Socio-epidemiological Aspects of Respiratory Allergic Diseases in Southern Africa

Differences in the health-related quality of life in patients with asthma living in urban and rural areas in the Amur Region of Russian Federation

BACKGROUND

Asthma usually arises from an interaction between host and environmental factors. Growing attention has been paid to a place of residence as a factor shaping health-related quality of life (QoL). This study investigated the rural-urban disparity in QoL among adult asthma patients in the Amur region of Russian Federation.

MATERIALS AND METHODS

This cross-sectional study included 351 randomly selected adults with asthma. We analyzed QoL (SF-36 and AQLQ scores), asthma control (ACT), and anxiety and depression (HADS) depending on the place of residence (urban vs. rural).

RESULTS

The scale "Role Emotional" (RE) of SF-36 was significantly lower in patients from rural areas compared to urban residents (59.3±3.1 vs. 70.4±2.3 points; p = 0.0042). In the urban group, the correlation analysis demonstrated a clear influence of RE on patients' own assessment of their physical functioning (PF, r = 0.53; p<0.0001). Both groups demonstrated low "Social Functioning" (SF). In the group of urban residents, correlation analysis revealed the presence of positive correlations of SF-36 domains reflecting physical (PF, RP, BP) and social functioning (SF, VT) with most scales of both QoL questionnaires. The domains of the emotional sphere (RE and MH) positively correlated with all scales of both QoL questionnaires among urban residents. In the group of rural residents, a comparative analysis showed the absence of significant correlations between more of the QoL scales. Although Asthma Control Test did not differ between groups, we noted a significantly higher need for β2-agonists in rural areas compared to urban areas (4.2±0.6 vs. 2.7±0.3 inh/day, respectively; p = 0.0221). The frequency of urban residents with a clinically significant level of anxiety (56 persons, or 25.2%) turned out to be lower compared to rural residents (45 persons, or 34.8%; χ2 = 34.08; p<0.001).

CONCLUSION

The burden of asthma introduces a greater imbalance in the health-related QoL of rural residents compared to urban residents in the Amur region of the Russian Federation. The absence of interrelationships of some QoL domains in rural residents suggested a disunity of the physical, psychological and social aspects of life. The rural residents suppress physical discomfort by the more frequent use of short bronchodilators. They often showed emotional instability with a predominance of anxiety, which affected the decrease in QoL in the psycho-emotional sphere.

Allergy and Household Living Conditions among Adolescents Living near Gold Mine Tailing Dumps in the Gauteng and North West Provinces of South Africa

This quantitative exploratory baseline study aimed to investigate whether allergy among adolescents was associated with household living conditions, including living near gold mine tailing dumps in South Africa. A questionnaire based on the International Study of Asthma and Allergies was used to collect information on allergy and household risk factors among adolescents (n = 5611). A chi-square test was applied to determine the relationship between community (exposed/unexposed) and confounding variables. Crude and adjusted odds ratios (ORs) and 95% confidence intervals (CI) were calculated using univariate and multiple logistic regression analysis (LRA) to estimate the likelihood of having doctor-diagnosed allergies. The overall prevalence of doctor-diagnosed allergies was 25.5%. The exposed communities had a higher prevalence of doctor-diagnosed allergies (26.97%) compared with the unexposed (22.69%) communities. The study found an association between doctor-diagnosed allergy and having fungus in the house, being female, currently having pets in and around the house, residing in the community for more than three years and living in communities located close to gold mine tailing dumps. Actions to implement buffer zones between gold mine tailing dumps and communities would support Sustainable Development Goals 3 (health) and 11 (sustainable cities and communities), while failing to address the current potential identified risk factors may pose a significant public health challenge. Local policymakers should also apply the precautionary principle to protect the health of children, especially with the location of human settlements relative to air pollution sources.

Current and emerging pharmacotherapy for chronic spontaneous Urticaria: a focus on non-biological therapeutics

INTRODUCTION

Chronic spontaneous urticaria (CSU) refers to urticaria (wheals) or angioedema, which occur for a period of six weeks or longer without an apparent cause. The condition may impair the patient's quality of life.

