ABSTRACT
Microbial ecological functions are an emergent property of community composition. For some ecological functions this link is strong enough that community composition can be used to estimate the quantity of an ecological function. Here, we apply random forest regression models to compare the predictive performance of community composition and environmental data for bacterial production (BP). Using data from two independent long-term ecological research sites - Palmer LTER in Antarctica and Station SPOT in California - we found that community composition was a strong predictor of BP. The top performing model achieved an R2 of 0.84 and RMSE of 20.2 pmol L-1 hr-1 on independent validation data, outperforming a model based solely on environmental data (R2 = 0.32, RMSE = 51.4 pmol L-1 hr-1). We then operationalized our top performing model, estimating BP for 346 Antarctic samples from 2015-2020 for which only community composition data were available. Our predictions resolved spatial trends in BP with significance in the Antarctic (P value = 1 x 10-4) and highlighted important taxa for BP across ocean basins. Our results demonstrate a strong link between microbial community composition and microbial ecosystem function and begin to leverage long-term datasets to construct models of BP based on microbial community composition.
ABSTRACT
The Antarctic marine environment is a dynamic ecosystem where microorganisms play an important role in key biogeochemical cycles. Despite the role that microbes play in this ecosystem, little is known about the genetic and metabolic diversity of Antarctic marine microbes. In this study we leveraged DNA samples collected by the Palmer Long Term Ecological Research (LTER) project to sequence shotgun metagenomes of 48 key samples collected across the marine ecosystem of the western Antarctic Peninsula (wAP). We developed an in silico metagenomics pipeline (iMAGine) for processing metagenomic data and constructing metagenome-assembled genomes (MAGs), identifying a diverse genomic repertoire related to the carbon, sulfur, and nitrogen cycles. A novel analytical approach based on gene coverage was used to understand the differences in microbial community functions across depth and region. Our results showed that microbial community functions were partitioned based on depth. Bacterial members harbored diverse genes for carbohydrate transformation, indicating the availability of processes to convert complex carbons into simpler bioavailable forms. We generated 137 dereplicated MAGs giving us a new perspective on the role of prokaryotes in the coastal wAP. In particular, the presence of mixotrophic prokaryotes capable of autotrophic and heterotrophic lifestyles indicated a metabolically flexible community, which we hypothesize enables survival under rapidly changing conditions. Overall, the study identified key microbial community functions and created a valuable sequence library collection for future Antarctic genomics research.
ABSTRACT
Islands support unique plants, animals, and human societies found nowhere else on the Earth. Local and global stressors threaten the persistence of island ecosystems, with invasive species being among the most damaging, yet solvable, stressors. While the threat of invasive terrestrial mammals on island flora and fauna is well recognized, recent studies have begun to illustrate their extended and destructive impacts on adjacent marine environments. Eradication of invasive mammals and restoration of native biota are promising tools to address both island and ocean management goals. The magnitude of the marine benefits of island restoration, however, is unlikely to be consistent across the globe. We propose a list of six environmental characteristics most likely to affect the strength of land-sea linkages: precipitation, elevation, vegetation cover, soil hydrology, oceanographic productivity, and wave energy. Global databases allow for the calculation of comparable metrics describing each environmental character across islands. Such metrics can be used today to evaluate relative potential for coupled land-sea conservation efforts and, with sustained investment in monitoring on land and sea, can be used in the future to refine science-based planning tools for integrated land-sea management. As conservation practitioners work to address the effects of climate change, ocean stressors, and biodiversity crises, it is essential that we maximize returns from our management investments. Linking efforts on land, including eradication of island invasive mammals, with marine restoration and protection should offer multiplied benefits to achieve concurrent global conservation goals.
Subject(s)
Conservation of Natural Resources , Ecosystem , Animals , Humans , Biodiversity , Introduced Species , Climate Change , MammalsABSTRACT
Solutions to complex and unprecedented global challenges are urgently needed. Overcoming these challenges requires input and innovative solutions from all experts, including Early Career Ocean Professionals (ECOPs). To achieve diverse inclusion from ECOPs, fundamental changes must occur at all levels-from individuals to organizations. Drawing on insights from across the globe, we propose 5 actionable pillars that support the engagement of ECOPs in co-design processes that address ocean sustainability: sharing knowledge through networks and mentorship, providing cross-boundary training and opportunities, incentivizing and celebrating knowledge co-design, creating inclusive and participatory governance structures, and catalyzing culture change for inclusivity. Foundational to all actions are the cross-cutting principles of justice, equity, diversity, and inclusivity. In addition, the pillars are cross-boundary in nature, including collaboration and innovation across sectors, disciplines, regions, generations, and backgrounds. Together, these recommendations provide an actionable and iterative path toward inclusive engagement and intergenerational exchange that can develop ocean solutions for a sustainable future.
