Partial misspecification of survey design features sufficed to severely bias estimates of health-related outcomes

Prevalence and risk factors of self-reported hearing loss, tinnitus, and dizziness in a population-based sample from rural northeastern Germany

A close anatomical and physiological relationship is known between the senses of hearing and balance, while an additional pathophysiological interaction is supposed. The mechanisms underlying this association are not yet fully understood, especially in individuals without a known specific otologic disorder. In particular, only scarce information on the combined occurrence of audiovestibular sensory impairment is available so far. Therefore, this study aims to provide further insight into the prevalence and co-prevalence of the audiovestibular symptoms hearing loss, tinnitus and dizziness. Additionally, the influence of potential risk factors from lifestyle habits as well as cardiovascular and metabolic conditions on the development of those symptoms is studied. Data was analyzed from 8134 individuals from the population-based Study of Health in Pomerania (SHIP). SHIP pursues a broad and comprehensive examination program in chronologically separated cohorts with longitudinal follow-up. Cohorts are sampled from Western Pomerania, a rural region of north-eastern Germany. The study population represents a cross-sectional analysis from the cohorts SHIP-START (recruited 1997-2001) and SHIP-TREND (recruited 2008-2012), sampled for baseline investigations (SHIP-START-0 and SHIP-TREND-0) at the age of 20-79 years. Audiovestibular symptoms as outcome variables were assessed by structured questionnaires. Additionally, individuals were comprehensively characterized regarding modifiable lifestyle factors as well as cardiovascular and metabolic disorders, allowing the assessment of their role as exposure variables. We calculated a weighted prevalence of 14.2% for hearing loss, 9.7% for tinnitus, and 13.5% for dizziness in the population. Prevalence increased with age and differed among the sexes. A considerable share of 28.0% of the investigated individuals reported more than one symptom at once. The prevalence of hearing loss as well as tinnitus increased between the two cohorts. A moderate positive correlation was found between the occurrence of hearing loss and tinnitus (phi-coefficient 0.318). In multivariable regression analyses, education was identified as a significant protective factor while only smoking was significantly associated with all three symptoms. Furthermore, several cardiovascular risk factors contributed to both hearing loss and dizziness. In conclusion, audiovestibular symptoms are highly prevalent in the investigated population. A considerable but complex influence of risk factors points towards a relation with neuronal as well as cardiovascular disease processes. To clarify the underlying mechanisms, the interaction between the senses of hearing and balance as well as the mode of action of the risk factors should be evaluated in more detail in the future.

Association of Lumbar MRI Findings with Current and Future Back Pain in a Population-based Cohort Study

STUDY DESIGN

Population-based cohort study.

OBJECTIVE

We examined associations between common lumbar degenerative changes observed on magnetic resonance imaging (MRI) and present or future low back pain (LBP).

SUMMARY OF BACKGROUND DATA

The association between lumbar MRI degenerative findings and LBP is unclear. Longitudinal studies are sparse.

METHODS

Participants (n = 3369) from a population-based cohort study were imaged at study entry, with LBP status measured at baseline and 6-year follow-up. MRI scans were reported on for the presence of a range of MRI findings. LBP status was measured on a 0 to 10 scale. Regression models were used to estimate the cross-sectional and longitudinal associations between individual and multiple MRI findings and LBP severity. Separate longitudinal analyses were conducted for participants with and without baseline pain.

RESULTS

MRI findings were present in persons with and without back pain at baseline. Higher proportions were found in older age groups. 76.4% of participants had a least one MRI finding and 8.3% had five or more different MRI findings. Cross-sectionally, most MRI findings were slightly more common in those with LBP and pain severity was slightly higher in those with MRI findings (ranging from 0.06 for high intensity zone to 0.83 for spondylolisthesis). In the longitudinal analyses, we found most MRI findings were not associated with future LBP-severity regardless of the presence or absence of baseline pain. Compared to zero MRI findings, having multiple MRI findings (five or more) was associated with mildly greater pain-severity at baseline (0.84; 0.50-1.17) and greater increase in pain-severity over 6 years in those pain free at baseline (1.21; 0.04-2.37), but not in those with baseline pain (-0.30; -0.99 to 0.38).