AREAS COVERED

Treatment for CSU is mainly symptomatic. Both AAAAI/ACAAI practice parameters and EAACI/GA2LEN/EDF/WAO guidelines suggest CSU management in a stepwise manner. First-line therapy is with second-generation H₁-antihistamines. Treatment should be stepped up along the algorithm if symptoms are not adequately controlled. Increasing the dosage of second-generation H₁-antihistamines, with the addition of first-generation H₁-antihistamines, H₂ antagonist, omalizumab, ciclosporin A, or short-term corticosteroid may be necessary. New medications are being developed to treat refractory CSU. They include spleen tyrosine kinase inhibitor, Bruton tyrosine kinase inhibitor, prostaglandin D₂ receptor inhibitor, H₄-antihistamine, and other agents. The authors discuss these treatments and provide expert perspectives on the management of CSU.

EXPERT OPINION

Second-generation H₁-antihistamines remain the first-line therapeutic options for the management of CSU. For patients not responding to higher-dose H₁-antihistamines, international guidelines recommend the addition of omalizumab. Efficacy and safety data for newer agents are still pending. Large-scale, well-designed, randomized, double-blind, placebo-controlled trials will further provide evidence on the safety profile and efficacy of these agents in patients with CSU.

Severe asthma in South Africa: A literature review and management approach for primary care

Severe asthma in South Africa (SA) is underappreciated, especially in the primary care setting. This study highlights the epidemiological context of severe asthma as a phenotypic variant. Primary care practitioners, as first-contact medical providers, need grounding in the management of severe asthma based on the precision of diagnosis and negotiated along the 10-point strategy. The underdiagnosis and undertreatment of asthma ought to inform educational programmes and research in this country.

Pulmonary delivery systems for polyphenols

This review reports on the beneficial pharmacological properties of naturally occurring polyphenols for the treatment of inflammatory pulmonary diseases. In addition, it presents an overview of the different types of inhalable formulations which have been developed in order to achieve efficient delivery of polyphenols to the respiratory tract. The main biological activities of polyphenols (anti-oxidant and anti-inflammatory) are covered, with particular emphasis on the studies describing their therapeutic effects on different factors and conditions characteristic of lung pathologies. Special focus is on the technological aspects which influence the pulmonary delivery of drugs. The various polyphenol-based inhalable formulations reported in the literature are examined with specific attention to the preparation methodologies, aerosol performance, lung deposition and in vitro and in vivo polyphenol uptake by the pulmonary epithelial cells.

Dried blood spot omega-3 and omega-6 long chain polyunsaturated fatty acid levels in 7-9 year old Zimbabwean children: a cross sectional study

BACKGROUND

Omega-3 long chain-polyunsaturated fatty acids (LC-PUFAs)-docosahexaenoic acid (DHA), docosapentaenoic acid (DPA) and eicosapentaenoic acid (EPA)- and omega-6 LC-PUFA arachidonic acid (ARA), are essential for optimum physical and mental development in children. Prior to this study, the blood omega-3 LC-PUFA levels were unknown in Zimbabwean children, particularly in those aged 7-9 years, despite the documented benefits of LC-PUFAs. Documentation of the LC-PUFA levels in this age group would help determine whether interventions, such as fortification, are necessary. This study aimed to determine dried whole blood spot omega-3 and omega-6 LC-PUFA levels and LC-PUFA reference intervals among a selected group of Zimbabwean children aged 7-9 years old.

METHODS

We conducted a cross sectional study from September 2011 to August 2012 on a cohort of peri-urban, Zimbabwean children aged 7-9 years. The children were born to mothers enrolled at late pregnancy into an HIV prevention program between 2002 and 2004. Dried whole blood spots were sampled on butylated hydroxytoluene antioxidant impregnated filter papers and dried. LC-PUFAs were quantified using gas liquid chromatography. Differences in LC-PUFAs between groups were compared using the Kruskal Wallis test and reference intervals determined using non-parametric statistical methods.

RESULTS

LC-PUFAs levels were determined in 297 Zimbabwean children of whom 170 (57.2 %) were girls. The study determined that LC-PUFAs (wt/wt) ranges were EPA 0.06-0.55 %, DPA 0.38-1.98 %, DHA 1.13-3.52 %, ARA 5.58-14.64 % and ARA: EPA ratio 15.47-1633.33. Sixteen participants had omega-3 LC-PUFAs levels below the determined reference intervals, while 18 had higher omega-6 LC-PUFAs. The study did not show gender differences in omega-3 and omega-6 LC-PUFAs levels (all p > 0.05). EPA was significantly higher in the 8 year age group compared to those aged 7 and 9 years (median; 0.20 vs 0.17 vs 0.18, respectively, p = 0.049). ARA: EPA ratio was significantly higher in the 7 year age group compared to those aged 8 and 9 years (median; 64.38 vs 56.43 vs 55.87 respectively, p = 0.014).

CONCLUSIONS

In this cohort of children, lower EPA levels and higher ARA: EPA ratios were observed compared to those reported in apparently healthy children elsewhere. The high ARA: EPA ratios might increase the vulnerability of these children to inflammatory pathologies. Identification and incorporation into diet of locally produced foodstuffs rich in omega-3 LC-PUFAs is recommended as well as advocating for dietary supplementation with omega-3 fish oils and algae based oils.

Risk factors associated with asthma, atopic dermatitis and rhinoconjunctivitis in a rural Senegalese cohort

Background

The World Allergy Organization estimates that 40 % of the world’s population is affected by allergic diseases. The International Study of Asthma and Allergies in Childhood has completed Phase III and it has now become clear that these diseases have increased in developing countries, especially Africa, where prevalence rates were formerly low. Despite an increase in studies in Africa, few sub-Saharan West African countries are represented; the focus has remained on urban populations and little attention has been paid to rural sub-Saharan Africa.

Methods

We performed an allergy survey in a birth cohort of children aged less than 15 years in rural Senegal and implemented an ISAAC questionnaire. We carried out a complete blood count and serological analyses for IgE levels against common allergens and mosquito saliva.

Results

The prevalence rates of asthma, rhinoconjunctivitis (RC) and atopic dermatitis (AD) were 12.8, 12.5 and 12.2 % respectively. Specific IgE (sIgE) levels against mosquito spp. salivary gland antigens were significantly associated with AD; sIgE levels against selected true grasses (Poaceae) were significantly associated with RC. sIgE levels against house dust mite spp. were not associated with asthma, but were significantly correlated with mosquito IgE levels. Such cross-reactivity may blur the association between HDM sIgE and asthma. Consumption of seafood, storing whey cream, using plant fibre bedding and presence of carpet were significantly associated with increased risk of RC. The association of seafood may be the result of histamine intoxication from molluscs prepared by putrefaction. Cat presence and dog contact were associated with increased risk of asthma. Cow contact was associated with increased risk of AD.

Conclusions

Our allergy study in rural West Africa revealed lower prevalence rates than the majority of African urban settings. Although several associated known risk factors were identified, there were associations specific to the region. The identification of probable artefactual dietary phenomena is a challenge for robust diagnosis of allergic disease. The association AD with mosquito saliva, a common allergen in rural settings, warrants specific attention. Further studies in rural Africa are needed to address the aetiology of allergy in a non-urban environment.

Electronic supplementary material

The online version of this article (doi:10.1186/s13223-015-0090-0) contains supplementary material, which is available to authorized users.

Recurrent wheezing is associated with intestinal protozoan infections in Warao Amerindian children in Venezuela: a cross-sectional survey

Background

While in developed countries the prevalence of allergic diseases is rising, inflammatory diseases are relatively uncommon in rural developing areas. High prevalence rates of helminth and protozoan infections are commonly found in children living in rural settings and several studies suggest an inverse association between helminth infections and allergies. No studies investigating the relationship between parasitic infections and atopic diseases in rural children of developing countries under the age of 2 years have been published so far. We performed a cross-sectional survey to investigate the association of helminth and protozoan infections and malnutrition with recurrent wheezing and atopic eczema in Warao Amerindian children in Venezuela.

Methods

From August to November 2012, 229 children aged 0 to 2 years residing in the Orinoco Delta in Venezuela were enrolled. Data were collected through standardized questionnaires and physical examination, including inspection of the skin and anthropometric measurements. A stool sample was requested from all participants and detection of different parasites was performed using microscopy and real time polymerase chain reaction (PCR).

Results

We observed high prevalence rates of atopic eczema and recurrent wheezing, respectively 19% and 23%. The prevalence of helminth infections was 26% and the prevalence of protozoan infections was 59%. Atopic eczema and recurrent wheezing were more frequently observed in stunted compared with non-stunted children in multivariable analysis (OR 4.3, 95% CI 1.3 – 13.6, p = 0.015 and OR 4.5, 95% CI 0.97 – 21.2, p = 0.055). Furthermore, recurrent wheezing was significantly more often observed in children with protozoan infections than in children without protozoan infections (OR 6.7, 95% CI 1.5 – 30.5).

Conclusions

High prevalence rates of atopic eczema and recurrent wheezing in Warao Amerindian children under 2 years of age were related to stunting and intestinal protozoan infections respectively. Helminth infections were not significantly associated with either atopic eczema or recurrent wheezing.