Subject(s)
Conservation of Natural Resources , Humans , Oceans and SeasABSTRACT
Microbial taxonomic marker gene studies using 16S rRNA gene amplicon sequencing provide an understanding of microbial community structure and diversity; however, it can be difficult to infer the functionality of microbes in the ecosystem from these data. Here, we show how to predict metabolism from phylogeny using the paprica pipeline. This approach allows resolution at the strain and species level for select regions on the prokaryotic phylogenetic tree and provides an estimate of gene and metabolic pathway abundance. For complete details on the use and execution of this protocol, please refer to Erazo and Bowman (2021).
Subject(s)
Computational Biology/methods , Microbiota , Sequence Analysis, RNA/methods , Genome, Archaeal , Genome, Bacterial , Metabolic Networks and Pathways , PhylogenyABSTRACT
A multitude of concurrent biological and physical processes contribute to microbial community turnover, especially in highly dynamic coastal environments. Characterizing what factors contribute most to shifts in microbial community structure and the specific organisms that correlate with changes in the products of photosynthesis improves our understanding of nearshore microbial ecosystem functions. We conducted high frequency sampling in nearshore Southern California in order to capture sub-weekly microbial community dynamics. Microbial communities were characterized by flow cytometry and 16S rRNA gene sequencing, and placed in the context of physicochemical parameters. Within our time-series, season and nutrient availability corresponded to changes in dominant microbial community members. Concurrent aseasonal drivers with overlapping scales of variability were also apparent when we used network analysis to assess the microbial community as subsets of the whole. Our analyses revealed the microbial community as a mosaic, with overlapping groups of taxa that varied on different timescales and correlated with unique abiotic and biotic factors. Specifically, a subnetwork associated with chlorophyll a exhibited rapid turnover, indicating that ecologically important subsets of the microbial community can change on timescales different than and in response to factors other than those that govern turnover of most members of the assemblage.
Subject(s)
Microbiota , California , Chlorophyll A , Microbiota/genetics , RNA, Ribosomal, 16S/genetics , SeasonsABSTRACT
Mangrove-dominated estuaries host a diverse microbial assemblage that facilitates nutrient and carbon conversions and could play a vital role in maintaining ecosystem health. In this study, we used 16S rRNA gene analysis, metabolic inference, nutrient concentrations, and δ13C and δ15N isotopes to evaluate the impact of land use change on near-shore biogeochemical cycles and microbial community structures within mangrove-dominated estuaries. Samples in close proximity to active shrimp aquaculture were high in NH4 +, NO3 - NO2 -, and PO4 3-; lower in microbial community and metabolic diversity; and dominated by putative nitrifiers, denitrifies, and sulfur-oxidizing bacteria. Near intact mangrove forests we observed the presence of potential nitrogen fixers of the genus Calothrix and order Rhizobiales. We identified possible indicators of aquaculture effluents such as Pseudomonas balearica, Ponitmonas salivi brio , family Chromatiaceae, and genus Arcobacter. These results highlight the sensitivity of the estuarine-mangrove microbial community, and their ecosystem functions, to land use changes.
ABSTRACT
Concurrent osmotic and chaotropic stress make MgCl2 -rich brines extremely inhospitable environments. Understanding the limits of life in these brines is essential to the search for extraterrestrial life on contemporary and relict ocean worlds, like Mars, which could host similar environments. We sequenced environmental 16S rRNA genes and quantified microbial activity across a broad range of salinity and chaotropicity at a Mars-analogue salt harvesting facility in Southern California, where seawater is evaporated in a series of ponds ranging from kosmotropic NaCl brines to highly chaotropic MgCl2 brines. Within NaCl brines, we observed a proliferation of specialized halophilic Euryarchaeota, which corresponded closely with the dominant taxa found in salterns around the world. These communities were characterized by very slow growth rates and high biomass accumulation. As salinity and chaotropicity increased, we found that the MgCl2 -rich brines eventually exceeded the limits of microbial activity. We found evidence that exogenous genetic material is preserved in these chaotropic brines, producing an unexpected increase in diversity in the presumably sterile MgCl2 -saturated brines. Because of their high potential for biomarker preservation, chaotropic brines could therefore serve as repositories of genetic biomarkers from nearby environments (both on Earth and beyond) making them prime targets for future life-detection missions.
