Breast cancer survival in Ethiopia: a cohort study of 1,070 women

There is little information on breast cancer (BC) survival in Ethiopia and other parts of sub-Saharan Africa. Our study estimated cumulative probabilities of distant metastasis-free survival (MFS) in patients at Addis Ababa (AA) University Radiotherapy Center, the only public oncologic institution in Ethiopia. We analyzed 1,070 females with BC stage 1-3 seen in 2005-2010. Patients underwent regular follow-up; estrogen receptor-positive and -unknown patients received free endocrine treatment (an independent project funded by AstraZeneca Ltd. and facilitated by the Axios Foundation). The primary endpoint was distant metastasis. Sensitivity analysis (worst-case scenario) assumed that patients with incomplete follow-up had events 3 months after the last appointment. The median age was 43.0 (20-88) years. The median tumor size was 4.96 cm [standard deviation (SD) 2.81 cm; n = 709 information available]. Stages 1, 2 and 3 represented 4, 25 and 71%, respectively (n = 644). Ductal carcinoma predominated (79.2%, n = 1,070) as well as grade 2 tumors (57%, n = 509). Median follow-up was 23.1 (0-65.6) months, during which 285 women developed metastases. MFS after 2 years was 74% (69-79%), declining to 59% (53-64%) in the worst-case scenario. Patients with early stage (1-2) showed better MFS than patients with stage 3 (85 and 66%, respectively). The 5-year MFS was 72% for stages 1 and 2 and 33% for stage 3. We present a first overview on MFS in a large cohort of female BC patients (1,070 patients) from sub-Saharan Africa. Young age and advanced stage were associated with poor outcome.

From embouchure problems to embouchure dystonia? A survey of self-reported embouchure disorders in 585 professional orchestra brass players

OBJECTIVES

Data concerning embouchure problems in professional brass players are scarce. Embouchure problems can potentially lead to focal dystonia. The aim of this study was to investigate the frequency of distinct embouchure problems in professional brass players. Furthermore, the frequency of "cramping", a distinct symptom of embouchure dystonia, was evaluated in the context of established embouchure dystonia risk factors.

METHODS

Five hundred and eighty-five professional brass players participated in a cross-sectional study concerning embouchure problems. A self-administered questionnaire was developed to evaluate embouchure fatigue, embouchure disorders and their consequences. To study the association between risk factors and cramping (a symptom of embouchure dystonia), a log-binomial regression analysis was conducted, enabling estimation of prevalence ratios (PR) and 95 % confidence intervals (95 % CI).

RESULTS

Thirty percent (95 % CI 25.9-33.3) reported embouchure fatigue. The relative frequency of embouchure disorders was 59 % (95 % CI 54.6-63.6), with 26 % (95 % CI 22.4-29.5) reporting embouchure cramping. Embouchure disorders resulted in sick leave in 16 % (95 % CI 12.7-20.6). Female brass players (PR 2.0, 95 % CI 0.98-3.98) and musicians with a prior change in their embouchure (PR 2.4, 95 % CI 1.38-4.05) or breathing technique (PR 2.2, 95 % CI 1.25-3.72) and musicians with embouchure fatigue (PR 1.9, 95 % CI 1.18-2.93) presented more frequently with embouchure cramping than musicians with other or without risk factors.

CONCLUSION

This study shows a high relative frequency of embouchure problems in professional brass players. Given that embouchure dystonia is often preceded by embouchure problems, these findings may assist in gaining further insight into the characteristics of embouchure dystonia and the development of preventive strategies.

Treatment of aneurysmal subarachnoid haemorrhage in Germany: a nationwide analysis of the years 2005-2009

BACKGROUND

The aim of this study was to provide population-based nationwide rates of the different treatment modalities of aneurysmal subarachnoid haemorrhage (aSAH).

METHODS

German Diagnosis-Related Group data of the years 2005-2009 were used to calculate hospitalisation rates for intracranial aneurysm with aSAH. This study includes over 83 million hospitalisations.

