Lifetime prevalence of homelessness in housed people aged 55-79 years in England: its childhood correlates and association with mortality over 10 years of follow-up.

OBJECTIVES: Since 2010, the number of homeless people in the UK has increased, and homelessness in its different types has become a major public health problem. Housed older people with past experience of homelessness are an understudied population that can provide valuable insight into this problem. For this reason, we examined the lifetime prevalence of homelessness and its associations with childhood adversity and mortality in a national sample of older people. STUDY DESIGN: This is a longitudinal cohort study. METHODS: We studied 6649 housed individuals aged 55-79 years in 2007 from the English Longitudinal Study of Ageing (ELSA). We used logistic regression to model the association between adverse childhood experiences (ACE) and lifetime experience of homelessness (ever been homeless for ≥1 months) and Cox proportional hazards regression to model the prospective association between lifetime experience of homelessness and mortality. RESULTS: We identified 107 participants with lifetime experience of homelessness. We found a strong graded association between the number of ACE and lifetime experience of homelessness; participants with two ACE had 5.35 (95% confidence interval [CI]: 3.17-9.05) times greater odds of having experienced homelessness than those reporting none. Most ACE were individually associated with lifetime homelessness, but fewer remained so in the mutually adjusted model. Participants with lifetime experience of homelessness had 1.55 (95% CI: 1.01-2.37) times greater risk of mortality over a 10-year follow-up and after adjustment for covariates. CONCLUSIONS: Exposure to childhood adversity is associated with increased risk of experiencing homelessness. Older housed people with past experience of homelessness are at increased risk of mortality.

Accuracy of an automated system for tuberculosis detection on chest radiographs in high-risk screening.

SETTING: Tuberculosis (TB) screening programmes can be optimised by reducing the number of chest radiographs (CXRs) requiring interpretation by human experts. OBJECTIVE: To evaluate the performance of computerised detection software in triaging CXRs in a high-throughput digital mobile TB screening programme. DESIGN: A retrospective evaluation of the software was performed on a database of 38 961 postero-anterior CXRs from unique individuals seen between 2005 and 2010, 87 of whom were diagnosed with TB. The software generated a TB likelihood score for each CXR. This score was compared with a reference standard for notified active pulmonary TB using receiver operating characteristic (ROC) curve and localisation ROC (LROC) curve analyses. RESULTS: On ROC curve analysis, software specificity was 55.71% (95%CI 55.21-56.20) and negative predictive value was 99.98% (95%CI 99.95-99.99), at a sensitivity of 95%. The area under the ROC curve was 0.90 (95%CI 0.86-0.93). Results of the LROC curve analysis were similar. CONCLUSION: The software could identify more than half of the normal images in a TB screening setting while maintaining high sensitivity, and may therefore be used for triage.

Seasonality of urinary tract infections in the United Kingdom in different age groups: longitudinal analysis of The Health Improvement Network (THIN).

Evidence regarding the seasonality of urinary tract infection (UTI) consultations in primary care is conflicting and methodologically poor. To our knowledge, this is the first study to determine whether this seasonality exists in the UK, identify the peak months and describe seasonality by age. The monthly number of UTI consultations (N = 992 803) and nitrofurantoin and trimethoprim prescriptions (N = 1 719 416) during 2008-2015 was extracted from The Health Improvement Network (THIN), a large nationally representative UK dataset of electronic patient records. Negative binomial regression models were fitted to these data to investigate seasonal fluctuations by age group (14-17, 18-24, 25-45, 46-69, 70-84, 85+) and by sex, accounting for a change in the rate of UTI over the study period. A September to November peak in UTI consultation incidence was observed for ages 14-69. This seasonality progressively faded in older age groups and no seasonality was found in individuals aged 85+, in whom UTIs were most common. UTIs were rare in males but followed a similar seasonal pattern than in females. We show strong evidence of an autumnal seasonality for UTIs in individuals under 70 years of age and a lack of seasonality in the very old. These findings should provide helpful information when interpreting surveillance reports and the results of interventions against UTI.

Evidence for increasing severity of community-onset boils and abscesses in UK General Practice.