Subject(s)
Salinity , Seawater , Oceans and Seas , RNA, Ribosomal, 16S/genetics , Sodium Chloride/analysisABSTRACT
Mangrove ecosystems provide important ecological benefits and ecosystem services, including carbon storage and coastline stabilization, but they also suffer great anthropogenic pressures. Microorganisms associated with mangrove sediments and the rhizosphere play key roles in this ecosystem and make essential contributions to its productivity and carbon budget. Understanding this nexus and moving from descriptive studies of microbial taxonomy to hypothesis-driven field and lab studies will facilitate a mechanistic understanding of mangrove ecosystem interaction webs and open opportunities for microorganism-mediated approaches to mangrove protection and rehabilitation. Such an effort calls for a multidisciplinary and collaborative approach, involving chemists, ecologists, evolutionary biologists, microbiologists, oceanographers, plant scientists, conservation biologists, and stakeholders, and it requires standardized methods to support reproducible experiments. Here, we outline the Mangrove Microbiome Initiative, which is focused around three urgent priorities and three approaches for advancing mangrove microbiome research.
ABSTRACT
El interés actual del estudio de Staphylococcus aureus deriva de su elevada frecuencia de cepas resistentes a los antibióticos que causa frecuentes brotes de infección, especialmente, el S. aureus con resistencia a meticilina (SARM). El objetivo de esta revisión fue estudiar la estructura genética poblacional y el origen de los aislamientos de SARM. La tipificación del cassette cromosómico mec estafilocócico es el método más importante para identificar y definir la naturaleza clonal del S. aureus con resistencia a meticilina. Los estudios de epidemiología molecular evidencian un patrón de diseminación de unas pocas cepas que son las responsables del importante problema mundial. Existe el predominio de clones pandémicos de SARM asociado a infecciones hospitalarias (SARM-AH), que ha han sido reemplazados en la actualidad por clones de origen comunitario (SARM-AC). En Colombia, predomina el clon pediátrico y el chileno entre los aislamientos hospitalarios. Sin embargo, en la actualidad una variante del clon comunitario USA300 prevalece en las infecciones adquiridas en la comunidad y en el hospital, desplazando los clones hospitalarios como ocurre en el resto de mundo. El entendimiento de la epidemiología y clonalidad de las infecciones por S. aureus tiene importantes implicaciones en el control de la emergencia de cepas con multirresistencia y el esparcimiento de clones resistentes y sensibles a meticilina.
Recent interest in the study of Staphylococcus aureus derives from the high frequency of antibiotic-resistant strains that cause frequent outbreaks of infection, especially Methicillin-resistant S. aureus (MRSA). The objective of this review was to study the population genetic structure and the origin of MRSA isolation. Classification of staphylococcal cassette chromosome mec (SCCmec) is the most important method to identify and define the S. aureus methicillin-resistant clonal nature. Molecular epidemiologic studies have demonstrated dissemination patterns of few strains which are responsible for the important worldwide problem. There is a predominance of pandemic clones of MRSA associated to hospital-acquired infections (HA-MRSA) which has been replaced today by community-acquired strains (CA-MRSA). In Colombia, the pediatric clone and the Chilean clone predominate between hospital isolations. However, currently, there is a variant community clone USA300 prevailing in infections acquired in the community and in the hospital, displacing HA-MRSA as it happens in the rest of world. Understanding the epidemiology and clonality of S. aureus infections has important implications for future efforts to control of the emergence of multidrug-resistant strains and the spread of clones resistant and sensible to methicillin.
