Several epidemiological studies have indicated that building dampness affects the respiratory health of the inhabitants. In this study we. In this study, we investigated the relationship between building dampness and In, as a part of the European Community Respiratory Health Survey stage. The likelyhood of toxic health effects (i.e. not allergies) caused by inhaling toxic evidence of an association between indoor dampness-related factors and a.
Asthma development is a health outcome of particular public health importance. Five case—control studies included in the Institute of Medicine review of the eight on asthma development in Table A1. Four new studies were identified for the current review Jaakkola, Hwang, Jaakkola, ; Matheson et al. In both studies of infants, all the ORs exceeded 1. These studies were not included in the meta-analysis of Fisk, Lei-Gomez and Mendellwhich found a summary OR of 1. One of the strongest reported studies Pekkanen et al.
The multivariate-adjusted ORs for asthma incidence associated with three levels of maximum severity of moisture damage assessed by civil engineers were 1. This well-designed study is the strongest available piece of evidence within a body of generally consistent findings that dampness-related exposure is not only associated with, but may cause, asthma in infants and children.
For dyspnoea, for which the Institute of Medicine considered there was limited or suggestive evidence of an association with dampness, the number of studies in adults and children had doubled to eight, although they were all still cross-sectional. In the available studies Tables A1. Current asthma, which was not evaluated in the Institute of Medicine review, was consistently associated in the available studies Table A1. Respiratory infections were also not evaluated in the Institute of Medicine review.
Of the available studies of qualitative dampness-related factors and respiratory infections Table A1. The few findings on otitis media, in three studies of children, showed estimates ranging from 1.
Outcomes evaluated in this review Table A1. There was some suggestion that indoor dampness was associated with allergic rhinitis, but the evidence was inconsistent.
Our review did not include studies on the health effects of moisture and microbiological growth within heating, ventilation and air-conditioning systems, although these are potentially common effects in buildings with air-conditioning systems or humidification. A number of studies suggested increased risks of building-related symptoms, including lower respiratory tract symptoms, due to poorly designed or maintained heating, ventilating and air-conditioning systems e.
These effects appeared probably to be due to uncharacterized microbiological agents. The strongest study on this question is that of Menzies et al.
The study showed that ultraviolet germicidal irradiation of the wet surfaces of cooling coils and condensate drippans in heating, ventilation and air-conditioning systems substantially reduced symptoms among the occupants. The findings suggest that microorganisms growing on moist surfaces in typical commercial air-conditioning systems can substantially increase building-related symptoms. The findings also imply that atopic people and nonsmokers are more responsive to microbiological agents in the form of increased respiratory and musculoskeletal symptoms.
This pattern of susceptibility is similar to that for hypersensitivity pneumonitis and may indicate a milder subclinical process. Hypersensitivity pneumonitis-like illness caused by indoor work environments has been reported repeatedly, generally in relation to leaks, but is considered rare Kreiss, A possible explanation for these findings can be found in the reports of Gorny and others, who have shown that fungi and actinomycetes can emit large numbers of airborne particles smaller than spores Gorny et al.
Uncertainty It is helpful to explore, as far as is feasible, how the findings of studies are influenced by various aspects of quality, including the quality of measurements of exposures and health outcomes.
For instance, two reviews addressed the possibility that biased responses by building occupants in studies of dampness distort the findings.
Fisk, Lei-Gomez and Mendell considered information on this question in six studies and concluded that the associations observed between respiratory health effects and dampness-related exposure were unlikely to be explained by overreporting of dampness or mould by people with respiratory symptoms.
The findings could also be compared on the basis of whether assessment of exposure was qualitative or quantitative. Random error in crude qualitative exposure categories tends to reduce the ability of studies to reveal true associations. The objective measures of exposure used in the studies have important limitations see also Chapter 2. First, measurement of concentrations of culturable microorganisms is known to incur substantial error, due, for example, to short-term estimation of airborne concentrations that vary widely and rapidly over time, to the differential ability of organisms to grow on specific culture media and to the inability of culture assays to identify most bioactive microbial materials, whether intact spores or fragments.
Second, the quantitative microbial measurements used in some of the studies cannot be considered to be inherently more accurate for assessing exposure, as the microbes may not be relevant causal factors. The exposures that cause dampness-related illness have not yet been determined.