In England, hospital admissions for severe staphylococcal boils and abscesses trebled between 1989 and 2004. We investigated this trend using routine data from primary and secondary care. We used The Health Improvement Network (THIN), a large primary-care database and national data on hospital admissions from Hospital Episode Statistics (HES). Time trends in the incidence of primary-care consultations for boils and abscesses were estimated for 1995-2010. HES data were used to calculate age-standardized hospital admission rates for boils, abscesses and cellulitis. The incidence of boil or abscess was 450 [95% confidence interval (CI) 447-452] per 100 000 person-years and increased slightly over the study period (incidence rate ratio 1·005, 95% CI 1·004-1·007). The rate of repeat consultation for a boil or abscess increased from 66 (95% CI 59-73) per 100 000 person-years in 1995 to peak at 97 (95% CI 94-101) per 100 000 person-years in 2006, remaining stable thereafter. Hospital admissions for abscesses, carbuncles, furuncles and cellulitis almost doubled, from 123 admissions per 100 000 in 1998/1999 to 236 admissions per 100 000 in 2010/2011. Rising hospitalization and recurrence rates set against a background of stable community incidence suggests increased disease severity. Patients may be experiencing more severe and recurrent staphylococcal skin disease with limited treatment options.

Tuberculosis peer educators: personal experiences of working with socially excluded communities in London.

SETTING: Peer education is a relatively unexplored intervention for tuberculosis (TB) control, particularly among socially excluded communities. In London, peer educators are used to raise awareness of TB and promote uptake of radiological screening among people using homeless and/or drug and alcohol treatment services. OBJECTIVE: To understand the motivation and personal impact of being a peer educator on people with experience of anti-tuberculosis treatment, homelessness and addiction. DESIGN: In-depth semi-structured interviews with peer educators were recorded and transcribed, and then analysed using a grounded theory approach to identify themes. Reflexivity and thick description were used to support transparency of findings. RESULTS: Becoming a peer educator supports individuals in making sense of past experiences and renewing their sense of self. The role places value on personal experience and the communication approach this supports. The project environment is an important motivator, providing the peer with structure, social support and respect. CONCLUSION: Being a peer educator with experience of homelessness and addiction can be beneficial and empowering and help long-term recovery. Peers are an underused resource for strengthening TB control among socially excluded populations. There is a need for further research into the contribution of peers to TB control, including analyses of economic effectiveness.

Active case finding for pulmonary tuberculosis using mobile digital chest radiography: an observational study.

BACKGROUND: Mobile digital chest radiography (CXR) is used routinely to screen for pulmonary tuberculosis (PTB) in London among homeless populations, persons accessing drug treatment services and prisoners. OBJECTIVE: 1) To establish the sensitivity and specificity of mobile digital CXR, and 2) to test the hypothesis that actively identified cases have reduced odds of sputum smear positivity vs. those presenting passively to health care services from the same populations. METHODS: Sensitivity and specificity were calculated using a gold standard comparator of culture-confirmed cases of PTB reported to the national surveillance system within 90 days of screening. Logistic regression was used to determine whether actively detected cases had reduced odds of smear positivity compared to passively detected cases after adjustment for confounding. RESULTS: The intervention had a sensitivity of 81.8% (95%CI 64.5-93.0) and a specificity of 99.2% (95%CI 99.1-99.3). After adjusting for confounding, there was evidence that cases identified through screening were less likely to be smear-positive than passively identified cases (OR 0.34, 95%CI 0.14-0.85; likelihood ratio test P = 0.022). CONCLUSION: Digital CXR achieves a high level of sensitivity and specificity in an operational setting; targeted mobile radiographic screening can reduce the risk of onward transmission by identifying cases before they become infectious.

Panton-Valentine leukocidin associated staphylococcal disease: a cross-sectional study at a London hospital, England.

Recently, there has been international concern at the rapid emergence of highly pathogenic strains of Staphylococcus aureus associated with a toxin called Panton-Valentine leukocidin (PVL). In the UK, these strains are considered to be rare and mainly severe. We estimate the proportion of staphylococcal infections that are caused by strains containing the PVL genes, and describe risk factors for these infections. Three hundred and ninety consecutive S. aureus clinical isolates, submitted for routine diagnostic purposes were screened for PVL genes. Risk factors for infection were identified from the patient medical record. 9.7% (95% CI 7.0-13.1%) of clinical isolates and 20.8% of skin and soft tissue specimens contained the genes for PVL. Methicillin-resistant S. aureus with PVL was rare (0.8% of all isolates) but PVL with methicillin-sensitive S. aureus was common (9.0% of all specimens). PVL infection was more frequent in males (OR 3.0, 95% CI 1.3-7.0), and in young adults aged 20-39 years (OR 3.7, 95% CI 1.3-10.4). Over half of PVL positive S. aureus infections originated in patients based in the community. Community-onset PVL-associated disease is common in the UK and mainly causes skin and soft tissue infections that do not require admission to hospital. Consideration should be given to current infection control strategy, which advocates household contact screening and decolonization on the assumption that PVL-associated disease is rare.