RESULTS

We identified 15,768 hospitalisations with a diagnosis of aSAH. Throughout the observation period, the age-standardised rate for both sexes increased by 69% (95% confidence interval, CI 54-84) for coiling and 13% (95% CI 4-23) for clipping. The estimated annual percent change in the overall hospitalisation rate was 7.4% (95% CI 5.2-9.6). Age-standardised hospitalisation rates varied considerably by region. The estimated hospitalisation rate ratio of overall hospitalisation rates (East/West) was 0.86 (95% CI 0.80-0.91) for males and 0.81 (95% CI 0.77-0.85) for females. After adjustment for age and co-morbidity, the hazard ratio (HR) for in-hospital mortality was higher for coiling than clipping (HR = 1.12, 95% CI 1.01-1.23). Patients who received coiling or clipping had ventricular shunt placement in 5.0 (n = 819) and 6.1% (n = 998), respectively. The estimated length of stay was 3.3 days (95% CI 2.56-4.05) shorter for coiling than clipping.

CONCLUSIONS

We provide for the first time nationwide, representative hospitalisation rates for the treatment of aSAH. Our results indicate a change in the practice pattern for Germany during the observation period. We observed a gradual increase in overall hospitalisation rates for aSAH.

Effect of smoking and other traditional risk factors on the onset of coronary artery calcification: results of the Heinz Nixdorf recall study

BACKGROUND

Coronary artery calcium (CAC) indicates coronary atherosclerosis and can be present in very early stages of the disease. The conversion from no CAC to any CAC reflects an important step of the disease process as cardiovascular risk is increased in persons even with mildly elevated CAC. We sought to identify risk factors that determined incident CAC>0 in men and women from an unselected general population with a special focus on the role of smoking.

METHODS

All 4814 persons that were initially studied in the Heinz Nixdorf Recall Study were invited to participate in the follow-up examination after 5.1 ± 0.3 years. All traditional Framingham risk factors were quantified using standard techniques. Smokers were categorized in never, former and present smokers. The CAC scores were measured from EBCT using the Agatston method.

RESULTS

Overall, out of 342 men and 919 women with zero CAC at baseline, 107 (31.3%) men and 210 (22.9%) women had CAC>0 at second examination. In multivariable analysis, age (OR estimate per 5 years: 1.34 (95%CI: 1.21-1.47)), LDL cholesterol (per 10 mg/dL: 1.05 (95%CI: 1.01-1.10)), systolic blood pressure (per 10 mmHg: 1.19 (95%CI: 1.11-1.28)) and current smoking (1.49 (95%CI: 1.04-2.15)) were independent predictors of CAC onset. The probability of CAC onset steadily increased with age from 23.3% (men) and 15.3% (women) at age 45-49 years to 66.7% (men) and 42.9% (women) at age 70-74 years. The difference in age-dependent conversion rates was quantified by years between reaching a given level of CAC onset probability. We found a consistent pattern with respect to smoking status: presently (formerly) smoking middle-aged men convert to positive CAC 10 (5) years earlier than never smokers, for women (middle-aged to elderly) this time span is 8 (5) years.

CONCLUSION

Several traditional CVD risk factors are associated with CAC onset during 5 years follow-up. CAC onset is accelerated by approximately 10 (5) years for present (former) compared to never smokers.

Association of obstructive sleep apnoea with subclinical coronary atherosclerosis

BACKGROUND

Accumulating evidence suggests a role of obstructive sleep apnoea (OSA) as a risk factor for coronary atherosclerosis. This study aimed i) to assess the prevalence of OSA in the general population and ii) to analyse the association of this disorder with traditional cardiovascular disease risk factors and subclinical coronary atherosclerosis.

METHODS

In a cross-sectional analysis of the Heinz Nixdorf Recall study a subgroup of 1604 subjects (791 men, age 50-80 years) underwent OSA screening. Furthermore, coronary artery calcium (CAC) was measured. OSA was defined as apnoea-hypopnoea index (AHI) ≥ 15/h.