A study of an association between health effects and the concentration of a specific microorganism or microbial compound is in fact testing a hypothesis. In the studies in our review, such hypothetical causal exposures included all culturable fungi, specific culturable fungi, all fungal spores, species-specific spores, all fungal biomass ergosterol Robine et al.
Avoidance behaviour is another source of exposure misclassification; that is, people with asthma might change their living environment to reduce exposure. This is a concern mainly in cross-sectional and case-control studies, in which it can lead to an underestimate of the true effect. It is of no concern in those studies in which exposure is assessed before the onset of asthma.
Finally, the lack of standardization of the definitions of health effects can result in bias. In population studies, for instance, asthma is usually defined on the basis of self-reported or parent-reported asthma symptoms, which include wheeze, chest tightness, breathlessness and cough. Self-reports of doctor-diagnosed asthma are also often used. An alternative to questionnaires has been the use of more objective measures, such as bronchial responsiveness testing, either alone or in combination with questionnaires.
As with measures of house dampness or fungal exposure, differences in asthma definition are likely to result in different estimates of prevalence and of relative risks. Also, as mentioned above, several studies Nafstad et al. Most of these potential sources of bias can result in underestimates of the true association between indoor damp and health effects.
The hygiene hypothesis Many studies have found that health risks are increased by exposure to microbes, but others suggest that exposure in early life to endotoxins or fungal agents protects against atopy and allergic disease. This potentially protective effect is consistent with the hygiene hypothesis, which postulates that growing up in a microbiologically hygienic environment might increase the risk of developing allergies Liu, Leung, This hypothesis was prompted by the results of epidemiological studies showing that overcrowding and unhygienic conditions were associated with lower prevalences of allergies, eczema and hay fever Strachan, A more recent review confirmed the associations between large family size, low socioeconomic status and hepatitis A infection and decreased risks of atopy, hay fever or eczema, but not for asthma Strachan, Exposure to certain microbial agents, including bacterial endotoxins, early in life has been proposed as an explanation for these protective effects Douwes et al.
Several cross-sectional studies showed significant inverse associations between indoor endotoxin levels and atopic sensitization, hay fever and atopic asthma Gereda et al. A recent prospective birth cohort study showed an inverse association between the levels of both bacterial endotoxins and fungal components measured at three months on the floor and doctor-diagnosed asthma and persistent wheeze at age 4 years, confirming some of the earlier findings of the cross-sectional studies Douwes et al.
A similar birth cohort study found a protective effect against atopy in children aged 2 years Bottcher et al. The evidence has not, however, been consistent Liu, ; von Mutius, Several large studies showed either no protective effect or even a positive association.
For instance, the National Survey of Allergens and Endotoxin in Housing in the United States showed an exposure-dependent increase in diagnosed asthma, wheeze and use of asthma medication in adults with increasing endotoxin concentrations in the bedroom floor and bedding Thorne et al. Some of the inconsistency may be due to the timing of exposure, being protective in early life and being a risk factor later in life.
Alternatively, exposure to endotoxins may prevent allergic asthma, but at higher exposure may cause non-allergic asthma Douwes, Pearce, Heederik, It is provocative that many well-conducted studies showed apparent protective effects of measured exposures to microbial agents, such as endotoxins and fungi. Other studies have shown that greater exposure to endotoxins is associated with decreased risks of atopy Gehring et al.
Li and Hsu reported the results of a cross-sectional study in which the concentrations of culturable Penicillium in indoor air were inversely associated with allergic rhinitis.
The findings are not, however, consistent. For instance, Dharmage et al. Overall, the available evidence is still inconsistent, and further research is required for clarification. Thus, modest exposure to microbial agents may, under certain circumstances, protect against allergies and allergic disease, but the evidence is inconsistent.
There is no indication that living or working in a damp building with heavy exposure to mould prevents the development of allergies and respiratory disease. Conclusions Our review of the epidemiological evidence presented in this report, the previous review by the Institute of Medicine and the quantitative meta-analysis of Fisk, Lei-Gomez and Mendell leads us to conclude that there is sufficient evidence of an association between indoor dampness-related factors and a wide range of respiratory health effects Table 8including asthma development, asthma exacerbation, current asthma, respiratory infections, upper respiratory tract symptoms, cough, wheeze and dyspnoea.