CONCLUSION

Our study shows that the MRI degenerative findings we examined, individually or in combination, do not have clinically important associations with LBP, with almost all effects less than one unit on a 0 to 10 pain scale.Level of Evidence: 3.

Effects of whole-body MRI on outpatient health service costs: a general-population prospective cohort study in Mecklenburg-Vorpommern, Germany

OBJECTIVE

Whole-body MRI (wb-MRI) is increasingly used in research and screening but little is known about the effects of incidental findings (IFs) on health service utilisation and costs. Such effects are particularly critical in an observational study. Our principal research question was therefore how participation in a wb-MRI examination with its resemblance to a population-based health screening is associated with outpatient service costs.

DESIGN

Prospective cohort study.

SETTING

General population Mecklenburg-Vorpommern, Germany.

PARTICIPANTS

Analyses included 5019 participants of the Study of Health in Pomerania with statutory health insurance data. 2969 took part in a wb-MRI examination in addition to a clinical examination programme that was administered to all participants. MRI non-participants served as a quasi-experimental control group with propensity score weighting to account for baseline differences.

PRIMARY AND SECONDARY OUTCOME MEASURES

Outpatient costs (total healthcare usage, primary care, specialist care, laboratory tests, imaging) during 24 months after the examination were retrieved from claims data. Two-part models were used to compute treatment effects.

RESULTS

In total, 1366 potentially relevant IFs were disclosed to 948 MRI participants (32% of all participants); most concerned masses and lesions (769 participants, 81%). Costs for outpatient care during the 2-year observation period amounted to an average of €2547 (95% CI 2424 to 2671) for MRI non-participants and to €2839 (95% CI 2741 to 2936) for MRI participants, indicating an increase of €295 (95% CI 134 to 456) per participant which corresponds to 11.6% (95% CI 5.2% to 17.9%). The cost increase was sustained rather than being a short-term spike. Imaging and specialist care related costs were the main contributors to the increase in costs.

CONCLUSIONS

Communicated findings from population-based wb-MRI substantially impacted health service utilisation and costs. This introduced bias into the natural course of healthcare utilisation and should be taken care for in any longitudinal analyses.

The effects of incidental findings from whole-body MRI on the frequency of biopsies and detected malignancies or benign conditions in a general population cohort study

Magnetic resonance imaging (MRI) yields numerous tumor-related incidental findings (IFs) which may trigger diagnostics such as biopsies. To clarify these effects, we studied how whole-body MRI IF disclosure in a population-based cohort affected biopsy frequency and the detection of malignancies. Laboratory disclosures were also assessed. Data from 6753 participants in the Study of Health in Pomerania (SHIP) examined between 2008 and 2012 were utilized. All underwent laboratory examinations and 3371 (49.9%) a whole-body MRI. Electronic biopsy reports from 2002 to 2017 were linked to participants and assigned to outcome categories. Biopsy frequency 2 years pre- and post-SHIP was investigated using generalized estimating equations with a negative-binomial distribution. Overall 8208 IFs (laboratory findings outside reference limits: 6839; MRI: 1369) were disclosed to 4707 participants; 2271 biopsy reports belonged to 1200 participants (17.8%). Of these, 938 biopsies occurred pre-SHIP; 1333 post-SHIP (event rate/100 observation years = 6.9 [95% CI 6.5; 7.4]; 9.9 [9.3; 10.4]). Age, cancer history, recent hospitalization, female sex, and IF disclosure were associated with higher biopsy rates. Nonmalignant biopsy results increased more in participants with disclosures (post-/pre-SHIP rate ratio 1.39 [95% CI 1.22; 1.58]) than without (1.09 [95% CI 0.85; 1.38]). Malignant biopsy results were more frequent post-SHIP (rate ratio 1.74 [95% CI 1.27; 2.42]). Biopsies increased after participation in a population-based cohort study with MRI and laboratory IF disclosure. Most biopsies resulted in no findings and few malignancies were diagnosed, indicating potential overtesting and overdiagnosis. A more restrictive policy regarding IF disclosure from research findings is required.

Prevalence of benign osseous lesions of the spine and association with spinal pain in the general population in whole body MRI

Background

Benign osseous lesions of the spine are common but precise population prevalence estimates are lacking. Our study aimed to provide the first population-based prevalence estimates and examine association with back and neck pain.