Stenotrophomonas and Lysobacter: ubiquitous plant-associated gamma-proteobacteria of developing significance in applied microbiology.

The exploration of new source materials and the use of alternative isolation and identification methods have led to rapid expansion in the knowledge of diversity; in Lysobacter, 11 new species having been described since 2005, and in Stenotrophomonas with six new species since 2000. The new species of Lysobacter, isolated by dilution and direct plating on standard media, differ in several key phenotypic properties from those obtained by enrichment on complex polysaccharides in the original description of the genus. Revision of the definition of the genus will be required. Both culture-dependent and culture-independent methods to assess community structure, in a variety of host and nonhost environments, have established that some species of Lysobacter are a dominant component of the microflora, where previously their presence had not been suspected. Culture-independent studies have generally not added new information on the occurrence and distribution of Stenotrophomonas maltophilia and other members of the genus, which are readily isolated on standard media from source materials. Lysobacter enzymogenes and Sten. maltophilia produce similar antibiotics and share some enzyme activities which, subject to safety considerations, may make them attractive candidates for use in biological control of plant diseases and of nematodes.

Theoretical determination of characteristic x-ray lines and the copper K alpha spectrum.

Core excitations above the K edge result in K alpha characteristic x-ray emission. Understanding these spectra is crucial for high accuracies in investigations into QED, near-edge x-ray structure and advanced crystallography. We address unresolved quantitative discrepancies between experiment and theory for copper. These discrepancies arise from an incomplete treatment of electronic interactions. By finding solutions to relativistic multiconfigurational Dirac-Fock equations accounting for correlation and exchange corrections, we obtain an accurate reproduction of the peak energies, excellent agreement of theory with experiment for the line shapes, good convergence between gauges, and account for the K alpha doublet ratio of 0.522 +/- 0.003ratio1.

Molecular epidemiology of tuberculosis in England, 1998.

SETTING: England. OBJECTIVE: To investigate the proportion of tuberculosis (TB) cases attributable to recent transmission and factors associated with clustering. DESIGN: Demographic, clinical and microbiological surveillance data were collated from all new culture-confirmed cases in 1998. Using insertion sequence (IS) 6110 restriction fragment length polymorphism (RFLP) typing, strains were classified as clustered (identical patterns) or unique and risk factors were determined using multivariable logistic regression. RESULTS: RFLP patterns were available for 2265 of 3713 (61%) cases: 1808 had >or=5 IS6110 copies, while 372 cases were in 152 clusters, giving an estimated proportion due to recent transmission of 12.2%.Pulmonary disease (aOR 1.6; 95%CI 1.1-2.2), previous treatment (aOR 3.7; 2.2-6.5) and homelessness (aOR 5.5; 1.2-24.1) were independent risk factors for clustering. Fourteen per cent of patients of Indian subcontinent origin were clustered compared with 27% of white patients. Many clusters spanned ethnic groups (45%) and geographical regions (47%). CONCLUSION: The calculated proportion of TB cases due to recent transmission is low.Adjusting for missed cases and study duration, it increases to 27.6%. Many cases may arise from reactivation or acquisition outside England. Transmission within England accounted for approximately one in four cases and occurred over wide geographic areas, between ethnic groups and among the homeless. Molecular epidemiology can inform local and national public health action.

Protective effect of antibiotics against serious complications of common respiratory tract infections: retrospective cohort study with the UK General Practice Research Database.

OBJECTIVE: To determine the extent to which antibiotics reduce the risk of serious complications after common respiratory tract infections. DESIGN: Retrospective cohort study. SETTING: UK primary care practices contributing to the general practice research database. DATA SOURCE: 3.36 million episodes of respiratory tract infection. MAIN OUTCOME MEASURES: Risk of serious complications in treated and untreated patients in the month after diagnosis: mastoiditis after otitis media, quinsy after sore throat, and pneumonia after upper respiratory tract infection and chest infection. Number of patients needed to treat to prevent one complication. RESULTS: Serious complications were rare after upper respiratory tract infections, sore throat, and otitis media, and the number needed to treat was over 4000. The risk of pneumonia after chest infection was high, particularly in elderly people, and was substantially reduced by antibiotic use, with a number needed to treat of 39 for those aged > or =65 and 96-119 in younger age groups. CONCLUSION: Antibiotics are not justified to reduce the risk of serious complications for upper respiratory tract infection, sore throat, or otitis media. Antibiotics substantially reduce the risk of pneumonia after chest infection, particularly in elderly people in whom the risk is highest.