As we did not perform a formal meta-analysis, we cannot make a quantitative assessment of the relative risk; however, the quantitative summary estimates of associations between qualitatively assessed dampness or mould in residences and selected respiratory health effects provided by Fisk, Lei-Gomez and Mendell Table 7 are valid, as few additional studies of this type have become available.
As these estimates are based on limited data, broad lumping of diverse risk factors and multiple unverified assumptions, they should be interpreted cautiously; however, they do indicate that dampness-related risk factors may contribute substantially to the burden of respiratory disease.
Indoor dampness also appears to be associated with bronchitis and allergic rhinitis, but the evidence is either mixed allergic rhinitis or based on relatively few studies bronchitis. In agreement with the Institute of Medicinewe consider that there is insufficient evidence of a causal relationship with any of the health outcomes reviewed, although for asthma exacerbation we consider that there is almost enough evidence to meet the criteria of causality for dampness-related agents.
The evidence does not suggest that any one measurement of microbiological materials is demonstrably more specific or sensitive for assessing dampness-related exposure that is relevant to health effects. Thus, although it is plausible that heavy exposure to indoor mould or other microbial agents plays a causal role, this has not been established conclusively. Limitations of the approach The restricted scope of this review resulted in a number of limitations.
The method used to evaluate the evidence was largely non-quantitative; thus, all the available tools for summarizing the scientific literature could not be used. Furthermore, the conclusions of this review were derived primarily from findings based on qualitative measures of dampness-related factors. It is thus difficult to link the conclusions to specific exposures.
It is also likely that publication bias influenced the results, inflating the association between risk factors and health effects. Formal application of statistical methods for assessing bias was beyond the scope of this review. We did not search for unpublished findings, which would have decreased publication bias. The conclusions drawn from this review should thus be considered provisional until a more thorough consideration of all the available findings is possible.
It is recommended that the evidence for publication bias be addressed in a future review, with updated, quantitative summary estimates of risk. Clinical aspects of health effects This section focuses on studies involving human volunteers or experimental animals exposed in controlled circumstances, occupational groups or clinically. Most of these studies are based on small groups of individuals, but both the exposure and the clinical outcomes are characterized better than they are in the epidemiological studies.
Since then, their effects, particularly in relation to infection and cancer, have been investigated extensively. The research has focused almost entirely on orally or intravenously administered glucans, however, and few studies have been conducted of experimental exposure of humans to mould or glucans; nevertheless, a series of studies was performed with healthy volunteers by Rylander and colleagues in Sweden.
In contrast, no volume changes were observed after instillation of a solution of A. Experimental inhalation by healthy non-allergic people of A. In another study in Denmark, with double-blind, placebo-controlled exposure of people who had previously experienced building-related symptoms after exposure to spores from two different moulds, no clinical effects were observed Meyer et al.
An intriguing lack of increase in blood neutrophils on the days of exposure to mould, as compared with the normal diurnal increase after placebo, might have been due to neutrophil extravasation elsewhere in the body.
This concentration is substantially higher than those measured in buildings. Unfortunately, all the studies performed so far have been small and had insufficient statistical power to detect weak clinical effects.
Larger organisms, such as cockroaches, also inhabit damp spaces and may be responsible for some of the health problems attributed to these spaces and are addressed in the previously cited IOM reports. Studies of such microbial infections as tinea pedis athlete's foot that are associated with moisture but not the damp indoor conditions addressed in this report are excluded.
An extensive literature examines the influence on occupants' health of various agents found indoors—such as pesticides Lewis,nitrogen dioxide NO2 from gas appliances Neas et al. EPA, —or characteristics of indoor environments, including ventilation rate, temperature, and the use of circulated air and sealing measures to improve energy efficiency Engvall et al.
When reading this chapter, one should remember that many of the health effects attributed to the presence of mold or other dampness-related agents in the papers cited here have also been attributed to other factors. Not all papers that address damp indoor spaces control for those other factors, just as dampness-related agents are not always examined as possible factors in studies of the health effects of indoor spaces.
This weakness in the literature underlines the importance of the committee's recommendations for research on improved methods of exposure assessment.