Materials and methods

We used data from the population-based Study of Health in Pomerania (SHIP). Whole-body MRI examinations (1.5 Tesla: T1, T2, and TIRM weightings) were available from 3,259 participants. Readings of the spinal MRI images were conducted according to a standardized protocol by a single reader (JS). The intra-rater reliability was greater than Kappa values of 0.98. Pain measures included the seven-day prevalence of spine pain and neck pain, and average spine pain intensity due to spine pain during the past three months.

Results

We found 1,200 (36.8%) participants with at least one osseous lesion (2,080 lesions in total). Osseous lesions were less common in men than in women (35.5% vs 38.9%; P = .06). The prevalence of osseous lesions was highest at L2 in both sexes. The prevalence of osseous lesions increased with age. Up to eight osseous lesions were observed in a single subject. Hemangioma (28%), and lipoma (13%) occurred most often. Sclerosis (1.7%), aneurysmal bone cysts (0.7%), and blastoma (0.3%) were rare. Different osseous lesions occurred more often in combination with each other. The association with back or neck pain was mostly negligible.

Conclusion

Osseous lesions are common in the general population but of no clinical relevance for spinal pain. The prevalence of osseous lesions varied strongly across different regions of the spine and was also associated with age and gender. Our population-based data offer new insights and assist in judging the relevance of osseous lesions observed on MRIs of patients.

Irritable bowel syndrome, mental health, and quality of life: Data from a population-based survey in Germany (SHIP-Trend-0)

BACKGROUND

Irritable bowel syndrome (IBS) is associated with reduced quality of life and high healthcare costs. This study aimed to assess the prevalence and risk factors for IBS in a general adult population.

METHODS

The Study of Health in Pomerania (SHIP) is a population-based cohort study in northeastern Germany. SHIP-Trend-0 participants enrolled from 2008 to 2012 were grouped according to Rome III criteria (main criteria: abdominal discomfort or crampy or bloating pain for at least six months plus 2/3 additional criteria). Factors associated with IBS were assessed using survey-weighted backward stepwise logistic regression.

KEY RESULTS

The final data set included 4194 records. IBS prevalence was 3.5% (3.0%-4.2%). Unemployment (OR: 2.02, 1.26-3.21), headaches (OR: 2.37, 1.59-3.52), mental quality of life (OR: 0.95 per unit increase, 0.93-0.97), and interactions between gender and physical quality of life (P = 0.004) and gender and alexithymia (P = 0.002) predicted IBS probability. The model resulted in a good discrimination (area under the curve = 75.4%) and model fit (F = 0.72, P = 0.69). History of depression (OR: 2.77, 1.94-3.95), back pain (OR: 2.38, 1.69-3.35), early trauma (OR: 1.03, 1.02-1.04), and duration of inpatient treatment within the last twelve months (OR: 1.02, 1.01-1.04) lost their significance in multivariable analysis.

CONCLUSIONS & INFERENCES

IBS prevalence was relatively low compared to other studies. Factors predicting IBS were of biological, psychological, and social nature. The association between IBS and pain in different areas of the body indicates a potential underlying complex somatic symptom disorder.

What Are the Reference Values and Associated Factors for Center-edge Angle and Alpha Angle? A Population-based Study

BACKGROUND

The available evidence regarding normal ranges for the center-edge angle and the alpha angle derives from a few small studies, and associated factors such as sex and anthropometric factors have not been well evaluated. Knowing more about normal values for these parameters is critical, because this can inform decisions about when to perform elective hip preservation surgery. Population-level studies would provide considerable clarity on these issues, but to our knowledge, no such studies are available.

QUESTIONS/PURPOSES

The purposes of this study were (1) to use MRI in patients of a population-based study to establish normal values for the alpha and center-edge angles in the normal adult hip; and (2) to determine whether age, sex, or anthropometric variables were associated with differences in these values.

METHODS

We used MRI images (1.5 T) of 3226 participants of the Study of Health in Pomerania (SHIP). SHIP is a population-based study that started with 4308 participants in 1997. Participants were recruited randomly from official inhabitant data files as a stratified cluster sample of the population from a defined region in northeastern Germany. To ensure a representative epidemiologic cohort, stratification variables were sex, age, and city of residence. Between 2008 and 2012, 1094 of these participants underwent whole-body MRI with pelvic sequences in the second followup. In parallel, the next cohort, SHIP-Trend, started with the same protocol in which 2132 participants underwent MRI examination. Reference values were calculated by quantile regressions for the 2.5 and 97.5 percentiles. Associations with the demographic features sex, age, weight, height, body mass index (BMI), and waist circumference were analyzed by bivariate linear regression models.

