| 1. |
- Walldén, Jakob, 1968-
(författare)
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The influence of opioids on gastric function : experimental and clinical studies
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Efter operation och anestesi får patienter ofta en negativ påverkan på magsäck och tarmar. Illamående och kräkningar är ett stort problem och många har svårt att komma igång med intag av föda och normal tarmfunktion då magsäcken och tarmarna ”står stilla”. Flera faktorer bidrar- bl.a. smärtan, det kirurgiska traumat och de läkemedel vi ger i samband med anestesin. Av de senare är opioider, d.v.s morfin och morfinliknande läkemedel, starkt bidragande. I detta avhandlings- arbete har opioiders effekter på magsäckens motilitet studerats. Med ett absorptionstest (paracetamolmetoden) studerades hos frivilliga hur opioiden remifentanil påverkar magsäckstömning och om kroppspositionen har betydelse för tömningshastigheten ut i tarmen. Remifentanil fördröjde magsäcks-tömningen och under pågående opioid behandling hade kroppspositionen ingen större betydelse, vilket det däremot hade under kontrollförsöken. Med samma metod jämförde vi hos patienter två anestesimetoder och studerade magsäcks-tömning direkt efter en operation. Ingen skillnad kunde påvisas mellan en opioidbaserad och en opioidfri anestesi, men inom respektive grupp var det en stor variation i magsäckstömning mellan individerna. Med en barostat studerades tonus i övre delen av magsäcken. Hos hälften av de frivilliga orsakade remifentanil en ökning av tonus och hos den andra hälften en minskning av tonus. Vidare undersöktes hos en grupp patienter opioiden fentanyls påverkan på den elektriska aktiviteten i magsäcken. Med en elekroga-strograf (EGG) registrerades de långsamma elektriska vågor som koordinerar muskelrörelserna i magsäcken. Hos hälften av de undersökta påverkades aktiviteten av fentanyl med en sänkt vågfrekvens eller upphörande av vågor, medan aktiviteten var opåverkad hos den övriga hälften. För att finna en förklaring till variationen gjordes genetiska analyser av genen för opioidreceptorn hos de undersökta i barostat och EGG studierna. Variationer i genomet, s.k. polymorfism, var inte associerad till utfallen i studierna. Studierna har visat på att opioider har en uttalad effekt på magsäckens motilitet och att den varierar kraftigt mellan individer. Polymorfism i genen för opioid- receptorn förklarade inte skillnaden mellan individer. Direkt efter operation bidrar sannolikt andra faktorer än anestesimetod till det variabla utfallet i magsäckstömning.
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| 2. |
- Ahlsson, Anders, 1962-
(författare)
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Atrial fibrillation in cardiac surgery
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Atrial fibrillation (AF) is the most common arrhythmia seen in clinical practice. In cardiac surgery, one-third of the patients experience episodes of AF during the first postoperative days (postoperative AF), and patients with preoperative AF (concomitant AF) can be offered ablation procedures in conjunction with surgery, in order to restore ordinary sinus rhythm (SR). The aim of this work was to study the relation between postoperative AF and inflammation; the long-term consequences of postoperative AF on mortality and late arrhythmia; and atrial function after concomitant surgical ablation for AF. In 524 open-heart surgery patients, C-reactive protein (CRP) serum concentrations were measured before and on the third day after surgery. There was no correlation between levels of CRP and the development of postoperative AF. All 1,419 patients with no history of AF, undergoing primary aortocoronary bypass surgery (CABG) in the years 1997–2000 were followed up after 8.0 years. The mortality rate was 191 deaths/1,000 patients (19.1%) in patients with no AF and 140 deaths/419 patients (33.4%) in patients with postoperative AF. Postoperative AF was an age-independent risk factor for late mortality, with a hazard ratio (HR) of 1.56 (95% CI 1.23–1.98). Postoperative AF patients had a more than doubled risk of death due to cerebral ischaemia, myocardial infarction, sudden death, and heart failure compared with patients without AF. All 571 consecutive patients undergoing primary CABG during the years 1999–2000 were followed-up after 6 years. Questionnaires were obtained from 91.6% of surviving patients and an electrocardiogram (ECG) from 88.3% of all patients. In postoperative AF patients, 14.1% had AF at follow-up, compared with 2.8% of patients with no AF at surgery (p<.001). An episode of postoperative AF was found to be an independent risk factor for development of late AF, with an adjusted risk ratio (RR) of 3.11 (95% CI 1.41–6.87). Epicardial microwave ablation was performed in 20 open-heart surgery patients with concomitant AF. Transthoracic echocardiography was performed preoperatively and at 6 months postoperatively. At 12 months postoperatively 14/19 patients (74%) were in SR with no anti-arrhythmic drugs. All patients in SR had preserved left and right atrial filling waves (A-waves) and Tissue velocity echocardiography (TVE) showed preserved atrial wall velocities and atrial strain. In conclusion, postoperative AF is an independent risk factor for late mortality and later development of AF. There is no correlation between the inflammatory marker CRP and postoperative AF. Epicardial microwave ablation of concomitant AF results in SR in the majority of patients and seems to preserve atrial mechanical function.