ABSTRACT
BACKGROUND: Suicide prediction during psychiatric in-patient treatment remains an unresolved challenge. AIMS: To identify determinants of railway suicides in individuals receiving in-patient psychiatric treatment. METHOD: The study population was drawn from patients admitted to six psychiatric hospitals in Germany during a 10-year period (1997-2006). Data from 101 railway suicide cases were compared with a control group of 101 discharged patients matched for age, gender and diagnosis. RESULTS: Predictors of suicide were change of therapist (OR = 22.86, P = 0.004), suicidal ideation (OR = 7.92, P<0.001), negative or unchanged therapeutic course (OR = 7.73, P<0.001), need of polypharmaceutical treatment (OR = 2.81, P = 0.04) and unemployment (OR = 2.72, P = 0.04). Neither restlessness nor impulsivity predicted in-patient suicide. CONCLUSIONS: Suicidal ideation, unfavourable clinical course and the use of multiple psychotropic substances (reflecting the severity of illness) were strong determinants of railway suicides. The most salient finding was the vital impact of a change of therapist. These findings deserve integration into the clinical management of patients with serious mental disease.
Subject(s)
Hospitals, Psychiatric , Inpatients/psychology , Suicide/psychology , Unemployment/psychology , Adult , Case-Control Studies , Female , Humans , Male , Middle Aged , Patient Discharge , Risk Factors , Suicidal Ideation , Suicide, Attempted/psychologyABSTRACT
OBJECTIVE: The present study addressed potential harms of a negative working environment for employed subjects. The main aim was to evaluate if adverse working conditions and job strain are related to an increase in suicide mortality. METHODS: The study population consisted of 6817 participants drawn from the MONICA/KORA Augsburg, Germany, surveys conducted in 1984-1995, being employed at baseline examination and followed up on average for 12.6 years. Adverse working conditions were assessed by an instrument of 16 items about chronobiological, physical and psychosocial conditions at the workplace, job strain was assessed as defined by Karasek. Suicide risks were estimated by Cox regression adjusted for suicide-related risk factors. RESULTS: A number of 28 suicide cases were observed within follow-up. High levels of adversity in chronobiological/physical working conditions significantly increased the risk for suicide mortality (HR 3.28, 95% CI 1.43-7.54) compared to low/intermediate levels in a model adjusted for age, sex and survey (p value 0.005). Additional adjustment for living alone, low educational level, smoking, high alcohol consumption, obesity and depressed mood attenuated this effect (HR 2.73) but significance remained (p value 0.022). Adverse psychosocial working conditions and job strain, in contrast, had no impact on subsequent suicide mortality risk (p values > 0.200). CONCLUSIONS: A negative working environment concerning chronobiological or physical conditions at the workplace had an unfavourable impact on suicide mortality risk, even after controlling for relevant suicide-related risk factors. Employer interventions aimed to improve workplace conditions might be considered as a suitable means to prevent suicides among employees.
Subject(s)
Employment/psychology , Stress, Psychological/complications , Suicide/psychology , Suicide/statistics & numerical data , Workplace/psychology , Adult , Affect , Aged , Alcohol Drinking/psychology , Depression/psychology , Female , Follow-Up Studies , Germany/epidemiology , Humans , Male , Middle Aged , Obesity/psychology , Risk Factors , Smoking/psychologyABSTRACT
BACKGROUND: The majority of fatalities on the European Union (EU) railways are suicides, representing about 60% of all railway fatalities. The aim of this study was to compare time patterns of suicidal behaviour on railway tracks in Germany between two observation periods (1995-1998 and 2005-2008) in order to investigate their stability and value in railway suicide prevention. METHODS: Cases were derived from the National Central Registry of person accidents on the German railway network (STABAG). The association of daytime, weekday and month with the mean number of suicides was analysed applying linear regression. Potential differences by observation period were assessed by adding observation period and the respective interaction terms into the linear regression. A 95% confidence interval for the mean number of suicides was computed using the t distribution. RESULTS: A total of 7,187 railway suicides were recorded within both periods: 4,102 (57%) in the first period (1995-1998) and 3,085 (43%) in the second (2005-2008). The number of railway suicides was highest on Mondays and Tuesdays in the first period with an average of 3.2 and 3.5 events and of 2.6 events on both days in the second period. In both periods, railway suicides were more common between 6:00 am and noon, and between 6:00 pm and midnight. Seasonality was only prominent in the period 1995-1998. CONCLUSIONS: Over the course of two observation periods, the weekday and circadian patterns of railway suicides remained stable. Therefore, these patterns should be an integral part of railway suicide preventive measures, e.g. gatekeeper training courses.