RESULTS

The mean center-edge angle was 31° (± 7°) with a corresponding calculated normal range of 17° to 45°. The mean alpha angle was 55° (± 8°) with a corresponding calculated normal range between 39° and 71°. Men (30° ± 7°) had a lower center-edge angle than women (32° ± 8°) (p < 0.001, β = 1.4°; 95% confidence interval [CI], 0.9°-1.9°) and a higher alpha angle (57° ± 8° versus 52° ± 7°, p < 0.001, β = 5.7°; 95% CI, 5.2°-6.3°). Moreover, a higher center-edge angle for the left side was found (33° ± 8° versus 30° ± 8°, p < 0.001, β =3.2°; 95% CI, 3.0°-3.4°). In addition to sex, we found that age, height, waist circumference, and BMI affected both center-edge angle and alpha angle. Weight was associated with the alpha angle as well. Because of these associations, age- and sex-adjusted reference values with belonging formulas were calculated.

CONCLUSIONS

The range of normal center-edge and alpha angles is quite wide. Therefore, only markedly abnormal angles may be associated with pathology. Moreover, center-edge angle and alpha angle are associated with age, sex, and anthropometric factors, which have to be taken into account for better interpretation.

CLINICAL RELEVANCE

The association of abnormal radiographic values with true clinical hip pathology is tenuous at best. Assuming that a patient with an abnormal radiograph requires treatment is unwise. The clinical picture has to be substantial for therapeutic decisions.

Is hepatic steatosis associated with left ventricular mass index increase in the general population?

AIM

To investigate the association between hepatic steatosis and change in left ventricular mass index (LVMI) over five years, and examine whether systolic and diastolic blood pressures are mediators of the association between hepatic steatosis and LVMI using a general population sample.

METHODS

We analyzed data from the Study of Health in Pomerania. The study population comprised 1298 individuals aged 45 to 81 years. Hepatic steatosis was defined as the presence of a hyperechogenic pattern of the liver together with elevated serum alanine transferase levels. Left ventricular mass was determined echocardiographically and indexed to height^2.7. Path analyses were conducted to differentiate direct and indirect paths from hepatic steatosis to LVMI encompassing systolic and diastolic blood pressure as potential mediating variables.

RESULTS

Hepatic steatosis was a significant predictor for all measured echocardiographic characteristics at baseline. Path analyses revealed that the association of hepatic steatosis with LVMI change after five years was negligibly small (β = -0.12, s.e. = 0.21, P = 0.55). Systolic blood pressure at baseline was inversely associated with LVMI change (β = -0.09, s.e. = 0.03, P < 0.01), while no association between diastolic blood pressure at baseline and LVMI change was evident (β = 0.03, s.e. = 0.05, P = 0.56). The effect of the indirect path from hepatic steatosis to LVMI via systolic baseline blood pressure was small (β = -0.20, s.e. = 0.10, P = 0.07). No indirect effect was observed for the path via diastolic baseline blood pressure (β = 0.03, s.e. = 0.06, P = 0.60). Similar associations were observed in the subgroup of individuals not receiving beta-blockers, calcium channel blockers, or drugs acting on the renin-angiotensin system.

CONCLUSION

Baseline associations between hepatic steatosis and LVMI do not extend to associations with LVMI change after five years. More studies are needed to study the longitudinal effects of hepatic steatosis on LVMI.

Association of PNPLA3 rs738409 and TM6SF2 rs58542926 with health services utilization in a population-based study

Background

Hepatic steatosis confers an increased risk of metabolic and cardiovascular disease and higher health services use. Associations of the single nucleotide polymorphisms (SNP) PNPLA3 rs738409 and TM6SF2 rs58542926 with hepatic steatosis have recently been established. This study investigates the association between rs738409 and rs58542926 with health services utilization in a general population.