RESULTS

OSA was observed in 29.1% of men and 15.6% of women. In a multiple linear regression analysis adjusted for risk factors AHI was associated with CAC in men aged ≤65 years (estimated log-transformed increase of CAC = 0.25, 95% confidence interval (CI) = -0.001-0.50, p = 0.051) and in women of any age (estimated log-transformed increase = 0.23, 95% CI = 0.04-0.41, p = 0.02). Doubling of the AHI was associated with a 19% increase of CAC in men aged ≤65 years and with a 17% increase in women of any age.

CONCLUSIONS

In the general population aged ≥50 years OSA is associated with subclinical atherosclerosis in men aged ≤65 years and in women of any age, independent of traditional cardiovascular risk factors.

A population-based case-control study on social factors and risk of testicular germ cell tumours

OBJECTIVES

Incidence rates for testicular cancer have risen over the last few decades. Findings of an association between the risk of testicular cancer and social factors are controversial. The association of testicular cancer and different indicators of social factors were examined in this study.

DESIGN

Case-control study.

SETTING

Population-based multicentre study in four German regions (city states Bremen and Hamburg, the Saarland region and the city of Essen).

PARTICIPANTS

The study included 797 control participants and 266 participants newly diagnosed with testicular cancer of which 167 cases were classified as seminoma and 99 as non-seminoma. The age of study participants ranged from 15 to 69 years.

METHODS

Social position was classified by educational attainment level, posteducational training, occupational sectors according to Erikson-Goldthorpe-Portocarrero (EGP) and the socioeconomic status (SES) on the basis of the International SocioEconomic Index of occupational status (ISEI). ORs and corresponding 95% CIs (95% CIs) were calculated for the whole study sample and for seminoma and non-seminoma separately.

RESULTS

Testicular cancer risk was modestly increased among participants with an apprenticeship (OR=1.7 (95% CI 1.0 to 2.8)) or a university degree (OR=1.6 (95% CI 0.9 to 2.8)) relative to those whose education was limited to school. Analysis of occupational sectors revealed an excess risk for farmers and farm-related occupations. No clear trend was observed for the analyses according to the ISEI-scale.

CONCLUSIONS

Social factors based on occupational measures were not a risk factor for testicular cancer in this study. The elevated risk in farmers and farm-related occupations warrants further research including analysis of occupational exposures.

Gender-specific association of coronary artery calcium and lipoprotein parameters: the Heinz Nixdorf Recall Study

BACKGROUND

Coronary atherosclerosis can be detected by computed tomography. The amount of coronary artery calcification (CAC) is related to cardiovascular risk factors, the strength of the gender specific relation between lipoprotein parameters and CAC has not extensively been studied. Especially, the role of routinely determined lipoproteins in contrast to less common and computed lipid parameters (e.g. ratios) remains to be clarified.

METHODS AND RESULTS

The study cohort (n = 3956, 52% women, age 45-75 years) was randomly selected from three cities of a German metropolitan area. Lipoproteins-low-and high density lipoprotein (LDL-C/HDL-C), total cholesterol, apolipoprotein A-1 and B (apoA-1/apoB) as well as lipoprotein (a) (Lp(a)) were measured, while non-HDL-C was calculated. All participants received an electron-beam computed tomography (EBCT) for quantification of CAC. Adjusted for age and cardiovascular risk factors, CAC increased by a factor of 1.97 (1.51-2.57, 95% CI) and 1.94 (1.53-2.45, 95% CI) comparing the fourth to the first quartile of LDL-C for men and women, respectively. This association with LDL-C was also found after dichotomization of CAC at thresholds >0, ≥ 100 and ≥ 400. The best association of CAC was, however, found to be apoB and the second best was non HDL-C, in both men and women. For apoB, the model including all risk factors reached an explained variance for CAC of 20.2% in men and of 21.6% in women. When using LDL-C as a given parameter according to the current practice and advice, HDL-C in men and apoB in women provided an additional but small benefit.