Indoor environments are complex.
They subject occupants to multiple exposures that may interact physically or chemically with one another and with the other characteristics of the environment, such as humidity, temperature, and ventilation. Synergistic effects—interactions among agents that result in combined effects greater than the sums of the individual effects—may take place. Information on the combined effects of multiple factors and on synergist effects among agents is cited wherever possible.
However, as was noted in Clearing the Air, little information is available on this topic and it remains one of active research interest. Finally, some factors may influence people's exposure to indoor agents, their ability to respond to circumstances in which indoor exposure may increase the risk of adverse health outcomes, and their health in general.
Notable among those is socioeconomic status SES. Low SES may be a contributory or independent factor in some of the health outcomes addressed below, affecting their incidence of severity. Thus, when the committee draws conclusions about the association between damp indoor environments and health outcomes, it is not imposing the assumption—and readers should not presume—that these outcomes are necessarily associated with exposure to a specific microbial agent or to microbial agents in general.
When an association between a particular indoor dampness-related agent and a particular health outcome is addressed, it is specified in the text. However, even in those cases, it is likely that people are being exposed to multiple agents.
The following sections draw conclusions about the state of the scientific literature regarding association of health outcomes with two circumstances: As noted in Chapter 2the term dampness has been applied to a variety of moisture problems in buildings that include high relative humidity, condensation, and signs of excess moisture or microbial growth.
Most of the studies considered by the committee did not specify which microbial agents were present in the buildings occupied by subjects, and this likely varied between and even within study populations. The conclusions presented here qualify the term mold with quotation marks to indicate the uncertainty regarding the agents that may be involved. To fulfill their charge to evaluate the effect of damp indoor spaces on health, the committee conducted a review of epidemiologic studies.
The committee began their evaluation presuming neither the presence nor the absence of association. They sought to understand the strengths and limitations of the available evidence. These judgments have both quantitative and qualitative aspects. They reflect the nature of the exposures, health outcomes, and populations exposed; the characteristics of the evidence examined; and the approach taken by the study's authors to evaluate this evidence. Because of the great differences among the studies reviewed, the committee concluded it was inappropriate to use quantitative summary techniques such as meta-analysis.
Instead, as detailed in Chapter 1the committee summarized their judgment of the association between dampness or mold and particular health outcomes by using a common format to categorize the strength of the scientific evidence.
Fungi and other microbial agents are omnipresent in the environment, and the committee restricted its evaluation to circumstances that could be reasonably associated with damp indoor environments. Studies regarding homes, schools, and office buildings were considered; such other indoor environments as barns, silos, and factories—which may subject people to high occupational exposures to organic dusts and other microbial contaminants—were not.
The studies examined in this report primarily addressed dampness or mold in the home, reflecting the focus of researchers working in this field. A small number of studies of office or school environments were also evaluated. As detailed in Chapters 2 and 3many of the studies use reports of current or past signs of dampness and mold or general measures of it as a proxy for the agents of interest. A few have considered dampness as a risk factor separate from the presence of microbial agents indoors.
There are thought to be more than one million species of fungi, but humans are routinely exposed to only about IOM,and fewer than 50 are commonly identified and described in epidemiologic studies of indoor environments Asero and Bottazzi, Many health studies that evaluate the presence of mold do not formally identify species.
From a practical standpoint, that means that fungi—perhaps several species—are grouped with fungus-like bacteria such as thermophilic actinomycetes when the health consequences of microbiologic agents are being investigated. Epidemiologic studies that examine particular mold species or strains often fail to factor or minimize the possible influence of other mold species and bacteria and other agents associated with damp indoor environments.
Only a handful of researchers have explicitly examined chemical emissions from water-damaged materials. Their studies are discussed in Chapter 2. Clinical studies and case reports are additional sources of information on some health outcomes, but they are often limited by the small number of subjects examined. Clinical studies may involve exposure scenarios such as intentional installation that are not encountered outside the laboratory, and case reports often address unusual or unusually high potential exposures that are not representative of those experienced in homes, schools, or office buildings.
Some clinical studies and case reports are cited below; their results were considered by the committee with the understanding of their inherent limitations. Anecdotal reports of health problems attributed to mold indoors often dominate mass-media attention, but they are not a source of reliable information.