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| 3. |
- Allvin, Renée, 1956-
(författare)
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Postoperative recovery : development of a multi-dimensional questionnaire for assessment of Recovery
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis aims to present a multi-dimensional instrument for self-assessment of progress in postoperative recovery. The author employs different research paradigms and methodologies to achieve this aim. Walker and Avant’s approach to concept analysis was used to examine the basic elements of postoperative recovery (Study I). The analysis identified different recovery dimensions and developed a theoretical definition showing postoperative recovery to be an energy-requiring process of returning to normality and wholeness, defined by comparative standards. Fourteen patients and 28 staff members participated in individual and focus group interviews aimed at describing patient and staff experiences of patient recovery (Study II). The essence of the postoperative recovery process was described as a desire to decrease unpleasant physical symptoms, reach a level of emotional wellbeing, regain functions, and re-establish activities. In Study III, 5 dimensions and 19 items were identified as a part of the operationalization process of the concept postoperative recovery. Fifteen staff members and 16 patients participated in the evaluation of content validity. On average, 85% of the participants considered the items as essential to the recovery process. In a test run of the questionnaire, 14 of 15 patients considered the questionnaire to be easy to understand and easy to complete. Twenty-five patients participated in the evaluation of intra-patient reliability. Percentage agreement (PA), systematic disagreement (RP, RC), and individual variability (RV) between the two assessments were calculated. PA measures ranged from 72% to 100%. The observed disagreement could be explained mainly by systematic disagreement. In total, 158 patients participated in the evaluation of construct validity, the ability to discriminate between groups, and the investigation of important item variables (Study IV). A rank-based statistical method for evaluation of paired, ordered categorical data from rating scales was used to evaluate consistency between the assessments of the Postoperative Recovery Profile (PRP) questionnaire and a global recovery scale. The number of months needed by participants to be regarded as fully recovered was studied by means of recovery profiles displayed by the cumulative proportion of recovered participants over time. A ranking list based on the participant’s appraisal of the five most important item variables in the PRP questionnaire was compiled to illustrate the rank ordering of the items. In comparing the assessments from the PRP questionnaire and the global recovery scale, 7.6% of all possible pairs were disordered. Twelve months after discharge 73% in the orthopaedic group were regarded as fully recovered, compared to 51% of the participants in the abdominal group (95% CI: 6% to 40%). The pain variable appeared among the top five most important items on eight measurement occasions, of eight possible, in both study groups. In conclusion, the PRP questionnaire was developed and support was given for validity and reliability. The questionnaire enables one to evaluate progress in postoperative recovery.
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| 4. |
- Andersson, Gunnel, 1958-
(författare)
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Urinary incontinence : prevalence, treatment seeking behaviour, experiences, and perceptions among persons with and without urinary leakage
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim of this thesis is to describe urinary incontinence (UI) from a population perspective and to describe experiences and perceptions of UI from an individual perspective. This includes assessing the prevalence of urinary incontinence as well as describing treatment seeking and experiences of living with UI. A secondary aim was to describe the perception of UI among cultures other than the Swedish mainstream, exemplified in this case by Syrian women living in Sweden. Both quantitative and qualitative methods were used, including questionnaires and interviews. Studies I and II were quantitative studies based on a population-based study. Together with a postal survey on general health and living conditions “Life & Health”, a questionnaire on urinary incontinence was sent out to 15 360 randomly-selected residents aged 18-79 in Orebro County, Sweden. In Study I, UI was found to affect 19%. The majority of the respondents experienced minor problems, and only 18% of those reporting UI wanted treatment. However, there was also a group who reported severe problems, but despite this 42% of them did not want treatment. Study II investigated why people with UI refrain from seeking care and treatment. It was found that the desire for treatment was regulated by the frequency of UI, being restricted from participating in various activities, the degree of inconvenience, and the type of UI. Studies III and IV were both qualitative interview studies, describing older women’s experiences of living with UI (Study III) and Syrian women’s perceptions of UI (Study IV). There were similarities between the results of these two studies; the women described UI as a normal and expected problem, and they knew that the district nurse could prescribe incontinence protections and that treatments existed. In both studies, the women expressed difficulties in making contact with the health care service, while the women who did not speak Swedish (Study IV) also had difficulties due to different communication problems. In conclusion, it is important that health care resources are optimized to identify and meet the needs of those who experience major problems with UI, and that there is awareness of the communication difficulties that can be present in meeting with people who speak other languages. However it is also important not to medicalize those who experience minor problems and who have the desire to manage on their own.