Subject(s)
Railroads/statistics & numerical data , Suicide/statistics & numerical data , Germany/epidemiology , Humans , Periodicity , Registries/statistics & numerical dataABSTRACT
BACKGROUND: Suicide is strongly associated with mental disorders, particularly with depression. There is insufficient knowledge to what extent sociodemographic and behavioral characteristics contribute to suicide risk. METHODS: A population-based cohort study on three independent cross-sectional MONICA/KORA Augsburg surveys with 12,888 subjects (6456 men, 6432 women) was followed up on average for 12.0 years. Information on sociodemographic characteristics, chronic disease conditions, smoking habits, alcohol consumption, depressive symptoms, personality type, and other psychodiagnostic parameters was assessed by standardized interviews. Cox proportional hazards regression analyses were used to compute hazard ratios (HRs) as estimates of relative risks for suicide mortality. Additionally, population-attributable risks were calculated. RESULTS: Within the follow-up period, a total of 1449 persons had died, 38 of them by suicide. Although several variables were associated with increased risk in the basic analyses, only obesity (HR=2.73), smoking (HR=2.23), and living alone (HR=2.19) remained significantly associated with suicide additionally to male sex (HR=3.57) and depressed mood (HR=2.01) in a multivariate analysis. LIMITATIONS: The generalization of our findings to countries with different social, economic or cultural conditions may be questioned. CONCLUSIONS: Our findings extend the knowledge about sociodemographic and behavioral risk factors for suicide in the general population: Suicide prevention measures should not consider only subjects with mental disorders but also address other adverse conditions.
Subject(s)
Depression/psychology , Obesity/psychology , Single Person/psychology , Smoking/psychology , Suicide/psychology , Adult , Affect , Cohort Studies , Cross-Sectional Studies , Depression/epidemiology , Female , Humans , Male , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Risk Factors , Sex Factors , Suicide/statistics & numerical dataABSTRACT
AIM: To assess suicide mortality in comparison to traffic accidents and homicide deaths in Germany in the year 2010 and to compare years of life lost (YLL) due to these unnatural deaths. METHODS: Mortality data were provided by the Federal Statistical Office giving death rates (related to 100,000 inhabitants) and proportions (related to 100 deaths of individuals) for suicide, traffic accidents and homicide as well as YLL data. RESULTS: A total of 14,441 unnatural deaths (suicide, traffic accidents, homicide) were reported in 2010 in Germany. Of those, 10,021 subjects (69.4%) committed suicide, 3,942 (27.3%) died in traffic accidents, 478 (3.3%) were murdered. Suicide death rates were by far the highest, with rates for men (18.6) three times higher than for women (6.1). For both sexes, suicide rates increased with age, whereas suicide as a proportion of all causes of death was higher in younger age groups. In both sexes, suicide was the leading cause of YLL (men: 314 YLL, women: 90 YLL). CONCLUSIONS: Suicide is the leading cause of unnatural death and YLL. The sex- and age- specific patterns in suicide mortality call for different action plans to target high risk groups.
Subject(s)
Accidents, Traffic/mortality , Homicide/statistics & numerical data , Suicide/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Cause of Death , Child , Child, Preschool , Female , Germany , Humans , Infant , Male , Middle Aged , Young AdultABSTRACT
BACKGROUND: Smoking and heavy alcohol use predicts suicidal behaviour. Whether the simultaneous presentation of both conditions induces an amplified effect on risk prediction has not been investigated so far. METHODS: In a community-based cohort study, a total of 12,888 subjects (6,456 men, 6,432 women; age range of 25-74 years at assessment) from three independent population-based cross-sectional MONICA surveys (conducted in 1984/85, 1989/90, and 1994/95), representative for the Southern German population, was followed up until 31 December 2002. Standardized mortality ratios (SMR) for deaths from suicide using German population rates were calculated for smoking and high alcohol consumption. RESULTS: After a mean follow-up time of 12.0 (SD 4.4) years and 154,275 person-years at risk, a total of 1,449 persons had died from all causes and 38 of them from suicide. Compared to the general population, mortality from suicide was increased for risky alcohol consumption (SMR = 2.37; 95% CI 1.14-4.37) and for smoking (SMR = 2.30; 95% CI 1.36-3.63). A substantial increase in suicide mortality (SMR = 4.80; 95% CI 2.07-9.46) was observed for smokers with risky alcohol consumption. CONCLUSIONS: The approximately fourfold increased relative risk for completed suicide in subjects with smoking and risky alcohol consumption indicates a synergistic effect which deserves an increased alertness.