Tuberculosis in London: the importance of homelessness, problem drug use and prison.

BACKGROUND: The control of tuberculosis (TB) is founded on early case detection and complete treatment of disease. In the UK, TB is concentrated in subgroups of the population in large urban centres. The impact of homelessness, imprisonment and problem drug use on TB control in London is reviewed. METHODS: A cohort study was undertaken of all patients with TB in Greater London to determine the point prevalence of disease in different groups and to examine risk factors for smear positivity, drug resistance, treatment adherence, loss to follow-up and use of directly observed therapy (DOT). RESULTS: Data were collected on 97% (1941/1995) of eligible patients. The overall prevalence of TB was 27 per 100,000. An extremely high prevalence of TB was seen in homeless people (788/100,000), problem drug users (354/100,000) and prisoners (208/100,000). Multivariate analysis showed that problem drug use was associated with smear positive disease (OR 2.2, p<0.001), being part of a known outbreak of drug resistant TB (OR 3.5, p = 0.001) and loss to follow-up (OR 2.7, p<0.001). Imprisonment was associated with being part of the outbreak (OR 10.3, p<0.001) and poor adherence (OR 3.9, p<0.001). Homelessness was associated with infectious TB (OR 1.6, p = 0.05), multidrug resistance (OR 2.1, p = 0.03), poor adherence (OR 2.5, p<0.001) and loss to follow-up (OR 3.8, p<0.001). In London, homeless people, prisoners and problem drug users collectively comprise 17% of TB cases, 44% of smear positive drug resistant cases, 38% of poorly compliant cases and 44% of cases lost to follow-up. 15% of these patients start treatment on DOT but 46% end up on DOT. CONCLUSIONS: High levels of infectious and drug resistant disease, poor adherence and loss to follow-up care indicate that TB is not effectively controlled among homeless people, prisoners and problem drug users in London.

The interpretation of nucleic acid amplification tests for tuberculosis: do rapid tests change treatment decisions?

OBJECTIVES: To describe changes in treatment decisions after receipt of nucleic acid amplification (NAA) test for the diagnosis of M. tuberculosis. METHODS: Retrospective notes review of treatment decisions in patients receiving a NAA test for suspected pulmonary or non-pulmonary tuberculosis at the Royal Free Hospital in London between March 2001 and February 2002. Notes were sought on a 50% random sample of patients with both smear and NAA negative specimens and all patients with other specimen results. RESULTS: Two hundred and fifty patients were tested with NAA; clinical details were obtained on 138; 61 were ever treated. Seventeen (17/18) smear-negative patients were started on treatment after a positive NAA; none of six smear-negative patients treated prior to a negative NAA result had treatment stopped. Seventeen (17/21) smear-positive patients were treated prior to NAA result and all were NAA positive; treatment was delayed in four smear-positive patients until receipt of an NAA and one NAA-negative patient was not treated. CONCLUSIONS: In routine practice a positive test in an untreated smear-negative patient leads to decision to treat in almost all, but the proportion testing positive is low (8% or 17/219). In patients already on treatment negative tests did not lead to decisions to stop.

Reasons for low reported treatment success in notified tuberculosis patients from a London hospital according to new outcome reporting.

In January 2002 the Communicable Disease Surveillance Centre (CDSC) introduced outcome reporting for tuberculosis 12 months after start of treatment. To determine whether outcome could change with longer and more detailed follow up, we examined this at 12 months and two years for a cohort notified in 2000 at a central London hospital. At 12 months 61/94 (65%) notified patients had completed treatment, 10 (16%) had died, 11 (12%) were lost to follow up, six (6%) were transferred to another service in the UK, four (4%) were still on treatment, and treatment for one (1%) patient had been stopped. After a mean follow up of two years, 65 (69%) had completed treatment. In this London service with a high prevalence of HIV infection (at least 23%), low treatment success was due to deaths, transfers and losses to follow up. The last of these was often due to patients returning to their country of origin (7 of 11). Tuberculosis was the primary or contributing cause of death in at least 4/94 (4%) cases. Completion rates need to be interpreted with caution particularly in specialist units with highly mobile populations. This has implications for national targets as well as for models of care.