Good epidemiologic and clinical practice in investigations of potential environmental health problems requires—to the extent possible—the evaluation of all suspect environmental agents, valid measures of exposures and health outcomes, and thorough consideration of alternative explanations for observed signs, symptoms, and diseases.
Those criteria can be difficult to completely fulfill in scientific studies, and they are seldom met in outlets where information is not subject to rigorous scientific standards. Epidemiologists most commonly use questionnaires to collect information about symptoms, signs, and diseases. Exposures are often characterized through self-reports or expert-reports of the presence of dampness or visible mold. While self-reports are often the only way to gather information from large numbers of subjects in a cost-efficient manner, they have disadvantages that must be considered when evaluating studies that use them.
A self-report of dampness or visible mold, for example, may indicate rather a wide range of potential exposures: Except in cases where studies carefully separate dampness-related exposures or where specific biomarkers of exposure exist, it can be difficult to identify the responsible agent and even then the identification of the agent may be problematic. It is not always possible to determine whether a specific health outcome examined in a study is caused by an allergic reaction versus an infectious agent, an irritant stimulus, a toxic agent, or some other cause.
The clinical literature and to a lesser extent, toxicological studies, inform the interpretation of some epidemiological findings—especially those studies that are carried out under carefully controlled conditions. However, confident attribution of an outcome to a particular pathological mechanism is often limited by the observational rather than experimental nature of epidemiological studies and more than one mechanism may be responsible for the results in a particular study.
Studies reviewed by the committee examined populations from across the United States and numerous foreign countries including Canada, Australia, New Zealand, and the nations of Europe. Differences in such factors as climate, predominant mycoflora, building practices, the genetic make up of subjects, and cultural traditions may affect results.
Despite these limitations, epidemiological studies provide useful information for studying patterns of disease in populations and drawing conclusions about possible environmental influences.
Clinical measures are sometimes used in smaller-scale studies. For respiratory disease outcomes, these include lung-function testing based on spirometry or peak expiratory flow measures. Challenge testing with inhalation of methacholine, histamine, or other substances designed to induce bronchospasm in susceptible people has been used to measure the extent of bronchial hyperresponsiveness in clinical settings and epidemiologic studies.
The thorax has been imaged radiographically with chest x-rays and computed tomographic CT scans to evaluate individual patients in clinical studies. Lung biopsy may be indicated to confirm or rule out the diagnosis of particular diseases, such as hypersensitivity pneumonitis. Direct objective means of measuring nasal function have not been widely applied to the evaluation of complaints related to damp indoor spaces.
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Similarly, objective clinical measures have not been widely used to investigate gastrointestinal, dermatologic, rheumatologic, or neurologic complaints. A variety of biologic markers of inflammation are increasingly being applied to measure the effects of exposure to dampness and dampness-related agents in indoor environments Purokivi et al.
A study suggests that stachylysin—a proteinaceous hemolysin—may be a useful indicator of human exposure to Stachybotrys chartarum Van Emon et al.
Immunologic markers that have been examined in relation to indoor environmental exposures include cytokines, other mediators of inflammation, and antibodies to mycotoxins measured in nasal lavage fluids and in serum. Exhaled nitric oxide NO is a biomarker of respiratory tract inflammation that is elevated in some inflammatory lung conditions but not in others Robbins et al.
Measurement of substances in induced sputum samples and exhaled-breath condensate samples has not yet been applied to dampness or mold in indoor spaces but might be used to investigate them Mutli et al.
Can damp and mould affect my health?
Variability in individual susceptibility as mediated by genetic risk factors is beginning to be explored by investigators. Chapter 3 addresses the use of biomarkers in exposure assessment. Although this report focuses on health effects associated with excessive indoor dampness, excessive dryness may also be a problem. Low indoor relative humidity conditions are more likely in winter when cold outdoor air, which is less able to hold moisture, is drawn indoors and warmed.
Health complaints associated with indoor dryness include skin irritation, drying of the lining mucous membranes of the nose, mouth, and throat, nosebleeds, eye irritation, sore throat, and minor respiratory difficulties Arundel et al. A study by Reinikainen and Jaakkola found that, in dry conditions, increasing the humidity level alleviated some of these symptoms.