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| 5. |
- Anderzén-Carlsson, Agneta, 1966-
(författare)
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Children with cancer : focusing on their fear and on how their fear is handled
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Various fears in children with cancer have previously been identified as a result of studying e.g. symptom experiences, distress and uncertainty within this population. Studies of the meaning the children give to their fear, as well as the handling of their fear seem to be sparse, however. Also, fear has not been an exclusive focus in previous studies. Professionals in clinical practice have pointed to the need for such research, which has prompted the present research work. The overall aim of this thesis was therefore twofold; firstly, the aim was to elucidate fear in children and adolescents with cancer in order to gain an understanding from the perspective of adolescents and parents. Secondly, it was to elucidate parents’ and professionals’ handling of the fear. This in order to gain a deeper understanding of what performances and manners the children and adolescents can face when being fearful. A qualitative descriptive design was adopted in the five included studies. The methods used in the data analysis were phenomenological hermeneutical method (studies I–III) and qualitative content analysis (studies IV–V). In study I six adolescent girls, aged 14–16 years, with experiences of various cancer diagnoses, but now declared fit, were interviewed. The results reveal that they experience their fear as embodied, which in the comprehensive understanding of the results was interpreted as a threat to their personal self, their whole existence. Their fear was seen as a holistic intertwined experience, including fear related to the physical body and to the social self. Also, existential fear was described. Their described experience was interpreted as suffering. Studies II and III share the same data. Fifteen parents of children at various ages with various cancer diagnoses were interviewed in focus groups about their experience of their child’s fear. In study II the result reveals how the parents experienced and understood their child’s fear. The fear was described as a multidimensional phenomenon, which was not always easy to identify. It was contrasted to feelings of unease and to absence of fear. In the comprehensive understanding the fear was interpreted as a suffering, as that was regarded to be what was the common meaning in the narratives. The suffering was interpreted as an ethical demand to the parents to take action. In study III the parents described their actions, i.e. they described how they dealt with the fear. Their actions were described as acting in the best interests of the child, which included striving to make the child feel secure and experience wellbeing, up to a certain point. However, after this point the parents used their parental authority to maintain the child’s physical health rather than trying to prevent or relieve the child’s fear. In the comprehensive understanding the parents’ handling of their child’s fear was interpreted as revealing mercy and as being synonymous with meeting the ethical demand put on them. In study IV ten experienced nurses and physicians were individually interviewed about how they handled fear in children with cancer. The result reveals that the existential issues were dealt with within the relationship with the child, on a sliding scale between closeness and distance, and that the fear related to medical procedures occurred on a continuum between support and lack of support. The various actions involved, and the manner in which these actions were performed, was described. In the observational study (study V) eleven parents and their children as well as eleven health professionals participated. They were observed at children’s routine visits at the outpatient clinic. The aim was to study the interactions related to fear. The result reveals that when children were fearful they expressed this both verbally and non-verbally. The parents’ and professionals’ actions and interactions in these situations were found to be characterized by recognition of the fear or lack of attention to the fear. The findings can contribute to a broadened knowledge on fear in children and adolescents with cancer. Awareness and understanding of the meaning adolescents give to their fear, and furthermore, of the parents’ experience and understanding of their child’s fear can provide tools for interacting with these groups. The findings on how fear is dealt with by the ones children have claimed as important sources for support, can give insights into what the child may face when being fearful. These insights can form the basis for individual, as well as collegial, reflections on what is done when children face fear, how fear is handled on an everyday basis and why it is handled in this way. Such reflections could lead to an ethical awareness of handling fear in children with cancer.