Methods

Data of 3759 participants from Study of Health in Pomerania (SHIP), a population-based study in Germany, were obtained. The annual number of outpatient visits, hospitalization and length of hospital stay was regressed on rs738409 and rs58542926 and adjusted for socio-economic factors, lifestyle habits, clinical factors, and health status.

Results

Minor allele homozygous subjects of rs738409 had an increased odds of hospitalization as compared to major allele homozygous subjects (odds ratio [OR] 1.51; 95 % confidence interval [CI], 1.02 to 2.15). Heterozygous subjects did not differ from major allele homozygous subjects with respect to their odds of hospitalization. The three genotype groups of rs738409 were similar with respect to the number of outpatient visits and inpatient days. Minor allele homozygous and heterozygous subjects of rs58542926 had higher outpatient utilization (+53.04 % and +67.56 %, p < 0.05, respectively) and inpatient days than major allele homozygous subjects.

Conclusions

After adjustment for several confounding factors, PNPLA3 rs738409 and TM6SF2 rs58542926 were associated with the number of outpatient visits, hospitalization, and inpatient days. Further studies are warranted to replicate our findings and to evaluate whether genetic data can be used to identify subjects with excess health services utilization.

Prevalence trends in lifestyle-related risk factors

BACKGROUND

The regional prevalence of risk factors can vary over time. The Study of Health in Pomerania (SHIP) addresses prevalence trends for common risk factors in a region in northeast Germany.

METHODS

A longitudinal study was carried out from 1997 to 2001 (SHIP-0, with 4308 subjects), and a second, independent random sample of the population in the same region was studied from 2008 to 2012 (SHIP-Trend, with 4420 subjects). All data were standardized with post-stratification weighting derived from the adult population of the state of Mecklenburg-West Pomerania.

RESULTS

SHIP reveals a marked decline of mean alcohol consumption in the adult population, from 5.57 g/day (95% confidence interval, 5.51-5.63) to 3.12 g/day (95% CI 3.09-3.15). The percentage of active smokers among men declined from 38.6% (95% CI 36.0-41.2) to 34.3% (95% CI 32.1-36.6). Simultaneously, however, there was a rightward shift of the BMI distribution, with a marked increase in the prevalence of obesity, from 24.7% to 32.0%. There was a corresponding increase in the prevalence of diabetes, from 9.1% to 13.8%. Compared to eleven years ago, the amount of exercise taken during free time has risen among the elderly, but fallen among young women.

CONCLUSION

Tobacco and alcohol consumption have declined over the past decade, although this study may have overestimated these trends through a combination of selection bias and reporting bias. Meanwhile, the northeast German population now has a worse metabolic risk profile, as indicated by the increased prevalence of obesity and diabetes. Society as a whole must take measures to combat this trend.

Changes in prevalence of periodontitis in two German population-based studies

AIM

We aimed to assess changes of periodontal status in Germany.

MATERIALS & METHODS

The Studies of Health in Pomerania (SHIP) are two cross-sectional population-based studies conducted during 1997-2001 (SHIP-0, 20-81 years, n = 3736) and 2008-2012 (SHIP-Trend, 20-84 years, n = 3622) in northeast Germany. The German Oral Health Studies (DMS, 35-44 and 65-74 years) are national cross-sectional population-based surveys conducted in 1997 (DMS III, n = 1454) and 2005 (DMS IV, n = 1668), whose results were separately reported for West and East Germany. Prevalences, percentages and numbers of teeth affected were defined.

RESULTS

In SHIP, prevalence of attachment loss (AL) ≥ 3 mm decreased from 89.7% (95% confidence interval (CI): 88.6-90.8) to 85.1% (95%CI: 83.9-86.3) (p < 0.05) and the mean extent reduced from 62.8% (95%CI: 61.7-63.8) to 55.9% (95%CI: 54.9-56.9) (p < 0.05). Probing depth (PD) ≥ 4 mm and the respective extent remained unchanged. In West Germany, AL ≥ 3 mm decreased for 35-44-year-olds and increased for 65-74-year-olds (p < 0.05). In SHIP and DMS, the number of teeth in dentates increased significantly in all age groups.

CONCLUSIONS

Prevalences and extents of AL improved almost in all age categories in SHIP and West German adults, whereas PDs remained unchanged. Nonetheless, the improvement of periodontal conditions implies an increase of treatment needs regarding moderately diseased teeth because of simultaneous increases of the number of present teeth.