Studies reviewed vary in which symptoms and sets of symptoms they examine. The committee identified numerous studies that examine either individual URT symptoms such as nasal congestion or sore throat or groups of symptoms.
Can damp and mould affect my health? - NHS
Rhinitis, an inflammatory condition that involves the nasal mucosa, constitutes one such group: Sinusitis symptoms are similar to those of the common cold; they result from the inflammation of the paranasal sinuses.
Ear and eye symptoms related to URT infections are sometimes grouped with them. Sinus disease related specifically to Aspergillus is discussed later in this chapter. Because these symptoms often occur together, the table includes papers that address several different outcomes. The investigation, which examined Swiss children 4—5 years old, reported associations between humidity in the home and colds odds ratio [OR], 2. The ORs for the association between visible mold in the home and colds, bronchitis, and sore throats were also greater than 1.
Koskinen and colleagues a studied adults in Finland and found that those who reported moisture in their homes were more likely to have common colds 1. A companion study of children in the same residences Koskinen et al. However, the number of observations was relatively small, and the confidence intervals were wide. An association was also found with allergic rhinitis and visible mold 1. No association was observed between allergic conjunctivitis and either exposure surrogate. The analyses controlled for parental education, smoking, presence of second-hand smoke, pets, wall-to-wall carpeting, place of residence farm, rural nonfarm, or urbanand type of residence apartment vs other building types.
The researchers, who were investigating the influence of building characteristics on URT symptom incidence, hypothesized that the health outcomes were the result of exposure to the emission of 2-ethylhexanol due to alkaline degradation of octylphthalates in floor materials. The concentrations of total and viable molds and bacteria were low in the buildings evaluated in the study. A study of 4, children by Brunekreef et al. Some other studies reviewed by the committee examined less common symptoms or focused on particular dampness-related agents.
Subjects in moldy environments sometimes report an impaired sense of smell Koskinen et al. The ability to smell can be tested and measured, but the method has not been applied in studies of dampness or mold in indoor environments, so interpretation of results is problematic. A study showed an association between nasal polyposis and skin reactivity to Candida albicans in a study of 15 patients but did not specifically examine whether the exposure had indoor sources Asero and Bottazzi, Conclusions Several epidemiologic studies address the association between one or more URT symptoms—nasal congestion, sneezing, runny or itchy nose, and throat irritation—and indoor dampness or microbial contamination.
Studies are uniform in showing an increased risk of those symptoms; some, although not all, of the studies report statistically significant associations. The committee did not conduct an empirical investigation of the possible effect of publication or respondent bias; as indicated in Chapter 1it does not believe either to be the determining factor in the results. It concludes as follows: There is sufficient evidence of an association between exposure to a damp indoor environment and upper respiratory tract symptoms.
Lower Respiratory Tract Effects The major passages and structures of the lower respiratory tract LRT include the windpipe trachea and within the lungs, the bronchi, bronchioles, and alveoli. Although a number of LRT symptoms are reported when people are exposed to agents or particular environmental conditions in the home and other indoor spaces, limitations of study design sometimes preclude conclusions to be drawn regarding whether symptoms reported by participants indicate of the presence of defined disease entities.
LRT symptoms include cough with or without production of phlegm, wheeze, chest tightness, and shortness of breath dyspnea. Cough Cough can be triggered by a variety of means, including exposure to allergens or irritants.
It may either be a nonspecific complaint or be associated with a clinical syndrome. Overview of the Evidence Among the more recent studies reviewed in Table is a effort by Belanger and colleagues that prospectively examined persistent cough and wheeze in a cohort of infants up to 1 year old who had at least one sibling with physician-diagnosed asthma.
Telephone interviews were used to ascertain symptoms and home characteristics; indoor allergens house dust mites, cockroaches, cats, and dogsairborne fungal spores, and NO2 were measured.
In models that controlled for allergen concentrations, the presence of a gas or wood stove, maternal education, ethnicity, the sex of the child, and smoking in the home, measured mold or mildew was associated with persistent cough both in infants whose mothers had asthma 1. A study of the same cohort by Gent et al. The authors concluded that susceptible infants in homes with high Penicillium were at greater risk for cough but noted that the study was limited by the fact that a single airborne sample was used to represent exposure and that samples were taken at different times of the year and some molds exhibit seasonality.