CONCLUSION

ApoB showed the best association with CAC compared to all other tested lipoproteins. Neither the ratio LDL-C/HDL-C nor apoB/apoA-1, or Lp(a) revealed a closer association with CAC. While lipoproteins are related to CAC more closely in women than in men, their association with CAC is, however, not particularly strong. Our results may influence primary and secondary prevention advices in order to improve detection of subclinical atherosclerosis, for which lipoprotein parameters can only play a minor role.

Impact of atherosclerotic risk factors on different ankle-brachial-index criteria--results of the Heinz Nixdorf RECALL study

BACKGROUND

On the basis of the Heinz Nixdorf RECALL Study (HNR) we estimated the impact of classical atherosclerotic risk factors on different ankle-brachial-index (ABI) criteria.

PATIENTS AND METHODS

In a subgroup of participants (n = 2586) who had normal ABI at baseline ABI measurement was repeated at a 5 years follow-up and 3 different ABIs were defined: "ABI-high" calculated from the higher pressure, "ABI-low" from the lower pressure of both foot arteries of each leg. "Pure-ABI-low" was defined by exclusion of participants with ABI-high from those with ABI-low. Mönckebergs mediacalcinosis (MC) was accepted in case of ABI-high > 1.4 in one leg.

RESULTS

According to ABI-high 2 %, to ABI-low 7.8 % and pure-ABI-low 5.8 % of the participants developed peripheral arterial disease (PAD) (ABI < 0.9) and 3.6 % developed MC within the 5 years. Age did not play any role whereas female gender, diabetes mellitus and smoking were associated with an increased relative risk of pathologic ABI-high and ABI-low. Looking at the pure-ABI-low group only, female gender and smoking showed significant associations. None of the analysed risk factors except gender had an impact on the development of MC.

CONCLUSIONS

Classical risk factors have different impact on incidence of PAD as defined by different ABI criteria.

Survival after a diagnosis of testicular germ cell cancers in Germany and the United States, 2002-2006: a high resolution study by histology and age

INTRODUCTION

The aim of this study was to provide detailed age-specific (5-year age groups) and histology-specific (histologic subtypes of seminoma and nonseminoma) relative survival estimates of testicular germ cell cancer patients in Germany and the United States (U.S.) for the years 2002-2006 and to compare these estimates between countries.

METHODS

We pooled data from 11 cancer registries of Germany and used data from the U.S. (SEER-13 database) including 11,508 and 10,774 newly diagnosed cases (1997-2006) in Germany and the U.S., respectively. We estimated 5-year relative survival (5-year-RS) by histology and age based on period analysis.

RESULTS

5-year-RS for testicular germ cell tumors was 96.7% and 96.3% in Germany and the U.S., respectively. 5-Year-RS for spermatocytic seminoma was close to 100% in both countries. 5-Year-RS for nonseminoma was lower than for classical seminoma in Germany (93.3% versus 97.6%) and the U.S. (91.0% versus 98.2%). Among nonseminomas, choriocarcinomas provided the lowest 5-year-RS in both countries (Germany 80.1%, U.S. 79.6%). Age-specific 5-year-RS for seminoma showed only little variation by age. 5-Year-RS for nonseminomas tended to be lower at higher ages, especially for malignant teratoma.

DISCUSSION

This is the first study that provides up-to-date survival estimates for testicular cancer by histology and age in Germany and the U.S. Survival after a diagnosis of testicular cancer is very comparable between Germany and the U.S. 5-Year-RS for spermatocytic seminoma was close to 100% and the lowest 5-year-RS occurred among choriocarcinoma. Higher age at diagnosis is associated with a poorer prognosis among nonseminoma patients.

Population-based incidences of non-fatal injuries - results of the German-wide telephone survey 2004

Background

To plan preventive measures against accident-related injuries, it is important to have detailed epidemiological data on this topic. The aim of this report was to present population-based incidence estimates of injuries due to non-fatal accidents in relation to age, gender and educational level.