Psychometric functioning, socio-demographic variability of childhood maltreatment in the general population and its effects of depression

Maltreatment of children is a major public-health and social-welfare problem but socio-demographic variability has received little attention. This work addresses such variability in a general population cohort and associations with depression. Analyses were based on the cross-sectional SHIP-LEGEND examination among 2265 adults (29-89 years). Childhood maltreatment was multi-dimensionally assessed with the German 28-item Childhood Trauma Questionnaire (CTQ): emotional neglect; emotional abuse; physical neglect; physical abuse; sexual abuse. Non-linear associations between CTQ responses and age were assessed with fractional polynomials and cubic splines. Scale properties were analysed with confirmatory factor analyses and item response models. Associations between childhood maltreatment domains and depression [Beck Depression Inventory-II (BDI-II)] were assessed. The majority (58.9%) reported events indicative of at least mild levels of childhood maltreatment. CTQ subscales showed characteristically different non-linear associations to age across the five studied domains, indicating methodological issues like recall bias and the influence of seminal events. Psychometric scale properties were acceptable to good for all subscales except for physical neglect. Associations to depression measures varied systematically across socio-demographic strata. We conclude that socio-demographic variability is a major issue when studying self-reported childhood maltreatment in a community sample. This needs to be taken into account for the study of associations to psychiatric key outcomes.

The impact of childhood trauma on depression: does resilience matter? Population-based results from the Study of Health in Pomerania

OBJECTIVE

Data suggests that traumatic experiences at early age contribute to the onset of major depressive disorder (MDD) in later life. This study aims at investigating the influence of dispositional resilience on this relationship.

METHODS

Two thousand and forty-six subjects aged 29-89 (SD=13.9) from a community based sample who were free of MDD during the last 12 months prior to data collection were diagnosed for Lifetime diagnosis of MDD by the Munich-Composite International Diagnostic Interview (M-CIDI) according to DSM-IV criteria. Childhood maltreatment (CM) and resilience were assessed with the Childhood Trauma Questionnaire (CTQ) and the Resilience-Scale (RS-25).

RESULTS

Both CM (OR=1.03, 95% CI [1.02, 1.04], P<.000) and resilience (OR=0.98, 95% CI [0.98, 0.99], P<.000) were associated with MDD later in life. The detrimental effects of low resilience on MDD were not only especially prominent in subjects with a history of CM (OR=3.18, 95% CI [1.84, 5.50], P<.000), but also effective in subjects without CM (OR=2.62, 95% CI [1.41, 4.88], P=.002).

CONCLUSIONS

The findings support the clinical assumption that resilient subjects may be partly protected against the detrimental long-term effects of child abuse and neglect.

Association of natural anti-platelet factor 4/heparin antibodies with periodontal disease

Platelet factor 4 (PF4) and heparin (H) form PF4/H complexes, the target of the immune reaction in heparin-induced thrombocytopenia (HIT). HIT seems to be a secondary immune response as anti-PF4/H-IgG antibodies occur as early as day 4 of heparin treatment. This study investigated whether prevalent infections such as periodontitis may induce the PF4/H immune response as: (1) natural anti-PF4/H Abs are present in the normal population; (2) PF4 bound to bacteria exposes the same antigen(s) as PF4/H complexes; and (3) sepsis induces PF4/H Abs in mice. We found PF4 bound to periodontal pathogens (Aggregatibacter actinomycetemcomitans; Porphyromonas gingivalis) enabling subsequent binding of human anti-PF4/H Abs. The association of natural PF4/H Abs and periodontitis was assessed in a case-control study, enrolling individuals with natural anti-PF4/H Abs (n = 40 matched pairs), and in the cross-sectional population-based Study of Health in Pomerania (SHIP; n = 3500). Both studies showed a robust association between periodontitis and presence of anti-PF4/H Abs independent of inflammation markers (case-control study: lowest vs highest tertile, odds ratio, 7.12 [95% confidence interval, 1.73-46.13; P = .005]; SHIP study, p(trend) ≤ 0.001). Thus, preimmunization to PF4/bacteria complexes by prevalent infections, for example, periodontitis, likely explains the presence of natural anti-PF4/heparin Abs and the early occurrence of anti-PF4/H-IgG in HIT.