However, no relationship was found for mold or water damage alone or for nocturnal cough. The Engvall et al. Their analyses accounted for subject age, sex, current smoking, number of subjects per room, and type of ventilation.
Two large studies of children are included in Table Cough was associated with parent-reported basement flooding, water damage, or leaks in the preceding year 1. Those estimates were not adjusted for confounders, but the authors stated that analyses that adjusted for age, sex, race, parental education, presence of environmental tobacco smoke ETSpresence of gas appliances, and hobbies that generate airborne contaminants yielded similar results.
Questionnaires were also used by Brunekreef et al. Similar ORs were estimated for the relationship between cough and the presence of mold 2. Conclusions Despite the variations in methods used to collect information, studies report a remarkably consistent association between cough and damp indoor conditions. Statistically significant associations between cough and visible signs of dampness or mold have been described by a number of investigators, with ORs of 1. The committee concludes There is sufficient evidence of an association between exposure to a damp indoor environment and cough.
Wheeze Wheeze is a musical or whistling sound, typically accompanied by labored breathing, produced when a person exhales; it may be accompanied by a feeling of tightening in the chest. It is a subjective finding that may be a sign or symptom of asthma but can also occur in persons who are not considered to be asthmatic. Before the age of about 3 years, children may exhibit wheeze or other symptoms that are characteristic of asthma, but they might not exhibit persistent asthmatic symptoms or other related conditions, such as bronchial reactivity or allergy, later in life.
Wheeze in these children may thus signify a non-allergic inflammatory process. In adults and older children, wheeze in the presence of dampness or mold more likely signifies an allergic response, although high level exposure to microbial agents may trigger an irritant response. Several agents found indoors and several indoor characteristics have been associated with increased likelihood of wheeze, including high relative humidity, low temperatures, gas heating, and the presence of smokers Ross et al.
Overview of the Evidence Studies of wheeze that examined direct or indirect measures of the presence of dampness or mold are summarized in Table Many of the studies cited in the table also examined the LRT health outcomes reviewed above.
Among the others is the Zock et al. The researchers found increased ORs for the associations between self-reported wheeze apart from colds in the last year characterized as an asthma symptom in the study and home water damage in the last year 1.
The analyses controlled for sex, age, and smoking status. Data on four measures of household dampness were analyzed: Reported household water damage was associated with an OR greater than 1. The authors suggested that household water damage might be an indicator of poorer housing quality and thus a surrogate for lower SES, noting that they found a stronger nonadjusted risk of current wheezing among children in lower SES categories.
Alternatively, they proposed that household water damage might simply have been more easily recognized than other forms of household dampness by study participants. When data were separated by subjects' race, household water damage was associated with current wheezing among both blacks prevalence ratio, 3. Surveys of parents were used to obtain information on the children's health and home characteristics; questionnaire data and measurements of suspended particulate matter and sulfur dioxide SO2 were used to construct an outdoor air-pollution index score.
After adjustment for outdoor air pollution, sex, parental education, type of home heating system, ETS, and the presence of a physician-diagnosed allergy, home mold or dampness was found to be associated with wheezing 1.
When subjects were separated by allergic status, nonallergic children of nonallergic parents were found to be at increased risk for two or more respiratory symptoms in the presence of home mold or dampness 2. Conclusions Studies demonstrate a consistent association between wheeze and various indications of indoor dampness, although the association of wheeze with exposure to indoor allergens notably, house dust mite in damp environments somewhat complicates the evaluation.
Studies addressing infants and children and those addressing adolescents and adults yield similar relative risk estimates. The committee concludes on the basis of its review that There is sufficient evidence of an association between exposure to a damp indoor environment and wheeze. Shortness of breath Dyspnea Dyspnea is the medical term for shortness of breath. It is a common complaint in persons suffering from a variety of respiratory illnesses and can also be a symptom in persons suffering from cardiac disease.
Acute inhalation of high concentrations of endotoxin may also cause dyspnea Jagielo et al.
Overview of the Evidence Clinicians and some investigators routinely perform lung-function testing as an objective measure of respiratory physiology in persons with dyspnea. Results from the epidemiologic studies that address dyspnea are summarized in Table Conclusions Available studies consistently report an association between exposure to dampness or the presence of mold otherwise unspecified and dyspnea. However, the small number of studies lessens the confidence with which conclusions can be drawn.