Methods

We performed a cross-sectional telephone survey from 2003 to 2004 of the resident adult population of Germany, which included 7,341 subjects (response rate: 32.6 to 39.4%). The interview included 13 questions about injuries caused by accidents that happened in the 12 months preceding the interview. We estimated one-year cumulative incidences of injuries by gender, age and educational level.

Results

Overall, 10.3% of the subjects reported an unintentional injury requiring medical treatment in the previous 12 months. The age-standardised incidence of injuries was higher among men than women (men: 11.3%, women: 8.9%). Generally, accidents at home were the most frequently reported (27.4%). Men and women aged 18 to 29 years suffered accident-related injuries (and also repeated injuries) the most often during the preceding 12 months.

Although the overall incidence of injuries caused by accidents did not differ by educational level, the incidences of accidents at different places differed by educational level. The incidence of work-related injuries was higher among people with a low educational level.

Conclusions

Our age- and gender-specific results provide detailed insight into specific patterns of accident-related injuries in Germany. Young men are especially at high risk of injuries. This information is valuable because a nationwide comprehensive recording of injuries caused by accidents does not exist. The data highlight the target groups for injury prevention measures.

Frequency of computed tomography examinations in the follow-up care of testicular cancer patients - an evaluation of patterns of care in Germany

BACKGROUND

Exposure to radiation resulting from diagnostic imaging procedures probably increases late cancer risk. Patterns of care regarding the application of computed tomography (CT) imaging in testicular cancer patients were investigated.

METHODS

The database of a large German health insurance company comprising 850,000 insured men was searched for cases of testicular cancer arising in the years 2005 and 2006. The number of CT scans applied during a 3-year period of follow-up was noted for each individual patient and the resulting cumulative radiation dose was estimated. The number of CT scans actually observed was compared to guideline recommendations.

RESULTS

177 patients were identified. Within the 3-year observation period, patients received a mean of 4.4 CT scans (standard error: 0.4) whereas a number of 6.2 would have been expected according to contemporary guidelines. Patients were exposed to an estimated total median diagnostic radiation dose of 30 millisieverts (mSv) (interquartile range: 10-54 mSv).

CONCLUSION

There is a considerable gap between recommendation and actual performance regarding the number of CT scans applied to testicular cancer patients. Unfamiliarity of clinicians with guidelines as well as poor acceptance of high numbers of CT scans scheduled may have contributed to create this particular pattern of care.

Coronary artery calcification outperforms thoracic aortic calcification for the prediction of myocardial infarction and all-cause mortality: the Heinz Nixdorf Recall Study

BACKGROUND

Thoracic aortic calcification (TAC) is associated with cardiovascular (CV) risk factors and prevalent coronary artery disease. We aimed to investigate whether TAC burden is associated with incident myocardial infarction (MI) and all-cause mortality in subjects without known coronary artery disease and to determine its predictive value for these endpoints.

METHODS

We used longitudinal data from the population-based prospective Heinz Nixdorf Recall Study. TAC and coronary artery calcification (CAC) scores were quantified from non-contrast enhanced electron beam computed tomography. Cox regression analysis was used to determine the association of TAC with incident MI or all-cause mortality, adjusting for CV risk factors and additionally for CAC-score in a separate step. Predictive value of TAC was assessed using Harrell's C index.