Subject(s)
Alcohol Drinking/epidemiology , Smoking/epidemiology , Suicide/trends , Adult , Aged , Cohort Studies , Female , Germany/epidemiology , Health Surveys , Humans , Male , Middle Aged , Risk AssessmentABSTRACT
Current knowledge on behavioural patterns and personal characteristics of subjects who choose the railway as means of suicide is sparse. The aim of this study was to determine the frequency of three distinct behaviour patterns (jumping, lying, wandering) in railway suicides and to explore associated variables. Cases were derived from the National Central Registry of person accidents on the German railway net covering the period from 2002 to 2006. A retrospective analysis of registry protocols of all 4127 suicidal acts allowed classification of behaviour patterns in 1004 cases. Types of suicidal behaviour occurred with nearly equal frequencies; jumping in 32.2%, lying in 32.6% and wandering in 34.2% of cases. Age and sex were not associated with type of suicidal behaviour. The proportion of jumping was highest during 9:01 am to 6:00 pm while at night, lying was used most frequently. Jumping predominated in the station area, while lying and wandering on the open track. Fatality was highest in liers and lowest in jumpers. The frequency of jumping decreased during the study period by 12.6% (p < .05). These findings may help to elucidate differential risk features of this highly lethal suicide method.
Subject(s)
Information Services , Railroads , Suicide, Attempted , Adult , Analysis of Variance , Chi-Square Distribution , Female , Germany/epidemiology , Humans , Information Services/statistics & numerical data , Male , Middle Aged , Railroads/statistics & numerical data , Retrospective Studies , Seasons , Suicide, Attempted/classification , Suicide, Attempted/psychology , Suicide, Attempted/statistics & numerical data , Time FactorsABSTRACT
Understanding factors associated with death wishes and suicidal ideation (SID) may help to improve identification of subjects at risk in the general population. We assessed SID in a population-based sample of 3079 subjects, 35 to 84 years and examined multiple sex- and age-adjusted affective and bio-behavioral covariates. Anxiety and a high level of somatic complaints, particularly dyspnea, contributed to the SID risk. However, the clinical picture of subjects suffering from SID was dominated by a 6-fold adjusted increased risk of a depressive syndrome followed by impaired self perceived health (3-fold risk) in both sexes. In men, unemployment status and living alone also increased SID risk substantially. These factors open new insights for our understanding of the multifaceted etiology of suicide risks offering new strategies for early detection of subjects at risk.
Subject(s)
Attitude to Death , Depressive Disorder/diagnosis , Suicide/psychology , Adult , Age Factors , Aged , Aged, 80 and over , Anxiety Disorders/diagnosis , Anxiety Disorders/epidemiology , Anxiety Disorders/psychology , Data Collection , Depressive Disorder/epidemiology , Depressive Disorder/psychology , Female , Germany/epidemiology , Health Status , Health Surveys , Humans , Male , Psychiatric Status Rating Scales , Risk Assessment , Risk Factors , Sex Factors , Somatoform Disorders/diagnosis , Somatoform Disorders/epidemiology , Somatoform Disorders/psychology , Suicide/statistics & numerical data , Surveys and Questionnaires , Suicide PreventionABSTRACT
Among risk factors for suicide, suicidal ideation (SID) is of paramount importance. This study sought to determine sex- and age-related SID point prevalence rates in the general population. A population-based survey of 3154 subjects, 35 to 84 years, conducted in 2004/05 in southern Germany, identified 170 subjects (5.4%; 95% CI 4.6-6.2) suffering from SID within the last 14 days. Age-adjusted short-term period prevalence in women (6.0%, 95% CI 4.9.-7.2) was higher than in men (4.0%, 95% CI 3.1-5.1). Among 10-year age groups, sex-related differences were only significant in middle-aged subjects (55-64 years). Prevalence increased significantly with age, leading to a prevalence of >10% in the oldest age group (75-84 years). The population-based approach demonstrates a substantial proportion of subjects suffering from SID, particularly in older age groups.