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| 6. |
- Andrén, Ove, 1963-
(författare)
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Natural history and prognostic factors in localized prostate cancer
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The natural history of localized prostate cancer is not fully understood. In most patients the tumor will never progress to a lethal disease, while a subset of patients will ultimately die of the disease. Efficient tools to separate indolent from lethal disease is currently lacking which means that many patients will be offered treatment without any benefit, but still be at risk of experiencing treatment related side effects. The aims of these studies were to get more insight into the natural history of untreated localized prostate cancer, to assess the prognostic value of established clinical parameters such as Gleason score, nuclear grade and tumor volume and, moreover, some new prognostic markers Ki-67, AMACR and MUC-1. We also aimed to study time trends in the detection of incidental tumors in Sweden. Patients with localized disease (n=223) and no initial treatment were followed for 21 years. Most patients had a favorable outcome. However, a subset of patients developed lethal disease even beyond 15 years of follow-up and these patients define the group that may benefit most from treatment with curative intent. Patients with poorly differentiated tumors experienced a 9 time higher risk of dying in prostate cancer. The studies on prognostic markers are based on a cohort of patients (n=253) with incidental prostate cancer detected by transurethral resection for presumed benign hyperplasia. All patients were left without initial treatment. Gleason grade, nuclear grade and tumor volume turned all out to be independent prognostic factors. MUC-1, AMACR and Ki-67 also carried prognostic information. However, after adjustment for Gleason grade, nuclear grade and tumor volume only MUC-1 and AMACR remained as statistically significant prognostic factors. When tested for sensitivity and specificity they all failed and, consequently, they seem to be of less value in daily practice for cancelling an individual patient regarding the choice of treatment. Time trends in incidental prostate tumors in Sweden were analyzed in a cohort of patients with prostate tumors detected by transurethral resection (TUR-P). Through linkage of the national registration number (NRN) with several registers, e.g. the Swedish Cancer Registry, the National Inpatient registry and the Cause of Death Registry we identified, during the period 1970 through 2003, in total 23288 patients with incidental prostate cancer, who constituted the study group. As comparison group we choose all patients diagnosed with prostate cancer between 1970-2003 excluding those with incidental cancer, in total 112204 patients. Our result confirms earlier findings that there has been a dramatic change over time in incidence of incidental prostate cancers in Sweden, which parallels the introduction of prostate specific antigen. We also found that the cumulative incidence of prostate cancer death is high in the incidental group, opposing earlier findings that incidental tumours are a non-lethal disease.
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| 7. |
- Berglund, Carolina, 1980-
(författare)
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Molecular epidemiology of methicillin-resistant staphylococcus aureus : epidemiological aspects of MRSA and the dissemination in the community and in hospitals
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Methicillin-resistenta Staphylococcus aureus (MRSA) som bär på genen mecA, har förekommit och spridit sig över hela världen, främst i sjukhusmiljö, och orsakat utbrott av vårdrelaterade (så kallade nosokomiala) infektioner. Dessa infektioner kan inte behandlas med stafylokock-penicilliner och MRSA-bakterierna är ofta resistenta även mot flera andra grupper av antibiotika vilket medför att infektionerna ofta är påtagligt svårbehandlade. Under senare år har emellertid allt fler fall beskrivits av samhällsförvärvad MRSA infektion, det vill säga uppträdande av MRSA hos personer som tidigare ej har haft kontakt med sjukhusvård eller behandlats med antibiotika. Det har länge varit oklart om de samhällsförvärvade MRSA [community-acquired (CA-MRSA)] representerar spridning av bakterier från sjukhusmiljön ut till samhället eller om dessa MRSA är spontant uppträdande. Många av dessa stammar har dessutom visat sig bära på sjukdomsrelaterade gener som vanligen inte återfinns hos S. aureus, t.ex. Panton Valentine leukocidin (PVL) som associeras med hudinfektioner och allvarlig lunginflammation med hög dödlighet hos unga och annars friska individer. Denna avhandling beskriver den molekylära epidemiologin hos MRSA med fokus på samhällsförvärvade MRSA som utgjorde mer än hälften av samtliga fall av MRSA i Örebro län och som dessutom ofta producerade PVL toxinet, vars funktion vidare analyserades i detalj. Undersökning av ursprung och släktskap hos samtliga MRSA som isolerats i Örebro län, samt karaktärisering av det genetiskt element som kallas staphylococcal cassette chromosome mec (SCCmec) vilket innehåller genen mecA och ibland även andra resistensgener, visade att CA-MRSA inte är relaterade till de nosokomiala MRSA, och att dessa har uppstått oberoende av varandra. Flertalet MRSA visade sig dessutom bära på SCCmec, och resistensmekanismer, som tidigare inte beskrivits. Troligen har dessa MRSA uppstått genom ett genetiskt utbyte av SCCmec mellan methicillin-resistenta koagulas-negativa stafylokocker (MR-KNS), som utgör huvudparten av normalfloran på huden, och methicillin-känsliga S. aureus som därvid erhåller genen mecA och resistensmekanismer mot samtliga stafylokockantibiotika. I den här avhandlingen framläggs bevis för att ett sådant genetiskt utbyte har skett på Barnkliniken på Universitetssjukhuset i Örebro i slutet på 1990-talet, vilket resulterade i uppkomsten av en ny klon av MRSA som därefter orsakade ett allvarligt utbrott. Kartläggning av DNA-sekvensen hos flertalet unika SCCmec från svenska MRSA gav dessutom en bättre förståelse för hur resistens uppkommer och sprider sig, samt mekanismerna bakom detta. Dessa nya kunskaper kan bidra till en förbättrad diagnostik av MRSA. Detta är framför allt av stor betydelse eftersom nya effektiva kloner av MRSA verkar kunna uppstå ute i samhället med potential att orsaka svårbehandlade infektioner men även att sprida sig bland den friska befolkningen.
