Population-based incidence of typhoid fever in an urban informal settlement and a rural area in Kenya: implications for typhoid vaccine use in Africa

Background

High rates of typhoid fever in children in urban settings in Asia have led to focus on childhood immunization in Asian cities, but not in Africa, where data, mostly from rural areas, have shown low disease incidence. We set out to compare incidence of typhoid fever in a densely populated urban slum and a rural community in Kenya, hypothesizing higher rates in the urban area, given crowding and suboptimal access to safe water, sanitation and hygiene.

Methods

During 2007-9, we conducted population-based surveillance in Kibera, an urban informal settlement in Nairobi, and in Lwak, a rural area in western Kenya. Participants had free access to study clinics; field workers visited their homes biweekly to collect information about acute illnesses. In clinic, blood cultures were processed from patients with fever or pneumonia. Crude and adjusted incidence rates were calculated.

Results

In the urban site, the overall crude incidence of Salmonella enterica serovar Typhi (S. Typhi) bacteremia was 247 cases per 100,000 person-years of observation (pyo) with highest rates in children 5–9 years old (596 per 100,000 pyo) and 2–4 years old (521 per 100,000 pyo). Crude overall incidence in Lwak was 29 cases per 100,000 pyo with low rates in children 2–4 and 5–9 years old (28 and 18 cases per 100,000 pyo, respectively). Adjusted incidence rates were highest in 2–4 year old urban children (2,243 per 100,000 pyo) which were >15-fold higher than rates in the rural site for the same age group. Nearly 75% of S. Typhi isolates were multi-drug resistant.

Conclusions

This systematic urban slum and rural comparison showed dramatically higher typhoid incidence among urban children <10 years old with rates similar to those from Asian urban slums. The findings have potential policy implications for use of typhoid vaccines in increasingly urban Africa.     

The impact of skin cancer prevention efforts in New South Wales,Australia: Generational trends in melanoma incidence and mortality

BackgroundIn Australia, skin cancer awareness campaigns have focused on raising the awareness and consequences of skin cancer and highlighting the importance of utilising sun protection.MethodsTrends in melanoma incidence and mortality have been explored elsewhere in Australia and this study sought to examine the trends in NSW. Anonymised incidence and mortality data for in situ and invasive melanoma from 1988 to 2014 were obtained from the NSW Cancer Registry. Trends of melanoma incidence and mortality were analysed using segmented regression to allow for changes over time. Birth cohort patterns were assessed using age–period–cohort models.ResultsOver the period, incidence of in situ melanoma increased in all age groups although the rates were lowest in those under 40 years of age. Incidence of invasive melanoma was either stable or decreased in people under 60, while it increased in those aged 60 and above, particularly in men. Age–period–cohort analysis revealed decreasing age-specific incidence of invasive melanoma under 40 years of age. Melanoma mortality over the period was stable or decreased in all groups except in men aged 60 or over. Overall, mortality rates generally declined or remained stable particularly in recent years.ConclusionIt is encouraging that rates of invasive melanoma are declining in the younger age cohorts – which could be attributed to both primary prevention efforts with individuals protecting their skin as well as early detection through self assessment and clinician performed skin checks. In addition, whilst it is important to monitor the increasing rates of in situ melanoma, the increase is likely due to early detection and treatment of melanoma that could have progressed to invasive melanoma and therefore detection whilst still in situ is an improved outcome. Overall, the results demonstrate the need to continue to improve the understanding of and compliance with primary skin cancer prevention measures in order to reduce population UVR exposure and overall melanoma incidence.     

Quantifying the emergence of dengue in Hanoi, Vietnam: 1998-2009

Background

An estimated 2.4 billion people live in areas at risk of dengue transmission, therefore the factors determining the establishment of endemic dengue in areas where transmission suitability is marginal is of considerable importance. Hanoi, Vietnam is such an area, and following a large dengue outbreak in 2009, we set out to determine if dengue is emerging in Hanoi.

Methods and Principal Findings

We undertook a temporal and spatial analysis of 25,983 dengue cases notified in Hanoi between 1998 and 2009. Age standardized incidence rates, standardized age of infection, and Standardized Morbidity Ratios (SMR) were calculated. A quasi-Poisson regression model was used to determine if dengue incidence was increasing over time. Wavelet analysis was used to explore the periodicity of dengue transmission and the association with climate variables. After excluding the two major outbreak years of 1998 and 2009 and correcting for changes in population age structure, we identified a significant annual increase in the incidence of dengue cases over the period 1999–2008 (incidence rate ratio  = 1.38, 95% confidence interval  = 1.20–1.58, p value  = 0.002). The age of notified dengue cases in Hanoi is high, with a median age of 23 years (mean 26.3 years). After adjusting for changes in population age structure, there was no statistically significant change in the median or mean age of dengue cases over the period studied. Districts in the central, highly urban, area of Hanoi have the highest incidence of dengue (SMR>3).

Conclusions

Hanoi is a low dengue transmission setting where dengue incidence has been increasing year on year since 1999. This trend needs to be confirmed with serological surveys, followed by studies to determine the underlying drivers of this emergence. Such studies can provide insights into the biological, demographic, and environmental changes associated with vulnerability to the establishment of endemic dengue.     

Residential and occupational exposure to sunlight and mortality from non-Hodgkin's lymphoma: composite (threefold) case-control study.

OBJECTIVE: To determine whether non-Hodgkin''s lymphoma mortality is associated with sunlight exposure. DESIGN: Three case-control studies based on death certificates of non-Hodgkin''s lymphoma, melanoma, and skin cancer mortality examining associations with potential sunlight exposure from residence and occupation. SETTING: 24 states in the United States. SUBJECTS: All cases were deaths from non-Hodgkin''s lymphoma, melanoma, and non-melanotic skin cancer between 1984 and 1991. Two age, sex, and race frequency matched controls per case were selected from non-cancer deaths. MAIN OUTCOME MEASURES: Odds ratios for non-Hodgkin''s lymphoma, melanoma, and skin cancer from residential and occupational sunlight exposure adjusted for age, sex, race, socioeconomic status, and farming occupation. RESULTS: Non-Hodgkin''s lymphoma mortality was not positively associated with sunlight exposure based on residence. Both melanoma and skin cancer were positively associated with residential sunlight exposure. Adjusted odds ratios for residing in states with the highest sunlight exposure were 0.83 (95% confidence interval 0.81 to 0.86) for non-Hodgkin''s lymphoma, 1.12 (1.06 to 1.19) for melanoma, and 1.30 (1.18 to 1.43) for skin cancer. In addition, non-Hodgkin''s lymphoma mortality was not positively associated with occupational sunlight exposure (odds ratio 0.88; 0.81 to 0.96). Skin cancer was slightly positively associated with occupational sunlight exposure (1.14; 0.96 to 1.36). CONCLUSIONS: Unlike skin cancer and to some extent melanoma, non-Hodgkin''s lymphoma mortality was not positively associated with exposure to sunlight. The findings do not therefore support the hypothesis that sunlight exposure contributes to the rising rates of non-Hodgkin''s lymphoma.     

TETANUS IN CALIFORNIA—Epidemiology and a Review of 232 Cases

A study was made of records of the 232 reported cases of tetanus in California, from 1953 through 1958. Cases occurred in 30 of California''s 58 counties. Two-thirds of the patients lived in suburban and urban areas. Two-thirds of the cases occurred in persons over the age of 20 years. The incidence was twice as high in males as in females. Forty-seven per cent of the patients died, with the highest death rates being in persons over the age of 40 years.Sixty-three per cent of the injuries associated with these 232 cases occurred in the home environment and 17 per cent at the place of employment.Ninety-one per cent of the patients had never been immunized with tetanus toxoid, or if they had been immunized, had not received the booster injections necessary to maintain effective immunity. Nine per cent gave a history of having had one or more injections of tetanus toxoid within five years.     

Mortality from and Incidence of Pesticide Poisoning in South Korea: Findings from National Death and Health Utilization Data between 2006 and 2010

Pesticide poisoning has been recognized as an important public health issue around the world. The objectives of this study were to report nationally representative figures on mortality from and the incidence of pesticide poisoning in South Korea and to describe their epidemiologic characteristics. We calculated the age-standardized rates of mortality from and the incidence of pesticide poisoning in South Korea by gender and region from 2006 through 2010 using registered death data obtained from Statistics Korea and national healthcare utilization data obtained from the National Health Insurance Review and Assessment Service of South Korea. During the study period of 2006 through 2010, a total of 16,161 deaths and 45,291 patients related to pesticide poisoning were identified, marking respective mortality and incidence rates of 5.35 and 15.37 per 100,000 population. Intentional self-poisoning was identified as the major cause of death due to pesticides (85.9%) and accounted for 20.8% of all recorded suicides. The rates of mortality due to and incidence of pesticide poisoning were higher in rural than in urban areas, and this rural-urban discrepancy was more pronounced for mortality than for incidence. Both the rate of mortality due to pesticide poisoning and its incidence rate increased with age and were higher among men than women. This study provides the magnitude and epidemiologic characteristics for mortality from and the incidence of pesticide poisoning at the national level, and strongly suggests the need for further efforts to prevent pesticide self-poisonings, especially in rural areas in South Korea.     

Problems in determining the incidence of cervical cancer.

Since cancer registries have different recording practices, the incidence rates that they report must be compared with caution. Indexes of reliability of recording indicated that in 1971 the reported incidence of cervical cancer in Ontario was too high. In 1971 Ontario used a method of passive reporting of cancer cases: the Ontario Cancer Registry linked hospital reports, death certificates and reports from the Ontario Cancer Treatment and Research Foundation''s treatment centres to produce a single record for each case. Pathological confirmation was requested for cases thus recorded by the registry. In 26% of cases a diagnosis other than cervical cancer was indicated. With these cases omitted, the incidence rate became 15.1/100 000, as opposed to the 20.5/100 000 reported by the registry.     

Marked increase in breast cancer incidence in young women: A 10-year study from Northern Iran, 2004–2013

IntroductionBreast cancer is the most frequent cancer among women worldwide. Breast cancer incidence in young women is a health issue of concern, especially in middle-income countries such as Iran. The aim of this study is to report the breast cancer incidence variations in Golestan province, Iran, over a 10-year period (2004–2013).MethodsWe analyzed data from the Golestan Population-based Cancer Registry (GPCR), which is a high-quality cancer registry collecting data on primary cancers based on standard protocols throughout the Golestan province. Age-standardized incidence rates (ASRs) and age-specific incidence rates per 100,000 person-years were calculated. Time trends in ASRs and age-specific rates were evaluated using Joinpoint regressions. The average annual percentage change (AAPC) with correspondence 95% confidence intervals (95%CIs) were calculated.ResultsA total of 2106 new breast cancer cases were diagnosed during the study period. Most cases occurred in women living in urban areas: 1449 cases (68%) versus 657 cases (31%) in rural areas. Statistically significant increasing trends were observed over the 10-year study period amongst women of all ages (AAPC = 4.4; 95%CI: 1.2–7.8) as well as amongst women in the age groups 20–29 years (AAPC = 10.0; 95%CI: 1.7–19.0) and 30–39 years (AAPC = 5.1; 95%CI: 1.4–9.0).ConclusionThe incidence of breast cancer increased between 2004 and 2013 in Golestan province amongst all age groups, and in particular amongst women aged 20–39 years. Breast cancer should be considered a high priority for health policy making in our community.     

Twenty years of melanoma in Victoria,Queensland, and South Australia (1997 – 2016)

BackgroundGiven the high incidence of melanoma in Australia alongside high mortality with later stage disease, we investigated the populations and locations most at risk, to optimise public health activities in areas where intervention is most needed. This study examines trends and identifies significant prognostic factors and potential disparities in incidence, mortality and survival between population groups in Victoria, Queensland and South Australia.MethodsThe analysis includes data from the population-based cancer registries of the three states over a twenty-year period (1997–2016). Age-standardized and age-specific incidence rates were calculated, and long-term trends analysed using Joinpoint Regression. Five-year relative survival estimates for the study population were calculated using the cohort method and multivariable flexible parametric survival models were applied for each jurisdiction to calculate adjusted excess mortality hazard ratios for the key characteristics.ResultsThere were more males with melanoma than females in all the three states. Over 60% of the cases occurred in the 40–74 years age group. Most melanomas had a Breslow thickness less than or equal to 1.0 mm. For males, Victoria and Queensland had a statistically significant increasing trend whereas in South Australia there was a decreasing trend. For females, the incidence rate trend was stable in Victoria but significantly decreasing in South Australia. In Queensland there was an increasing and statistically significant trend from 2006 to 2016. Across all three states there was a reducing incidence rate in the youngest cohort, stabilizing incidence in the 40–59-year-old age group, and increasing in the oldest cohorts. Five-year relative survival decreased with increasing age and with Breslow thickness across all three jurisdictions. Males had between 43%− 46% excess mortality compared to females in all the three states. There was higher risk with increasing age and Breslow thickness, with the largest risk among the 75 + age group and those with a Breslow thickness of > 4 mm.ConclusionIt is the first time that data from these three registries has been analysed together in a uniform way, covering more than half of the Australian population. This study compares the epidemiology of melanoma across three states and provides a better understanding of trends and factors affecting outcome for Australians with melanoma. While there has been some improvement in aspects of incidence and mortality, this has not been evenly achieved across Australia.     

Epidemiologic features of cerebrovascular disease in Manitoba: incidence by age,sex and residence,with etiologic implications.

To determine the incidence of and risk factors in cerebrovascular disease in Manitoba, all 1367 new cases in defined areas (population, 660 391) in an 18-month period were studied. Pertinent data were collected from hospital records, death certificates and autopsy reports. The annual incidence of cerebrovascular disease in these areas was 138/100 000 and the incidence was generally higher in men than in women. The incidence of cerebral infarction (INF) and that of hemorrhage (HGE) were similar in men and women less than 50 years old; thereafter the incidence of INF increased faster with age than did that of HGE, the disparity being greater in men than in women, whereas the incidence of HGE increased at similar rates in the two sexes. The incidence of INF was significantly greater in men than in women in urban areas, and in men it was greater in urban than in rural areas. Elevated concentrations of serum lipids and smoking are implicated as risk factors in INF, and hypertension as a risk factor in HGE.     

A melanoma trend forecast from 2002 – What happened then?

ABSTRACT

In 2002, a paper was published that highlighted the strong correlation noticed between melanoma incidence and the number of surrounding frequency modulation (FM) transmitters in the Nordic countries since 1955. In the report the development of future numbers of melanoma cases in Estonia were estimated since they got the FM broadcasting system rolled out not until 1992. Here, we report what happened since then in Estonia regarding melanoma cases per year. We also comment on the recent development in the Nordic countries, which is not very reassuring from a public health point of view. The last 10 years of melanoma incidence trends, increasing at an exponential rate, suggest that responsible authorities now need to consider possible influences also from other radiation sources in addition to UV radiation from the sun.     

Decline in measles mortality: nutrition,age at infection,or exposure?

The mortality from measles was studied in an urban area of Guinea-Bissau one year before and five years after the introduction of a vaccination programme. The years after the introduction of immunisation saw a decline in mortality among unvaccinated children with measles. This decline occurred despite a lower age at infection and an increasing prevalence of malnourished children. State of nutrition (weight for age) did not affect the outcome of measles infection. The incidence of isolated cases, however, increased in the period after the introduction of measles vaccination. As mortality was lower among these cases, diminished clustering explained some of the reduction in mortality. Comparison between the urban district and a rural area inhabited by the same ethnic group showed a lower age at infection, less clustering of cases, and lower case fatality ratios in the urban area.Endemic transmission of measles in urban districts leads to less clustering of cases, which may help explain the usually lower case fatality ratios in these areas. As measles vaccination increases herd immunity and diminishes clustering of cases, it may reduce mortality even among unvaccinated children who contract the disease.     

Cutaneous malignant melanoma in Scotland: incidence,survival, and mortality, 1979-94. The Scottish Melanoma Group.

OBJECTIVE: To determine the changing incidence of and mortality from cutaneous malignant melanoma in Scotland from 1979 to 1994. DESIGN: Detailed registration of clinical and pathological features, surgical and other treatment, and follow up of all cases of cutaneous malignant melanoma diagnosed from 1979 to 1994 and registered with specialist database for Scotland. SETTING: Scotland. SUBJECTS: 6288 patients with invasive primary cutaneous malignant melanoma diagnosed between 1 January 1979 and 31 December 1994. RESULTS: The annual age standardised incidence of cutaneous malignant melanoma rose significantly from 3.5 to 7.8 per 100,000 per year in men and from 6.8 to 12.3 per 100,000 per year in women (P < 0.001 for both). World standardised rates increased from 2.7 to 6.0 per 100,000 per year in men and 4.6 to 8.50 per 100,000 in women. The incidence of melanoma continued to increase significantly in men of all ages during the study, but the rate stabilised in women after 1986. Mortality from cutaneous malignant melanoma was 1.3 per million per annum in men in 1979, rising to 2.3 per million per annum in 1994 (P < 0.01); it was 2.4 per million per annum in women in 1979, falling to 1.9 per million per annum in 1994 (P = 0.09). The underlying mortality trends showed a continuing rise for men but a downward trend for women that was not significant (P = 0.09). In men, melanoma free survival was 69% at 5 years and 61% at 10 years; in women the corresponding rates were 82% and 75%. Younger patients had higher survival rates, which were not entirely explained by thinner tumours. Over the 15 year period, survival rates improved by 12% overall, only partly owing to thinner tumours. CONCLUSIONS: In Scotland the incidence of melanoma in women has stabilised, while mortality associated with melanoma in women shows a downward trend.     

Incidence of leukaemia in young people in the vicinity of Hinkley Point nuclear power station, 1959-86.

The incidence of leukaemia and non-Hodgkin''s lymphoma in young people (aged under 25) living in a predefined area around the nuclear power station at Hinkley Point, Somerset, was examined for the period 1959-86 by using cancer registry data. During the period since Hinley Point began operations--that is, 1964-86--there were 19 cases in the area compared with 10.4 expected from national rates, giving a standardised registration ratio of 1.82 (95% confidence interval 1.10 to 2.85). The incidence in the rest of Somerset was also high, however (standardised registration ratio 1.18; 95% confidence interval 0.98 to 1.41), and the high rate around Hinkley Point may simply have been reflecting the high local incidence (ratio of the two standardised registration ratio''s 1.54; 95% confidence interval 0.90 to 2.52). Analysis of predetermined five year periods showed that the excess cases in the Hinkley Point area were concentrated in the 10 years 1964-73 after commissioning of the station, at a time when rates in the rest of Somerset were close to the national average. In particular the nine cases occurring in the five years 1969-73 were about four times the number expected from national rates (standardised registration ratio 3.96; 95% confidence interval 1.81 to 7.52). Rates in the Hinkley Point area after 1973 were fairly low, especially as compared with the rest of Somerset. In the five years 1959-63 (that is, before Hinkley Point was commissioned) rates throughout Somerset (including the Hinkley Point area) were higher than the national rate. These findings should be interpreted with caution, and further studies are required to test the plausibility of theories relating to radiation and viruses.     

Melanoma in patients with GATA2 deficiency

GATA2 deficiency is a recently described genetic disorder affecting hematopoietic stem cells and is associated with immunodeficiency, hematologic malignancy, and various cutaneous pathologies including cutaneous tumors. To explore the incidence and clinical course of melanoma in patients with germline GATA2 deficiencies, we conducted a retrospective chart review of 71 such patients and identified two with invasive melanoma. One melanoma was diagnosed early because it was associated with pruritus due to a graft‐versus‐tumor effect following bone marrow transplantation. The other one, a lentigo maligna melanoma, was locally excised but progressed to widespread metastasis and death several years later. Our observations and published studies of melanoma biology suggest an association between decreased GATA2 expression and melanoma progression. These findings suggest that GATA2 deficient patients may have an increased risk of melanoma and should be observed closely for new or changing skin lesions.     

Insulin dependent diabetes in childhood and material deprivation in northern England, 1977-86.

OBJECTIVE--To determine the incidence of insulin dependent diabetes in the Northern region of England in children less than 16 years old in the period 1977 to 1986 and to relate the incidence data to an index of deprivation. DESIGN--Retrospective analysis of hospital case records identified from the regional health authority''s computer; validation of the primary source with hospital clinic registers and community paediatric registers. SETTING--Northern region, excluding South Cumbria District Health Authority (659,300 children under 16 in 1981). PATIENTS--All children diagnosed with insulin dependent diabetes before the age of 16 and resident in the region at time of diagnosis. MAIN OUTCOME MEASURES--Incidence rates for the 10 year period and analysis of incidence rates within categories of deprivation. RESULTS--919 incident cases were identified. The validation procedure covered 54% of all cases identified and gave 95% completeness of ascertainment. The average annual incidence over the 10 year period was 14.8/100,000 for girls and 13.4/100,000 for boys. The annual incidence for the most and least deprived areas of the region was 18.7/100,000 (95% confidence interval 16.2 to 21.5) for boys and 7/100,000 (5.6 to 8.8) for girls. There was a highly significant trend (p less than 0.001) of decreasing incidence with decreasing level of deprivation. CONCLUSIONS--In the north of England the incidence of childhood diabetes is related to material deprivation.     

Epidemiologic and economic burden of influenza in the outpatient setting: a prospective study in a subtropical area of china

Objectives

To understand the incidence of outpatient influenza cases in a subtropical area of China and the associated economic burden on patients'' families.

Methods

A hospital-based prospective study was conducted in Zhuhai City during 2008–2009. All outpatient influenza-like illness (ILI) cases were identified in 28 sentinel hospitals. A representative sample of throat swabs from ILI cases were collected for virus isolation using Madin-Darby canine kidney cells. The incidence of outpatient influenza cases in Zhuhai was estimated on the basis of the number of influenza patients detected by the sentinel sites. A telephone survey on the direct costs associated with illness was conducted as a follow-up.

Results

The incidence of influenza was estimated to be 4.1 per 1,000 population in 2008 and 19.2 per 1,000 population in 2009. Children aged <5 years were the most-affected population, suffering from influenza at the highest rates (34.3 per 1,000 population in 2008 and 95.3 per 1,000 population in 2009). A high incidence of 29.2–40.9 per 1000 population was also seen in young people aged 5–24 years in 2009. ILI activity and influenza virus isolations adopted a consistent seasonal pattern, with a summer peak in July 2008 and the longest epidemic period lasting from July–December 2009. The medical costs per episode of influenza among urban patients were higher than those for rural patients. A total of $1.1 million in direct economic losses were estimated to be associated with outpatient influenza during 2008–2009 in Zhuhai community.

Conclusions

Influenza attacks children aged <5 years in greater proportions than children in other age groups. Seasonal influenza 2008 and Pandemic influenza A (H1N1) 2009 had different epidemiological and etiological characteristics. Direct costs (mostly medical costs) impose an enormous burden on the patient family. Vaccination strategies for high-risk groups need to be further strengthened.     

Incidence of malignancy in adult patients with rheumatoid arthritis: a meta-analysis

IntroductionPatients with rheumatoid arthritis (RA) are at an increased risk of malignancies compared with the general population. This has raised concerns regarding these patients, particularly with the widespread use of immunomodulating therapies, including biologic disease-modifying antirheumatic drugs (DMARDs). We performed a systematic literature review and analysis to quantify the incidence of malignancies in patients with RA and the general population to update previously published data.MethodsA literature search was conducted that was consistent with and similar to that in a meta-analysis published in 2008. MEDLINE, BIOSIS Previews, Embase, Derwent Drug File and SciSearch databases were searched using specified search terms. Predefined inclusion criteria identified the relevant observational studies published between 2008 and 2014 that provided estimates of relative risk of malignancy in patients with RA compared with the general population. Risk data on overall malignancy and site-specific malignancies (lymphoma, melanoma and lung, colorectal, breast, cervical and prostate cancer) were extracted. The standardized incidence ratios (SIRs; a measure of risk) relative to the general population were evaluated and compared with published rates.ResultsA total of nine publications met the inclusion criteria. Seven of these reported SIRs for overall malignancy; eight for lymphoma, melanoma, and lung, colorectal and breast cancer; seven for prostate cancer; and four for cervical cancer. Compared with those in the general population, the SIR estimates for patients with RA suggest a modest increased risk in overall malignancy, as previously observed. Patients with RA continued to show an increased risk of lymphoma and lung cancer compared with the general population. Overall, SIR estimates for colorectal and breast cancers continued to show a decrease in risk, whereas cervical cancer, prostate cancer and melanoma appeared to show no consistent trend in risk among patients with RA compared with the general population.ConclusionsThe additional data evaluated here are consistent with previously reported data. Patients with RA are at an increased risk of lung and lymphoma malignancies compared with the general population. Quantifying differences in malignancy rates between non-biologic and biologic DMARD-treated patients with RA may further highlight which malignancies may be related to treatment rather than to the underlying disease.     

The Incidence of Inflammatory Bowel Disease in Northern China: A Prospective Population-Based Study

Aims & Backgrounds

Although inflammatory bowel diseases (IBD) are emerging and increasing in China, epidemiologic data are rarely available. This study was to investigate the epidemiological and clinical characteristics of IBD in Northern China.

Methods

This is a prospective, population-based study of incidence of IBD in Daqing,Heilongjiang province of Northern China from March 1, 2012 to February 28, 2013. All incident patients with IBD were clinically identified by IBD specialist group from five main General Hospitals covering the healthcare service for 1,343,364 residents in the urban areas of Daqing. IBD cases included in this study were followed-up for three months for diagnosis confirmation.

Results

A total of 27 new IBD cases including 25 cases of ulcerative colitis (UC) and 2 cases of Crohn''s disease (CD) were identified. The population at risk was 1,343,364 person years. Age-adjusted incidence for total IBD, CD and UC were 1.77, 0.13, and 1.64 per 100,000population, respectively. A male predominance was found in CD patients (male to female ratio was 2∶0). In contrast, no obvious gender predominance was found in UC patients (male to female ratio was 1∶1.1). CD patients were diagnosed at an average age of 39.5 years. The main disease phenotypes of UC were distal colitis with a 24% of proctitis and 56% of left-sided colitis. The mean diagnostic age of UC patients was 48.9 years.

Conclusions

This is the first report on the incidence of IBD in the Northern Chinese population. A lower incidence of IBD, similar male predominance for CD, similar disease phenotype of UC, and lower disease activity was observed in Daqing compared to that in Southern China.     

Comprehensive analysis of prognostic immune-related genes in the tumor microenvironment of cutaneous melanoma

Cutaneous malignant melanoma (hereafter called melanoma) is one of the most aggressive cancers with increasing incidence and mortality rates worldwide. In this study, we performed a systematic investigation of the tumor microenvironmental and genetic factors associated with melanoma to identify prognostic biomarkers for melanoma. We calculated the immune and stromal scores of melanoma patients from the Cancer Genome Atlas (TCGA) using the ESTIMATE algorithm and found that they were closely associated with patients’ prognosis. Then the differentially expressed genes were obtained based on the immune and stromal scores, and prognostic immune-related genes further identified. Functional analysis and the protein–protein interaction network further revealed that these genes enriched in many immune-related biological processes. In addition, the abundance of six infiltrating immune cells was analyzed using prognostic immune-related genes by TIMER algorithm. The unsupervised clustering analysis using immune-cell proportions revealed eight clusters with distinct survival patterns, suggesting that dendritic cells were most abundant in the microenvironment and CD8⁺ T cells and neutrophils were significantly related to patients’ prognosis. Finally, we validated these genes in three independent cohorts from the Gene Expression Omnibus database. In conclusion, this study comprehensively analyzed the tumor microenvironment and identified prognostic immune-related biomarkers for melanoma.