RESULTS

Overall, 4040 participants without known coronary artery disease (59.4 years, 47% male) were included in this analysis. During a mean follow-up of 8.0 ± 1.5 years, we observed 136 coronary events and 304 deaths. In subjects with TAC>0 vs TAC = 0, the incidence of nonfatal MI was 4.2% vs 2.0% (p < 0.001), and all-cause mortality was 8.9% vs 5.2% (p < 0.001). Risks for coronary events and for all-cause mortality increased significantly with increasing TAC-scores (p < 0.001). After adjustment for CV risk factors, body mass index (BMI) and CV medication, a unit increase of TAC on a logarithmic scale (log(TAC + 1)) remained independently associated with coronary events (hazard ratio (HR) (95% confidence interval (CI)): 1.06 (1.00-1.14), p = 0.03) and all-cause mortality (HR 1.06 (1.01-1.12), p < 0.01). After further adjustment for CAC-score (log(CAC + 1)), hazard ratios were attenuated for both endpoints (coronary events: 0.98 (0.91-1.05), p = 0.56, all-cause mortality: 1.03 (0.98-1.08), p = 0.33). When adding log(TAC + 1) to the model containing traditional risk factors and CAC, Harrell's C indices did not increase for coronary events (0.773-0.772, p = 0.66) or for all-cause mortality (0.741-0.743, p = 0.49).

CONCLUSION

TAC is associated with incident coronary events and all-cause mortality independent of traditional CV risk factors in the general population. TAC fails to improve event prediction over CAC in both coronary events and all-cause mortality.

Cohort studies with low baseline response may not be generalisable to populations with different exposure distributions

Several advocates of mega-cohorts in epidemiology recently stated that high baseline response needs not be a driving scientific factor. We illustrate how cohort studies with low baseline response can become less generalisable than cohort studies with reasonable high baseline response. Assuming exposure prevalences of 32%, and 39% for former, and current smoking in the general population, we postulate that 10% in each group have a specific genotype G that makes them susceptible for the effect of smoking on the outcome (synergism between genotype and smoking). The existence and the mechanism of this synergism is unknown to the investigator. The parameter of interest is the average effect of smoking on the outcome expressed as relative risk (RR). We consider three different scenarios. In scenario 1, the RR for former and present smokers is 50 and 100 for subjects with G, translating into RR of 5.9 and 10.9 at population level. In scenario 2, the according figures are 10 and 20 for subjects with G and 1.9 and 2.9 at the population level, while in scenario 3, the according numbers are 2 and 5, and 1.1 and 1.4, respectively. We assume a differential baseline response by genotype G with overall baseline responses of 10% (low) and 50% (high). In all scenarios, we observe generalisability for a high baseline response. In contrast, for low baseline response the RRs for former and current smokers lack generalisability with loss of dose response relationship leading to 2.58 and 2.09 in scenario 1, to 1.29 and 1.21 in scenario 2, and in scenario 3 with RRs very close to unity (1.03 and 1.04 respectively). RR estimates may lack generalisability and dose response relationships even may be inverted if baseline response is low. Thus, even mega-cohorts should strive for a reasonable high baseline response.

Midday naps and the risk of coronary artery disease: results of the Heinz Nixdorf Recall Study

STUDY OBJECTIVES

Several studies have assessed the association between midday nap and cardiovascular outcomes and reported heterogenous results. Concern exists that confounding might have distorted these results and contributed to discrepancies among them. This study prospectively examines the association between midday nap habits and the occurrence of coronary artery disease in a non-Mediterranean population.

PARTICIPANTS

The baseline examination of 4,123 participants aged 45-75 years.

MEASUREMENTS

Measurements included interviews, physical examinations, laboratory tests, and electron beam computed tomography. We studied the influence of midday nap habits on risk of coronary artery disease. We adjusted for several potential confounders including measures of subclinical atherosclerosis-such as coronary calcium score and ankle brachial index-at baseline. Cardiac events during a median follow-up of 8.1 years were defined as nonfatal myocardial infarction and sudden cardiac death.

RESULTS

Overall, 135 of 4,123 subjects (3.3%) either suffered from acute myocardial infarction (81 subjects) or died due to a sudden cardiac death (54 subjects) during follow-up. After adjustment for several confounders including measures of subclinical atherosclerosis, regular long (> 60 min) midday nap was associated with an increased hazard ratio of cardiac events (hazard ratio 2.12, 95% confidence interval 1.11-4.05).

CONCLUSIONS

As our detailed confounder analyses showed, confounding is not the sole explanation for this finding. Future research on midday naps should focus on biological mechanisms that may be responsible for increasing the risk of coronary artery disease among subjects taking regular long midday naps.