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| 8. |
- Björk, Tabita
(författare)
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Measuring eating disorder outcome : definitions, dropout and patients' perspectives
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Despite a plethora of research, there are serious limitations in our knowledge of outcome in eating disorders. Almost all studies have been compromised by the problem of treatment dropout or non-participation in follow-ups. There exists a lack of consensus in definitions of outcome and choice of outcome measures, and there is a dearth of studies focusing on how patients subjectively perceive recovery. The overall aim of this thesis was to address problems in measuring outcome after treatment for eating disorders, with an emphasis on methodological issues. Specific areas of investigation included non-participation in long-term follow-ups, the role of self-image in treatment dropout, outcome among patients who drop out, patients’ subjective perspectives of recovery, and the impact of different methods of measuring outcome. Method: Four quantitative studies (I, II, III and V) were conducted within the framework of a large Swedish multi-centre study of eating disorders, which adopted a prospective, longitudinal and naturalistic design. Study IV was a qualitative investigation encompassing interviews with former ex-patients who were considered recovered. Results: Study I suggested that the reasons for non-participation in research were mainly patient related (69%). Those declining further participation in follow-ups were reported significantly lower levels of obsession-compulsion and anxiety, while those not traceable reported significantly higher levels of hostility at admission. Study II suggested that patients who dropped out from treatment initially presented with less negative self-image and fewer psychological problems compared to those who remained in treatment. Low levels of self-blame discriminated dropouts from completers and remainers, and significantly predicted treatment dropout. Study III found no significant differences between dropouts and completers at follow-up, with the exception that dropouts were more dissatisfied with treatment. However, patterns of treatment response revealed that those who completed treatment made significantly greater changes in terms of reduced eating disorder symptoms, fewer psychological problems and a more positive self-image compared to dropouts. Study IV found that patients who had recovered from an eating disorder tended to describe other dimensions of outcome than those usually reported in follow-ups. Patients tended to view recovery in terms of being able to relate in a relaxed and accepting manner to food, their bodies, themselves as individuals, and their social environment. Some perceived recovery in terms of coping better with emotions, while others experienced themselves as healthier than people generally regarding food and weight. Study V applied some of the most frequently used outcome measures for eating disorders and found marked variations in the number of patients who could be considered in remission. Overall remission rates varied from 24.3% to 77.8%, depending on the outcome measure used. Discussion: The results suggest that non-participation and dropout are not unitary phenomena. There is also a need for greater consensus on how eating disorder outcome should be measured. This is necessary in order to make comparisons between different outcome studies meaningful, and to elucidate the overall picture of eating disorders outcome.
