirmed by radiographs, review of medical records and personal interview. During a total of 40 348 person-years of follow-up, 138 men and 391 women sustained a limb fracture. Amongst the women, after adjustment for age, prevalent vertebral deformity was a strong predictor of incident hip fracture, (rate ratio (RR) = 4.5; 95% CI 2.1–9.4) and a weak predictor of ‘other’ limb fractures (RR = 1.6; 95% CI 1.1–2.4), though not distal forearm fracture (RR = 1.0; 95% CI 0.6–1.6). The predictive risk increased with increasing number of prevalent deformities, particularly for subsequent hip fracture: for two or more deformities, RR = 7.2 (95% CI 3.0–17.3). Amongst men, vertebral deformity was not associated with an increased risk of incident limb fracture though there was a nonsignificant trend toward an increased risk of hip fracture with increasing number of deformities. In summary, prevalent radiographic vertebral deformities in women are a strong predictor of hip fracture, and to a lesser extent humerus and ‘other’ limb fractures; however, they do not predict distal forearm fractures.

The Effects of Lifestyle, Dietary Dairy Intake and Diabetes on Bone Density and Vertebral Deformity Prevalence: The EVOS Study

Abstract. The risk of low and moderate energy fracture is related to bone mineral density (BMD). Yet it is uncertain whether the epidemiologic determinants of fracture risk are the same as for low bone density. The European Vertebral Osteoporosis Study was a population-based prevalence study of vertebral deformity in 36 age-stratified population samples aged 50–80 years. In nearly 4000 subjects (13 centers), BMD measurements were also made at the spine, femoral neck and femoral trochanter. To investigate whether effects of reported physical activity on spine deformity risk were mediated through BMD, we modeled these and other risk factor data with BMD as the dependent variate after adjusting for age, center, sex and body mass index (BMI). The significant determinants of vertebral deformity risk were also entered into logistic models of deformity risk that included BMD measurements as covariates. Both current and lifetime physical activity were positively associated with BMD. This effect was stronger with hip BMD than with spine BMD. Lifetime smoking exposure was associated with reduced BMD. Type 2 diabetes mellitus was associated with increased BMD. Weak positive associations were found between consumption of dairy products and BMD at the three measured sites and these were strengthened by an interaction with measures of physical activity in men. Physical activity in women had the largest beneficial effect in lean women and in women exposed to hormone replacement therapy. When fracture risk was modeled with BMD as a covariate, the lifestyle and dietary determinants became less strongly related to vertebral deformity risk, suggesting that BMD may have acted as an intermediary variable. However, heavy physical activity in men still increased spine deformity risk after adjusting for BMD. It is concluded that physical activity in both genders and milk consumption in young women might protect against vertebral deformities in later life through their effects on bone density. The adverse effect of smoking on BMD was confirmed. Heavy physical activity in men might increase spine deformity risk even when BMD is normal.

Forearm BMD as measured by peripheral quantitative computed tomography (pQCT) in a German reference population

Low bone mass as estimated by decreased bone mineral density (BMD) is an established predictor of osteoporotic fractures. One of the latest developments in bone densitometry is peripheral quantitative computed tomography (pQCT) of the forearm. In Germany, the CT bone scanner XCT 900 has already been widely used; however, interpretation of measurements with respect to osteoporosis risk assessment can be improved by better defined and validated reference data. In the present study, this device was used to measure BMD at the distal radius in a well-defined healthy population of 179 German adults (91 men, 88 women) aged 20–79 years. In vivo precision was 1.67% for trabecular and 0.81% for total BMD measurements. Peak values of trabecular and total BMD were observed at the ages 40–50 years in women and 30–40 years in men. Beyond these ages, both trabecular and total BMD showed a linear decline with age, decreasing by 0.85% and 1.08% per year in women and by 0.59% and 0.54% in men, respectively. Measures of BMD were not influenced by weight, height or body mass index (BMI). In both sexes, trabecular and total radial BMD showed a positive and significant correlation with femoral BMD measures obtained by dual X-ray absorptiometry (DXA). Weaker correlations were observed with DXA measures of the lumbar spine. Compared with the 95% reference range provided by the manufacturer, the distribution of age- and sex-specific values of trabecular BMD of the distal radius was shifted to lower values by up to 1 standard deviation. Thus, 17% (30 of 179) of our apparently healthy population had BMD values falling short of the suggested lower reference limit. On the other hand, the distribution of total BMD values was shifted to higher values by up to 2 standard deviations in the younger age groups. We conclude that pQCT of the radius is a precise method for measuring BMD, but that its use for osteoporosis risk assessment crucially depends on both well-defined reference data and the results of prospective studies.

Prevalence of Cardiovascular and Renal Complications in Older Adults With Normal or Impaired Glucose Tolerance or NIDDM: A population-based study

Objective— To determine the prevalence of CVD and renal disease by glucose tolerance status in a population-based study. Research Design and Methods— The study consisted of 991 men and 1243 women, aged 50-89 yr, living in the upper-middle class community of Rancho Bernardo, CA. All participants received a standard OGTT between 1984 and 1987. Results— A total of 159 men and 158 women had NIDDM, whereas 237 men and 348 women had IGT. Age-adjusted prevalence of complications generally was highest in those who were previously diagnosed with NIDDM. A significant correlation was observed between increases in the prevalence of complications and increases in glucose intolerance for microproteinuria, macroproteinuria, and myocardial infarction (borderline), as well as for stroke and claudication in men and myocardial infarction and stroke in women. In men with IGT or NIDDM, the age-adjusted prevalence of proteinuria and CVD was highest when other complications were present whereas in women such a prevalence was highest when other complications were absent. In men with diabetes, microproteinuria was associated with duration of disease. Conclusions— Prevalent CVD and renal disease were increased in adults with NIDDM and elevated in adults with IGT compared to those with normal glucose tolerance. The prevalence of complications in NIDDM subjects in this population-based study was substantially lower than that reported for clinic-based diabetic populations.