Mammographic density and inter-observer variability of pathologic evaluation of core biopsies among women with mammographic abnormalities

BACKGROUND

As high percentage of mammographic densities complicates the assessment of imaging findings, mammographic density may influence the histopathological evaluation of core-biopsies of the breast. We measured the influence of mammographic density on the inter-observer variability of histopathological findings of breast biopsies.

METHODS

Histological slides of 695 women who underwent core biopsies of the breast at University of Halle between 2006 and 2008 were evaluated in a blinded fashion by two pathologists using the five levels of the B-categorization scheme (B1-B5). To quantify mammographic density, we used a computer-based threshold method (Madena). We calculated observed and chance-corrected agreements (weighted kappa) and 95% confidence intervals (95% CI) according to four categories of mammographic density (<10%, 10<25%, 25<50%, ≥50%).

RESULTS

The weighted kappa decreased monotonically from 89.6% (95% CI: 85.8%, 93.3%) among women with less than 10% of mammographic density to 80.4% (95% CI: 69.9%, 90.9%) for women with more than 50% of mammographic density, respectively. Results of a kappa regression analysis showed that agreement of pathologists on clinically relevant categories (B1-B2 versus B3-B5) decreased with mammographic density.

CONCLUSIONS

Mammographic density is a relevant modifier of the agreement between pathologists who assess breast biopsies using the B-categorization scheme. The influence of mammographic density on the inter-observer variability can be explained to some extent by varying prevalences of histological entities across B categories that have typically different inter-observer agreement. Women with high mammographic density are at higher risk of inter-observer variability compared to women with low mammographic density and should possibly undergo a second pathology review.

Insomnia and urban neighbourhood contexts--are associations modified by individual social characteristics and change of residence? Results from a population-based study using residential histories

Background

Until now, insomnia has not been much of interest in epidemiological neighbourhood studies, although literature provides evidence enough for insomnia-related mechanisms being potentially dependent on neighbourhood contexts. Besides, studies have shown differences in sleep along individual social characteristics that might render residents more vulnerable to neighbourhood contextual exposures. Given the role of exposure duration and changes in the relationship between neighbourhoods and health, we studied associations of neighbourhood unemployment and months under residential turnover with insomnia by covering ten years of residential history of nearly 3,000 urban residents in the Ruhr Area, Germany.

Methods

Individual data were retrieved from the Heinz Nixdorf Recall Study, a population-based study of randomly chosen participants from adjacent cities, which contains self-rated insomnia symptoms and individual social characteristics. Participants’ residential addresses were retrospectively assessed using public registries. We built individually derived exposure measures informing about mean neighbourhood unemployment rates and months under high residential turnover. These measures were major predictors in multivariate logistic regressions modelling the association between social neighbourhood characteristics and insomnia in the whole sample and subgroups defined by low income, low education, social isolation, and change of residence. Traffic-related noise, age, gender, economic activity, and education were considered as covariates.

Results

Nearly 12 per cent of the participants complained about insomnia. Associations of neighbourhood unemployment with insomnia were more consistent than those of residential turnover in the whole sample (adjusted OR 1.42, 95% CI 1.00-2.03 for neighbourhood unemployment and OR 1.33, 95% CI 0.78-2.25 for residential turnover in the highest exposure categories). In low-income and socially isolated participants, neighbourhood unemployment odds of reporting insomnia were particularly elevated (adjusted OR 2.90, 95% CI 1.39-6.02 and OR 3.32, 95% CI 1.11-9.96, respectively). Less educated participants displayed relatively high odds of reporting insomnia throughout all upper neighbourhood unemployment exposure categories. Change of residence weakened associations, whereas undisrupted exposure sharpened them by trend.

Conclusions

Our findings hint at multiple stressors being effective in both the neighbourhood context and individual resident, possibly reflecting precarious life situations undermining residents’ sleep and health chances. Moreover, our results suggest a temporal dependency in the association between neighbourhood and insomnia.