Explaining risk factors for drug-resistant tuberculosis in England and Wales: contribution of primary and secondary drug resistance.

Drug-resistant tuberculosis can be transmitted (primary) or develop during the course of treatment (secondary). We investigated risk factors for each type of resistance. We compared all patients in England and Wales with isoniazid- and multidrug-resistant tuberculosis in two time-periods (1993-1994 and 1998-2000) with patients with fully sensitive tuberculosis, examining separately patients without and with previous tuberculosis (a proxy for primary and secondary drug-resistant tuberculosis). Patients with previous tuberculosis smear positivity and arrival in the United Kingdom <5 years were strongly associated with multidrug resistance and isoniazid resistance. In patients with no previous tuberculosis HIV infection, residence in London and foreign birth were risk factors for multidrug resistance, and non-white ethnicity, residence in London and HIV infection for isoniazid resistance. Risk factors for each type of resistance differ. Elevated risks associated with London residence, HIV positivity, and ethnicity were mainly seen in those without previous tuberculosis (presumed transmission).

Epidemiology and control of tuberculosis in Western European cities.

SETTING: Major cities of Western Europe. OBJECTIVE: To describe major variations in the epidemiology and control of tuberculosis in large Western European Cities. DESIGN: Postal survey using contacts identified through the EURO-TB surveillance network. RESULTS: Twenty cities responded. In most cities, notification rates were substantially higher than national rates. Rates ranged from less than 10 per 100,000 in Reykjavik and Belfast to over 70 per 100,000 in Lisbon. MDR-TB ranged from less than 1% of cases in many cities to over 5% in Rome and Milan. The proportion of patients estimated to be HIV-positive ranged from less than 5% in many countries to over 20% in Milan. These variations in epidemiology were accompanied by major variations in control policy, particularly in approaches to new entrant screening and BCG vaccination. CONCLUSION: In Western Europe, tuberculosis is primarily a problem of large cities. Some of these cities have very high rates of tuberculosis. There is little consensus about the best approaches to control. The evidence base for the effectiveness of different aspects of TB control needs to be strengthened.

Risk factors for drug resistant tuberculosis in Leicestershire--poor adherence to treatment remains an important cause of resistance.

In the light of rising numbers of tuberculosis (TB) cases in the United Kingdom, the problem of anti-tubercular drug resistance remains a significant concern. Drug resistant TB cases are more difficult and costly to treat, and require appropriate treatment and control mechanisms. This matched case control study aimed to investigate risk factors for resistance in Leicestershire, using data for laboratory isolates of Mycobacterium tuberculosis identified from 1993 to 1998. Each case, defined as culture positive laboratory isolates resistant to at least one first-line drug, was matched to four fully sensitive controls on age, sex and ethnic group. Twenty-three cases and 81 controls were included in the analysis. Drug resistance in Leicestershire was found to be associated with poor adherence to treatment (OR 4.8, 95% CI 1.6-14.4, P=0.005) and with previous TB (OR 3.7, 95% CI 1.2-11.8, P=0.022). These findings emphasize the need to provide support to patients taking treatment in order to maximize adherence.

The molecular epidemiology of tuberculosis in inner London.

The study used DNA fingerprint typing (spoligotyping and Heminested-lnverse-PCR) of Mycobacterium tuberculosis from all culture-confirmed inner London patients over a 12-month period to describe transmission. The methodology was evaluated by comparison with standard IS6110 typing and by examining its ability to identify known household clusters of cases. Isolates sharing indistinguishable typing patterns using both techniques were defined as clustered. Clusters were investigated to identify epidemiological links. The methodology showed good discriminatory power and identified known household clusters of cases. Of 694 culture-confirmed cases, 563 (81%) were typed. Eleven (2%) were due to laboratory cross-contamination and were excluded. Of the remaining 552 isolates 148 (27%) were clustered. Multivariate analysis indicated that clustering was more common in those with pulmonary smear positive disease (P < 0.02); those born in the United Kingdom (P < 0.0003) and in patients living in south London (P = 0.02). There was also a trend towards clustering being more common in those not known to have HIV infection (P = 0.051). The results suggest that in inner London, recent local transmission makes an important contribution to notification rates.