Taken together, There is limited or suggestive evidence of an association between exposure to a damp indoor environment and episodes of dyspnea shortness of breath. There is inadequate or insufficient evidence to determine whether an association exists between the presence of mold or other agents in damp indoor environments and episodes of dyspnea shortness of breath. It is usually caused by infectious organisms, including viruses, bacteria, and, less often, fungi.
It may also be caused by the inhalation of irritant substances. The inflammatory process that is common to the various etiologies of sinusitis leads to the presence of increased amounts of mucus and mucosal edema that prevent drainage of mucus through the ostia of the sinuses.
This obstructive process helps to cause or perpetuate microbial infection of the sinuses. Sinusitis can be an acute process that resolves spontaneously, can lead to a serious infection of the soft tissues surrounding the sinuses, and can become chronic and result in mucosal thickening and nasal polyps. The immune status of the patient helps to determine the course of the disease. Signs and symptoms of sinusitis are similar to those of allergic rhinitis and viral URT infections, and this can make diagnosis difficult.
Overview of the Evidence Fungal sinusitis can present in a variety of ways Schubert, The clinical syndromes that result from the presence of fungi in the paranasal sinuses include acute invasive fungal sinusitis, chronic invasive fungal sinusitis, mycetoma, and allergic fungal sinusitis. Fungi are commonly isolated from the nasal secretions of patients with chronic rhinosinusitis and from healthy people.
The presence of the fungi is indicative of colonization or noninvasive infection in most cases. Some 33 genera of fungi were isolated, with a mean of 3. Persons with chronic rhinosinusitis had eosinophilic mucin, which was not present in the normal control subjects. The presence of such allergic mucin is characteristic of the disorder termed allergic fungal rhinosinusitis AFS. Marple states that fungal exposure alone is thought to be insufficient to initiate AFS and that instead it is a multifactorial event that results from exposure to specific fungi, an IgE-mediated atopy, specific T-cell HLA receptor expression, and aberration of local mucosal defense mechanisms.
Invasive fungal sinusitis almost always occurs in persons who are immunocompromised by diabetes, hematologic malignancies, or immunosuppressive treatments after transplantation or chronic glucocorticoid therapy Malani and Kaufman, It may present as an acute, fulminant process that ends in death.
If the host is immunocompetent, it is more likely to be a subacute disorder. Conclusions It is not known whether the organisms that cause the various clinical syndromes of fungal sinusitis come from the indoor or the outdoor environment.
The committee did not identify any studies that associated the condition specifically with damp or moldy indoor spaces. As noted above, fungal colonization is often found in the sinuses of both healthy persons and those who have sinusitis or nasal symptoms. Available information does not indicate that exposure to a damp indoor environment or the presence of agents associated with them places otherwise-healthy people at risk for the various forms of sinusitis.
Airflow Obstruction Overview of the Evidence Airflow obstruction can be easily measured with a spirometer and can be seen in the context of asthma, chronic obstructive pulmonary disease COPDand other lung disorders that are more uncommon and less clearly linked to environmental exposures. Relatively little research has examined whether indoor dampness-related agents are associated with changes in FEV1 or FEV1: FVC, 3 the most reliable measures of obstructed airflow.
FVC ratio remained almost unchanged. An association between a reduction in FEF25—75 4 and living in a damp or mold-contaminated home was identified in one study in children Brunekreef et al. Such substances include common air pollutants, such as sulfur dioxide and ozone, and inhaled allergens Tilles and Bardana, The excessive responsiveness presents as cough and wheeze.
Bronchial hyperresponsiveness is seen not only in persons with asthma and other chronic inflammatory diseases of the airways but also in persons with allergic rhinitis and in many otherwise healthy people O'Byrne and Inman, Measurement of BHR is an important research tool in epidemiologic studies and clinical evaluations.
BHR has been associated with exposure to organic dust in occupational environments Carvalheiro et al. Conclusions Airflow obstruction is a prominent clinical finding of symptom exacerbation in people with asthma or COPD.
The following conclusions apply to persons who do not suffer from those diseases, which are addressed separately in this chapter: