Risk factors for Kaposi's sarcoma among HIV-positive individuals in a case control study in Cameroon

BackgroundIndividuals co-infected with Kaposi's sarcoma herpesvirus (KSHV) and Human Immunodeficiency Virus (HIV) are at greatly increased risk of developing Kaposi's sarcoma (KS). The objective of the current analysis is to identify risk cofactors for KS among HIV-positive individuals.MethodsWe conducted a case-control study of KS in Cameroon on 161 HIV-positive and 14 HIV-negative cases and 680 HIV-positive and 322 HIV-negative controls. Participants answered a physician-administered questionnaire and provided blood and saliva specimens. Antibodies against KSHV lytic, K8.1, and latent, ORF73, antigens were measured by ELISA to determine KSHV serostatus. Conditional logistic regression was performed to determine multivariate odds ratios (OR) and 95% confidence intervals (CI) for risk factors associated with KS among HIV-positive cases and controls.ResultsOverall, 98% (158) of HIV-positive cases, 100% (14) of HIV-negative cases, 81% (550) of HIV-positive controls, and 80% (257) of HIV-negative controls were KSHV seropositive. Risk factors for KS among HIV-positive individuals included KSHV seropositivity (OR = 9.6; 95% CI 2.9, 31.5), non-use of a mosquito bed net (OR 1.9; 95% CI 1.2, 2.9), minority ethnicity (OR = 3.1; 95% CI 1.1, 9.3), treatment from a traditional healer (OR = 2.3; 95% CI 1.5, 3.7), history of transfusion (OR = 2.4; 95% CI 1.5, 3.9), and family history of cancer (OR = 1.9; 95% CI 1.1, 3.1).ConclusionKSHV seroprevalence of ≥80% indicates a high prevalence in the general population in Cameroon. Among HIV-positive individuals, the strong association of KS with non-use of mosquito nets and treatment from traditional healers are compelling findings, consistent with recently reported data from East Africa.     

Risk factors of peripheral arterial disease: a case control study in Sri Lanka

Background

Peripheral artery disease (PAD) is an important global health problem and contributes to notable proportion of morbidity and mortality. This particular manifestation of systemic atherosclerosis is largely under diagnosed and undertreated. For sustainable preventive strategies in a country, it is mandatory to identify country-specific risk factors. We intended to assess the risk factors of PAD among adults aged 40–74 years.

Methods

This case control study was conducted in 2012–2013 in Sri Lanka. Seventy-nine cases and 158 controls in the age group of 40–74 years were selected for the study in order to have case to control ratio 1:2. The criterion for selecting cases and control was based on Ankle brachial pressure index (ABPI). Cases were selected from those who had ABPI 0.85 or less (ABPI ≤0.85) in either lower limb. Controls were selected from those ABPI score between 1.18 and 1.28 in both lower limbs. Only newly identified individuals with PAD were selected as cases. Controls were selected from the same geographical location and within the 5 year age group as cases.

Results

The history of diabetes mellitus more than 10 years (OR 5.8, 95% CI 2.2–14.2), history of dyslipidemia for more than 10 years (OR 4.9, 95% CI 2.1–16.2), history of hypertension for more than 10 years (OR 3.8, 95% CI 1.8–12.7) and smoking (OR 2.9, 95% CI 1.2–6.9), elevated HsCRP (OR 3.7, 95% CI 1.2–12.0) and hyperhomocysteinemia (OR 3.0, 95% CI 1.1–8.1) were revealed as country specific significant risk factor of PAD.

Conclusions

Diabetes mellitus, hypertension, dyslipidemia, smoking as well as elevated homocysteine and HsCRP found as risk factors of PAD. Longer the duration or higher level exposure to these risk factors has increased the risk of PAD. These findings emphasis the need for routine screening of PAD among patients with the identified risk factors.

     

Potential risk factors for diabetic neuropathy: a case control study

Background  

Diabetes mellitus type II afflicts at least 2 million people in Iran. Neuropathy is one of the most common complications of diabetes and lowers the patient's quality of life. Since neuropathy often leads to ulceration and amputation, we have tried to elucidate the factors that can affect its progression.     

Effect of a control project on clinical profiles and outcomes in buruli ulcer: a before/after study in Bas-Congo, Democratic Republic of Congo

Background

Buruli ulcer (BU) is a necrotizing bacterial infection of skin, subcutaneous tissue and bone caused by Mycobacterium ulcerans. Although the functional impairment caused by BU results in severe suffering and in socio-economic problems, the disease remains largely neglected in Africa. The province of Bas-Congo in Democratic Republic of Congo contains one of the most important BU foci of the country, i.e. the Songololo Territory in the District of Cataractes. This study aims to assess the impact of a BU control project launched in 2004 in the Songololo Territory.

Methods

We used a comparative non-randomized study design, comparing clinical profiles and outcomes of the group of patients admitted at the General Reference Hospital (GRH) of the “Institut Médical Evangélique” (IME) of Kimpese 3 years before the start of the project (2002–2004) with those admitted during the 3 years after the start of the project (2005–2007).

Results

The BU control project was associated with a strong increase in the number of admitted BU cases at the GRH of IME/Kimpese and a fundamental change in the profile of those patients; more female patients presented with BU, the proportion of relapse cases amongst all admissions reduced, the proportion of early lesions and simple ulcerative forms increased, more patients healed without complications and the case fatality rate decreased substantially. The median duration since the onset of first symptoms however remained high, as well as the proportion of patients with osteomyelitis or limitations of joint movement, suggesting that the diagnostic delay remains substantial.

Conclusion

Implementing a specialized program for BU may be effective in improving clinical profiles and outcomes in BU. Despite these encouraging results, our study highlights the need of considering new strategies to better improve BU control in a low resources setting.     

Pulmonary hypertension in patients with Martorell hypertensive leg ulcer: a case control study

Background

Martorell hypertensive ischemic leg ulcer (Martorell ulcer) is characterized by distinct alterations in the arteriolar wall of subcutaneous vessels, leading to progressive narrowing of the vascular lumen and increase of vascular resistance. These changes are similar to the alterations observed in pulmonary arterioles in patients with chronic pulmonary hypertension (PH). This study was aimed to assess an association between the two disorders.

Methods

In this case–control study, 14 patients with Martorell ulcer were clinically assessed for the presence of pulmonary hypertension using transthoracic Doppler echocardiography. Data from patients were compared to 28 matched hypertensive controls.

Results

Systolic pulmonary arterial pressure (sPAP) in patients with Martorell ulcer was significantly higher than in the control group (33.8 ± 16.9 vs 25.3 ± 6.5 mmHg, p = 0.023); the prevalence of pulmonary hypertension was 31% (5/14) in patients and 7% (2/28) in controls (p = 0.031). No differences were seen in left heart size and function between patients and controls.

Conclusion

This study provides first evidence that subcutaneous arteriolosclerosis, the hallmark of Martorell ulcer, is associated with PH. These findings suggest that patients with Martorell leg ulcer might be at significant risk to develop elevated pulmonary arterial pressure. Patients with leg ulcers who present with dyspnea should be evaluated by echocardiography for the presence of pulmonary hypertension.     

Adequate wound care and use of bed nets as protective factors against Buruli Ulcer: results from a case control study in Cameroon

Background

Buruli ulcer is an infectious disease involving the skin, caused by Mycobacterium ulcerans. Its exact transmission mechanism remains unknown. Several arguments indicate a possible role for insects in its transmission. A previous case-control study in the Nyong valley region in central Cameroon showed an unexpected association between bed net use and protection against Buruli ulcer. We investigated whether this association persisted in a newly discovered endemic Buruli ulcer focus in Bankim, northwestern Cameroon.

Methodology/Principal Findings

We conducted a case-control study on 77 Buruli ulcer cases and 153 age-, gender- and village-matched controls. Participants were interviewed about their activities and habits. Multivariate conditional logistic regression analysis identified systematic use of a bed net (Odds-Ratio (OR) = 0.4, 95% Confidence Interval [95%CI] = [0.2–0.9], p-value (p) = 0.04), cleansing wounds with soap (OR [95%CI] = 0.1 [0.03–0.3], p<0.0001) and growing cassava (OR [95%CI] = 0.3 [0.2–0.7], p = 0.005) as independent protective factors. Independent risk factors were bathing in the Mbam River (OR [95%CI] = 6.9 [1.4–35], p = 0.02) and reporting scratch lesions after insect bites (OR [95%CI] = 2.7 [1.4–5.4], p = 0.004). The proportion of cases that could be prevented by systematic bed net use was 32%, and by adequate wound care was 34%.

Conclusions/Significance

Our study confirms that two previously identified factors, adequate wound care and bed net use, significantly decreased the risk of Buruli ulcer. These associations withstand generalization to different geographic, climatic and epidemiologic settings. Involvement of insects in the household environment, and the relationship between wound hygiene and M. ulcerans infection should now be investigated.     

Distribution of Mycobacterium ulcerans in buruli ulcer endemic and non-endemic aquatic sites in Ghana

Mycobacterium ulcerans, the causative agent of Buruli ulcer, is an emerging environmental bacterium in Australia and West Africa. The primary risk factor associated with Buruli ulcer is proximity to slow moving water. Environmental constraints for disease are shown by the absence of infection in arid regions of infected countries. A particularly mysterious aspect of Buruli ulcer is the fact that endemic and non-endemic villages may be only a few kilometers apart within the same watershed. Recent studies suggest that aquatic invertebrate species may serve as reservoirs for M. ulcerans, although transmission pathways remain unknown. Systematic studies of the distribution of M. ulcerans in the environment using standard ecological methods have not been reported. Here we present results from the first study based on random sampling of endemic and non-endemic sites. In this study PCR-based methods, along with biofilm collections, have been used to map the presence of M. ulcerans within 26 aquatic sites in Ghana. Results suggest that M. ulcerans is present in both endemic and non-endemic sites and that variable number tandem repeat (VNTR) profiling can be used to follow chains of transmission from the environment to humans. Our results suggesting that the distribution of M. ulcerans is far broader than the distribution of human disease is characteristic of environmental pathogens. These findings imply that focal demography, along with patterns of human water contact, may play a major role in transmission of Buruli ulcer.     

Predictive impact of coronary risk factors in southern Croatia: a case control study

The aim of study was to compare the impact of coronary risk factors on the incidence of acute myocardial infarction (MI) between Croatia, Central and Eastern Europe, and the rest of the world. As a part of the large international INTERHEART case-control study of acute MI in 52 countries (15,152 cases and 14,820 controls) we have investigated the relationship between several known risk factors (smoking, history of hypertension or diabetes, waist/hip ratio, dietary patterns, physical activity, consumption of alcohol, blood apolipoproteins, and psychosocial factors) and MI among patients without previously known coronary heart disease in Southern Croatia. The main identified MI risk factors in Southern Croatia were heavy smoking (>20 cig/day; OR 3.86; 95% CI 2.31-6.46), diabetes mellitus (OR 2.83; 95% CI 1.58-5.23), abnormal ratio of B-100 and A-1 apolipoproteins (OR 2.23; 95% CI 1.28-3.89), elevated waist to hip ratio (OR 1.96; 95% CI 1.21-3.18), and arterial hypertension (OR 1.68; 95% CI 1.15-2.45). Protective was moderate alcohol consumption (OR 0.63; 95% CI 0.40-0.99). The prevalence of major MI risk factors in Croatia is similar to that in the surrounding countries and in the world, accounting for over 90% of the population attributable risk. However, physical activity, dietary and psychosocial factors are seemingly less important in this country, while moderate alcohol consumption is more protective than regionally or globally.     

Risk factors for severe cases of 2009 influenza A (H1N1): a case control study in Zhejiang Province, China

Few case control studies were conducted to explore risk factors for severe cases of 2009 influenza A (H1N1) with the mild cases as controls. Mild and severe cases of 2009 influenza A (H1N1), 230 cases each, were randomly selected from nine cities in Zhejiang Province, China, and unmatched case control study was conducted. This study found that it averagely took 5 days for the severe cases of 2009 influenza A (H1N1) to start antiviral therapy away from onset, 2 days later than mild cases. Having chronic underlying diseases and bad psychological health combined with chronic underlying diseases were two important risk factors for severe cases, and their OR values were 2.39 and 5.85 respectively. Timely anti-viral therapy was a protective factor for severe cases (OR = 0.35, 95% CI: [0.18–0.67]). In conclusion, psychological health education and intervention, as well as timely anti-viral therapy, could not be ignored in the prevention, control and treatment of 2009 influenza A (H1N1).     

Risk factors for preeclampsia in women from Colombia: a case-control study

Background

Preeclampsia (PE) is a multi-causal disease characterized by the development of hypertension and proteinuria in the second half of pregnancy. Multiple risk factors have been associated with the development of PE. Moreover, it is known that these risk factors vary between populations from developed and developing countries. The aim of this study is to identify which risk factors are associated with the development of preeclampsia (PE) among Colombian women.

Methods

A multi-centre case-control study was conducted between September 2006 and July 2009 in six Colombian cities. Cases included women with PE (n = 201); controls were aged-matched pregnant women (n = 201) without cardiovascular or endocrine diseases for a case-control ratio of 1∶1. A complete medical chart, physical examination and biochemical analysis were completed before delivery. Multivariable logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) of potential risk factors associated with PE.

Results

The presence of factors present in the metabolic syndrome cluster such as body mass index >31 Kg/m2 (OR = 2.18; 1.14–4.14 95% CI), high-density lipoprotein <1.24 mmol/L (OR = 2.42; 1.53–3.84 95% CI), triglycerides >3.24 mmol/L (OR = 1.60; 1.04–2.48 95% CI) and glycemia >4.9 mmol/L (OR = 2.66; 1.47–4.81 95%CI) as well as being primigravidae (OR = 1.71; 1.07–2.73 95% CI) were associated with the development of PE, after adjusting for other variables.

Conclusion

Factors present in the cluster of metabolic syndrome and primigravidity were associated with a greater risk of PE among Colombian women. Understanding the role of this cluster of risk factors in the development of PE is of crucial importance to prevent PE and remains to be determined.     

Health services for Buruli ulcer control: lessons from a field study in Ghana

Background

Buruli ulcer (BU), caused by Mycobacterium ulcerans infection, is a debilitating disease of the skin and underlying tissue. The first phase of a BU prevention and treatment programme (BUPaT) was initiated from 2005–2008, in the Ga-West and Ga-South municipalities in Ghana to increase access to BU treatment and to improve early case detection and case management. This paper assesses achievements of the BUPaT programme and lessons learnt. It also considers the impact of the programme on broader interests of the health system.

Methods

A mixed-methods approach included patients'' records review, review of programme reports, a stakeholder forum, key informant interviews, focus group discussions, clinic visits and observations.

Principal Findings

Extensive collaboration existed across all levels, (national, municipality, and community), thus strengthening the health system. The programme enhanced capacities of all stakeholders in various aspects of health services delivery and demonstrated the importance of health education and community-based surveillance to create awareness and encourage early treatment. A patient database was also created using recommended World Health Organisation (WHO) forms which showed that 297 patients were treated from 2005–2008. The proportion of patients requiring only antibiotic treatment, introduced in the course of the programme, was highest in the last year (35.4% in the first, 23.5% in the second and 42.5% in the third year). Early antibiotic treatment prevented recurrences which was consistent with programme aims.

Conclusions

To improve early case management of BU, strengthening existing clinics to increase access to antibiotic therapy is critical. Intensifying health education and surveillance would ultimately increase early reporting and treatment for all cases. Further research is needed to explain the role of environmental factors for BU contagion. Programme strategies reported in our study: collaboration among stakeholders, health education, community surveillance and regular antibiotic treatment can be adopted for any BU-endemic area in Ghana.     

Cardiovascular risk factors and acute-phase response in idiopathic ascending aortitis: a case control study

Introduction  

Idiopathic aortitis is a rare condition characterized by giant cell or lymphoplasmacytic inflammation of the aorta. The purpose of this study was to describe risk factors for the development of idiopathic aortitis.     

Risk factors associated with gastric cancer in patients with a duodenal ulcer

Background: Although gastric cancer (GC) and duodenal ulcer (DU) are both strongly associated with Helicobacter pylori infection, a DU is negatively associated with the risk of GC. The aim of the study is to evaluate histologic risk factors for GC among patients with a DU. Materials and Methods: A total of 541 consecutive patients with GC were prospectively evaluated for the presence of a DU. Control patients with only a DU (n = 89) were recruited from health screening population. Histologic grading was assessed using the updated Sydney system for six gastric biopsies from three regions. GC risk among patients with a DU was evaluated using logistic regression analysis. Results: Among patients with GC, 7.6% (41/541) had a concomitant DU or an ulcer scar. Corpus‐predominant/pangastritis were more frequently found in concomitant GC patients with a DU (90%) than in patients with a DU alone (62%) (p = .001). In patients with a DU, moderate–severe chronic inflammation at the lesser and greater curvatures of corpus was associated with GC risk (OR, 3.70; 95% CI, 1.46–9.36, and OR, 7.72; 95% CI, 3.18–18.7, respectively). Additionally, moderate–severe intestinal metaplasia (IM) at the antrum and corpus lesser curvature was associated with GC risk (OR, 7.52; 95% CI, 3.06–18.5, and OR, 9.25, 95% CI, 2.39–35.8, respectively). Conclusions: A DU is not rare in patients with GC in a high‐risk region of GC. Patients with a DU with chronic corpus gastritis and IM have an increased risk of GC, thus those patients should be followed up for GC development.     

Reproductive factors and breast cancer risk in Palestine: A case control study

BackgroundEarly age at menarche, late age at menopause, and late age at first full-term pregnancy are linked to a modest increase in the risk of developing breast cancer (breast ca). This study aims to investigate the reproductive determinants of breast cancer among women in the West Bank of Palestine.A structured questionnaire was used to collect data in a case-control study (237 registered cases and 237 controls). A multivariate analysis model was used to adjust for the association between women’s reproductive factors and breast ca risk. This study was approved by Al Quds University Ethical Research Committee and the Ministry of Health research unit.ResultsIn the multivariate analysis, menarche after 13 years of age, use of oral contraceptives for more than two months, and hormonal contraceptives use significantly doubled the risk for breast ca (Adjusted Odds Ratio (AOR) = 2.03, 95 % CI: 1.21–4.37, p < 0.011 and AOR = 2.2, 95 % CI: 1.24–4.01, p = 0.008, respectively). Women who used hormone replacement therapy (HRT) were significantly associated with higher odds (5 folds) of having breast ca versus those who did not use them (AOR 5.02, 95 % CI: 1.93–13.06, p = 0.001). Similarly, nulliparous women showed 6 times the odds of breast ca compared with women with one or more children (p = 0.005). Also, parental consanguinity marriage (AOR 2.59, 95 % CI: 1.53–4.36, p = 0.001) and positive family history (AOR 3.88, 95 % CI: 2.19–6.87, p = 0.001) of the condition can be strong determinants for breast ca in this study.ConclusionThis study provides clear evidence that the use of reproductive hormones, whether as a birth control tool or for therapeutic purposes, must be rationalized worldwide and in Palestine in particular.     

Risk factors for severe malaria in Bamako, Mali: a matched case-control study

The aim of this case-control study was to identify epidemiological risk factors for severe malaria among children living in Bamako, a malaria-endemic area. For this, 260 healthy community controls were matched to 130 patients with severe malaria. Conditional multiple logistic regression analysis indicated that all examined independent factors associated with severe malaria are directly related to characteristics of the child's mother, with the exception of the child's own yellow fever vaccination history (odds ratio (OR): 1.93, 95% confidence intervals (CI(95%)) [1.10-3.37]). The following characteristics were all associated with a decreased risk of severe malaria in the child: maternal education (OR: 0.52, CI(95%) [0.31-0.86]), the mother's adequate knowledge about malaria (OR: 0.46, 95% CI(95%) [0.25-0.86]), her use of mosquito bed nets (OR: 0.53, CI(95%) [0.30-0.92]) and breast-feeding for at least 2 years (OR: 0.57, CI(95%) [0.33-0.94]). Conversely, chronic maternal disease (OR: ?3.16, CI(95%) [1.31-7.61]) was associated with an increased risk of severe malaria. These findings strongly support the hypothesis that maternal factors are central to the development of severe malaria in children. Programmes aiming to improve both maternal health and maternal education may reduce the incidence of severe malaria in children and should therefore be advocated in Bamako and in areas with similar epidemiological patterns for malaria.     

Risk factors for congenital cryptorchidism in a prospective birth cohort study

Background

Risk factors for congenital cryptorchidism were investigated in a prospective birth cohort study in Denmark and Finland from 1997 to 2001.

Methodology and Principal Findings

In total, 2,496 boys were examined for cryptorchidism at birth (cryptorchid/healthy: 128/2,368) and three months old (33/2,215). Information on risk factors was obtained antenatally (questionnaire/interview) or at birth from birth records. Use of nicotine substitutes during pregnancy (n = 40) and infertility treatment by intrauterine insemination (n = 49) were associated with an increased risk for cryptorchidism, adjusted odds ratio (95% confidence interval) (OR (95%CI)) 3.04 (95%CI 1.00–9.27) and 3.01 (95%CI 1.27–7.15), respectively. No association was seen for mothers (n = 79) who had infertility treatment in form of intracytoplasmic sperm injection (ICSI) or in vitro fertilization (IVF) treatment (OR 0.71 95%CI 0.21–2.38). In total, 728 (29%) reported to have smoked during pregnancy, however, no increased risk among maternal smokers was found. Furthermore, we found statistically significant associations between cryptorchidism and low birth weight, prematurity, being small for gestational age, substantial vaginal bleeding, and breech presentation, which are in accordance with other studies.

Conclusions and Significance

Our study revealed two novel risk factors for cryptorchidism: intrauterine insemination and the use of nicotine substitutes in pregnancy. This suggests that cryptorchidism may not only be associated to genetic factors, but also to maternal lifestyle and exposure.