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| 9. |
- Böttiger, Anna, 1977-
(författare)
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Genetic variation in the folate receptor-alpha and methylenetetrahydrofolate reductase genes as determinants of plasma homocysteine concentrations
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Elevated total plasma homocysteine (tHcy) is a risk factor for cardiovascular disease and neurocognitive disease such as dementia. The B vitamins folate and B12 are the main de terminants of tHcy. tHcy concentration can also be affected by mutations in genes coding for receptors, enzymes and transporters important in the metabolism of Hcy. This thesis focuses on mutations in the genes for folate receptor-alpha and methylenetetrahydrofolate reductase (MTHFR) and the effect they have on tHcy concentrations. Six novel mutations in the gene for folate receptor-alpha were described in Paper I. Taken together they exist in a population with a prevalence of approximately 1% and thus are not unusual. There may be an association of –69dupA and –18C>T to tHcy but for the 25-bp deletion, –856C>T, –921T>C and –1043G>A there is probably no association to tHcy. Mutation screening was continued and four additional mutations, 1314G>A, 1816delC, 1841G>A and 1928C>T, were described in Paper II. The prevalences for the heterozygotes were between 0.5% and 13% in an elderly population. There was no significant difference in prevalence between the elderly subjects and patients with dementia. The 1816(–)-allele and the 1841A-allele were in complete linkage and the haplotype 1816(–)-1841A may possibly have a tHcy raising effect. The 1314G>A and 1928C>T mutations had no association to tHcy. The genotype prevalences and haplotype frequencies of the MTHFR 677C>T, 1298A>C and 1793G>A polymorphisms were determined in a population sample of Swedish children and adolescents (Paper III). The MTHFR 677T-allele was associated with increased tHcy concentrations in both children and adolescents. A small elevating effect of the 1298C-allele and a small lowering effect of the 1793A-allele could be shown. In an epidemiological sample of adults from the Canary Islands, Spain, data for serum folate and vitamin B12 were used for a broader study of the nutrigenetic impact on tHcy (Paper IV). The 677T-allele had a significant tHcy increasing effect in men but not in women. The 1298C-allele had a minor elevating effect on tHcy in men with the 677CT genotype. It was not possible to document any effect of the 1793A-allele on tHcy due to its low prevalence. A slightly superior explanatory power for the genetic impact was obtained using the MTHFR haplotypes in the analysis compared to the MTHFR 677C>T genotype-based approach in both the Swedish children and adolescents and in the Spanish adults. Therefore MTHFR haplotypes should be considered when analysing the impact of the MTHFR 677C>T, 1298A>C and 1793G>A polymorphisms on tHcy. Notwithstanding the large geographical distance between our study populations the haplotype composition is quite similar. The MTHFR 677T-allele is slightly more prevalent in Spain compared to Sweden but it has only an effect on tHcy in the Spanish men. Age, gender and factors linked to the ethnicity of the studied subjects, seem to be able to override the nutrigenetic impact of tHcy-raising genotypes or haplotypes in particular settings, such as in the Spanish women in our study. Gene-nutrient interactions on plasma tHcy levels thus may or may not exist in a certain population. The transferability of nutrigenetic findings may therefore be limited, and must be re-evaluated for each particular setting of age-gender-ethnicity.
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| 10. |
- Carlsson, Per-Inge, 1959-
(författare)
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Hearing impairment and deafness : genetic and environmental factors - interactions - consequences : a clinical audiological approach
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- OBJECTIVES - Hearing impairment (HI) can be due to genetic or environmental factors, e.g. noise. More than 50% of HI cases are thougt to be hereditary. HI can affect social participation in different ways. How serious these problems becomes depends on several factors, for example, the type of social environment the person lives in. The objective of the present study was to point out the importance of studying HI and deafness in a broad perspective, from the molecular - biological level to the psychological - social level and to evaluate how interactions of factors at several levels form the consequences, in a long-term perspective, to witch HI and deafness can lead. MATERIAL AND METHODS - Three different study populations have been used to study the four levels in this study: Papers I - III; 1200 noise-exposed workers (molecular and biological levels), Paper IV; 50 persons with HI since early childhood, with or without a family history of HI (FHHI)(biological, psychological and social level), and in Paper V; 600 persons with early onset of deafness in two counties with differently strong Deaf communities (psychological and social level). RESULTS - The molecular genetic studies (Papers I – III) showed that the combination of smoking and having a mutation in the protective antioxidant system revealed an additional risk for noise induced hearing loss. In Paper IV, only small differences was found between subjects with and without a FHHI. The results in Paper V indicated that differences in the social environment, in terms of the strength of the Deaf community, influence family factors such as marriages, divorces and the number of children born. CONCLUSIONS - Analysing complex issues such as HI and deafness from a medical audiological perspective requires a multi- level approach at several levels. The results indicate that interactions of factors at all four levels form the consequences, in a long-term perspective, to wich HI and deafness can lead. Furthermore, this multi-level approach - here called a clinical audiological approach - is essential when using the ICF framework in audiological rehabilitation/habilitation.
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